Live View and noise

[Wayne Fox]

I like Live View for critical focusing when using my 1DsMk3 and 5DMk2 on a tripod.  I also have used it for framing when I have the tripod elevated for a better camera angle - I am somewhat vertically challenged.

Like others, I have some concern that the energized sensor for Live View will create enough heat to add noise to an image.  I decided to try a little test just to see if there was a way to validate this or if indeed Live View doesn't add any significant noise.  I think to really determine it full scale would require a lot more tests, varying the ambient temperature, exposure times, ISO etc.  But I decided to do a basic test to get an idea.  Anyone have any feedback on my method (am I out in the night on this) or what I've found let me know.

Setup was pretty simple.  5DMark2, inside at room temperature.  Body cap on camera, viewfinder covered.  A series of exposures, each 1 second long at IS0 100.  First exposure is before live view is enabled,  then with Live View on, 1 exposure each minute for 5 minutes.

The images were brought into LR, all adjusted to 0 black, +4Ev to exaggerate noise.  Then opened as one stacked document in Photoshop, where I did a screen grab of the histogram for each layer.  I then cropped to a 250x250pixel image from the middle and have show that at 100%.

Here is what I ended up with ... it appears even after 5 minutes there isn't any significant difference.

[attachment=11673:LiveView...cCompare.jpg]

[button]

Thanks, Wayne.  That's good to know.

John

[francois]

I always wondered about that issue. Thank you Wayne for doing this test and sharing your results.

[james_elliot]

Not absolutely true, as I already said in an another thread.
In live view there is slightly more noise. This is what you get at ISO 6400:
[attachment=11682:iso_6400n.gif]
That's unavoidable. However performances are indeed remarkable, as noise increase is almost unperceivable.

Full results (for all ISO) and explanations of the diagrams are there:
http://www.photo-lovers.org/fpsensor.html.en

I like Live View for critical focusing when using my 1DsMk3 and 5DMk2 on a tripod.  I also have used it for framing when I have the tripod elevated for a better camera angle - I am somewhat vertically challenged.

Like others, I have some concern that the energized sensor for Live View will create enough heat to add noise to an image.  I decided to try a little test just to see if there was a way to validate this or if indeed Live View doesn't add any significant noise.  I think to really determine it full scale would require a lot more tests, varying the ambient temperature, exposure times, ISO etc.  But I decided to do a basic test to get an idea.  Anyone have any feedback on my method (am I out in the night on this) or what I've found let me know.

Setup was pretty simple.  5DMark2, inside at room temperature.  Body cap on camera, viewfinder covered.  A series of exposures, each 1 second long at IS0 100.  First exposure is before live view is enabled,  then with Live View on, 1 exposure each minute for 5 minutes.

The images were brought into LR, all adjusted to 0 black, +4Ev to exaggerate noise.  Then opened as one stacked document in Photoshop, where I did a screen grab of the histogram for each layer.  I then cropped to a 250x250pixel image from the middle and have show that at 100%.

Here is what I ended up with ... it appears even after 5 minutes there isn't any significant difference.

[Wayne Fox]

Not absolutely true, as I already said in an another thread.

Don't think I said absolutely

In live view there is slightly more noise. This is what you get at ISO 6400:
[attachment=11682:iso_6400n.gif]
That's unavoidable. However performances are indeed remarkable, as noise increase is almost unperceivable.

hmmm, I said insignificant, you said almost unperceivable.

Insignificant (to me) -> I don't believe in any side by side tests of normal images there would be a visible increase in image noise.  I'm not quite sure what you mean by almost unperceivable ... are you saying you believe you could see a difference in actual images?

Comparing Live View noise at ISO 6400 to me personally isn't very valuable.  Doubtful at those ISO's I"m using tripod, mirror LU and Live View 10x focusing.  If I'm at 6400 I've already decided noise is unavoidable to get the shot so I'm not very concerned with an almost unperceivable increase, and more than likely I'm hand holding, so no Live View anyway.  

I looked at the charts at ISO 100.  It appears Live View graphs are slightly different but so small as to be barely measurable..  How long has Live View been active in those tests?

[james_elliot]

Insignificant (to me) -> I don't believe in any side by side tests of normal images there would be a visible increase in image noise.  I'm not quite sure what you mean by almost unperceivable ... are you saying you believe you could see a difference in actual images?

There might be a difference in deep shadows. But you're absolutely right: I don't think it matters for "normal" shots.

Comparing Live View noise at ISO 6400 to me personally isn't very valuable.  Doubtful at those ISO's I"m using tripod, mirror LU and Live View 10x focusing.  If I'm at 6400 I've already decided noise is unavoidable to get the shot so I'm not very concerned with an almost unperceivable increase, and more than likely I'm hand holding, so no Live View anyway.  

I looked at the charts at ISO 100.  It appears Live View graphs are slightly different but so small as to be barely measurable..

These are the 100 ISO and 400 ISO curves. Differences exist: the curves are slightly shifted to the right, but the difference is less than 1/10 of a bit.
[attachment=11698:iso_100n.gif]
[attachment=11699:iso_400n.gif]

How long has Live View been active in those tests?

10 minutes

Friendly

JMA

[Hening Bettermann]

Thanks to the both of you for conducting the tests and sharing this valuable info!

[Wayne Fox]

There might be a difference in deep shadows. But you're absolutely right: I don't think it matters for "normal" shots.



These are the 100 ISO and 400 ISO curves. Differences exist: the curves are slightly shifted to the right, but the difference is less than 1/10 of a bit.
[attachment=11698:iso_100n.gif]
[attachment=11699:iso_400n.gif]


10 minutes

Friendly

JMA

Just curious if you have tested this at short intervals.  I'm guessing when I'm using Live View it isn't active for more than 30 seconds at a time.  It appears at low ISO even after 10 minutes the difference is extremely small ... I'm not sure you would even see a visible difference in dark shadows, especially on a print.

Wayne

[marcmccalmont]

A little off topic but I am finding live view with a focusing cloth, my reading glasses and manual focus a great tool
I'm glad to hear I'm not increasing noise.
Marc