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Canon 7D Noise and ISO settings

  |   Article, Articles and reviews, Camera testing, Canon 7D   |   2 Comments

Canon 7D Noise and ISO

Are full stop or 1/3 stop settings better for image noise



Some time ago I tested the dark frame noise for all the ISO settings of the Canon 1Ds3.

As a result I only use it at ‘whole stop ISO settings’.

I’ve got a 7D on loan from Canon and just repeated the test.

All our assorted Canon 7D information is collected together on its own page, and I’ve written several short 7D review articles about aspects of using the 7D.

12800 ISO noise

ISO noise tests with the Canon 7D

A series of shots were taken with incremental ISO settings:

100,125,160,200,250,320,400,
500,640,800,1000,1250,1600,
3200,4000,5000,6400,12800 (H)

The camera was set to manual, 1/2000 of a second and f22 in a dimly lit room

There was a lens cap on and the viewfinder was covered.

So, no light getting in. It’s -just- noise I’m looking at.

ACR (5.5) Settings:

No ACR noise reduction, no sharpening, 4 stops exposure increase (to show up noise), black level at zero.

Measuring Canon 7D sensor noise

As you can see, at 12800 ISO and 3 stops pushing of the speed (112k equiv), there is a lot of noise.

I’ve turned off any camera noise reduction too.

Those of a more exacting nature might want to repeat this with NR turned on…

I’ll just show the histogram settings below for each ISO setting.

The EOS 7D results are nowhere as clear cut as they were with the 1Ds3.

However the camera is handling sensor noise, it seems to increase much more smoothly than with the 1Ds3

100 ISO125 ISO - EOS 7D
160 ISO - EOS 7D200 ISO - EOS 7D
250 ISO - EOS 7D320 ISO - EOS 7D
400 ISO - EOS 7D500 ISO - EOS 7D
640 ISO - EOS 7D800 ISO - EOS 7D
1000 ISO - EOS 7D1250 ISO - EOS 7D
1600 ISO - EOS 7D2000 ISO - EOS 7D
2500 ISO - EOS 7D3200 ISO - EOS 7D
4000 ISO - EOS 7D5000 ISO - EOS 7D
6400 ISO - EOS 7D12800 ISO - EOS 7D

Not the obvious difference I saw with the other tests, so this camera I’ll be inclined to leave on 1/3 stop increments.

If anyone does a really thorough version of this test… please do let me know?

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  • Only just found this and hence the earlier 1Ds3 test. Prompted by it, I did similar with my 30D and 5D, and plotted RAW file size against ISO, on the assumption (fair ?) that more noise means a larger file (I did also do the +4 stops exposure in processing in Lightroom, so I could see the difference). The 5D results were just as your 1Ds3, showing dips in noise/file size at ISO 100, 200, etc. The 30D also showed this pattern, still at whole stops, but the dips are at ISO 160, 320, 640. Curious !

    Thanks for a most interesting and informative website.

    • Thanks – I know the technical validity of some aspects of my testing has been questioned, but I still feel they are a valid contribution to how people process their ‘everyday’ images.