Crop factor 2.4 : how is possible have wide lenses ?

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Gabriele Turchi

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Crop factor 2.4 : how is possible have wide lenses ?

PostThu Aug 30, 2012 10:01 am

With a crop factor of 2.4 even the tokina @11mm become a 26mm ...

is there anything wider available (no distortion ) ...?

or someone from BMD know about any company (like tokina) that are working on a wide lens for this sensor ...

the 2.4 crop factor is actually the major reason for me the old the purchase

thanks a lot

g
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Sandy Campbell

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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostThu Aug 30, 2012 10:31 am

As the BMCC also accepts EF-S lenses, why not consider this range of glass as the form factor drops to approx 1.6, making your example of the Tokina 11-16mm very useful indeed.

Aleksandr_Oleynik

Re: Crop factor 2.4 : how is possible have wide lenses ?

PostThu Aug 30, 2012 2:15 pm

With EF-S lenses Crop factor for BM will not drops! It will be the same 2.4
Tokina 11-16mm will be 26-38 mm
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Loïc Surprenant

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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostThu Aug 30, 2012 2:40 pm

The only way to go really wide with this kind of small sensor is to have an anamorphic adapter on your lenses. But since it's a 16:9 sensor, you will lose 1/3 of your image by cropping the sides to a 2:85 ratio. The best solution in this situation would be to have a full read of the sensor if it's 4/3. Or wait and buy the digital bolex wich will have a 4/3 full read for anamorphic. But when will this camera be ready? Who knows.
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Hans Engstrom

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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostThu Aug 30, 2012 3:44 pm

Talking about a cropfactor of 2.4 is silly. I work as a 1st AC and compare everything to 35mm film, 16mm film or s35mm sized sensor (I have never worked with 65mm or 5Ds on features). It´s rare to have anything wider than a 16mm lens in your case when shooting s35. The cropfactor compared to s35 is close to 1.6 which means that a 10mm is as wide as you normally go on the BMCC. Sure, on some special shots I have used a 8mm Peleng but I can count thoose times on the fingers on my right hand.

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Peter J. DeCrescenzo

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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostThu Aug 30, 2012 7:19 pm

The BMCC’s field of view crop factor compared to S35 16:9 motion picture formats is 1.6. So, for example, using the wide end of a Tokina 11-16mm f2.8 zoom the FOV is equiv. to about a 18mm on S35 16:9. S35 filmmakers don’t typically shoot much wider than that.

There’s also the slower Sigma 8-16mm zoom, a rectilinear super-wide; at the wide end its FOV is equiv. to about 13mm on S35 16:9.

Of course, there are excellent wides made by Canon & others, too. Perhaps Canon will offer new super-wides partly due to the BMCC’s likely success.

See also:
http://www.abelcine.com/fov/
Last edited by Peter J. DeCrescenzo on Fri Aug 31, 2012 12:42 am, edited 2 times in total.
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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostThu Aug 30, 2012 8:18 pm

Thu Aug 30, 2012 2:15 pm
With EF-S lenses Crop factor for BM will not drops! It will be the same 2.4
Tokina 11-16mm will be 26-38 mm


Why the crop factor not affected by a non-full frame
Lense??

Whats the differences from aps-c sensor?
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rick.lang

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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostThu Aug 30, 2012 8:21 pm

Loïc Surprenant wrote:The only way to go really wide with this kind of small sensor is to have an anamorphic adapter on your lenses. But since it's a 16:9 sensor, you will lose 1/3 of your image by cropping the sides to a 2:85 ratio. The best solution in this situation would be to have a full read of the sensor if it's 4/3. Or wait and buy the digital bolex wich will have a 4/3 full read for anamorphic. But when will this camera be ready? Who knows.


I think you're considering a 2x anamorphic adapter with these calculations. An anamorphic lens that has a multiplier of 1.3 to 1.35 would be better, without losing any of the image.
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Peter J. DeCrescenzo

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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostThu Aug 30, 2012 9:28 pm

Seaborn wrote:... Whats the differences from aps-c sensor?


The FOV of APS-C is very close to S35 16:9 motion picture formats. See my post above for more info.

See also:
http://prolost.com/storage/post-images/ ... 5660764902

http://www.abelcine.com/fov/
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Marco Solorio

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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostFri Aug 31, 2012 12:27 am

Hopefully my latest blog post will subdue all concerns shooting wide on the Cinema Camera. Yes, it can be done, and it looks great.

http://www.onerivermedia.com/blog/?p=677

Cheers!
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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostSat Sep 01, 2012 5:27 am

The FOV of APS-C is very close to S35 16:9 motion picture formats. See my post above for more info.


Thanks, this tool is awesome!
But i still have a question

I'm planing to buy a 8mm lens
If i buy one as full frame i get +- a 18mm with the crop factor
But if i buy a 8mm lens for aps-c does i get a +- 13mm with the crop factor
Maybe i'm wrong... The 2.3x crop factor is calculated in as:
full frame=1x
Aps-c=1.6x
Bmc=2.3x
I dont have any aps-c lens and this confusing me...
Excuse my english.
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Hans Engstrom

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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostSat Sep 01, 2012 10:01 am

Seaborn wrote:
The FOV of APS-C is very close to S35 16:9 motion picture formats. See my post above for more info.


Thanks, this tool is awesome!
But i still have a question

I'm planing to buy a 8mm lens
If i buy one as full frame i get +- a 18mm with the crop factor
But if i buy a 8mm lens for aps-c does i get a +- 13mm with the crop factor
Maybe i'm wrong... The 2.3x crop factor is calculated in as:
full frame=1x
Aps-c=1.6x
Bmc=2.3x
I dont have any aps-c lens and this confusing me...
Excuse my english.


A 8mm lens will allways be a 8mm lens. The FOV changes depending on how big the sensor is, the crop factor is just how much of the "projection" from the lens your sensor will use. 8mm for APS-C and full frame format are made for bigger sensors and are capable of delivering bigger FOV but will not do so on BMC.

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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostSat Sep 01, 2012 11:47 am

well, the crop factor / FOV issue is a pretty confusing one for me.
I found this tool very very helpful in order to sort all this thing out

http://www.abelcine.com/fov/
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Noel Sterrett

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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostSat Sep 01, 2012 12:25 pm

The problem isn't crop factor, it's depth-of-field.

In order to have the same field-of-view, the lens of the BMCC needs to be wider by a factor of 2.4. So, for example, a 50mm lens on a FF camera becomes a 22mm on the BMCC.

But in order to achieve the same depth-of-field, the aperture of the BMCC lens must be opened up by around 3 f-stops (see chart)!

So in order to duplicate the shallow depth-of-field of a 50mm f1.2 lens, the BMCC would require:

For Full Frame: 22mm ~f0.42
For Super 35: 31mm ~f0.5

Clearly, there are ~31mm and ~22mm lenses available, but I don't recall seeing any lenses with apertures less than f1.0 advertised lately.

That is why I'm not surprised that none of the Blackmagic Cinema Camera images I have seen so far display the shallow DoF we are so accustomed to seeing in cinema (Citizen Kane excepted).

The workaround (which we did in the early 2/3" HD days) is to back up and use a longer lens. But that presents obvious problems shooting in tight spaces, and tends to impart a distant, telephoto feel to the shot.

It's a great camera. It just needs a great lens. My kingdom for a lens...

Cheers.
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Hans Engstrom

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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostSat Sep 01, 2012 3:10 pm

Some shots calls for short DOF some calls for more DOF. I don't see the sensor size as a big drawback (not saying that I wouldnt have prefered a s35 sized sensor). Shooting wide open is rare on features so I don't think the difference is that important, more important for me is that I get a picture that can take some manipulation and that have some latitude to begin with.

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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostSat Sep 01, 2012 4:10 pm

Thank for clarification.
I will ask my question a different way:

Wich of this lens will give the widest picture on the BMCC:

10mm designed for full frame
or
10 mm designed exclusively for aps-c
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rick.lang

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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostSat Sep 01, 2012 5:16 pm

Noel Sterrett wrote:The problem isn't crop factor, it's depth-of-field.

In order to have the same field-of-view, the lens of the BMCC needs to be wider by a factor of 2.4. So, for example, a 50mm lens on a FF camera becomes a 22mm on the BMCC.

But in order to achieve the same depth-of-field, the aperture of the BMCC lens must be opened up by around 3 f-stops
The workaround (which we did in the early 2/3" HD days) is to back up and use a longer lens.
It's a great camera. It just needs a great lens.


Joel, the 'crop factor' multiplier is not 2.4; it's now about 2.27 after BMD revised their published active sensor (calculated by others and I'm assuming it's true). You merely need to apply that crop factor to the focal length and the aperture to get the equivalent settings for the BMCC (where it can be done as you pointed out).

You're right for very wide open apertures on a larger sensor, the BMCC can't match it for the same DOF and FOV. But it's not quite as bad as saying you need to open up about 3 stops when it's about 2 1/3 stops, i.e.. closer to 2 stops. In practice, this means a fast lens on the BMCC like the f1.4(t1.5) lenses from Rokinon (Samyang) will just about match a full-frame sensor's lens' DOF at f2.8 or more accurately f3.2.

The chart you included has a circle of confusion of 0.03mm but that's for standard 35mm frame size. The circle of confusion for the BMCC is 0.030/2.27=0.0132mm.

Here's a great web site for depth-of-field calculations:
http://www.dofmaster.com/dofjs.html.

I verified the DOF calculator in terms of my camera since there's no listing there for a camera with CoC like the BMCC. It did demonstrate to me though you don't need a chart or online calculator to determine the change in f-stop.

Let's compare FOV and DOV to the the Canon 5D (full frame) with the BMCC ('crop factor' 2.27) assuming a 50mm lens on the Canon and an exposure of f4 for arguments sake since I also don't know any lenses that go below f.095 (the Voitlander lens). Here's the adjustments to get about the same FOV and DOF on the BMCC with the subject at 10 feet:

Canon 5D 36mmx24mm crop 1.0 50.0mm lens f4.00 DOF=2.94 feet
Canon 7D APS-C sensor crop 1.6 ~31.4mm lens f2.50 DOF=2.99 feet (the f4 value divided by crop factor)
BMCC 15.81mm x 8.88mm crop 2.27 22.0 mm lens f1.76 DOF~2.9 feet (open up about 2 1/3 stops)
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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostSat Sep 01, 2012 5:19 pm

Seaborn wrote:Thank for clarification.
I will ask my question a different way:

Wich of this lens will give the widest picture on the BMCC:

10mm designed for full frame
or
10 mm designed exclusively for aps-c


The 10mm lenses will both give the same FOV on the BMCC, equivalent to the FOV of 23mm on the full-frame camera or 16mm on the APS-C camera.
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Noel Sterrett

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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostSat Sep 01, 2012 6:08 pm

rick.lang wrote:Canon 5D 36mmx24mm crop 1.0 50.0mm lens f4.00 DOF=2.94 feet
Canon 7D APS-C sensor crop 1.6 ~31.4mm lens f2.50 DOF=2.99 feet (the f4 value divided by crop factor)
BMCC 15.81mm x 8.88mm crop 2.27 22.0 mm lens f1.76 DOF~2.9 feet (open up about 2 1/3 stops)


I realize the numbers were not exact (I was curious if anyone would notice). But whether it's 2.4 or 2.277, the point remains.

Shallow depth-of-field is widely (sometimes too widely) used as a cinematic tool. And you won't be able to duplicate the look of a wide open Zeiss Master Prime for any amount of money on the BMCC, even if Zeiss offered a Canon mount. It's physics.

So while at first glance, the camera seems a great bargain, the cost of outfitting it with rather specialized lenses which in reality are of marginal use on other cameras could easily tip the scales.

Imagine if the camera had the same number of pixels, but they were just a little bit bigger.

Cheers.
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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostWed Sep 19, 2012 12:19 am

Using EF-S lenses is the same as APS-C format. Using these lenses with form factor of 1.6 is quite acceptable. The range and availability of EF-S lenses is considerable and starting from $50.
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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostWed Sep 19, 2012 2:58 am

Seaborn asks..

"Which of this lens will give the widest picture on the BMCC:

10mm designed for full frame
or
10 mm designed exclusively for aps-c"


Whether you use an EF 10mm or EF-S 10mm.. or a third party 10mm lens on the BMCC.. the FOV is exactly the same. a 10mm lens is a 10mm lens.. the only difference is the quality of lens build/glass.. and of course the price.

So if you put a 10mm lens (no matter EF/EF-S/3rd party) on the BMCC it will equal roughly 23mm on a Full-frame camera.

I hope that clears it up for you.
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Valeriu Campan

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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostWed Sep 19, 2012 3:02 am

Loïc Surprenant wrote:Or wait and buy the digital bolex wich will have a 4/3 full read for anamorphic. But when will this camera be ready? Who knows.


Maybe before BM starts shipping all the pre-orders.
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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostWed Sep 19, 2012 4:16 am

Richard Wade wrote:
Noel Sterrett wrote:The problem isn't crop factor, it's depth-of-field.


The solution is time.

The BMCC is basically the "VX-1000" of next generation cameras. Give it 2-3 years and
much larger/full-frame (possible) sensors can/will appear on either the next version
of the BMCC or a competitor will do it.

Buying fisheye lenses just to get a basic wide is a real waste of money.

I've shot TONS of stuff in my life...and only onetime used a fisheye (and lived to regret it).

The BMCC in essence is making a lot of people make poor/stupid lens choices, when
in reality they should be buying better glass.

Once larger sensors starts shipping on SSD based cameras: You'll see fisheye lenses
skyrocket for sale on ebay.


In the meantime, use a DSLR to shoot your wides, and a BMCC for...

...for what?

We still have yet to see a real greenscreen test on that camera!!!


Hi Richard: From my post "BMCC 'limitations' (not!)":
viewtopic.php?f=2&t=660

===================

The BMCC is “only” able to shoot scenes with a “wide” field of view equivalent to a ~18mm lens on a S35 16:9 motion picture camera — considered “wide” in most movies & TV shows — if the BMCC is fitted with a lens such as the <$700 Tokina 11-16mm f2.8 rectilinear zoom, ...

... Or, a FOV equiv. to using a 13mm lens on S35 16:9 (crazy wide!) if using a <$700 Sigma 8-16mm rectilinear zoom.

The BMCC m43 version “only” has additional wide lenses available for use with it.

Clearly it’s not practical or affordable to shoot “wide” with the BMCC!

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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostWed Sep 19, 2012 8:20 am

Strikes me that there are two camps here, on one side there's those that have been used to working on 35mm and Super16 and their modern equivalents and on the other side there's the people who've grown up with 5Ds.

The reality is that those who've been shooting with a 16-35mm 2.8 zoom on a 5D and want to get the same look on a BMCC aren't going to be happy, whereas those who've always been happy with an 18mm on 35mm aren't going to have an issue.

Like a previous poster said, in all my years as an assistant I never did a job on Vistavision or 65mm and for me the comparison with FF is a little odd, but I can understand it isn't if you're used to a FF sensor. I think of it in terms of it's comparison with film formats and so for me the use of wides and depth of field isn't really an issue with this camera. To me it feels like the BMCC has similar depth characteristics to 35mm film, modern cameras have a lot less depth than film even thought they have similar 'sensor' size. Film had a certain amount of 'give' which critical digital sensors just don't have.

When the RED, D20 and Genesis first appeared all of us 1st ACs had to seriously up our game as the tolerances became so critical, it was suddenly like you were working on anamorphic all the time. For those hankering for the '1.3 on a Master Prime' look I'd recommend a couple of week pulling focus on a TV drama, you'll soon be talking about just how good things look at 5.6.

I'm going to be happy with a Tokina 11-16, if I can shoot at 2.8 it looks about right to me; for a lot of others it isn't going to be the case. Fact is, you're going to be able to make cinematic images with this camera, that has already been proven.
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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostWed Sep 19, 2012 8:28 am

Richard Wade wrote:We still have yet to see a real greenscreen test on that camera!!!


There are tons of greenscreen tests out there. John Brawley has posted some footage on his blog. You can see a quick key I did in Nuke here:

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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostWed Sep 19, 2012 8:39 am

Here is is Field Of View Comparator between Black Magic Cinema Camera and full frame sensor.
At 10mm Lens see the deference. Black magic with Crazy Crop Factor. :cry:
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Luke Armstrong

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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostWed Sep 19, 2012 9:13 am

Richard, please see two posts above......If this isn't what you're after then please tell us what you define as a 'real' greenscreen test.

Luke Armstrong wrote:Richard Wade wrote:
We still have yet to see a real greenscreen test on that camera!!!


There are tons of greenscreen tests out there. John Brawley has posted some footage on his blog. You can see a quick key I did in Nuke here:



If that isn't enough for you, then see the collection of tests here... https://vimeo.com/groups/blackmagic
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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostWed Sep 19, 2012 9:26 am

Just a little further clarification on the whole field of view thing, the FOV comparator doesn't really represent what you'd get if you put a 10mm on a 5D vs a Blackmagic. It does show relative cropping but the image is a little misleading. The shot they've used looks more like a 24ish on the left to my eye and hence very close to what you'd get at 10mm on a BMCC. The shot on the right is a hell of a lot longer than 10mm, more like a 50mm.

A 10mm on a 5D looks more like this http://www.flickr.com/photos/fsgallery/7759115926/ which you aren't going to get on a BMCC, but very few people will ever need it.

I'm not saying the comparison isn't valid I'm just trying to reassure people that you won't need to move halfway across the city just to get a wide ...
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Luke Armstrong

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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostWed Sep 19, 2012 9:30 am

Richard Wade wrote:That's not a green screen test, Why didn't Brawley include a shot of the guy waving his hand
at various speeds? Brawley probably shot that, but opted not to post it because he realized it would
'make BMD look bad'

That's why I don't trust these 'camera reviewers', what they pass off as 'raw footage' actually
went through a lot of post-production/editing. All what we get are highly polished/tested
'fake-raw' just to help pimp their blog/resume.

This is the only "real" BMCC Green screen test to date:



Summary: Brawley's tests are not complete. I want to see movement.
I want to see all the 'errors' which would make most keying compositors break out in
a cold sweat. That way we can see how the BMCC deals with the usual keying issues.


Richard...Claimsfour...

I have told you twice and I'll tell you again. NO camera will get great motion blur with a one click key. It takes a lot of man hours of frame by frame paint to get great motion blur. Period. I'm speaking from experience on films for Cinema release, where nothing is skimped on, they have the best kit and it still takes a lot of work.

You've seen the shot of someone waving their hand - it looked bad. It will do. Thats what Alexa/35mm looks like when you key it.

What do you expect? You seem to have impossible expectations.

Let me put this another way. I COULD take the shot already available of the subject waving her hand, and I COULD put the work in to make it look great, but it will not be a test of the BMCC -we know that we can finesse greenscreen keys - be it from the Iphone or from the Alexa.

The 'errors' you're talking about are naturally occurring... Semi transparent motion blur on a constant brightness greenscreen will translate to dark motion blur on a varied brightness background if the luminance isn't exactly the same in the spot where the motion blur occurs.
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Martin Scanlan

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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostWed Sep 19, 2012 9:57 am

Yeah Luke, what do you know about anything with all your compositing credits on massive features and all that experience working at top end post houses alongside some of the best people in the business?

Weren't we talking about crop factor?
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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostWed Sep 19, 2012 9:58 am

For me it is wierd to read about people complaining this and that.

DSLR filming is just so bad that BMCC is like sun in hell. If you start grading h264 from dslr
you will hate it instantly. Period.

So if you have to buy glass or do something differently so what?

You can now buy HD real camera bodys with biger sensor and uncompressed recorder to it
but guess what no where near 3k price tag. 10 to 20 is more like it.

So people try not complain and be happy what you get for 3k.

You can go out any time and buy 20 k camera already now!
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Luke Armstrong

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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostWed Sep 19, 2012 10:04 am

Richard, cool down with the personal jibes.

You're missing the point here - to expect the BMC to be BETTER than a £80,000 Alexa is totally ridiculous by anyone's standards. I'm not a BMC fanboy, and I don't really care whether you're convinced by the BMC or not.

What does wind me up though, is that you demand people provide tests and when they do, you say the tests aren't good enough............... The tests seem to show what you want them to show - that the BMC is not up to your standards.

The truth about what exactly? The truth is there! Did you try keying it yourself? It keys just fine. No one is lieing to you, there is no cover up.

I don't need to go on videocopilot as I have followed Andrew Kramer for many years - but I don't use After Effects, I use Nuke - which is the industry standard for digital effects for CINEMA - which is what we're talking about here!

I never made any excuses for that test.... I just said it was badly keyed, which it is. He's not a professional and I would have no problem with that footage if I were asked to use it.

There is nothing wrong with the footage................ Its pretty good compared to the stuff I've dealt with in the past. This is the sort of thing that would make me wince: http://www.fxguide.com/wp-content/uploa ... e.0057.jpg
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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostWed Sep 19, 2012 10:25 am

Luke Armstrong wrote:This is the sort of thing that would make me wince: http://www.fxguide.com/wp-content/uploa ... e.0057.jpg


Hehe.. what an half @ssed attempt at greenscreen.. guess they missed the 101 on greenscreen class, Richard should show them how to do it right :twisted:
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Luke Armstrong

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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostWed Sep 19, 2012 10:43 am

Richard Wade wrote:We're been around for what...50,000 years? Human hand movement is possible?

I guess I am asking too much?


That's quite amusing if you take it out of the camera context!

Chroma key is not an ideal technology. The idea of taking all the green out of your image and replacing it with something else is quite nasty really.

Richard Wade wrote:Is that a still from a movie? When is it coming out?


Certainly is... John Carter - was out on March 9 this year.

Here's the final shot: http://www.fxguide.com/wp-content/uploa ... r.0057.jpg

Article about it on FX guide: http://www.fxguide.com/featured/a-world ... hn-carter/
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Luke Armstrong

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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostWed Sep 19, 2012 11:17 am

Ok there are several things wrong with that statement:

1. Increased resolution means better edges - less aliasing, but it doesn't mean a better brightness match between the greenscreen and the target image which is the problem here - which is why you're getting dark motion blur.

2. I've never heard of anybody using 70mm footage to shoot greenscreen for that purpose. Examples?

3. No one ever said you can't do movement with greenscreen - you just can't get great results with a one click key. Any professional will tell you this - and you would know this if you really had the experience you're claiming to have with keying.

4. If you're going to do a proper, scientific test, you need a control - what's your control? If we're talking about Cinema you should be testing it against Alexa or 35mm as they're the standard right now, so what you're saying is someone needs to get a BMC and an Alexa, shoot the same subject with both, and see whether the BMC holds up.

What exactly do you do in the TV/Film industry? Lets see some of your work?
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simonkn

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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostWed Sep 19, 2012 2:01 pm

Richard,

You procrastinated about this in the other thread and it got locked. It wont be long before this happens here.. As someone said, "Isn't this thread about wide angle lenses?"

And quite frankly you are just being rude and obstinate. AGAIN, why are you constantly asking OTHER PEOPLE to do tests for YOU????

You also liken a few people on here to fanboi's... I think as you are on the BlackMagic website you are bound to get people who like their products... And will defend their name.

I really think you should NOT buy this camera. I don't know what field of cinematography you are in (I notice you failed to respond to Luke's request for your material..) But should you actually own one of these cameras and ever have a problem with it... Do you really expect the Customer Service to be that good from BMD? After all the destructive comments you've made on here???

These guys are on Camera No.1 (ok, No.2 technically I suppose with the MFT version..)

Shouldn't we offer enthusiasm and praise at this point and then positive developmental feedback WHEN WE HAVE ACTUALLY USED THE EQUIPMENT?

Professionals (i.e. film-money-making-people) on here see the $3k outlay as a part of their expenditure within their film business. It's a chunk of cash but then what was last years big outlay and what will next years be? So they are happy to wait ...

The students on here KNOW EXACTLY what they are getting - a great deal of 'camera' compared to what they are used to.... So they are happy to wait.

Just which camp are you in?

And please be polite in future.

SK
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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostWed Sep 19, 2012 2:28 pm

Thank you Simon for the note on civility.

This is an open forum, and people can freely express their thoughts. But we do expect the discussion to be civil.

Also, for this thread. I'd suggest starting a different thread around green screen questions since this thread has started to move away from the original topic a bit.

Terry
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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostWed Sep 19, 2012 5:50 pm

In the spirit of open discussion Richard,

Why do you want this camera?

Simon
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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostWed Sep 19, 2012 8:21 pm

No Richard...

Not what the camera is good for.
Not what the camera is bad at.

Why are YOU putting YOUR money on the table? All you've told me is it's no good for telling stories and might be good for a compositor. I'm still no nearer to finding out why you're here, on this forum, peering through the gates into the uncharted territory of black magic cameras. You see, you strike me as a pragmatist who would never jump at a version 1.0 of anything. Wait until its tested, tested and then tested some more. So why are you rushing this camera?
Accusing you of being anti-BM is a little harsh, but then are you truly aware of the magnitude and ferocity of the harsh words you meat out to the BM tech design team and anyone who is excited about this camera, on virtually every one of your posts on this forum. I've had a read back through your posts and you have to go some way back before you've been positive about anything on here... Is that pro-BM behaviour?

As for me...

I shoot weddings and corporates, at present with a lowly Sony Z5. Did me fine for a year. But then I attached an Atomos Ninja. And now the footage is even better. So for me the BMCC sensor size is an enormous increase from 3 little 1/3inch ones. As I said on a previous post, I shoot for the small screen so silly-wide shots don't look good. CUs and MSs are where my stock-in-trade money comes from. And I have a few EF pieces of glass hanging around from my old Canon 1Dmk2 days..
But I want to branch into shorts/music vids. Controlled lighting and the such. So the BMCC is a lovely step up. I had budgeted next period 2013-14 for an F3 or Scarlet, but why? My clients wont notice the difference. But I will, on my bottom line.

No brainer really...

Anyway - i'm happy to toss this spiteful little ball back and forth as it takes our minds off the shipping dates and sensor size... But if the moderators would prefer, we can take it inside - so to speak..?(PM) Otherwise, touché sir - I parry your thrust!
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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostWed Sep 19, 2012 10:16 pm

Hi Richard

I don't want to kick off the debate over the finer details of greenscreen keying, but what was wrong with the test you saw where the girl waves her hand? That was what you wanted to see wasn't it?

Just to keep us on topic, its possible to have wide lenses, they're just not as wide :D
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Theodore Prentice

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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostThu Sep 20, 2012 1:04 am

Luke Armstrong wrote:What exactly do you do in the TV/Film industry? Lets see some of your work?


<crickets>
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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostThu Sep 20, 2012 5:33 am

Richard Wade wrote:... The camera at best can get one a medium shot. Usage of standard wide angle lenses will result in a rude awakening for the uninformed. The only 'solution' is to start buying glass (fish eye) which no one ever would have even considered buying until this camera came along. ...


Hi Richard: You seem to be confused about the difference between a rectilinear lens and a fisheye lens. Either that, or you are purposefully trying to confuse others.

A rectilinear lens represents straight horizontal & vertical lines as straight lines, unlike a fisheye lens which by design exhibits extreme barrel distortion.

For example, the Tokina 11-16mm f2.8 zoom is a rectilinear lens, not a fisheye lens. Also, the Sigma 8-16mm f4.5-5.6 zoom is a rectilinear lens, not a fisheye lens.

Mounted on a BMCC, these lenses yield wide angle field of view results consistent with "wide" and "extreme wide" framing as used in the majority of feature films, television series, TV commercials, corporate videos, and other professionally-produced film and video productions.

The super-extreme wide angle FOV enabled by full-frame video-capable DSLR cameras is the exception, not the rule, and a relatively recent phenomenon in video production (e.g.: since the 5DM2).

Although super-extreme WA is sometimes useful, it's essentially a special effect rather than a core element of motion film/video vocabulary, and like most SFX is perhaps best used sparingly, if at all.
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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostThu Sep 20, 2012 8:16 am

Richard Wade wrote:I just get tired asking the exact same question ad nauseum, only to get ridiculous answers. Fact is: No one
has done a legitimate green screen test.
I'm not asking for the world. For the amount of excuses
posted over the first 'botched' attempt at the greenscreen...Brawley could have easily posted a proper
green screen test. The fact that he only posted a static green screen shot...gives light as to his character.
He knew there was a mild furor over the botched green screen/movement video...so he shoots his
own, probably did have the guy in that video 'waving', but chose to not include it.

Can't trust that. He's only showing us what we want to SEE, not what's really there.



Pull your head in mate.

There's no conspiracy here and I take exception to your tone that I somehow conspired to not show any movement. You're fabricating a story that fits your views I suspect.

I am 3 days from commencing photography on a TV drama series. I am under strict rules about what I can show (from the series, not BMD) and was LUCKY to con the third AD to stand in for me while I was doing tests for the show. I had a few seconds to do so and i APOLOGISE for it not being everything YOU wanted in a greenscreen test

So how about you slow down on the rubbish you're sprouting.

I will post some more shots when I get a chance to. I'll even give you some movement. Maybe some smoke.

I don't have to do any tests. I don't have to make them available for download. You can perhaps show a teeny more respect for those that go to the trouble to shoot tests and make them available.

I'd love to see some of your own tests. Have you been generous enough to do that for the wider filmaking community ? I wonder if someone that has would be so *demanding* of those that are donating their knowledge to the general public.

You don't have to trust me. There will be footage a'plenty to work with before long I'm sure.

There's so many things that can go "wrong" with a greenscreen shot. The camera in this situation, is the least of the issues.

Why be rude and ungrateful. And then make up a story ?

Show me you're a better person than that.

jb
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simonkn

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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostThu Sep 20, 2012 9:17 am

"
John Brawley wrote:
I had a few seconds to do so and i APOLOGISE for it not being everything YOU wanted in a greenscreen test


Apology accepted.

John Brawley wrote:
I will post some more shots when I get a chance to. I'll even give you some movement. Maybe some smoke.


That would be nice."



Ok, if you're gonna get banned/warned you may as well do it for a proper reason..

Richard you patronising, spiteful little worm!
How dare you spout off to someone you haven't even met. And the person you have the audacity to then "thank" for posting the first footage from this new camera.

I think we've all worked out by your "youth-speak" comments, flagrant disregard for cordiality and general behaviour on this forum, exactly who you are and how old you are.
If the damage isn't done already - John, i'd like to apologise on Richard's behalf. Please do NOT think he speaks for the whole BMCC community!

Richard - go back to your bedroom, get your mum to buy you the camera and test it yourself. I don't think anyone on here is prepared to jump through your precise hoops to perfect the test for you. Once you've graduated - get a job and do tests for people so people like you can be content.

To everyone else.... I hope I've verbalised (or is that visualised?) what you've been thinking. If i'm allowed to stay - i'll look forward to the EF mount camera and enjoy the postings..

Good Night..

ps - as you replied to Peter as I was typing..

"My point was: Only because of the BMCC, people are now buying/shopping for fish-eye lenses (8mm)
solely to get some form of wide angle.

- again... rubbish

Oneriver did a good blog post covering the differences between a fish eye vs wide angles:
http://www.onerivermedia.com/blog/?tag=bmcc

The majority of small scale productions are done on location, I guarantee you: A lot of camera operators
will begin to 'loathe' the BMCC due to the fact that they will basically have to stand in hallways/outside
just to get a decent wide shot. "

- I saw the video, and remember the bit about standing in the hallway / outside. Nice lift.

SK
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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostThu Sep 20, 2012 9:28 am

Oh and to save time... I've pressed the "Report This Post" icon myself...
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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostThu Sep 20, 2012 9:34 am

Canon 8 - 15mm is what I've been using and I love it!

Cheers,

Rick
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Luke Armstrong

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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostThu Sep 20, 2012 9:37 am

Richard Wade wrote:Luke Armstrong wrote:

Just to keep us on topic, its possible to have wide lenses, they're just not as wide


Richard Wade wrote:That's being disingenuous.


That's not disingenuous, it was a flippant comment to point us back to the original topic, but it was inherently correct: the mismatch between the sensor size and lens will cause the apparent field of view to be reduced.

Richard Wade wrote:Right...so a guy waving his hand...is verboten.


Bit weird asking the 3rd AC to wave his hand at the camera... Those sort of comments should be verboten. Don't be so ungrateful. As a compositor I found those tests very useful, I was able to get a great key out of that footage. I don't CARE about the motion blur because its irrelevant. Seriously... it has nothing to do with the camera. Go read the comments under the original Vimeo posting.

What exactly do you do in the TV/Film industry? Show us some examples of your work?

Richard Wade wrote:John Brawley wrote:
I had a few seconds to do so and i APOLOGISE for it not being everything YOU wanted in a greenscreen test


Apology accepted.


Richard, it would be good if you apologised to John, he doesn't work for BMD and isn't obliged to do anything for us. He makes his living as a Cinematographer, not a public relations officer or a camera tester. He is speaking from his experiences and we're lucky to have his input.

Please think about others' feelings.
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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostThu Sep 20, 2012 10:14 am

Richard Wade wrote:Hi Folks,

I think you all need to chill out. This is just a camera we're talking about here.




I think you need to adopt a more collegiate tone, stop insulting those who seek to have a genuine discussion with you, and perhaps not invent stories.

Maybe consider why it is you already have a warning notice when no one else here does.

You conciliatory tone is hollow when you still seem to stand by your previous incorrect assertions.

You have a singular point of view. Plenty of people, who have identified themselves as professional compositors have suggested a very different opinion to yours here and elsewhere yet you continue to use hysterical language to describe a "fault" few professional compositors have any trouble with.

The very fact you demand 264 comparison footage says you don't speak with the knowledge of experince.

JB.
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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostThu Sep 20, 2012 3:49 pm

This doesn't seem to "civil" to me...the name calling and whatnot. :shock:
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Kristian Lam

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Re: Crop factor 2.4 : how is possible have wide lenses ?

PostThu Sep 20, 2012 4:08 pm

Alright guys, that's enough.

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