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  • Hey all, just changed over the backend after 15 years I figured time to give it a bit of an update, its probably gonna be a bit weird for most of you and i am sure there is a few bugs to work out but it should kinda work the same as before... hopefully :)

Black sun

Shawn Nelson said:
I was filming a laser cutting thick stainless steal blades and this flare filled the whole screen for about a second that was unlike any flare I've ever seen.
Click to expand...

I saw a clip from a camera that got it's CCDs burnt by reflections from a laser during a medical treatment, as it happened. Saw this happen on an XDCAM...the laser was NOT pointed into the lens as you might expect...the light that burned the block was the diffused laser light reflecting back everywhere...and it left permanent trails on the CCD. The tech operating the laser had eye protection on, but the camera of course did not.

Be really careful. I think you probably dodged a bullet there.
 
As for pink/black bits...

My F350 XDCAM exhibits pink bits when light sources are in the frame, and the hot spot goes over a certain level. They are easy to fix in the color correct, because the level of these pink bits is always over 100 IRE. Desaturate completely everything over 100IRE (which is never a bad idea anyway to make broadcast safe) and it's fixed.

Now black spots...that would be horrible to fix, and like everybody has already said, garbage mattes and tracking I think would be the only way to fix. That's not worth it.
 
NateWeaver said:
I saw a clip from a camera that got it's CCDs burnt by reflections from a laser during a medical treatment, as it happened. Saw this happen on an XDCAM...the laser was NOT pointed into the lens as you might expect...the light that burned the block was the diffused laser light reflecting back everywhere...and it left permanent trails on the CCD. The tech operating the laser had eye protection on, but the camera of course did not.

Be really careful. I think you probably dodged a bullet there.
Click to expand...

Yeah, I was definitely not in the path of the laser, I was filming it cutting. That should never present a problem to a well designed CMOS camera. This was at the beginning of a full day of shooting and the camera is fine.
 
Brook Willard said:
I just achieved it on a new ["X"] body with build 12 yesterday.

It is still there. But I'm glad to hear that the team is working at it.
Click to expand...

Brook can you post this so we can understand it better....You know ................a picture is worth a thousand words !
 
With our camera 88 and build 12 we still have the black dot in the sun. If you look at the footage in RedCine or Scratch using the REC701 metadata it's covered by the white clipping around it, but as soon as you check the raw footage you see it clearly.
Arno
www.locared.com
 
Shawn Nelson said:
Yeah, I was definitely not in the path of the laser, I was filming it cutting. That should never present a problem to a well designed CMOS camera.
Click to expand...

I think it has to do with the power of the laser, and the unlucky reflection angle the camera had.

If a laser device has a huge warning label on it, like other industrial cutting/medical lasers I've seen have, and says to wear special eye protection, I dunno if it's safe to assume your camera is safe. I wouldn't bet my $5000 CCD block on it, would you?

I'm not trying to bust your balls, I'm just saying I think if you had seen the clip I had seen, you probably wouldn't have done it. I never would have guessed it could happen before I saw the clip either.
 
Here:

A001_C022_901226_0000.jpg



I don´t have frames of the sun itself, because i just simply didn´t wanted footage with a black hole in the sky.Those really bright windows should be white.
Camera one hundred seventy something, build 12.
 
That's definitely sensor protect. Too flat and constant to be something optical. And looks like it would be even more annoying to remove than it hard clipping to pure black (which could be luma-keyed to white with a rough garbage mask.)

I was actually just going to recommend the same thing as flameop. An RLE compressed alpha channel. Even if you have a lot of clipping you're going to be looking at, worst case scenario, a lossless 20KB file. Then REDAlert and REDCine could isolate and remove it during the debayer and could be tweakable by the user.

The problem is the more natural it gets the better it looks but the progressively more difficult it becomes to enhance if post if it's not perfect. The extreme being a pure magenta being perfect for removing in post but completely unnatural and a neutral 254,254,254 looking dramatically better but being useless for correcting.

Edit: For example the supplied image's alpha could be compressed to 2KB.
 
Akube said:
interesting...

What i'd recc. is... leave the option as on/off both in post and on camera... but the camera should by default have it ON. and add purple for the almost over exposed areas.
when you take the footage in post... like on redcine... you can tell it to shut it off. and then... its upto you.. if you want to fix up the black stuff... then export to .dpx for ae or shake.

if you dont want to... well.. the black stuff isnt really there.. its just this option that is availble in your software or on your red lcd monitor that you can activate or de-activate. it is only burnt black on the footage when you litterally tell it to in redcine or fcp... *since fcp can read r3d files :D :D* hint hint. lol... heahaha.
Click to expand...

I think this is the right idea. Give the user as many options during both shooting and post as possible. Perhaps a special Zebra-type pattern could be toggled for the LCD/EVF to help monitor this.

NateWeaver said:
As for pink/black bits...

My F350 XDCAM exhibits pink bits when light sources are in the frame, and the hot spot goes over a certain level. They are easy to fix in the color correct, because the level of these pink bits is always over 100 IRE. Desaturate completely everything over 100IRE (which is never a bad idea anyway to make broadcast safe) and it's fixed...
Click to expand...

This is a good point. While working on solutions, it wouldn't hurt to take a look at how other Cameras are handling this issue. It's possible that we don't need to re-invent the wheel on this if there is a very sound way to deal with it already.

But by all means, inventing something better is also not a bad thing. :)
 
Ok the posted photo does explain the area of concern.

I believe any camera shooting a severely over exposed subject will have the same effect.. My Pentax CCD D10 would show the same effect if I shot that building.

Did you have the Zebra on? The fix would be to close the F stop by 1 or 2 stops
before exposure…
 
David Birdy said:
Did you have the Zebra on? The fix would be to close the F stop by 1 or 2 stops
before exposure…
Click to expand...

If you want 2 more stops of noise.

That's not a solution.
 
So what about when you're on a stage, and you paper the windows and blow them out? Do you have to be at exactly 103 ire so they are blown out but not black? What about back-lit smoke that should be burning out? I'd love to see some extreme exposure situations.

Did a shot one time where the only source in the room is a 6k hmi shooting in a 2x3' window, atmospheric smoke, big god ray, hitting a small round table that has a white cloth on it. The bounce from the cloth lit the five people that walked into the room and gathered around it. I of course exposed for the faces and shot around a 2.8-4 split. The window was over 100 ire, parts of the beam were over 100 ire and of course the table was over 100 ire. How would the red handle a situation like that?


Cheers,

Nick Gardner
 
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