5D Mark iii LCD Brightness purple glare affecting image?

[Radjan]

Hi,

Saturday I discovered a problem with my 5D mark III for the first time since buying it in mid 2013. I have always run 'auto' brightness on the rear LCD, as it has worked perfect. Before a wedding session for a friend, I ended up changing my brightness to full, because I knew it would be a very dark venue, and wanted to try it out. I also changed my max auto ISO to 25600 from 12800, just in case it was needed. I used a 24-70 2.8 II all night.

Halfway through the evening, I had a break, and carefully inspected some photos, and noticed a purple glare in the lower right corner of the LCD, that I had never seen before. After some troubleshooting, I found out the purple glare only occured at 25600 ISO. I tried to think of what I had changed earlier, and checked to see if it had something to do with the rear LCD brightness. If I turned down the brightness (or set it to auto) - the purple glare dissapeared. Likewise, it only seemed to appear noticable at 12800 or above ISO. I had heard about the 'LCD Light leak issue', and figured my body might suffer from this, but after reading about it today, I can see that it has nothing to do with my problem, as it is an entirely different issue.

Has anyone experienced something similar? Or can anyone try shooting an image with full brightness and at 25600 ISO? I have checked around various sites, and can't really find a mention of this, so I'm thinking it may just be my body that is affected.

See photos below. First one is shot at 25600 ISO at full brightness on LCD - only turned up exposure in lightroom. Second is SOOC.


https://www.flickr.com/photos/roadske/13697213364/
https://www.flickr.com/photos/roadske/13697222304/

 

[Grant Atkinson]

Hi Radjan, interesting post. I will try shoot a few frames tonight with my 5d3 and let you know how it goes..
Cheers
Grant

 

[pedroesteban]

Radjan,

I´ve always had this problem with my 5d mk III, while shooting at ISO 12800 and 25600. Most times it's too faint to be noticeable at ISO 12800, but it's always noticeable at ISO 25600. Since I bought my camera in the US but live in Brazil, I couldn't send it back for an exchange. If I lived in the US, I would certainly have sent it back.

My hope is that this is somehow related to peripheral illumination correction and will be corrected in a future firmware update, even though this purple glare shows up in RAW files.

 

[U-Type]

I can confirm this problem with my 5D as well, usually appears in ISO 25,600 or above. I don't really know why but I don't mind it that much since I don't usually shoot that high anyway

 

[Radjan]

It's definately got something to do with brightness on the rear LCD, atleast in my case. Whether peripheral illumination also affects it, I dont know, but I will try test tonight.

If I turn brightness all the way down, and shoot at ISO 25600 - I can barely notice it - at full brightness and 25600, I can easily see it.

At lowest brightness at 12800 ISO - I can't tell at all - but If I turn up brightness to full, I can see it at 12800, although it isnt as bad as it is at 25600.

Also, I never noticed it with auto ISO turned on, but I suspect that's because in very dark environments when the ISO needs to be at 25600, the brightness is automatically turned down by the auto function.

- Radjan

 

[YuengLinger]

I'm curious--Why would you want to have the brightest setting in a "very dark venue"? I always thought the darker the ambient, the lower the LCD brightness.

Outdoors, bright day, sometimes no choice but to go to brightest...

And are you talking about shooting with Live View? Otherwise, how does LCD display come into play during exposure?

 

[Loswr]

I'm curious--Why would you want to have the brightest setting in a "very dark venue"? I always thought the darker the ambient, the lower the LCD brightness.

+1 - the dimmer the ambient light, the dimmer the LCD needs to be. Regardless, the LCD brightness has nothing to do with the issue at hand.

The phenomenon in question is 'amp glow'. Google away...

 

[Radjan]

It's not something I normally do. It was a case that I wanted to try using manual full brightness on the rear LCD, and see how it was. I would never have guessed that it would affect the actual images I took. Rear LCD brightness should'nt have anything to do with how your images turn out.

I'm not talking about live view, or exposure. I'm simply turning my ISO up to 25600, and taking a picture. With brightness on the rear LCD turned all the way up to full, the result becomes the purple glow in the bottom right corner. Turn brightness down, or on auto - where it automatically turns it down due to the dark venue - and the problem almost dissapears. I guess turning off auto-preview of images taken might also remove it completely, as the rear LCD then isnt on at all when pictures are taken? Maybe, I'm just speculating.

I've googled amp glow, and I can definately see the similarities. What I found though, was that my images at 25600 with full brightness on rear LCD cause this problem badly, but with brightness turned all the way down, its almost gone. The glow must, by my reasoning, be coming from the rear LCD leaking some form of light onto into the image? And maybe the rear LCD brightness is the crutch for the amp glow problem? I'm not sure.

Whatever it is with my body, the problem is fixable by either having auto brightness on, or turning down LCD brightness, and maybe also auto-preview off. I just find it odd that the rear LCD can have an impact on images taken.

 

[Loswr]

I've googled amp glow, and I can definately see the similarities. What I found though, was that my images at 25600 with full brightness on rear LCD cause this problem badly, but with brightness turned all the way down, its almost gone. The glow must, by my reasoning, be coming from the rear LCD leaking some form of light onto into the image?

Interesting. Actually, it's not unprecedented - I recall reports from an earlier body (not sure which one) that turning on the light for the top LCD affected the image during long exposures. Roger at Lensrentals has shown that light leaks in around the lens mount, and apparently these cameras aren't light-tight on the inside, either.

At least you have a workaround!

 

[Radjan]

Yes, and the work-around isnt even troublesome, so its not a big issue - auto brightness works great for me - and I do love the camera. People just need to be aware of the problem - if it truly is a general problem and not just my body - noone wants ruined shots if they can avoid it

 

[Mt Spokane Photography]

Yes, and the work-around isnt even troublesome, so its not a big issue - auto brightness works great for me - and I do love the camera. People just need to be aware of the problem - if it truly is a general problem and not just my body - noone wants ruined shots if they can avoid it

You are using Live View?

I did not see mention of this, but the LCD is normally not on unless you are in live view or video mode. In a very dark room, light from a fully bright LCD could be leaking in to the lens or sensor.

I'd suggest sending it into Canon if its a issue for you along with sample images, and a full explanation of how to repeat the issue. (They have lots of black tape in stock to repair light leaks )

Its pretty difficult to keep light sealed totally out of a super sensitive sensor, the LCD has a bright light illuminating it, and electrical terminations just might be attached to that lower corner allowing light to leak. It seems to me that they should be willing and able to fix that. Who knows, maybe its one of the unpublished fixes that they do if someone complains.

I'd suggest discussing this with several of the Camera reviewers. They might be willing to do a controlled test, and if they report the issue, then there will be a fix.

I'll try mine if I have a chance.

 

[pedroesteban]

Since I shoot exclusively through the viewfinder, which means my back LCD is never on while I'm shooting, I guess my case is worse than Radjan's. Maybe it's because of ambient temperature. Most of my extreme low light shots taken with the 5d mark iii were during carnaval in Rio, and according to what I googled (Thanks, neuro!) "amp glow" seems to be related to sensor temperature.

Does anyone here know if a software fix (or at least an improvement) is possible?