Canon Community Canon Community
 


Reply
Occasional Contributor
Posts: 7
Registered: ‎07-14-2017
Accepted Solution

Grossly over exposed images during rapid shooting Canon Mk III

Recently I had a problem with my new Canon 5D Mk III. My passion is photographing birds in flight and suddenly and ocasionally during rapid shooting the images are grossly over-exposed. I use manual exposure of 7.1 or 8.0, Auto ISO, High-speed continuos shooting, AI Servo AF mode and AF area selection.

The images below illustrate tha issue. All of a sudden the ISO shoots up from 800 in normally exposed images to 12800

in the over-exposed photos?

Has anyone experienced the same problem and if so how was it resolved/

 

_MG_1871Kgalagadi 06_17.JPG_MG_1892Kgalagadi 06_17.JPGNormal Exp.JPGOver Exp.JPG

 

 

 

 

 

 

Esteemed Contributor
Posts: 2,150
Registered: ‎11-14-2012

Re: Grossly over exposed images during rapid shooting Canon Mk III

I stopped using Auto ISO because it's not very consistent in picking a "Best ISO" for most situations. It seems to favor allowing a high SS over everything else.

"A skill is developed through constant practice with a passion to improve, not bought."
Occasional Contributor
Posts: 7
Registered: ‎07-14-2017

Re: Grossly over exposed images during rapid shooting Canon Mk III

Thank you for your advice. Would you say the ISO jump is an inherent fault of the Camera, and how is it resoled?

Esteemed Contributor
Posts: 2,150
Registered: ‎11-14-2012

Re: Grossly over exposed images during rapid shooting Canon Mk III

I don't have that body but I'd say it's the fault of the software wrote to instruct the full line up of bodies with Auto ISO.

"A skill is developed through constant practice with a passion to improve, not bought."
Respected Contributor
Posts: 1,769
Registered: ‎02-26-2015

Re: Grossly over exposed images during rapid shooting Canon Mk III


Bundu wrote:

Recently I had a problem with my new Canon 5D Mk III. My passion is photographing birds in flight and suddenly and ocasionally during rapid shooting the images are grossly over-exposed. I use manual exposure of 7.1 or 8.0, Auto ISO, High-speed continuos shooting, AI Servo AF mode and AF area selection.

The images below illustrate tha issue. All of a sudden the ISO shoots up from 800 in normally exposed images to 12800

in the over-exposed photos?

Has anyone experienced the same problem and if so how was it resolved. 

 


I use Manual exposure mode with Auto ISO all the time on my 7D Mk II with no issues. 1/4000 is about twice as high a shutter speed than you need for birds in flight. I don't see that causing the issue so that was more of an observation.

 

The date stamp on the two photos are 5 minutes apart and the numbering indicates they are 10 frames apart. It might be more helpful to see the photo immediately preceding the overexposed one. 

Occasional Contributor
Posts: 7
Registered: ‎07-14-2017

Re: Grossly over exposed images during rapid shooting Canon Mk III

_MG_0546Kgalagadi 06_17.JPG

 

_MG_0547Kgalagadi 06_17.JPG_MG_0548Kgalagadi 06_17.JPG_MG_0549Kgalagadi 06_17.JPG

 

Above is a sequence of for images all taken at the same burst on TV prioity, the details for the first and second above are depicted below. The same story for the 3rd and 4th as far as the iso jumping from 640 to 12800 then back to 640 for the last image.

In the previous example of flying birds I have normally exposed images following imediately after the overexposed images taken at the same time

 

 

Lion Normal1.JPGLion over-ex 1.JPG

 

I look forward to your comments.

 

Respected Contributor
Posts: 1,852
Registered: ‎02-17-2016

Re: Grossly over exposed images during rapid shooting Canon Mk III

You really need to try it in manual mode so that there is no autoexposure.

 

The only thing I can think of is that there is a loose flap of something that occasionally covers the exposure chip when the mirror is moving rapidly.

 

You might take the lens off, put the camera in cleaning mode and look inside to see if you see something.

Honored Contributor
Posts: 5,038
Registered: ‎08-13-2015

Re: Grossly over exposed images during rapid shooting Canon Mk III

I had a similar issue with random over/under exposures.  I never really figured it out, because it seemed to resolve itself when I started using back button focus.  My best guess is that my thumb had nothing to do, so it may have hitting Exposure lock button.

----------------------------------------------------------------------------------------------------------------------------------------------------------

"I don't rent software. I use Photoshop CS6, ACR 9.8 and Lightroom 6.8 ."
Respected Contributor
Posts: 1,769
Registered: ‎02-26-2015

Re: Grossly over exposed images during rapid shooting Canon Mk III


kvbarkley wrote:

You really need to try it in manual mode so that there is no autoexposure.

 

The only thing I can think of is that there is a loose flap of something that occasionally covers the exposure chip when the mirror is moving rapidly.

 

You might take the lens off, put the camera in cleaning mode and look inside to see if you see something.


I agree it could be that the mirror is sticking up, which would keep light from reaching the metering sensor.

Occasional Contributor
Posts: 7
Registered: ‎07-14-2017

Re: Grossly over exposed images during rapid shooting Canon Mk III

Thank you for your comments and suggestions.

Yes I do use manual for flying birds, normally an F stop of 7.1 or 8, and Auto ISO  - these are illustrated in the first images where the ISO set at 800 for the normally exposed and then suddenly jumped to 12800

In the next sequence I used TV -shutter priority @ 1000. the normally exposed image F7.1 and ISO 640, and the next photo adjusted the exposure to F6.3 and the ISO jumped to 12800.

So it happened in rapid shooting both in manual and shutter priority?

powered by Lithium

LIKE US on Facebook FOLLOW US on Twitter WATCH US on YouTube CONNECT WITH US on Linkedin WATCH US on Vimeo FOLLOW US on Instagram SHOP CANON at the Canon Online Store
© Canon U.S.A., Inc.   |    Terms of Use   |    Privacy Statement