1D mk II struggling with REDs or is it me?

[martcol]

Wow! Over the weekend I took some close up shots of BRIGHT RED tulips. Most of the frame filled with Bright, bright Red. I was just playing really but trying to process these is like, a nightmare. I'm shooting with a 1D Mk II and 24-70 L lens so, hopefully no problem there but I just can't get anything like the red on screen.

I notice the red channel on the histogram is in a world of it's own but looking at the picture it's as though the red is hopelessly overexposed yet, the overall exposure of the image is fine... No clipping at all in the histogram.

Am I losing it?

Thanks

Martin

[Steven M. Anthony]

No. I read an article recently--can't remember where--that talked about the Canon CMOS (maybe others', but the guy who wrote the article had used a Canon) going a bit haywire with intense reds. I'd experienced it with tomatoes and figured I'd done something wrong. Not much you can do about it. I think he mentioned toning down the red channel. Can you do that in camera? I don't think it's an option for a 10D.

[KennyG]

Martin, you have to be careful when shooting flowers as the colour spectrum is designed for insect eyes, not human's. A good example is some of the pansy family that look purple but come out blue.

I am guessing here as I have no proof, but it appears that due to the strange colour spectrum it causes the red channel to appear to be blown out, or greatly over-saturated. If you take a picture of a similarly bright red object, but a one that is painted, you will find there isn't a problem.

Next time, try shooting in RAW which will give you more control over the individual channels. Also, try the different matrix settings, taking a shot in each and comparing them. You can apply the matrix settings in some RAW converters by using the 'as shot' settings.

[scottbergerphoto]

The Red prooblem with the 1D M2 is a well documented issue that occurs with jpeg and sRGB. You can eliminate the problem by shooting Raw and Adobe RGB.
http://www.photography-on-the.net/forum/showthread.php?t=56304&highlight=overexposed+reds

[Moments]

I brought up the problem with bright reds with the 1D MarkII with a Canon tech at a trade show a few weeks ago. He side stepped the question for a while, then did say he saw the problems himself a few times, and then, with no answers or suggestion as to fixing or helping the problem, tried to move on to a different topic .
As Scott says, Raw and AdobeRGB seems the way to go to help out the problem.

[Jon]

As KennyG said, many flowers are strong UV reflectors, and have different markings in the UV than they do in the visible spectrum so they can better lure insects. If the sensors are vulnerable enough to this UV for it to markedly affect the colour, it would seem to put paid to the question about whether to use a UV filter or not. Anyone up for a test? And would we find, as is the case in IR, that some lenses are more susceptible than others to this?

[Webster]

The Red problem with the 1D M2 is a well documented issue that occurs with jpeg and sRGB. You can eliminate the problem by shooting Raw and Adobe RGB.
http://www.photography-on-the.net/forum/showthread.php?t=56304&highlight=overexposed+reds

I thought that if you shoot RAW, the color space setting in the camera doesn't matter. Is this true? If so, how about RAW and ProPhoto or some other large gamut space?

[Jon]

RAW is just what it says - the straight, unadulterated data from the sensor. Any conversion to a viewable picture imposes some colour space on it, be it sRGB, Adobe, or other. The results will vary, but if, for whatever reason, a sensor isn't sensitive enough to a particular colour, you'll be hard-pressed to find a stock colour space that will give good results. This is one of the reasons you'd want to profile your equipment and get a specific colour profile for each component - so the system knows how to translate what the sensor captured to what it paints up on the monitor, or it sends to the printer.

[martcol]

Well, I do shoot RAW and have a callibrated system and conver with CO using specific camera profile. I did neglect to set the colour space to AdobeRGB so have switched away from sRGB. I had a bit of a chance to take a few more shots of the tulips and though better, still appear a bit blown out!

Regards

Martin

[cactusclay]

That sounds bunk. Is Canon planning on fixing that problem?

[jyrgen]

I read a nice article (http://62.65.193.159/foto/icc/piiramine.html) on this subject, but it's only in Estonian. Itry to resume it:
- it's not a Canon specific problem, rather a colour space problem
- even AdobeRGB has too narrow gamut (esp in reds-yellows), not to speak of sRGB
- solutions provided below demand shooting RAW (and have best possible camera specific input profile for RAW converter)
- solution 1: use wider gamut colour space for output from RAW converter, such as ProPhotoRGB
- solution 2: use unprofiled output from RAW coverter, which is supposedly possible with C1
- solution 3: if RAW converter defaults to AdobeRGB or sRGB, or if shooting jpg is the only possibility, try to "shift spectrum" using opposite colour filter (green, I assume). You have to correct white balance and colour casts afterwards, but you get your red details captured.

[cactusclay]

So if you don't want to shoot raw, then you are screwed.