Raw conversion - when to make adjustments?

08/03/2006 07:05:27 AM · #1

Hey all, i've just noticed something with RAW conversion, and that is that increasing contrast, saturation etc also increases noise significantly in the image. I'm using the RAW plugin on adobe PS CS2

Is it better to get the raw output image with neutral contrast, saturation, and no sharpening, and then do all these adjustments in photoshop? Of course i'm guessing playing with exposure and white balance is ok in RAW edit?

The reason why i thought it is better to do the edits after raw output is that I usually noise reduce photos first, and then do saturation etc.

Feedback?

Makka

Canon EOS-5D Mark II

08/03/2006 07:10:02 AM · #2

I use RawShooter for my RAW processing. I've never really noticed much in the way of noise when I do processing. I normally just adjust colour balance if I need to and play with the contrasting. If I want to I'll hit the saturation a little. I found that using the sharpening option in RawShooter gave me a few artifacts here and there so I don't use it now.

dwterry

Canon EOS-1D Mark III

08/03/2006 07:56:04 AM · #3

Any time you adjust WB, exposure, or contrast, you're potentially throwing data away. So... if you can do it in RAW before converting to 8-bit mode, you'll have more / better quality data to work with at the PS editing stage.

On the other hand, if you take your RAW image and either convert to a 16-bit tiff or, in the case of PSCS, tell it to convert the raw file in 16-bit mode as it goes into the editor, then I think it really doesn't matter so much. Feel free to do all of your adjustments in PS in 16-bit mode.

Here's what I do... for quick proofs, I use RawShooter Premium and let it do all of my adjustments (contrast, saturation, exposure, white balance and sharpening). The quality of the images coming out of RSP is high enough that I don't even load the image into PS. It goes straight to the web for my customers to see.

On the other hand, when they purchase a 16x20" print, I go back and re-process the file in 16-bit mode (without the sharpening, and often with less contrast and other adjustments used in the original) then take the file into PSCS to finish it off.

Message edited by author 2006-08-03 07:57:05.

kirbic

Canon EOS R5

Canon RF 24-70 f2.8 L IS

08/03/2006 07:59:12 AM · #4

It's normal for you to see the noise more easily afterincreasing contrast. Increasing saturation can make color (chroma) noise more apparent as well. Your contrast and saturation adjustments should be done in RAW conversion though. Doing them in JPEG later will just tend to generate posterization. There are a couple ways to minimize noise:
- Expose to the Right
- Use the lowest practical ISO

When processing, avoid strong boosts in exposure in shadow areas; that will make noise very visible. Use selective NR in post processing so you only apply noise reduction where it's needed.

08/03/2006 09:13:28 AM · #5

I find that using Noise ninja, then applying contrast adjustment leads to less image degradation than the other way around, and as such, i'm wondering if contrast adjustment is better done in photoshop after noise ninja, OR is raw adjustment of contrast much better?

thanks

oh, and thanks for the expose to the right trick kirbic, will have to give that one a go :)

oh yea, and also for reference, i usually output raw --> 8bit TIFF files. I'd love to do 16 bit TIFF files, but when i tried, any photoshop adjustments take waaay to long to be practical ... anyone wanna buy me a new comp? :P

Canon EF 24-105mm f/4.0L IS

08/04/2006 09:11:38 AM · #6

bump :)

fotomann_forever

08/04/2006 09:33:41 AM · #7

FWIW, in my workflow... I input the flattest image possible into PS. Contrast and Saturation in ACR are both set to 0 and the curve in ACR is set to linear. Also, unless there is something obviously wrong with exposure all other settings are 0 (exposure, highlights, shadow etc.) I rarely process an image that needs over 1 stop correction because of the noise that introduces.

In my opinion, bringing a flat 16bit image into Photoshop gives me the most flexibility in post and less chance of artifacting and banding. I also often process my portraits with Alien Skins Exposure (film simulator) and having a flat image to start seems to work better for me.

tribal

Canon EOS-6D

08/04/2006 10:17:17 AM · #8

right on some good techniques i'm gonna have to bookmark

dwterry

Canon EOS-1D Mark III

08/04/2006 10:19:49 AM · #9

Originally posted by diablo2097:

i usually output raw --> 8bit TIFF files. I'd love to do 16 bit TIFF files, but when i tried, any photoshop adjustments take waaay to long to be practical

You're right. Processing a 16-bit file in PhotoShop definitely requires more horsepower under the hood. And so it's okay to process 8-bit instead of 16-bit. It's just, as recommended already, if you output 8-bit (whether jpeg or tiff), you want your exposure, wb, contrast "at the time of conversion" to be as close to what you're going to want in the end as possible.

But if you output 16-bit, then either way works, you can output a completely flat file and do all of your adjustments in photoshop where you have more control.

08/04/2006 10:36:09 PM · #10

awesome, thanks for the help guys... if i get around to id, i'll try to do some sort of comparitive test once i get some work outta the way :P

oh, and out of curiosity, anyone here use a P41.6Ghz computer and manage to use 16 bit raw files? just checking if its just me or the comp :P

thanks

dwterry

Canon EOS-1D Mark III