Canon 1D mark 4 RAW highlights issue..
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dbmdb
Registered: Aug 12, 2012
Total Posts: 4
Country: United Kingdom

I've had a Canon 1D mark 4 for about 4 months now, and photographed a concert for the first time using this camera during the week. There were some fairly intense blue and red lights aimed at the musicians.

I chose to record CR2 RAW to the CF card, and JPEG L to the sd card. The problem I am having is that while the JPEGs seem to render the highlights as they should be, the highlights are completely blown on the raw images. Without trying to describe it further, I think the best thing is to give examples, so here we are:












and












Having not heard back from Canon yet, I am getting rather worried about it, as I have more work on the concert front coming soon.

I would really appreciate any input or advice from you really knowledgeable people out there.

Thanks in advance.

David


Dennis M 1064
Registered: Jun 29, 2012
Total Posts: 420
Country: United States

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dbmdb
Registered: Aug 12, 2012
Total Posts: 4
Country: United Kingdom

Dennis thanks, but the trouble I had was the lights were changing colour quite rapidly and also moving direction. I didn't set a custom white balance due to this and opted for AWB instead guessing that I could recover things to an extent later in RAW editing. I shot in manual, with spot metering to ensure my subject was in focus at F2.8 with IS, auto ISO, with varying shutter speeds.

My experience in shooting RAW is ok I guess, though having not shot concerts before, mostly sport and landscape, I've not previously experienced this "unpredictable" type of light. The highlights on the RAW images appear not to be there, and cannot be recovered in post processing. Instead I have this rather odd neon type effect on the RAW images. The Raw conversions I've shown are straight conversions to jpeg without any alteration/ post processing aside from my watermark. Believe me I did try to recover things in post processing to no avail.

So is this something I will have to expect when shooting in this type of lighting with the 1D mark4, it seems rather odd to me that the RAW images are being recorded in this way?! Is it perhaps a flaw?

It may well just be me, but something doesn't seem right about it. I guess it would be good to know if there is anyone who has experienced this same issue with the 1D mark 4 in these type of shooting conditions?



Dennis M 1064
Registered: Jun 29, 2012
Total Posts: 420
Country: United States

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Dennis M 1064
Registered: Jun 29, 2012
Total Posts: 420
Country: United States

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dbmdb
Registered: Aug 12, 2012
Total Posts: 4
Country: United Kingdom

Sorry Dennis, I'm saying post processing, but I mean the RAW conversion process. I've had a rather long night as it is festival time here in Edinburgh.

The top image of each is the RAW with the bottom being the Jpeg. In the first image there was no white light only blue and red.

I am by no means the most knowledgeable person on this subject, and I understand what you are saying about the binned data in JPEGs. I've just not experienced this effect with RAW ever before. Obviously something isn't right, I think possibly using spot metering wasn't the correct thing to do in hindsight.

I guess I am about to get a kicking when the "real photographers" get out of bed!



Dennis M 1064
Registered: Jun 29, 2012
Total Posts: 420
Country: United States

Hey, I was referring to me!!! I was just driving to the grocery store when I realized how that sounded. Sorry mate. Didn't mean you.



markd61
Registered: May 26, 2009
Total Posts: 464
Country: United States

The problem is the colors in theater lighting. Lately I have seen a lot of LED lighting that has a color gamut that is way out of the ability of the sensor to capture it. That being said, I do agree that you should be able to recover it from the RAW file as it generated the jpeg in the camera.

I would suggest pulling down the saturation slider a bit before slamming the highlights slider over as much as possible.
Are you using Lightroom? Ver 4 really handles these highlights well.

As for metering, meters can be confused by different colors. A good reading can still allow a blown highlight in a certain color. Thus looking at the histogram is useful despite what the meter says.



dbmdb
Registered: Aug 12, 2012
Total Posts: 4
Country: United Kingdom

Dennis I didn't take offence at all, so don't worry.

I've been able to recover to a point by slightly desaturating blues and aquas. Though I must say it can leave some rather odd blob style artefacts in the affected area of the images given the intensity of the coloured light. Which would absolutely confirm your point on colour gamut Mark.

Thank you for the advice on using the histogram both of you. Can I just ask on this point then, how would you be more mindful of the histogram in a situation where multiple lights pointed at the subject are rapidly changing colour, is this going to be an effective solution?

I was thinking of obtaining a custom white balance based on the reflection of these particular problem colours produced by the lights (blue through magenta and red) on a specular part of, for example some ones skin or whilst shone on something that produces quite an intense specular highlight. Might this be the best way to solve the problem? Just a thought.



markd61
Registered: May 26, 2009
Total Posts: 464
Country: United States

What I do is slightly underexpose if I know there is peril to the highlights because of changing conditions. I try to set a basic exposure and stay there and chimp to make sure I am not clipping. If things drift one way or another a stop over or under usually gets it unless there are crazy lighting changes. That does happen.

Another point; Set your camera to half stop steps not third stop. Third stop adjustments are nearly useless and slow you down when you need to make adjustments in such crude lighting.

I would go so far as to say that third stops are useless outside tabletop photography and even then a JPG can be tweaked that much without penalty in post.
People are too preoccupied with noise in the shadows. The fact is that this is a naturally high contrast situation and some blowout of highlights can be accepted.

You can safely open the shadows up by quite a bit on most cameras and certainly the Canon.

Custom WB is a waste of time in this situation. If you are shooting RAW you can try to get closer by WB clicking on an area in the image. But lets be clear, the lighting engineers planned to make this scene very abstract. This ain't a classical concert. IF I were going to click WB I would do that on his shirt on the right as it seems to be lit by white light. When you do that you will see how deeply saturated the blues and other colors are.



markd61
Registered: May 26, 2009
Total Posts: 464
Country: United States

If you can upload the RAW somewhere I will process it the way I would and you can see what I have done.



Gary Petersen
Registered: Sep 29, 2003
Total Posts: 5392
Country: United States

If the in camera jpeg converter can do it then ACR should be able to also. I'd say it's in your post work somewhere.



rhyder
Registered: Jul 10, 2004
Total Posts: 3785
Country: United States

Gary Petersen wrote:
If the in camera jpeg converter can do it then ACR should be able to also. I'd say it's in your post work somewhere.


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