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DavidTO
Dec-06-2004, 03:20 PM
I posted this shot in another thread, but I'd really like some help figuring out why it's so noisy. I've got a Canon 300D, and I shot this at ISO 100.

If you are interested in helping me understand this, please link to the original file (careful, it's big) and take a look at the detail. Seems awfully noisy to me. What could be the cause? Me? The camera?

http://davidrosenthal.smugmug.com/photos/12294372-S.jpg

The problem's even more apparent after doing a B/W conversion:

http://davidrosenthal.smugmug.com/photos/12338741-S.jpg

dkapp
Dec-06-2004, 03:37 PM
Just took a look at the original. I have a few questions about the picture.

Was it underexposed & lightened in post?

Was it shot as a raw, then converted to jpg or jpg from the camera?

Thanks,
Dave

DavidTO
Dec-06-2004, 03:50 PM
Just took a look at the original. I have a few questions about the picture.

Was it underexposed & lightened in post?

Was it shot as a raw, then converted to jpg or jpg from the camera?

Thanks,
Dave

Shot in RAW, used Capture One 3.6 (used to be C1) to convert. I did push it one stop when converting it. I also pushed the contrast up +28 (out of a possible 50 in the program), and also tweaked the levels: 5, .82, 252.

DJ-S1
Dec-06-2004, 04:13 PM
I haven't looked at the file and I'm no expert, but I've noticed that sometimes noise is concentrated in one channel more than others, and many times it's in the blue channel. Try minimizing the blue channel and see if the noise is better. Of course, you may need the blue for this image...:dunno

DavidTO
Dec-06-2004, 04:17 PM
I haven't looked at the file and I'm no expert, but I've noticed that sometimes noise is concentrated in one channel more than others, and many times it's in the blue channel. Try minimizing the blue channel and see if the noise is better. Of course, you may need the blue for this image...:dunno

Makes sense to me, except for the fact that the B/W version was made with the lightness channel in LAB mode--so no blue was used.

The search continues...

DJ-S1
Dec-06-2004, 04:25 PM
Ah, LAB...don't use that much yet. Still learning the basics! :D

DavidTO
Dec-06-2004, 06:16 PM
Well, I'm on the road to figuring out what it is.

Has to do with the RAW conversion.

I'll post the answer when I have a complete one, still working on it at this point.

dkapp
Dec-06-2004, 06:35 PM
Shot in RAW, used Capture One 3.6 (used to be C1) to convert. I did push it one stop when converting it. I also pushed the contrast up +28 (out of a possible 50 in the program)

This is what introduced the noise in the image. Some images hold up better to pushing a stop or two than others. Have you tried to print the image yet? I doubt you notice any noise, even at 8x10.

Dave

Andy
Dec-06-2004, 07:01 PM
you pushed one stop in the raw conversion - that will introduce noise in the blue sky.

aggressive nr on the blue sky will work fine - do it selectively just for the sky...

cheers

DavidTO
Dec-08-2004, 09:45 AM
So the answer I'm getting is that it's the fault of the JPG conversion in C1.

The noise isn't apparent if I process to TIFF, or if I use PS to convert that TIFF to JPG. Or if I do the RAW conversion in PS. I looked back and it IS on my previous shots, it's just that the clouds/sky made it so apparent on this one that I noticed it.

So, they're working on it. In the meantime, my workaround (besides living with it for most things, since it's not that noticeable in most images) is to process TIFF and the run a PS action to convert to JPG.

Stinks, I know. But I am so tied to C1 for my RAW processing (can't stand using PS for it) that it's worth it to me.

pathfinder
Dec-08-2004, 10:58 AM
So the answer I'm getting is that it's the fault of the JPG conversion in C1.

The noise isn't apparent if I process to TIFF, or if I use PS to convert that TIFF to JPG. Or if I do the RAW conversion in PS. I looked back and it IS on my previous shots, it's just that the clouds/sky made it so apparent on this one that I noticed it.

So, they're working on it. In the meantime, my workaround (besides living with it for most things, since it's not that noticeable in most images) is to process TIFF and the run a PS action to convert to JPG.

Stinks, I know. But I am so tied to C1 for my RAW processing (can't stand using PS for it) that it's worth it to me.


This brings up an interesting topic for discussion, rant or rave, and that is C1 versus Adobe RAW convertor versus Digital Photo Pro from Canon.

I must confess I have only used Adobe's Raw convertor and it is so straightforward and passes an enlarged 16 bit image into PS so easily, that I am reluctant to try any thing else, but I know there are others out there who feel strongly that Phase 1 or some thing else is the way to go.
I would be interested in listening to those opinions if they can be presented in an argument filled with light rather than heat :D
I am curious Dave, why you prefer C1 if it creates noisy jpgs, as the images I compared it to were "in camera" jpgs from 20D and from Raw files converted in PSCS. Not a flame here, but a serious interest in the reasons for your preference.

For myself - I use Adobe RAW convertor because it saves me steps in PS - I do not really have much to do with levels, curves, or color correction in PS, because I do that at the time of RAW conversion and I can enlarge the image one or two steps directly from the RAW data, and then pass that image into PS as a "16" bit image ( and yes, I know it is really 14 bits or something not 16, but that is what everyone calls it just the same!) and then I can save the image finally as a smaller, sharper psd file or a fininshed jpg. ( I rarely use tiffs - too large and not enough return relative to psd's, for me)

Is there some control or ease of use that the Phase 1 offers that I need to consider?