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Old 18-07-2012, 05:59 PM
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Question Canon 60D hot pixes, they dissapear in DPP

Just obtained 60D..
And, of course, one of the first things to check were hot pixels.
I took one raw dark shot, 30 sec at ISO1600, then I stretched the histogram quite a bit, and there was one green in the upper left corner, but it disappeared after a while from DPP window.
On the DPP menu I clicked on "Adjustments -> "Revert to shot settings" and the hot pixel was back.. only to disappear again in couple of seconds.
Obviously, DPP is removing hot pixels automatically, without elaborate settings..
But when I inspected one raw dark frame taken with my 400D, the hot pixel (on another place of course, and it was red) remained where it was, even after quite a long time.
As if only 60D raw files are affected?
Anybody knows what's going one here? Such behaviour is not documented for DPP.. at least not to my knowledge..

Apart from this one, there were no other hot pixels to stick out.. and banding was significantly fainter than that of 400D.. so I am pretty happy with this camera for now.
Waiting for some free time to test it on stars..

Last edited by bojan; 18-07-2012 at 06:13 PM.
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  #2  
Old 18-07-2012, 06:24 PM
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2stroke (Jay)
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Are you sure its not your pc monitor thats displaying pixels that way? by that i mean its the issue not your darks or software just a monitor with stuck pixels.
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Old 18-07-2012, 06:29 PM
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No way.
DPP did it - I am more than 200% sure of it. It even left a mark (small white cross) as indication something was there
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Old 18-07-2012, 06:38 PM
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MrB (Simon)
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I have noticed this too with the 60Da, was equally confused.
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Old 18-07-2012, 06:44 PM
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CapturingTheNight (Greg)
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I have noticed it with a Canon 5D Mk II in DPP as well. I'm curious about an answer too......
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Old 18-07-2012, 06:50 PM
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Or is this just because a longer time is needed to process and display a larger file?

EDIT:
Yeah.. most likely a false alarm, caused by artefact of unfinished processing. And of course, 400D raw file has different format.
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Last edited by bojan; 18-07-2012 at 07:23 PM.
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Old 18-07-2012, 07:09 PM
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Octane (Humayun)
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It's because automatic chrominance/luminance noise reduction is being applied in the third tab of DPP.

The higher the ISO, the more aggressive the reduction becomes.

Feel free to reset the sliders to 0 and click Apply. From memory you can disable automatic chrominance/luminance noise reduction in the preferences.

I have now created recipes for all my cameras now; from ISO-50 to ISO-51,200, which contains standard settings that I like, as well as the default chrominance/luminance reduction settings for that particular ISO. I now move each ISO image into its own directory under the parent date/camera directory, and blanket apply the recipe for that given ISO to that batch of images.

H
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Old 18-07-2012, 07:21 PM
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Quote:
Originally Posted by Octane View Post
It's because automatic chrominance/luminance noise reduction is being applied in the third tab of DPP.

H
Hmm, not the case here apparently...
Those setting were already at zero (it cross my mind and I tried this)
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Old 18-07-2012, 07:46 PM
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Octane (Humayun)
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Hrm!

I'm at a loss, then. It's a simple piece of software, but, very powerful.

You might want to disable ALO, though. It adds more noise in the image.

Sorry, I couldn't be much help.

H
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Old 18-07-2012, 08:59 PM
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No worries..
I checked 400D files again, this time I paid special attention to one hot pixel all the time after loading the file.. until the processing is done and the display is as it should be... and I spotted the the phenomenon as similar, only a bit less pronounced and the whole thing is happening much faster (more pixels and 14bit versus 12 bit ADC, there must be a significant difference in processing time between the two).
So it must be the (unfinished) processing..
The final result is what counts and that one is quite OK ;-)
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  #11  
Old 18-07-2012, 09:19 PM
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Yep, I notice the lag when loading my Mark II and Mark III files compared to the original 5D -- 12.8 megapixels to 22.3 megapixels. It takes a while to render properly.

H
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