Pocket 4k Dead Pixel

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Blaine Suque

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Pocket 4k Dead Pixel

PostThu Oct 18, 2018 5:53 am

Hey guys,


I got my Pocket 4k about a week ago. Since then i have shot a couple test around home and also used it on a wedding. I noticed I have a dead pixel at higher ISO's ....but when i did an ISO test I actually noticed its visible around 200. Here are some frames of what i am talking about. I already talked to BM and i have to send the camera back to get check out or replaced, hopefully i do not have to wait again. Link below :

https://www.dropbox.com/sh/o1l3drnu6b6i05g/AAA-jYqofKxm3Z9xa--32ftaa?dl=0

https://www.dropbox.com/s/dleif6qua8r35mm/A004_10071334_C067.mov?dl=0


Since the battery life sucks with Canon LP's i went and bought the Core powerbase, and it will last me almost 4 hours. 2 of these and im good for most run n gun shoots. Link below.

[url]
https://www.adorama.com/sxpbebmpc4.html ... gIJfvD_BwE[/url]

Other than that issue the camera is awesome, cant wait for a firmware update and possibly BMRAW.
One thing i wish to see soon be an option is to be able to disable the touch screen. I use this camera just like a dlsr with a strap and throw it over my shoulder for the day. When its on, the touch screen will constantly hit your body or clothes and push buttons.


I will upload a real test soon and post. just havent shot anything fun yet with it. Maybe some surfing really soon.
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Bearallison

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Re: Pocket 4k Dead Pixel

PostTue Oct 23, 2018 5:59 pm

I have noticed at least three hot pixels on my Pocket 4k.
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Blaine Suque

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Re: Pocket 4k Dead Pixel

PostWed Oct 24, 2018 5:10 am

Bearallison wrote:I have noticed at least three hot pixels on my Pocket 4k.

At lower ISO's?

What are you going to do about it? Send it in or keep it?
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Bearallison

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Re: Pocket 4k Dead Pixel

PostWed Oct 24, 2018 1:07 pm

At all ISOs. I haven't decided yet, I have been using it and have created a power grade inside of resolve using the dead pixel plug-in. I just apply that to the footage before grading and it looks fine.
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rick.lang

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Re: Pocket 4k Dead Pixel

PostWed Oct 24, 2018 6:35 pm

I recently had a single stuck pixel and have done that same. I think BMD has a policy related to dead pixel exchanges and as far as we’ve heard in the past, they won’t replace a camera with one dead pixel. If it was delivered to you like that, they may or you can return it to tour vendor. My dead pixel only showed up after I had the camera more than a couple of years. In my recent wedding the stuck pixel wasn’t on my daylight footage but persisted in low light.


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marcellomazzilli

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Re: Pocket 4k Dead Pixel

PostSat Nov 03, 2018 9:11 am

Bearallison wrote:At all ISOs. I haven't decided yet, I have been using it and have created a power grade inside of resolve using the dead pixel plug-in. I just apply that to the footage before grading and it looks fine.


Can you explain more? I have little or no experience with Da Vinci. Can you tell us one by one the operations to create this correction for Dead Pixels? Thanks
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marcellomazzilli

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Re: Pocket 4k Dead Pixel

PostSat Nov 03, 2018 9:15 am

I hope this will be resolved soon by Firmware updates. I don't remember having similar problems on ly BMPC4K and believe it was addressed automatically. I never saw a function to "reset dead pixels". Some cameras (other brands) have a specific procedure to do if you notice them. How does it work on Ursa, URSA Mini and Ursa Mini Pro ?
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roger.magnusson

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Re: Pocket 4k Dead Pixel

PostSat Nov 03, 2018 12:57 pm

In a facebook thread about stuck pixels on BMPCC4K Kristian Lam from BMD said that the local support offices can remap those pixels.
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rick.lang

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Re: Pocket 4k Dead Pixel

PostSat Nov 03, 2018 4:01 pm

Marcelo, I add a serial node in the Resolve Colour Page reserved just for my one dead pixel that appeared a couple of months ago. After you add the node, in the upper right part of your screen, click the OFX and scroll down the list to the Repair or Restore effects (recently renamed I think so not sure) and there you select Dead Pixel. Drag that effect to the new node you added. You’ll then need to tell Resolve which pixel to modify by dragging a tool to it.

The size of the tool used to locate and modify the dead pixel is 2. That’s too small to locate the pixel, so you can make it larger temporarily such as 10. When you’ve got it centred, then set the size back to 2. You’ll see the dead pixel take on the average colour of its neighbors.

If you have several dead pixels, just use the tool to identify each location.

The dead pixel will likely be in every clip, so then you need to copy the node to the other clips.

This is tedious, so it someone can detail a more efficient process, please do.

Since the dead pixel is in the same place in every clip, it’s unfortunate that Resolve doesn’t fix it everywhere instead of one clip at a time.

Heck, put it in the project presets as the physical location on the sensor and have it apply automatically in every project regardless of resolution.

Or even better. Define the dead pixel in the camera, d’oh!


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John Paines

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Re: Pocket 4k Dead Pixel

PostSat Nov 03, 2018 4:09 pm

Why not apply the dead pixel node, from a powergrade, to the entire timeline, rather than one clip at a time (you'll need to switch from "clip" to "timeline" on the Color page for this one operation)?
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rick.lang

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Re: Pocket 4k Dead Pixel

PostSat Nov 03, 2018 10:18 pm

Thank you, John!


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tillkrueger

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Re: Pocket 4k Dead Pixel

PostTue Nov 13, 2018 6:06 am

oh brother, I just found this thread out of necessity...I just rendered out my first 1250 ISO RAW clip from my new PCC4K, which left me flabbergasted with its beautiful colour even in low light, when lo and behold, a white stuck pixel reared its ugly head...why oh why?!

ok, time to figure out my options...plugin, Fusion, local BM office support...what's the best way to deal with this...I'd love to have it taken care of on the hardware level, or at least in firmware, but I'm probably not alone with that. Since I purchased the camera on eBay from one of the lucky guys that got their pre-order way before I would have gotten mine, I am unable to go back to the "vendor" (no returns, not that I would want to *return* it!), so does anyone know what the local BM office might be able to do?

btw, hi Rick! you're in every discussion, aren't you?
maybe I will be omnipresent like you too, some day. ;)
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rick.lang

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Re: Pocket 4k Dead Pixel

PostTue Nov 13, 2018 6:11 am

Omnipresent but never omniscient!


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tillkrueger

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Re: Pocket 4k Dead Pixel

PostTue Nov 13, 2018 6:15 am

dang! I hoped you would be...

too tired now, but tomorrow I'll have to dig deeper, find out whether it's just one stuck pixel, then maybe call BM to see what their stance is. Maybe my SquareTrade warranty would cover it if BM doesn't. But if it's just one pixel, I may learn to live with it, if all else fails. Still, I'd love to find a way to get it "unstuck", or dealt with in the firmware, maybe.

oh well, time to see the sandman...g'nite all!
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Danny Wincott

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Re: Pocket 4k Dead Pixel

PostSun Nov 18, 2018 6:57 pm

roger.magnusson wrote:In a facebook thread about stuck pixels on BMPCC4K Kristian Lam from BMD said that the local support offices can remap those pixels.


Link to the thread?
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Danny Wincott

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Re: Pocket 4k Dead Pixel

PostSun Nov 18, 2018 6:59 pm

I have a dead pixel too and a friend in the same town has one also :(
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tillkrueger

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Re: Pocket 4k Dead Pixel

PostMon Nov 19, 2018 6:08 pm

there's probably a good reason why BM has added a feature in Resolve to deal with such pixels ;)

still would love to not have to deal with it in post.
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Re: Pocket 4k Dead Pixel

PostMon Dec 24, 2018 4:16 pm

I got my third Camera today with the third dead pixel. I would just send it back and ask for my money but i already own a cage and other accesories for it. I´m starting to think that people without dead pixels just didn´t look for it :lol:
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roger.magnusson

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Re: Pocket 4k Dead Pixel

PostWed Dec 26, 2018 10:43 pm

Just contact BMD and they will map out the stuck/dead pixel. They did with mine and it's perfect now.
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Wayne Steven

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Re: Pocket 4k Dead Pixel

PostThu Dec 27, 2018 3:45 am

Filling in a dead pixel is not a fix, it's a cover up. What people have to ask, is if it has dead pixels out of the box, how bad will it get over the life of the camera. But for local small work, like school fates, community groups etc, it won't matter. The more to the sides and bottom and lower the resolution, the better after fill in for all work.
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Ryan Payne

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Re: Pocket 4k Dead Pixel

PostThu Dec 27, 2018 4:09 am

I believe most cameras will automatically remap dead or hot pixels so you'd never know they were ever there.
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rick.lang

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Pocket 4k Dead Pixel

PostThu Dec 27, 2018 4:46 am

My previous few client shoots with the Mini 4.6K had a single ‘dead’ or ‘stuck’ pixel that wouldn’t go away even with recalibration. My first clip is always a test against a dark colored background so I can easily find that single fault and correct it in Resolve. However my last shoot, it was gone.


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Wayne Steven

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Re: Pocket 4k Dead Pixel

PostThu Dec 27, 2018 7:40 am

It is not likely an accurate map, so if it is in central vision you may notice it. But once you down scale, the delivery pixel includes more and more sensor pixels surrounding the dead pixel, which hides it more and more. So, 2K and SD guys should be happy more often. :). You just weigh up if it really matters for your work. A lot of people it might not matter, they can live with one dead pixel, and eventually dozens and dozens.
Often people deceive themselves so much they do not understand, even when the truth is explained to them.
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Re: Pocket 4k Dead Pixel

PostThu Dec 27, 2018 10:31 am

roger.magnusson wrote:Just contact BMD and they will map out the stuck/dead pixel. They did with mine and it's perfect now.


i did this 2 times before :D
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Re: Pocket 4k Dead Pixel

PostThu Dec 27, 2018 12:13 pm

Wayne Steven wrote:Filling in a dead pixel is not a fix, it's a cover up.

All cameras have dead/stuck pixels that are remapped by software. For BMPCC4K it's just not user configurable. At least not with the current firmware.
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Wayne Steven

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Re: Pocket 4k Dead Pixel

PostThu Dec 27, 2018 1:23 pm

Yep. But it's still not an actual hardware fix.
Often people deceive themselves so much they do not understand, even when the truth is explained to them.
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Ash A.

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Re: Pocket 4k Dead Pixel

PostFri Jan 04, 2019 1:01 am

I just noticed a dead pixel today after having the camera for two months. I was looking for Blackmagic contact info when I decided to do a factory reset on the camera. The pixel seems to be back to normal because I can't find it again. Has anyone else ever fixed a pixel with a reset? I'm running firmware 5.2 BTW.
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Re: Pocket 4k Dead Pixel

PostWed Jan 09, 2019 7:48 am

Same here, Just received my baby today and noticed a little red dot , i cranked ISO an I noticed 2 more...i read the above, hit reset an bam they seem to be gone...but i now notice one on the very bottom right corner...i shoot mainly 2:35 & this wont effect me but knowing its there its bothering and would like to get fixed if its a same day or next dat turnaround here in NYC
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Re: Pocket 4k Dead Pixel

PostWed Jan 09, 2019 1:35 pm

Dead pixels have been the bane of my life recently on all my bm cameras. Exposure to cosmic rays is minimal, but they will knock out pixels at a rate of about 1- 3 a year. If you fly, particularly transatlantic, the exposure is about a years worth in one flight. There's nothing that can be done to shield them other than several metres of concrete and all cameras are affected, though most will detect and mask them. On a recent flight from LA to the UK, I developed 7 dead pixels on the UMP and two on the broadcast. BM will remap them for you, both cameras are there now, but it would really help if this could be integrated into the next firmware, to check on boot up. You'll notice them at higher iso and once the camera warms up - with peaking on max, you'll see them at most iso, they're really annoying and distracting!!
In the olden days of digibeta, multiple black balances would get rid of them. Coming from a Sony f5 and c300, I never saw them on those cameras so presumably they were doing some internal remap then. I travel a lot and its not practical, generous tho BMD have been, to keep sending them back for a remap.
You can map them in post but I work solely in broadcast where I hand the rushes over at the end of the day. My competition on productions is with other DPs owning arri, Sony or canon and even though I've owned those and prefer my ump, it's always a slight battle until production sees the rushes to get BM cameras onto the jobs in the first place, which is why I can't afford to be seeing 7 dead pixels after one flight.
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Wayne Steven

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Re: Pocket 4k Dead Pixel

PostWed Jan 09, 2019 2:54 pm

Patrick, not even with diamagnetic materials shielding the parts (like thick Aluminium)?

I'm curios, do Alexa, Don't, Red get similar rates of dead pixels during these flights. I'm curios if they design sensors better to cope with them. Gold is a higher diamagnetic, and I don't know of its visual aberration properties, but pure gold is said to be clear, and they use it making some bluray discs for that purpose. Which means you might apply it to sensor glass and around a sensor at manufacture. There are some other exotic materials more exotic.

But what about a Faraday cage? A cage around the sensor night be an option a manufacturer would have to get approved for travel (for the risk of fire. Ultra capacitor?).
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Re: Pocket 4k Dead Pixel

PostWed Jan 09, 2019 3:27 pm

Wayne Steven wrote:But what about a Faraday cage?


That would be an interesting thing to test. You can make a very cheap and effective faraday pouch with aluminum foil (2-3 layers thick). For a camera the size of the Pocket 4k it would be very manageable. Worst case, it does nothing and you have extra aluminum foil to wrap up leftover food. Best case, you have fewer dead pixels after your flight.
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Re: Pocket 4k Dead Pixel

PostWed Jan 09, 2019 3:33 pm

Wayne Steven wrote:I'm curios, do Alexa, Don't, Red get similar rates of dead pixels during these flights.


I bet those cameras (especially Alexa) don't normally fly, they are rented on location.
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Wayne Steven

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Re: Pocket 4k Dead Pixel

PostWed Jan 09, 2019 5:41 pm

Spencer_Meyer wrote:
Wayne Steven wrote:But what about a Faraday cage?


That would be an interesting thing to test. You can make a very cheap and effective faraday pouch with aluminum foil (2-3 layers thick). For a camera the size of the Pocket 4k it would be very manageable. Worst case, it does nothing and you have extra aluminum foil to wrap up leftover food. Best case, you have fewer dead pixels after your flight.


I was thinking more thick aluminum case/box.

You need something that can deal with the specific energy of the charged particle enough to stop or deflect the particle around the sensor.
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Patrick Acum

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Re: Pocket 4k Dead Pixel

PostFri Jan 11, 2019 10:49 am

Neutrino detecting is often placed miles under ground, in old mine shafts so the results are uncontaminated by other sources. Nothing stops the neutrinos so anything detected at massive depth is a cosmic particle. If you're going to use foil, you may as well make a hat too, to protect you from the government stealing your great ideas!
Im presuming red and arri have software that detects and auto remaps on boot. I never had this issue with sony or canon, and I've always flown a lot, which is why Id like to see something implemented. Its got to be cheaper for BM to do it in firmware than keep shipping cameras back and forth, Tim Schumann??
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Re: Pocket 4k Dead Pixel

PostFri Jan 11, 2019 5:30 pm

So, you have one for that?

You realise neutrinos are not the cosmic particles we are interest end in, and we are more likely to get hit by the secondary particles like protons. However, still, what are the energies of these secondary particles we have to deal with? That tells you more what's needed to handle them. Still, is the depth to protect the apparatus from cosmic ray effects, or other things? I'm not familiar with the research.
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Spencer_Meyer

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Re: Pocket 4k Dead Pixel

PostFri Jan 11, 2019 6:45 pm

Patrick Acum wrote:Neutrino detecting is often placed miles under ground, in old mine shafts so the results are uncontaminated by other sources. Nothing stops the neutrinos so anything detected at massive depth is a cosmic particle. If you're going to use foil, you may as well make a hat too, to protect you from the government stealing your great ideas!
Im presuming red and arri have software that detects and auto remaps on boot. I never had this issue with sony or canon, and I've always flown a lot, which is why Id like to see something implemented. Its got to be cheaper for BM to do it in firmware than keep shipping cameras back and forth, Tim Schumann??


So... let me get this right. Nothing can stop neutrinos, Neutrinos can pass though many lightyears of space and 100's of feet deep into the earth unimpeded, but we're mysteriously bombarded by more of them in the air than on the ground? And that's why it's common to end up with more dead pixels after a flight? Is the atmosphere dense enough to show a significant reduction of them from 30,000ft to sea level?

Neutrinos aren't known for having a great deal of interactivity with matter, so to assume that they are the primary culprit for dead pixels is pretty unfounded (X-rays make for a much better perpetrator). On the other hand, the use of aluminum foil pouches as a DIY faraday cage is a perfectly acceptable way to block electromagnetic radiation. And given that cosmic rays and most of these other scientific phenomenon are essentially electromagnetic radiation of different forms, wavelengths, and intensities, a tiny faraday cage would in fact have some benefit (even against x-rays to some extent).

I recognize that higher energy particles would pass right through foil, many lower energy particles would not. Like I said this is just something to experiment with, it would be extremely low cost and if you notice fewer dead pixels after a flight, then it saves you some time and lost productivity. If it doesn't make a difference, then you're only out a couple of bucks. In either case you'll know whether a heavier duty enclosure would be a worthwhile investment.

Finally, I don't need to worry about the gov't stealing this idea from me, because I stole the foil faraday cage idea from the gov't. Besides, I'm not selling this as gospel truth or forcing anyone to try it, so in the future save the snarky comments about tin foil hats and just scroll scroll on by.

(My foil hat is quite cunning by the way. :D )
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Re: Pocket 4k Dead Pixel

PostSun Jan 13, 2019 11:43 am

You are absolutely right about Neutrinos.
But you can test your idea regarding protection quite easily: put your foil around your camera when you try to have it in carry-on baggage on your next flight. If they ask you to unpack and show it, you are right (to some degree). If not, it has no significant effect. The modern devices in airport scanners have pretty low energy radiation, many particles that hit you in high-flying airplanes have a considerably higher impact. And if I write "particles" you'll probably know about their double character being waves too.
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Re: Pocket 4k Dead Pixel

PostSun Jan 13, 2019 1:39 pm

Man, they packed a bomb in a neat grinder a d they found it. But in reality, a lot more particles will be secondary particles of lower energy. I had something really strange happen to me one day. I was in an open air vehicle and something hit me from nowhere and left a little tiny crater in my skin. It obviously came from the sky and hit with not so much physical force. I thought was thinking surely not. Whatever that was aluminum plate would have helped better than foil.

It's interesting, there are a lot of reports ofdeas pixels, join arrival. I wonder how much is due to people getting their new can era air freighted to them, including stores?

My battery is about to die, so I'll split this post.
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Re: Pocket 4k Dead Pixel

PostSun Jan 13, 2019 2:11 pm

In deep space travel, I read. They have an issue, using metal shielding, the shielding being hit spreads out secondary particles. I can't remember what the solutions were, except a water bladder surrounding the crew section and a strong magnetic field of a plasma reactor.

Now, the Earth's magnetic field actually filters out a lot of stuff. In the first moon missions, they were reporting a lot of mysterious visible flashes, because at that distance the Earth's magnetic field is too weak to stop them. However, I thought cosmic rays are supposed to be rare bat ground level. I would have to look up something like that, but I imagine what people are seeing is a lot of secondary particles of lower energy. A single cosmic ray should spray them out. The direction of most energy should be where the atmosphere is the thinnest, and the travel on an angle should reduce the energy of the particles. So, get a thick aluminum box, place the camera so the sensor is upright during travel, minimizing the surface area exposure to the highest energy particles, and see what happens.

Of course, a simpler explanation might be that because it happens more with international travel, could it be from the security xray scans of your luggage. Something worth finding out about.
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Re: Pocket 4k Dead Pixel

PostMon Jan 14, 2019 10:31 pm

"It's not the X-Ray scanners at the airport that do the damage, it is high energy neutrons from cosmic rays that can lead to bright pixels. It would take something like 200m (600ft) thick concrete or many feet of lead to have any noticeable protective effect. Some of these particles can pass right the way through the earth. So it's not practical to try to shield the sensor. The potential for damage is worst on north polar routes as the earths magnetic field concentrates cosmic rays in the northern polar regions. Transatlantic flights and flights between Europe and Japan use very northerly routes and can be amongst the most likely to incur damage. In this case a single 12 hour flight is the equivalent of around 100 days at sea level in terms of the potential for pixel damage.

Sony now no longer ship cameras or sensors using polar flights. I've experienced hot pixels after transatlantic flights on many occasions, but have always been able to use the cameras masking functions to eliminate them. The same particles can cause problems with memory chips, but in most cases these are not permanent.

The sensor element of a CMOS chip can also be effected by cosmic rays, but they do tend to be a bit more robust and the way a CMOS sensor is read means that any damage may be less apparent."

Alistair Chapman, all things sony guru

"Sensor damage due to cosmic radiation is quite common. I've seen it many times on my own cameras. On the ground you can expect a pixel hit between about once a year and once every 100 days. It's just that the cameras pixel masking, some of which is fully automatic will do it's job and hide the damaged pixels. I chase storms driving 40,000 miles a year and I don't get struck by lightning that frequently or get involved in train or car wrecks."

"Seemingly, there is no protection from it, yet most people are not even aware of the issue. But everyone knows about lightening! (Sorry, couldn't resist).A few minutes with google will turn up plenty of research and evidence on the damage that heavy cosmic particles do to electronic equipment where basically the particle punches a hole through the insulating layer in semiconductors, thus allowing current to leak in or out. This isn't speculation or hearsay. There is no "if", it happens day in day out.
Most professional camera crews are aware of this. Certainly Canon and Sony include a note about white flecks caused by cosmic radiation in their stills and video camera manuals. As I said, and if you do your research you will find that there is nothing practical that you can do to protect your equipment from these particles. It's been speculated that if you surround electronic equipment with a large amount of liquid Hydrogen you can reduce the damage, but that's just not practical or sensible.

There's nothing you can do about it, so you have few choices:
1) Don't buy a video or electronic stills camera with a CCD.
2) Minimise exposure by never placing equipment on an aircraft, if you must, avoid polar routes.
3) Don't stress about it, get on with your work/life and just accept that one day you might get a hit that can't be masked in camera.

There are software plugins that can mask hot pixels in post as a last resort.
Removing the battery, a metal case, antistatic bag etc make no difference whatsoever."
http://www.dvinfo.net/forum/archive/ind ... 89119.html
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Patrick Acum

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Re: Pocket 4k Dead Pixel

PostMon Jan 14, 2019 10:43 pm

https://www.google.com/url?sa=t&rct=j&q ... iCJIJUkMp4.
"CONCLUSION
The effect of terrestrial cosmic radiation in the generation of hard errors resulting in hot pixels for solid sate image sensors has been studied. Hot pixel developments at sea level (terrestrial cosmic radiation environment) are corroborated successfully with accelerated neutron beam tests for the first time. Influence of neutron flux (dose rate) and biasing on hot pixel development is also reported. These experiments provide further validation to the hypothesis that the prominent cause of hot pixels is displacement damage in the silicon bulk due to neutron radiation, introduced by secondary cosmic rays."
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Re: Pocket 4k Dead Pixel

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Wayne Steven

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Re: Pocket 4k Dead Pixel

PostTue Jan 15, 2019 12:20 am

Thanks Patrick, this is what I was talking about. 20 meter concrete will absorb them, not hundreds needed.

The term secondary comic rays, confuses the issue, as they are really lower energy particles from impact showers from cosmic rays as indicated before. So, the main culprit is these showers, and it is best to lower the energy if those before they reach the sensor. Now, I mention a few methods worth trying they use in space for primary rays, water and magnetic field. So, can an aluminium case (as a cheap diamagnetic material) and a secondary thick gel pack be enough to reduce the energy potential.

Now, saying hundreds of meters or tens of meters of earthen like materials is needed. These materials are largely magnetically neutral offering less resistance to the showers and primaries, however a diamagnetic material isn't and actively enforcing resistance to charge particles I would imagine. Being a solid metal, it offers some additional resistance which vsn produce lower energy showers of its own. So, thickness should matter. Now, gels packs can be largely water, which emulates the deep space protection proposal, and catches some of the showers. So, while a primary might get through mauve must if the showers will be constrained in energy. So, even if a 90 or 99% improvement would be great. Of course, you have the camera in a secondary inner container in case the gel leaks.

Now, are you sure that airport security scabs aren't responsible for st least some of this. They detected the meat grinder with bomb in it with a scan I think. So, they might be using significant energy. The reports discussed so far were on international flights, where you have extra security in the past (now I don't know how much domestic flights have in recent years). Long domestic flights should be high altitude too. But were there less pixel problems on them then long international flights, in the past? So many things to answer in research.

Now, did you look up the techniques they use to produce radiation hardened sensors and chips? To see if those techniques could he applied here?

Thanks.
Often people deceive themselves so much they do not understand, even when the truth is explained to them.
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Re: Pocket 4k Dead Pixel

PostTue Jan 15, 2019 12:34 am

So, reflecting in this stuff as reading, I live in a good area for this and my cameras travel by land, so that may be behind my lower incidence.

I wonder though, does traveling with the kens on affect any of this. The lens have concentrating surfaces. Though tuned to visible light, they should also have effect on these things hitting them on an angle, or straight on.
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Re: Pocket 4k Dead Pixel

PostTue Jan 15, 2019 2:23 am

OK. Reading through that dvinfo link, there seems to be a number of things mistaken there. But, there was even a good link there, to a thread that put bunkum to their assumptions.

The thread pretty much refers to real world protections use in space for much stronger primary particles. You could expect these to work much better in the atmosphere in secondary particle showers. Its pretty much along the lines of what I said, except the sheets of magnets. Magnets are known to stuff around with sensors. You could luyetslky try what I said, adding different levels of protection to the case, until it worked really well, and you are probably going bewilder airport security with a case like that. I imagine they will want to test a gel pack at some time. However, the pocket only requires a small case which can go in foam in a normal case.

https://www.cinematography.net/edited-p ... lStuck.htm

Very little you can do for a cosmic ray other than carefully placed magnets around your CCD. In fact this might be your best bet. It only takes a very small magnetic field to deflect these particles. More than 80 of cosmic rays are hydrogen nuclei and most of the others are helium nuclei.

They come not as much from our sun but from supernova explosions and the like way out there in places we can't see. Some are real bad boys as the heavy ones are massive atomic nuclei such as nickel and zinc. Yes they pass easily through you and the earth but most are deflected/and or dissipated when they enter the area around the earth hitting other particles. In fact, one of the reasons why we do not know where they come from is that the interstellar magnetic field prevents cosmic rays from reaching the earth directly so their paths here can't be plotted. In astronomy we actually use CCDs to measure cosmic ray particle counts.

If you took a piece of fabric and mounted magnets to it all in the same direction of pole and placed them on either side of your camera, you might be better off than flying in an airplane alone. No guarantee, but definitely has an effect on these particles. The higher you go and the more you go in airplanes the better the odds you are going to start to loose pixels.

Perhaps if enough folks are interested, I'll manufacturer one.

Walter Graff
Producer, Director, Creative Director, Cinematographer
AdZone, LLC
BlueSky Sports and Entertainment Marketing, LLC
HellGate Pictures, Inc.
http://www.film-and-video.com

I just talked to a couple of knowledgeable guys around here and we don't have a sure fire solution yet for our HD cams that are on orbit. We currently see a fairly short life expectancy.

Currently our best protection is to store the cameras between water bags on the station. This seems to help a bit. We store film between the station's batteries, but there is not enough room to get a camera body in there. Also, I have it on good authority that Liquid Hydrogen is an effective blocker. But none of this helps your situation with regards to flying in aircraft.

I offer it just for general knowledge.

Michael Bravin
class="style9">>We currently see a fairly short life expectancy.

Hence why Hubble optics were already replaced.

class="style9">>Currently our best protection is to store the cameras between water >bags on the station.

Hydrogen molecules in water and since most cosmic rays are hydrogen protons...

class="style9">>Also, I have it on good authority that Liquid Hydrogen is an effective >blocker.

More hydrogen molecules tightly packed together. Works even better to stop molecules. But not all the molecules, especially the heavy metals I'd imagine.

class="style9">>But none of this helps your situation with regards to flying in aircraft. I >offer it just for general knowledge.

As in not a cosmic ray of light?

Walter Graff
Producer, Director, Creative Director, Cinematographer

Walter Graff writes :

class="style9">>If you took a piece of fabric and mounted magnets to it all in the same >direction of pole and placed them on either side of your camera, you >might be better off than flying in an airplane alone.

Fabric sheets with embedded magnets are already available from some medical supply sources, for use in magnetic therapy (mainly for joint healing). Whether those magnets are strong enough to divert high-energy particles is a separate question. (Or will they just as often divert particles right into your CCDs?)

Dan Drasin
Producer/DP
Marin County, CA
Often people deceive themselves so much they do not understand, even when the truth is explained to them.

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