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  1. #1 Hole in highlight 
    Hello everyone,
    My camera was rented to shoot sunrises and sunsets in El Salvador, and every single shot of the sun had what looked like a hole in the image. This was visible on the LCD as well. I was shooting 3K in Raw view at 60 fps. I switched the camera to 4k and different frame rates, but nothing changed.
    Anyone have any idea of what this could be? Is it a damaged sensor, software issue? Here is a sample of what it looks like.
    This is the first time I shoot straight into the sun with the camera.

    Thank you.

    RED ONE SN# 5771
    Build 20.1.6
    Attached Images
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  2. #2  
    This is a known issue with CMOS sensors. You need more ND if you want to shoot sunsets. This can be easily fixed in color correction, but the "black disk" is what CMOS sensors do when they clip.

    A CCD could have vertical smear, a CMOS produces a black disk, even in some DSLRs.

    David
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    A revolution is a struggle between the future and the past." – Fidel Castro
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  3. #3  
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    ND won't always be what you want if you want detail elsewhere. Where the clipping occurs will be peak white, so just track in a peak white circle.
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  4. #4  
    The "black hole sun" in this shot isn't that bad. Methinks you could actually pull the top of your curve a fuzz and roll it off. No tracking required. As a quick check, bump your ISO up a level or two in REDCINE and see if the spot disappears, that will let you know if you can CC it out.

    An IR filter can also help when shooting similar scenes.
    Last edited by Jeff Kilgroe; 01-23-2010 at 12:26 PM.
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  5. #5  
    I appreciate the feedback guys. Fixing it is no the problem, I would like to avoid it altogether. After all we pay a lot for this camera and I would like to find a definite solution to this if there is one.
    I have shot scenes before where I can actually see a light source and this has never happened. I also own a Digital Still Camera, a canon G10 (CMOS sensor) and shoot toward the sun all the time and never had this issue, which leaves me thinking that a way more sophisticated and expensive camera like the Red One should not cause this.
    Has anyone had this specific issue?
    I tried messing with the curve and had no change, the "hole" always remains the same in shape and intensity.
    Thanks a lot.
    Federico
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  6. #6  
    Senior Member jimhare's Avatar
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    Yes, it has to be really intense. I shoot at lights all the time and don't encounter it. The sun is a sure fire way to bring it out!

    It's a very well known issue and there is currently no fix, nor have I heard of one potentially coming.

    My advice is to find ways to work around it as it's unlikely it will change.
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  7. #7  
    This is a CMOS sensor issue as mentioned above. All CMOS sensors suffer from overload at some point. And that's just what the black spot is, is overloaded photosites. The trick or solution is what is done with the overloaded photosite data. In most DSLRs, you don't run across this sort of issue because your shutter speeds under such conditions are typically a lot faster, so you're not as likely to overload. And also because even though Canon, Nikon and others shoot "RAW" they still perform a significant amount of image processing in-camera and will take overloaded site data and specifically mask it to 100% luma. The RED One doesn't work that way, it doesn't do any processing of the image in-camera, you get the RAW sensor data right there in the R3D file.

    But that said, I can reproduce this same issue with a couple of my Nikon DSLRs, a Canon G9 and another Fuji digital camera. I haven't tried to duplicate with the 7D or 5D2, but I've heard reports of this showing up on the 7D. I can also show you shots of security cameras and other CMOS imagers that have this problem as well. It's a CMOS issue.

    I'm surprised this spot isn't pulling out with a little CC, but I also don't have the RAW file in front of me to study.

    The "fix" for this anomaly is to process the image data in post, much as a other cameras would do this for you. Which means mask out those blown pixels. Or track and cover.
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  8. #8  
    Thank you all, the information was very useful!
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  #9  
    Red Team Deanan's Avatar
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    BTW, Mysterium-X doesn't have this issue.
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  10. #10  
    Senior Member Stephen Williams's Avatar
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    Quote Originally Posted by Deanan View Post
    BTW, Mysterium-X doesn't have this issue.
    That's very good news.
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