Quote:
Originally Posted by Gidders
Roy - Chris is right to question this because this is definitely NOT the case. ANY edit in PS modifies pixel values and therefore destroys information. I appreciate that if you work with layers that is not destructive editing and you can return to the original, but when you flatten the image for web or print it you are then taking the modified values. In contrast editing in RAW does not. You should do as much editing in RAW as possible and then switch to PS for edits that can not be carried out in your RAW processor eg selective edits, althhough I believe that LR in V2 now has some selective processing capability.
By way of an example here are three version of an image that I took the lake district a few weeks ago. This is deliberately underexposed as part of a bracketed series but it serves to show the difference between processing in RAW and PS. Obviously with correctly exposed images, the effects are less exederated, but will still be there.
Image 1 is the as shot RAW converted to 16bit with no adjustments and then resized and converted to JPG
Image 2 is the above image with a curves adjustment added in PS.
Image 3 is the RAW image with exposure, fill light & black level adjustments in LR and then converted to 16bit and the resized and converted to JPG.
In each case I have superimposed the histogram in the corner. Note in images 1 & 3 the histogram is continuous, were as in image 2 there are large gaps - denoting the complete absence of pixels with that value, the net result being loss of tonal range & shadow detail in particular, which is visible in the shadows on the hills.
To lean how to get to grips with the LR/PS RAW converter interface try either of these books: -
Real World Camera RAW by Bruce Fraser
Photoshop Lightroom by Martin Evening
Its worth the effort  |
I did not intend for this post to get into one of those never ending arguments about processing and Nikon v Canon. If you see my original post I was just commenting on the amount of detail that a telephoto lens can capture.
I appreciate that the final image is probable very poor in most peoples mind and that Canon folk can never reach the dizzy heights of the Nikon shooters but the thread was never about quality of shot or how you process an image.
When Chris was talking about 16 bit Tiffs retaining the info I thought he was thinking about when you actually take the image into PS not after/during editing besides which by the time you have converted to jpeg for the web (which was what this thread was all about) you are ditching loads of info anyway.
I did not say I did not know how to use LR as most of it is similar to the ACR that I used for several years before I got the 40D. What I do not like about it is the user interface, in fact I hate it
23-08-08, 15:29
