Go Back   Steve's Digicams Forums > Digital SLR and Interchangeable Lens Cameras > Canon EOS dSLR

Reply
 
Thread Tools Search this Thread
Old Apr 20, 2004, 8:29 AM   #21
Senior Member
 
ohenry's Avatar
 
Join Date: Dec 2003
Posts: 1,676
Default

It's not a matter of using all of the available RAM. For some reason, I get better performance at 60% than at 70%. I got tremendous improvement in performance when I gave a portion of another diskdrive (even though it is a slower drive) dedicated strictlly to being a scratch disk. I partioned off 10M and labled it z drive and use it strictly as scratch.

And no, I'm not using hyperthreading. It's an older P4 (but I have been thinking of upgrading yet again )
ohenry is offline   Reply With Quote
Old Apr 20, 2004, 11:31 AM   #22
Senior Member
 
Join Date: Dec 2002
Posts: 5,803
Default

I've got some more editing to do tonight, so I'll give that a try and see what happens.

I've heard some serious problem with having more than 2G of ram on a system with PS CS (really bad things that make PS unusable) so this might be related to that.

I'll post a followup after I try it.

Eric
eric s is offline   Reply With Quote
Old Apr 21, 2004, 12:33 AM   #23
Senior Member
 
Join Date: Dec 2002
Posts: 5,803
Default

I had it set to only 50%, so I increased it to 60%.

It looked like it was faster in opening, but by only a little. I don't know if its in my head or not. I'll have to do more testing later.

Eric
eric s is offline   Reply With Quote
Old Apr 22, 2004, 8:07 AM   #24
Senior Member
 
Join Date: Apr 2004
Posts: 192
Default Why colour balance during RAW conversion?

I've tried out the Capture One RAW conversion recently, and so far find it to be more or less equivalent to what Photoshop does. (And I don't mean Photoshop's RAW abilities -- I mean Photoshop's standard abilities applied after doing RAW conversion using the Canon utility.)

Perhaps there are technical advantages / reasons for doing this work in RAW conversion rather than in Photoshop, but I fail to (a) have technical knowledge / explanation (b) see the difference.

Can someone please elaborate / explain, ideally with examples?
Madwand is offline   Reply With Quote
Old Apr 22, 2004, 8:48 AM   #25
Senior Member
 
Join Date: Dec 2002
Posts: 5,803
Default

I can answer part of it. Changing white balance (I believe) changes each color channel a different amount. Doing that by hand would be difficult. You can do a crude form of white balance (at least I view it that way) but using levels and setting the white/grey/black point. That shifts each color channel independently to shift the point you selected to the color you specified.

For example, I took a picture of a American Kestral on a billboard. The billboard was supposed to be white on the side, but it was a grey mush. So I made it white using the white eyedroper in levels and it made the colors much better across the entire picture. You can see three pictures of that series here:
http://www.marx7.org/~esmith/menotom...le_kestrel.jpg
http://www.marx7.org/~esmith/menotom...le_kestrel.jpg
http://www.marx7.org/~esmith/menotom...ir/mating1.jpg

(the thing I white balanced on is not in the picture.) Notice how the sky is kinda muddy in the first and third picture, but is bluer in the 2nd one? It would have been easy with a good white balance control to make them all have a good blue sky (and therefor proper white balance.)

Changing exposure is like lightening the picture. I don't really know the difference between changing exposure and using levels or curves to lighten the picture. (Other than the fact that you can do the more than just lighten using those tools.) But it seems like using the exposure slider on the RAW does less damage to the picture than changing the brightness the other ways.

Eric
eric s is offline   Reply With Quote
 
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -5. The time now is 12:12 AM.