Blackmagic Pocket Camera 4K vs Arri Alexa

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Wayne Steven

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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostTue Oct 09, 2018 2:32 am

16 stop+ is quality. Refer to the discussion above saying XYZ is good if you are grading to 10 stops, and the whole thing of stops on digital not being as much as equivalent stops on film, about context of my post.

I did say you would have to work at it (to get that 16+ stop look). It's pragmatic rather than luxury compared to showing one can work lower latitude fur the sake of it. Less time setting up and filming means less dollars spent, and more time spent on actual art. Which is better results, and cost efficiencies on big budget more than the camera is worth (hence Alexa compared to Red MX). If you can work the image going into a 13 stop image device, you can work the image for a 16+ stop device. So the AI holodeck like stuff may just win out.
aIf you are not truthfully progressive, maybe you shouldn't say anything
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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostTue Oct 09, 2018 2:45 am

Yes, because no film shot on a camera that doesn’t have 16+ stops of dynamic range can be considered “quality”.

Definitely nothing shot on the AF100 with 10 stops of dynamic range like The Raid: Redemption, or most of the last season of House shot on the 5D mkii.
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Wayne Steven

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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostTue Oct 09, 2018 5:48 am

Michael, I'm talking about more quality. Isn't that a better thing.

I thought it was one episode (and it stood out). Most of House is shot on a controlled set. If they put in enough effort they could shoot it on a four stop camera. We all shoot it like the second season of Vikings. But a better camera makes it easier to pick a wider range of styles.

I was wondering about the contrast in Barry L. Thanks for the heads up Michael.

Anyway guys, what's the point of people coming the eyes out seperate debates?
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Ulysses Paiva

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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostTue Oct 09, 2018 9:27 am

If you say you need 10k, 16 stops+, 14 stops, 8k, superoversampling, and stuff, you missed the point the discussion went to. And you are exactly like guys already described, someone too attatched to specs rather than looking at the picture.
Generally, true talented people doesnt rely so much on specs, they simply make it work. Its just a tool for you to use your talent. And cinema is just making it work with what you got, not pulling excuses blaming the gear. Who here didnt see DIY for all cinema history even in big budget? Kubrick even used a simple ligh bulb to light "The Shinning" when he could have a much fancier lighting.
John Brawley is doing a terrific work using the 4.6k on "The Resident" and he could easily be using an Alexa.
Of course better tools helps you achieve better results, but only on the hands of those who know what they are doing. You just need to have a tool good enough for what you want to do and that goes beyond specs to the point where specs might not even matter.
Do you think Roger Deakins moved to the Alexa for Blade Runner 2049 because specs or because it produced the results he wanted?
Do you think Kubrick relied on the camera specs to make the job for him or he even designed new tools not because specs but to achieve the look he was after?
We are too much spec dependant and thats why we are each time producing less "classics". Its lacking soul and true talent being trade for ease of use and specs to impress.
Some just need to think they have bigger dicks and some just dont care because they trust in what they got to make it work beatifully.
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Wayne Steven

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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostTue Oct 09, 2018 11:50 am

What are you talking about. I mention all this 10k stuff questioning if it is real quality resolution on the film (in the context it was used), or a positional pickup system. A matter of is the spec really relevant of showing off something not really there in the context (how to interpret what the spec really means). I mention a few other things to open eyes to reality of what experts are finding, that higher resolutions are not useless, but give better debayering results to normal delivery resolutions. To show what the lens does to the image, better transfering the look.

I mention quality issues. Don't be fooled by people trying to trump it saying that specifications don't mean anything because they don't understand what they mean. Specs are scientific, not wishy washy thinking, which wishy washy thinking people point to as wishy washy. Reality is a lot of stuff, a lot of specs, a lot of science, which does describe things. They describe what you are eyeballing.

These arguments are rather like arguing $4 or 4 stops is as much value as $16 or 16 stops after they put in $32 of work to get it to match, of course the 16 is better and only somebody mentally challenged thinks otherwise. Doesn't matter if one rambles on, and make no mistake about it, that is exactly what it is in the real world, physically rambling on to work an image to fit in 4 stops (or whatever) like it's 16 stops, instead of getting a life and getting a better camera to start with. That's what high end professionals do, buy an Alexa get better results and less hassles, and then it will be another model of camera is suddenly better etc, whatever suites at the moment as well, even a light bulb in the shinning. And the big irony is, that these professionals are always judging by specifications. They simply are judging the dimension/values of the look of the picture (the specs) by eye. It is just a different way of measuring specs. But, if you got the sheets of specs, without even seeing a picture, you can both get an idea of which is better but even how they look different.

But people want to eye pick a few specs that don't describe everything and ramble on how specs can't be trusted, don't trust them. There are words for this I can't use here. There is an avalanche of information in real life, it is a matter of pursuit of discovery to find the truth.
aIf you are not truthfully progressive, maybe you shouldn't say anything
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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostTue Oct 09, 2018 1:07 pm

I'm agree with Wayne Steven.
Some cameras can hold better dynamic range than others even they have same on the paper.
Lots stops away from the key without good color performance could be a nightmare if not a good camera. Well, this is one of the reason we’ve lighting tools. As well one of the reasons some stuff look flat or over lighted, even cheap tone mapping photoshop filter look if try make a 13 stops camera look like 16 stops.

Anyway P4k not gonna be A cam for Blade Runner but is a great camera. Study your exposure ratios, use false color and have fun. For sure if you know what you want it going to look great.
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Rakesh Malik

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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostTue Oct 09, 2018 2:22 pm

Wayne Steven wrote:But people want to eye pick a few specs that don't describe everything and ramble on how specs can't be trusted, don't trust them. There are words for this I can't use here. There is an avalanche of information in real life, it is a matter of pursuit of discovery to find the truth.


No, you're still completely missing the point with your inane ramblings.

The specs aren't what make for great images. Roger Deakins selected Alexas for Blade Runner 2049 over Alexa 65s, even though he had the choice. If any of your silliness had any merit, he'd have gone with Alexa 65s for the resolution, since Alexas are "only" 3.2K cameras (and that's only when they're open gate -- since he didn't shoot anamorphic, he didn't even use a full 3.2K).

In spite of that, Blade Runner 2049 was absolutely gorgeous... but never just for the sake of looking gorgeous.

So obviously, specs aren't anywhere near the big deal that you or any other spec hounds make them out to be.
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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostTue Oct 09, 2018 3:02 pm

Rakesh Malik wrote:
Wayne Steven wrote:But people want to eye pick a few specs that don't describe everything and ramble on how specs can't be trusted, don't trust them. There are words for this I can't use here. There is an avalanche of information in real life, it is a matter of pursuit of discovery to find the truth.


No, you're still completely missing the point with your inane ramblings.

The specs aren't what make for great images. Roger Deakins selected Alexas for Blade Runner 2049 over Alexa 65s, even though he had the choice. If any of your silliness had any merit, he'd have gone with Alexa 65s for the resolution, since Alexas are "only" 3.2K cameras (and that's only when they're open gate -- since he didn't shoot anamorphic, he didn't even use a full 3.2K).

In spite of that, Blade Runner 2049 was absolutely gorgeous... but never just for the sake of looking gorgeous.

So obviously, specs aren't anywhere near the big deal that you or any other spec hounds make them out to be.


+1
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Ulysses Paiva

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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostTue Oct 09, 2018 4:57 pm

Rakesh Malik wrote:The specs aren't what make for great images. Roger Deakins selected Alexas for Blade Runner 2049 over Alexa 65s, even though he had the choice. If any of your silliness had any merit, he'd have gone with Alexa 65s for the resolution, since Alexas are "only" 3.2K cameras (and that's only when they're open gate -- since he didn't shoot anamorphic, he didn't even use a full 3.2K).

In spite of that, Blade Runner 2049 was absolutely gorgeous... but never just for the sake of looking gorgeous.



Great point. I even forgot the Alexa 65 because seems it is not being much used as I thought it would.
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Oyvind Fiksdal

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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostTue Oct 09, 2018 6:06 pm

Rakesh Malik wrote:Roger Deakins selected Alexas for Blade Runner 2049 over Alexa 65s, even though he had the choice.


Well, I would say Bladerunner 2049 was destined to emulate the feel from the first one, and super high res was not one of its features. That doesn’t mean 2049 look bad. It looks great! I was actually more surprised they didn’t use film.

Another example is Guardian of the galaxy vol 1 that was shot on alexa xt vs vol 2 shot on RED/phantom flex 4k. Did vol 1 look worse? Hell no. Why they ditched alexa for vol2 guardian is a bit of a mystery to me, when you see the quality of the first one. I guess lobbying still works ;)

Dunkirk , in IMAX 70mm made perfect sense, since they almost went 100% practical effects. IMO the texture/IQ made its own appealing effect. Perfect for that movie.

There is always time, or not, for high res. Resolution is almost a kryptonite for heavy fx work. It only means you will spend more time in post, adding cost. Its not many years since 2k was “agreed” to be good enough.
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Rakesh Malik

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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostTue Oct 09, 2018 6:44 pm

Oyvind Fiksdal wrote:Well, I would say Bladerunner 2049 was destined to emulate the feel from the first one, and super high res was not one of its features. That doesn’t mean 2049 look bad. It looks great! I was actually more surprised they didn’t use film.


Roger Deakins finally made the switch to digital when he finally tried out an Alexa and was pleased with the results. And he obviously has rather high standards. :)

IIRC the first film he shot digitally was SkyFall, using Alexas. He made a comment in one of the articles I read about that film that one of the things he liked about digital was that it was sensitive enough to use just the flames of Skyfall burning down to light the final fight scene.


Another example is Guardian of the galaxy vol 1 that was shot on alexa xt vs vol 2 shot on RED/phantom flex 4k. Did vol 1 look worse? Hell no. Why they ditched alexa for vol2 guardian is a bit of a mystery to me, when you see the quality of the first one. I guess lobbying still works ;)


A lot of it comes down to preference. And in some cases pragmatism; Red cameras are easier on the Steadicam operators than Alexas ;)

They also wanted the extra resolution for the FX folks. That's a big arena for Red, and it's one of the main reasons that Red continues to push resolution; even for films finished in 2K (which is all of them), I've run into several FX folks who've told me that they like the cleaner keys and that sort of thing that they can get with the higher resolution cameras.

Dunkirk , in IMAX 70mm made perfect sense, since they almost went 100% practical effects. IMO the texture/IQ made its own appealing effect. Perfect for that movie.


Part of that was also Chris Nolan's preference for using celluloid -- and the still shot significant parts of that film in 35mm.

There is always time, or not, for high res. Resolution is almost a kryptonite for heavy fx work.


Not at all. Resolution for CG renders is a major holdup, but a lot of VFX work involves keys, object removals, and that sort of thing for which having more resolution in the source footage than you need for mastering turns out to be helpful for delivering cleaner results.
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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostTue Oct 09, 2018 6:51 pm

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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostWed Oct 10, 2018 1:43 am

Thanks, Ulysses, for posting this. If people can’t spare 20 minutes, just go for the life lesson in the last three minutes.


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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostWed Oct 10, 2018 8:12 am

Agreed... well said.

A better camera won't make you a better cinematographer... but there are also a lot of very good cameras available at all sorts of price points.
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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostWed Oct 10, 2018 3:43 pm

Finally, some true arri competition…

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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostWed Oct 10, 2018 7:35 pm

Oyvind Fiksdal wrote:Finally, some true arri competition…



Is that what You think?
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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostWed Oct 10, 2018 8:35 pm

Ulysses Paiva wrote:
Is that what You think?


Think what? This is a bmpcc4k vs alexa thread. As the OP put it. So, yes, I believe this is the closest filmic look we have seen from a official Blackmagic movie.

If you are asking me, “is this like alexa?”, Then the answer is no. Actually, it could be from any camera for that matter. But this time they try to show us a filmic image that you expect from a cinema camera.

Dunno if I like the orange teal look, but that’s a choice they made… The roll off, lowlight and DR look pretty good though.
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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostWed Oct 10, 2018 9:10 pm

Oyvind Fiksdal wrote:
Ulysses Paiva wrote:
Is that what You think?


Think what? This is a bmpcc4k vs alexa thread. As the OP put it. So, yes, I believe this is the closest filmic look we have seen from a official Blackmagic movie.

If you are asking me, “is this like alexa?”, Then the answer is no. Actually, it could be from any camera for that matter. But this time they try to show us a filmic image that you expect from a cinema camera.

Dunno if I like the orange teal look, but that’s a choice they made… The roll off, lowlight and DR look pretty good though.



You think this is the best image BMD has put out so far? I dunno. Sometimes Im sold, sometimes Im not. I guess it has the potential but takes someone to know how to get the best out of it.

In the CVP video It amazed me at first but when it get to the scene with the lighter I felt it was so videoish, like most Sonys. Not a cinematic BMD look. But in the video I posted above with the birds in the lake Ifind it so amazing...
Guess I need much more proper tests.
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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostWed Oct 10, 2018 10:14 pm

Ulysses Paiva wrote:

You think this is the best image BMD has put out so far? I dunno.


Not the best picture, but most cinematic. But then again... we probably need to judge it after seen the whole flick.

I think the bird movie, you refer to, look really good. Its crisp, but not over sharpened, great texture and colour. Like looking at a national geographic shot, which says a lot about the camera’s abilities. Maybe not cinematic IMHO, but not video either. Maybe something like a crisp 16mm, which ironically is used in a lot of nature documentary.
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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostThu Oct 11, 2018 1:27 am

Just to be clear about S16mm look, check the channel of this guy please:


The bird movie looks great but far away from this.
Pocket v1 is more far away to s16mm look to me.
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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostThu Oct 11, 2018 1:37 am

Ulysses Paiva wrote:
Oyvind Fiksdal wrote: Sometimes Im sold, sometimes Im not. .


Me too.....some times not, many times yes just by the price :D
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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostThu Oct 11, 2018 1:42 am

Roberto de la Torre wrote:Just to be clear about S16mm look, check the channel of this guy please:


The bird movie looks great but far away from this.
Pocket v1 is more far away to s16mm look to me.


I think the grain structure plays a big part in the magic. Also good contrast without loosing detail. In fact, I fell the contrast contributes to detailing. Much detail with low sharpness, even smoothness. I dont know. I cant describe technically.
Maybe adding a nice grain in post to the P4k would contribute to the image?
If I had one, I would try it now. I used to do it with motion graphics and 3D to give some organic look and generally it worked well. I used to feel like watching those cinema ads before the trailers starts watching my own stuff on a computer screen with that grain :D

Again, I'm almost sure if you know what you're doing, you could make incredible images with the new pocket. But need to see more content to know better
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Blackmagic Pocket Camera 4K vs Arri Alexa

PostThu Oct 11, 2018 3:12 am

Shooting with the 3200 ISO band instead of ISO 400 may be a desirable aesthetic to approach a grainy Super 16 feel. It has less dynamic range than the ISO 400 band, but again that may help with the higher contrast look if suitably graded since the 3200 ISO band has good shadow range and little highlight room. For a remake of Mr Martyr... ISO 6400 perfect?


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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostThu Oct 11, 2018 5:08 am

You can get grainy high iso like images without loss of dynamic range. This method actually adds dynamic range:
Shoot RAW or ProRes at native ISO800
Monitor histogram/zebra in LOG mode and don't clip any highlights. In high dynamic range scenes image may look slightly dark (underexposed).

Set project input to BMDfilm (or Bypass depending of Color Science mode you want to use for RAW)
Set Timeline to BMDfilm
Set Output to Rec709 (saturation and gamma mapping on) Or you can set it to "Bypass" in project settings and just add Timeline node with Color Space transform Tool Timeline to Rec709 (saturation and gamma mapping on)

Now to recover some hidden dynamic range from shadows in Resolve boost Expose to 1-2 stops. (up to 3 stops with noise reduction. Starting from 4-5 stops FPN in shadows became too visible and color saturation became too low)

Add Gain node and lower the gain to recover clipped data.

Add contrast node because this high dynamic range image may have low contrast semy-log look.

I noticed that Pocket 4K have less FPN and allows more shadows recovery than older cameras but same time noise grows way faster than in older cameras. It also seems have different starting point with lower dynamic range. P4K with recovered 2 stops looks like BMMCC without any recovery.
Sample from Pocket4K:

Image
Image
Image
Image
Image


P.S. I am sorry but none of the Pocket4K sample clips looks like Pocket v1 or film because different sensor and not enough dynamic range. Video with birds filmed and graded well but it have same feeling of slightly not enough dynamic range.
Here are few more grabs from random Pocket v1 and BMMCC camera DNG shared samples to compare:

Image
Image
Image
Image
Image
Image
Image
Image
Image
Image
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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostThu Oct 11, 2018 10:58 am

Ulysses Paiva wrote:
Oyvind Fiksdal wrote:Finally, some true arri competition…



Is that what You think?


I thought this was supposed to come out the 10th? Am i missing something because it's not up anywhere it seems.
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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostThu Oct 11, 2018 12:04 pm

Dmitry Shijan wrote:P.S. I am sorry but none of the Pocket4K sample clips looks like Pocket v1 or film because different sensor and not enough dynamic range


What exactly are random shots culled from the internet, compared telepathically to unrelated BMPCC 4K material also seen on the web, and with a tortured grading workflow (applied retrospectively to BMPCC/BMCCC originals you don't actually possess?), supposed to prove?

I have no idea at this point whether the BMPCC 4K is an advance or a regression, with reference to your stated preferences. But before making this assertion constantly and repeatedly, wouldn't it make sense to actually compare the cameras side by side, with actual footage from both?
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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostThu Oct 11, 2018 12:09 pm

New videos are up, guess I was looking in the wrong place:

https://www.blackmagicdesign.com/au/pro ... ra/gallery
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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostThu Oct 11, 2018 2:18 pm

Sean van Berlo wrote:New videos are up, guess I was looking in the wrong place:

https://www.blackmagicdesign.com/au/pro ... ra/gallery


Nice! I searched too and had found nothing. Thanks!
The youtube video was misleading pointing to BMD YT channel.
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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostThu Oct 11, 2018 4:44 pm

Ulysses Paiva wrote:
Roberto de la Torre wrote:Just to be clear about S16mm look, check the channel of this guy please:


The bird movie looks great but far away from this.
Pocket v1 is more far away to s16mm look to me.


I think the grain structure plays a big part in the magic. Also good contrast without loosing detail. In fact, I fell the contrast contributes to detailing. Much detail with low sharpness, even smoothness. I dont know. I cant describe technically.
Maybe adding a nice grain in post to the P4k would contribute to the image?
If I had one, I would try it now. I used to do it with motion graphics and 3D to give some organic look and generally it worked well. I used to feel like watching those cinema ads before the trailers starts watching my own stuff on a computer screen with that grain :D

Again, I'm almost sure if you know what you're doing, you could make incredible images with the new pocket. But need to see more content to know better


Not sure. I mean, grain helps smoothing digital, but I think the look is more about colors.
I'm sure with a denoise plugin over this 16mm film, getting 0 grain and still looking organic.

Colors make my doubt about BM, Xt-3 and D Bolex, yeah, that hipster overprice camera that could have been a great camera but it was not. Anyway, everything points to P4k and sure I going to buy it
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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostThu Oct 11, 2018 5:39 pm

Sean van Berlo wrote:New videos are up, guess I was looking in the wrong place:

https://www.blackmagicdesign.com/au/pro ... ra/gallery


Thanks,Sean; those new videos are very beautiful each in their own way. The couple reading their vows to each other while it snows, is tender, touching, timeless. They are the luckiest on the planet in that moment together.
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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostFri Oct 12, 2018 11:53 pm

Ok, back. Putting everybody on a diet till the weekend as I had people swirling around with contrary views (each direction) and merely contradicting things. Been extremely bad with tanked ultra low chromium during chemo. So wasn't up to people wasting my life for some neurosis.

There are those with some knowledge who accuse those who figure things out of rambling because they don't recognise figuring out.
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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostSat Oct 13, 2018 12:38 am

Dmitry Shijan wrote:P.S. I am sorry but none of the Pocket4K sample clips looks like Pocket v1 or film because different sensor and not enough dynamic range.


Again, from the few examples I've seen comparing the BMPCC to the Pocket 4K, their dynamic range was either on-par or the Pocket 4K had slightly more.

And for the second time in a row you've claimed that footage you're using in an example is from the Pocket 4K when it's from the Ursa Mini Pro which has 15 (really 14 2/3) stops of dynamic range. That greenscreen footage was shot to test Blackmagic RAW which is only available on the Ursa Mini Pro at the moment. I know because of the have the same footage on my computer. It blows my mind that you would think otherwise when the resolution of that footage is 4608x2592.

Image
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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostSat Oct 13, 2018 12:48 am

Rakesh Malik wrote:
Wayne Steven wrote:But people want to eye pick a few specs that don't describe everything and ramble on how specs can't be trusted, don't trust them. There are words for this I can't use here. There is an avalanche of information in real life, it is a matter of pursuit of discovery to find the truth.


The specs aren't what make for great images. Roger Deakins selected Alexas for Blade Runner 2049 over Alexa 65s, even though he had the choice. If any of your silliness had any merit, he'd have gone with Alexa 65s for the resolution, since Alexas are "only" 3.2K cameras (and that's only when they're open gate -- since he didn't shoot anamorphic, he didn't even use a full 3.2K).

In spite of that, Blade Runner 2049 was absolutely gorgeous... but never just for the sake of looking gorgeous.

So obviously, specs aren't anywhere near the big deal that you or any other spec hounds make them out to be.


michaeldhead wrote:
Rakesh Malik wrote:So obviously, specs aren't anywhere near the big deal that you or any other spec hounds make them out to be.


+1


Your arguments dont have much to do with what was discussed.

70mm film was harder and more expensive to deal with, so wasn't used much. It was used as a quality choice. Same with Alexa's. The guy made a choice with a camera, which would render to the majority of present theatre projectors and could be suitably upscaled to 4k (though not as sharp as Red oversampling obviously).

I thought the point was that Alexa has a high enough quality spec for high end productions with 14.5-16 stops, (depending on the model) and better colour throughout that range?

Specifications are the scientific description of the how the image is picked up, the quality look of the image. So again, I'm not the one rambling.
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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostSat Oct 13, 2018 2:12 am

Wayne Steven wrote:70mm film was harder and more expensive to deal with, so wasn't used much. It was used as a quality choice.


No, it was a stylistic choice due to the format.

I thought the point was that Alexa has a high enough quality spec for high end productions with 14.5-16 stops, (depending on the model) and better colour throughout that range?


14. Arri hasn't changed its pixel design, so all of its cameras render images more or less identically; they have the same color rendition, same response characteristics. A lot of DPs like that about Alexas; it's one of the reasons that Arri hasn't come up with a new pixel design after all these years.

Specifications are the scientific description of the how the image is picked up, the quality look of the image. So again, I'm not the one rambling.


You are, as usual... because there are several cameras out there with more dynamic range and wide color gamut, including Red's newest line (Monstro, Helium, Gemini) and Sony's Venice.

Even some of BMD's cameras have more dynamic range -- specifically the 4.6K models.

And a lot of Hollywood productions mix Alexas, Reds and even Phantoms, taking advantage of Red's resolution for FX shots and Phantoms for extremely high speed photography since Phantoms can reach 1000 fps in 4K (well, some of them).

The look however is far more from art direction and lighting than it is which camera you use, regardless of the specs. Upstream Color looked great, and it was shot on a GH2 or GH3, I've forgotten which; those had quite a bit less than 12 stops of dynamic range... but a good DP can work with that.

So no, you don't NEED 14+ stops of dynamic range and crazy resolution to make great images.

You need talent.
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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostSat Oct 13, 2018 4:12 am

Mark Grgurev wrote:
Dmitry Shijan wrote:P.S. I am sorry but none of the Pocket4K sample clips looks like Pocket v1 or film because different sensor and not enough dynamic range.


Again, from the few examples I've seen comparing the BMPCC to the Pocket 4K, their dynamic range was either on-par or the Pocket 4K had slightly more.

And for the second time in a row you've claimed that footage you're using in an example is from the Pocket 4K when it's from the Ursa Mini Pro which has 15 (really 14 2/3) stops of dynamic range. That greenscreen footage was shot to test Blackmagic RAW which is only available on the Ursa Mini Pro at the moment. I know because of the have the same footage on my computer. It blows my mind that you would think otherwise when the resolution of that footage is 4608x2592.

Image


Yea, my fault. I graded those greenscreen samples in PocketK4 log gamma and gamut and they looked strange.
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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostSun Oct 14, 2018 11:35 am

Hmm, well admittedly I haven't investigated the Alexa sensor because I wasn't going to buy the camera. But looking at their website it uses the exact same simultaneous dual gain idea I advocated, to achieve the 14.5 stops on their large format iso chart (claim 14 stops+ in the specs). I advocated you could trick other dual gain architectures into a similar latitude expansion (but more than this). But no wonder I don't see people touting it on other cameras, Arri could even have a license/patent to make sure they keep their lead.

The issue has been with increasing single gain at a time architecture you see with the Pocket 4k, lattitude reduced with gain. So, while Red might toot peak gain, if you look at the test charts (which equals spec) you see a drop off and the peak is only in part. But Arri proves this that gain is not just a dirty word.

I had read that people were saying over 15.x - 16.x stops on the latest cameras, which I assumed THEY knew what they were talking about. However, even if no pixel design changes, what normally happens is reformulation/refinement of the sensor chip foundary process which can greatly affect performance (which Sony cross licensed with the Micron sensor child company to get). They have not dubens better pixel, and if they can't even afford to reformulate their chip materials, that would be bad. I question why they haven't got to 20 stops yet. The thing about having more consistent 14+ l, and colour, is this spec allows the camera the deliver better images of verba wider set of conditions, where you would get caught out less. I wonder when the patent runs out on the core technologies, I could get a phone like that that's not some newer Sony sensor with large native latitude. You notice how they market the pixel size thing for noise and latitude. Does that indicate that they have the technology to do better (allowing similar performing smaller pixels or better same sized ones)? Sony has been vacuuming up sensor technology and companies for many years. Arri is fortunate they partnered with one company who vacuumed up some of their own, but that does not equate to the ability to come up with more leading technologies. Those companies taken up are a few of my favourites at the time (where I wanted to use their sensors). I did knock on that company's door and advocate doing a cinema sensor with those technologies, I wonder if this was it? Shortly afterwards there was no communication, and in the precise timeframe to do it, the Alexa camera came out afterwards. But that is the way it has often worked in this side of the industry. Those that have do mediocre, and those that could do more don't get access any longer. I should have used that, pre Alexa, small sensor to do a 720p camera rather than trust cough Red, SI, others, to do the right thing. BM is one of the few companies to do so to an extent. Anyway, enough whining about the past and those wedded to high profit margins.

---

Well, looking around I do find people that know what they are talking about, talking about dynamic range over 15 stops (even the Arri spec indicates more than 14 stops). Looks like I was just seeing different people use different definitions of what a stop is overtime. Here is some Inane coversations about it all:

https://www.provideocoalition.com/alexa ... ou_use_it/

This thread here talks about Alexa dynamic range, and will tell you a lot about dynamic range. Phill's pretty ok. He's right on the ball about it being the image and range giving you flexibility and ability to deal with tough real life filming situations. It has other smart people getting their hands technically dirty to understand how to milk the most out of their camera images:

http://www.reduser.net/forum/archive/in ... 15006.html

http://www.reduser.net/forum/archive/in ... 6-p-2.html

(Here is another thread from BMCuser to even things out:
http://www.bmcuser.com/archive/index.php/t-16813.html )

I spend a lot of time listening to far smarter people and those who make new technologies. You could learn a lot. Ask David.
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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostSun Oct 14, 2018 12:24 pm

Why follow around trying to prove wrong what was right, with this tangent about stuff about trying to equate the images between cameras, when it has been stated that hdr etc just makes it easier to match a wider range of styles and deal with difficult shooting. Whatever they do on set with controlled limited lighting (to match the camera limitations) is irrelevant to what you have to do out in the real world of unscripted non fiction, or low budget, filming, which this camera is also aimed at. Read the threads above, it helps on set too. Was the guy wrong that did the YouTube comparison because he thought Alexa was preferable, when he could have put in the effort to make the pocket match? This is mixing up of the formal technical art of trying to match the image, with the real art of the image of the story. If you want to prove, then buy an old 4 or 5 stop camera and make it match and make modern production styles, getting everybody to rush around set to do extra setup to get the camera looking good.

Now, I don't have time to answer twisting and expanding the argument, and repeatedly having to do research to show what I said right was right. I take time and effort to think about what is the correct thing to say beforehand anyway.
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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostMon Oct 15, 2018 5:51 am

Wayne Steven wrote:Hmm, well admittedly I haven't investigated the Alexa sensor because I wasn't going to buy the camera. But looking at their website it uses the exact same simultaneous dual gain idea I advocated, to achieve the 14.5 stops on their large format iso chart (claim 14 stops+ in the specs). I advocated you could trick other dual gain architectures into a similar latitude expansion (but more than this). But no wonder I don't see people touting it on other cameras, Arri could even have a license/patent to make sure they keep their lead.

The issue has been with increasing single gain at a time architecture you see with the Pocket 4k, lattitude reduced with gain. So, while Red might toot peak gain, if you look at the test charts (which equals spec) you see a drop off and the peak is only in part. But Arri proves this that gain is not just a dirty word.


Don't forget that some older cameras (BMCC, BMPCC, BMMCC, 4.6K) use dual gain sensors made by BAE/Fairchild Imaging. They are similar to Arri. That's why noise structure and dynamic range looks so different in those cameras. My guess that dual gain is more complicated and may needs more cooling, more bandwidth and more processing power than common single gain sensor.
BAE/Fairchild Imaging is industrial/military company so probably they have less requirements in quality supply control level. I think BM sacrifice some specs and choose Sony sensor only because it is simpler and provides more stability in supply and quality control. BTW BAE/Fairchild Imaging have dual gain M4/3 4K sensor in datasheets long time ago, but it is not on their website probably because not manufactured yet, probably because they just can find a proper market for this product.
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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostMon Oct 15, 2018 12:17 pm

Didnt know first cameras were dual gain. Or even that ahead chip tech as you say. Anyway, it just adds to my vision that BMCCs were (still are) very underestimated/ignored cameras.
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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostMon Oct 15, 2018 2:35 pm

Wayne Steven wrote:Hmm, well admittedly I haven't investigated the Alexa sensor because I wasn't going to buy the camera. But looking at their website it uses the exact same simultaneous dual gain idea I advocated, to achieve the 14.5 stops on their large format iso chart (claim 14 stops+ in the specs). I advocated you could trick other dual gain architectures into a similar latitude expansion (but more than this). But no wonder I don't see people touting it on other cameras, Arri could even have a license/patent to make sure they keep their lead.

Take a look at the Z CAM E2, which uses a Sony sensor technology (WDR) to yield a 16 stop exposure. The visual error when the subject moves too much looks like old school motion blur, so it's not as objectionable as some other methods.
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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostMon Oct 15, 2018 2:45 pm

Some cameras lean into an obvious "look." This seems to be Arri's approach in emulating film response.

Some cameras strive to be as "transparent" as possible. This seems to be RED's strategy.

Many times, the aesthetic of a camera is defined more by its limitations than its strengths. I'm convinced this is the case with the fetishizing of the original Pocket.

One approach isn't inherently better than the other. It depends how you prefer to work. But this is true: It is possible to degrade a technically superior signal to match an inferior (but pleasing) image, but it is very difficult (to impossible) to improve a technically inferior signal to match a superior image. You can lower DR in post. You can lower detail in post. You can't do the reverse. (Though sometimes you can credibly fake it.)
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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostMon Oct 15, 2018 2:52 pm

Rakesh Malik wrote:
Wayne Steven wrote:70mm film was harder and more expensive to deal with, so wasn't used much. It was used as a quality choice.

No, it was a stylistic choice due to the format.

It's disingenuous to imply that the practical implications of a format don't impact the decision of what camera system to use. There are directors that could should every minute of their movie on IMAX film if they wanted to, but they recognize it would be production hell. Most people don't resort to a GoPro for the aesthetic - they use it `cause it will actually fit where it needs to go, or they can afford to destroy it.
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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostMon Oct 15, 2018 7:53 pm

Dmitry Shijan wrote:Don't forget that some older cameras (BMCC, BMPCC, BMMCC, 4.6K) use dual gain sensors made by BAE/Fairchild Imaging. They are similar to Arri. That's why noise structure and dynamic range looks so different in those cameras. My guess that dual gain is more complicated and may needs more cooling, more bandwidth and more processing power than common single gain sensor.


Well yes. When you're simultaneously reading from two gain circuits and then combining the results then it makes a lot of sense that it would use more power. From what I can tell, those Fairchild sensors worked was by literally having two ADCs.

Dmitry Shijan wrote:I think BM sacrifice some specs and choose Sony sensor only because it is simpler and provides more stability in supply and quality control.


Your bias is definitely showing again. What makes you think they're sacrificing anything? The fact that Fairchild's sensors needed to combine the results from two gain circuits to get 13-ish stops of dynamic range means that their photosites aren't capable enough to do that by themselves. There's a reason why Sony sensors are used in Nikon, Sony, Panasonic, Kinefinity, Z-Cam, and now Blackmagic cameras as well as huge amount of smart phones. They're good at making sensors.

Does that mean that I'm saying Fairchild/BAE, Aptina, or CMOSIS sensors are bad? No. They produce great images but having to combine the result of two gain circuits is a brute force way of doing things and is not overall superior. The fact that Sony's sensor is giving the Pocket 4K seemingly better dynamic range than the original Pocket with a pixel pitch smaller than any of the previous sensors used in BMD cameras shows that it's really good sensor.
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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostMon Oct 15, 2018 11:43 pm

Mark Grgurev wrote:Your bias is definitely showing again. What makes you think they're sacrificing anything? The fact that Fairchild's sensors needed to combine the results from two gain circuits to get 13-ish stops of dynamic range means that their photosites aren't capable enough to do that by themselves. There's a reason why Sony sensors are used in Nikon, Sony, Panasonic, Kinefinity, Z-Cam, and now Blackmagic cameras as well as huge amount of smart phones. They're good at making sensors.


That is the crux. Sony makes some of the world's best sensors. Even Fuji uses Sony sensors in its medium format cameras, and Phase One and Hasselblad both use Sony sensors. So does DJI in most of its drones, even the model that has a Hasselblad camera.

Does that mean that I'm saying Fairchild/BAE, Aptina, or CMOSIS sensors are bad? No. They produce great images but having to combine the result of two gain circuits is a brute force way of doing things and is not overall superior. The fact that Sony's sensor is giving the Pocket 4K seemingly better dynamic range than the original Pocket with a pixel pitch smaller than any of the previous sensors used in BMD cameras shows that it's really good sensor.


I believe that the dual gain method has more to do with not having BSI sensors available. Sony was one of the first to figure out how to make those in volume, and the only sensor manufacturer so far that has been able to scale up BSI (and stacked chips) for volume production in larger sizes, now all the way up to medium format.

BSI might not sound all that exciting, but for light gathering capability, it's a big deal on top of being a bear to manufacture.
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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostMon Oct 15, 2018 11:52 pm

Your bias is definitely showing again. What makes you think they're sacrificing anything? The fact that Fairchild's sensors needed to combine the results from two gain circuits to get 13-ish stops of dynamic range means that their photosites aren't capable enough to do that by themselves. There's a reason why Sony sensors are used in Nikon, Sony, Panasonic, Kinefinity, Z-Cam, and now Blackmagic cameras as well as huge amount of smart phones. They're good at making sensors.

Does that mean that I'm saying Fairchild/BAE, Aptina, or CMOSIS sensors are bad? No. They produce great images but having to combine the result of two gain circuits is a brute force way of doing things and is not overall superior. The fact that Sony's sensor is giving the Pocket 4K seemingly better dynamic range than the original Pocket with a pixel pitch smaller than any of the previous sensors used in BMD cameras shows that it's really good sensor.


"Good" or "bad" are really strange worlds for digital sensors. There are different sensors and different situations they used. Some people OK with lower dynamic range some not. Fairchild/BAE sensors have less noise and more uniform film grain-like noise structure, but also have FPN problems in deep shadows. CMOSIS are industrial global shutter sensors with low dynamic range and FPN. Sony have almost no FPN, but its noise structure looks very "ugly digital", similar to any other single noise sensor (including RED cameras). That's why i believe it have slightly less dynamic range than dual gain sensors.
Here are some nice low light Pocket4K tests https://www.youtube.com/user/Jsfilmz/videos and shared DNGs in Youtube comments so anyone can check and compare noise looks.
Why most other cameras use single gain sensors? Probably because that technology is cheaper and simpler for high megapixel still cameras. Why Arri use dual gain sensor? Probably because they want to be a best respected film looking camera in the world.
If BM PR manager tell you that both cameras have average 13 stops of dynamic range it is not always means that cameras are really the same.
BM don't choose to be as stable and uniform as Arri. They choose to mix a lot of different sensor variations in different cameras and never do a 100% perfect camera. This is i really don't like in this company. They could make less camera variations but do them all with better quality and ergonomics and only with Fairchild/BAE dual gain sensors with better in-camera FPN filtering.
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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostTue Oct 16, 2018 1:13 am

Dmitry Shijan wrote:Fairchild/BAE sensors have less noise and more uniform film grain-like noise structure, but also have FPN problems in deep shadows.
Sony have almost no FPN, but its noise structure looks very "ugly digital", similar to any other single noise sensor (including RED cameras). That's why i believe it have slightly less dynamic range than dual gain sensors.


You're absurd. For one, the noise on my original Pocket is anything but uniform. The top of the frame is always noisier than the bottom because there's something on the bottom of the sensor that's giving off heat that's not being pushed away.

There's not such thing as a "digital" looking noise. Sensors are analog so all of them have analog looking noise because it IS analog noise. If you mean more like film the grain of film then that too is wrong. All sensors produce chroma noise you won't find in film and grain appears more evident in brighter parts of the image while noise is more evident in darker parts.

And regardless of what your opinion of noise the noise structure is, the Sony sensors are less noisy overall which would be reason to believe they have a higher dynamic range, not lower.

Dmitry Shijan wrote:Here are some nice low light Pocket4K tests https://www.youtube.com/user/Jsfilmz/videos and shared DNGs in Youtube comments so anyone can check and compare noise looks.


Those are comparing noise from the same exact sensor just used in two different cameras. The Pocket 4k doesn't have in-camera noise reduction while the GH5s does so you get a different look.

Dmitry Shijan wrote:Why most other cameras use single gain sensors? Probably because that technology is cheaper and simpler for high megapixel still cameras. Why Arri use dual gain sensor? Probably because they want to be a best respected film looking camera in the world.


Again, a huge jump in logic. Just because Arri does it, doesn't mean it's the better way to do something. Arri's been using the same sensor since 2010. There were not a whole lot of single gain sensors reaching even 13 stops of dynamic range at the time so dual gain would have been the way to increase DR at the time.

Dmitry Shijan wrote:If BM PR manager tell you that both cameras have average 13 stops of dynamic range it is not always means that cameras are really the same.


I've said this three times at this point. I've seen multiple comparisons of BMMCC and the Pocket 4K and the Pocket 4K appears to have more dynamic range yet both cameras were advertised as having 13 stops of DR. Clearly I'm not just making assumptions based on specs.

Dmitry Shijan wrote:This is i really don't like in this company. They could make less camera variations but do them all with better quality and ergonomics and only with Fairchild/BAE dual gain sensors with better in-camera FPN filtering.


No they really shouldn't. They should continue to use the sensors they feel are best suited for each camera.
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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostTue Oct 16, 2018 1:49 am

I'll post these images one more time. Both processed in similar workflow (LOG timeline, 2 to 5 stops expose boost, lower gain and with Kodak64 film emulation LUT in some samples). Open images in 100% size. Even scaled to HD P4K is noisier
Pocket camera have Chroma noise which is VERY easy to remove, but same time because dual gain Luma noise very low.

P4K:
Expose2 (ISO5000), Gain adjust, CST node LOG to Rec709, K64 flm emulation LUT
Image
Expose2(ISO5000), Gain adjust, CST node LOG to Rec709, K64 flm emulation LUT
Image
Expose2(ISO5000), Gain adjust, CST node LOG to Rec709, K64 flm emulation LUT
Image
Expose5 (ISO40000), Gain adjust, CST node LOG to Rec709, K64 flm emulation LUT
Image

BMPCC/BMMCC (MORE TESTS HERE viewtopic.php?f=21&t=65149 )
Image
Image
Image
Image
Image
Image
Image
Image
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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostTue Oct 16, 2018 2:37 am

Dmitry Shijan wrote:I'll post these images one more time. Both processed in similar workflow (LOG timeline, 2 to 5 stops expose boost, lower gain and with Kodak64 film emulation LUT in some samples). Open images in 100% size. Even scaled to HD P4K is noisier
Pocket camera have Chroma noise which is VERY easy to remove, but same time because dual gain Luma noise very low.


Why do you constantly try to draw conclusions between these two cameras by showing how they perform in completely different scenarios. If you want to make a case for these things then show the BMPCC/BMCC side by side with a Pocket 4K shooting the same thing.

In one example you keep posting, the sky is already blue before you pushed the exposure in post and the people in the shot are wearing down jackets which means it was cold. So it wasn't that dark to begin with and the sensor was kept cool which keeps the image cleaner. If you did the same test an hour or two later and during the summer, FPN would have reared it's ugly head, the noise floor would have increased, and you probably would have seen some hot pixels.

That's why controls are important.
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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostTue Oct 16, 2018 3:26 am

I'll be happy to do side by side test but i don't have Pocket 4K camera. So i try so use similar samples from online reviews and from my personal BMMCC footage.
:arrow: If someone have both cameras please shoot few samples in high dynamic range situation so we can stop speculate around this question. During test don't try to match expose by middle grey level or by skin tones, just expose both cameras in native ISO in LOG WITHOUT highlights clipping. So anyone can process them in similar workflow and compare how deep both cameras see into shadows, what dynamic range starting point they both have and which noise type is easer to remove.
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Re: Blackmagic Pocket Camera 4K vs Arri Alexa

PostTue Oct 16, 2018 4:36 pm

Dmitry Shijan wrote:
Wayne Steven wrote:Hmm, well admittedly I haven't investigated the Alexa sensor because I wasn't going to buy the camera. But looking at their website it uses the exact same simultaneous dual gain idea I advocated, to achieve the 14.5 stops on their large format iso chart (claim 14 stops+ in the specs). I advocated you could trick other dual gain architectures into a similar latitude expansion (but more than this). But no wonder I don't see people touting it on other cameras, Arri could even have a license/patent to make sure they keep their lead.

The issue has been with increasing single gain at a time architecture you see with the Pocket 4k, lattitude reduced with gain. So, while Red might toot peak gain, if you look at the test charts (which equals spec) you see a drop off and the peak is only in part. But Arri proves this that gain is not just a dirty word.


Don't forget that some older cameras (BMCC, BMPCC, BMMCC, 4.6K) use dual gain sensors made by BAE/Fairchild Imaging. They are similar to Arri. That's why noise structure and dynamic range looks so different in those cameras. My guess that dual gain is more complicated and may needs more cooling, more bandwidth and more processing power than common single gain sensor.
BAE/Fairchild Imaging is industrial/military company so probably they have less requirements in quality supply control level. I think BM sacrifice some specs and choose Sony sensor only because it is simpler and provides more stability in supply and quality control. BTW BAE/Fairchild Imaging have dual gain M4/3 4K sensor in datasheets long time ago, but it is not on their website probably because not manufactured yet, probably because they just can find a proper market for this product.


I didn't know that Dmitry. I saw that most all the older cameras didn't have what I was after and so didn't look into them. Besides, somebody here authoritively told me that BM doesn't use gain on the mini and that's why it produced such great images. I am a sucker.

However, dual gain non simultaneously is normal. I heard in the past Sony gets high native range (12stop+) on consumer cameras without using two gains. Do you know for certain these cameras have simultaneous gain?
aIf you are not truthfully progressive, maybe you shouldn't say anything
bTruthful side topics in-line with or related to, the discussion accepted
cOften people deceive themselves so much they do not understand, even when the truth is explained to them
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