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[OM] Re: Hajstorp, southwestern Sweden, last summer

Subject: [OM] Re: Hajstorp, southwestern Sweden, last summer
From: Moose <olymoose@xxxxxxxxxxxxxxx>
Date: Thu, 02 Mar 2006 16:51:02 -0800
Jonas Otter wrote:

>If you have any suggestions as to what adjustments are needed and how much of 
>them, or a pointer to a tutorial or something, I would be eternally grateful 
>:-)
>  
>
Well, often happy to oblige.  :-) 

It certainly is possible to color manage many laptop LCDs for good image 
editing performance. In my case, the color management settings are far from 
what I want for everyday edit, email, etc. activities, so I have to go back and 
forth, not a big deal. In any case, if you prefer my mouse over adj. you may 
not be too terribly far off.

I can't help with the GIMP, as I don't use it. I do my image editing in PS, 
CS/8 for the moment, but it doesn't matter which version for this. I've made a 
little step by step example of what I did to your image 
<http://www.moosemystic.net/Gallery/tech/Tut01bw.htm>.

The steps are:
1. The full image from the scanner, downsized.

2. The same image, smaller, and its histogram. Note how so much of the tonal 
info is clustered down at the bottom. That can happen naturally with some 
images, but is clearly wrong for this natural scene with a full range of 
different tones in the subject. Note on the histogram the position of the 
black, white and center point sliders and the numeric settings at the top.

3. This is the result, image and histogram, of the above settings for the 
Levels command. Much more balanced, not so dark, but still pretty dull looking.

4. This shows the Unsharp Mask settings for Local Contrast Enhancement that I 
used in PS and the result. This is not sharpening in the conventional sense. 
With such a large radius setting, it does something I don't fully understand in 
a technical way. What I do know is that this sort of use of unsharp mask 
enhances contrast locally, rather than globally, and often has the effect of 
"lifting a veil" from over the image.

5. This shows the settings of the Curves command that I used and their result. 
This adds contrast in the middle tonal area and compresses tonal graduation in 
the highest ans lowest ranges. For reasons I don't understand, this control 
works the opposite in color and gray scale in PS, so the slight downward adjust 
of the center point actually lightens the image central tones. In another 
editor, this direction might be the opposite.

6. The histogram here shows the result of the last two actions. The little 
hillock near the top of the last histogram has been pushed partially off the 
end, resulting in loss of lots of highlight detail. This is ok (and I knew it 
was happening), because I noted early on an odd characteristic of this image, 
one part looks like it was exposed differently than the rest. Not so, of 
course, but it looks that way. So I selected that area and copied it to a 
separate layer, unaffected by the above adjustments. I then separately adjusted 
it. The layer as adjusted is shown here. The adjustments have made it quite a 
bit darker, but have not blown the highlights.

7. This shows the above layer combined with the rest of the image and resulting 
histogram. See how the hillock has moved back down and blended in with the rest 
of the histogram. There are small lines at the top and bottom, representing 
slight loss of tonal detail at the very top and bottom. I could have avoided 
this, but black and white points slightly les than the full range are pretty 
normal and they fit the result I wanted. Notice that the new layer is slightly 
lighter than above. I adjusted its opacity to lighten its effect a bit. I chose 
to bring it to tonal balance with adjacent areas, eliminating the differential 
brightness. One could also lighten it separately to retain the differential 
brightness effect of the original to whatever degree one wishs.

8. The adjusted image, sharpened slightly in downsizing. 

The degree to which one may wish to do any of theses steps is, of course, a 
matter of personal artistic taste, but this general set of actions is a useful 
way to approach any image with wonky tonal distribution. flat contrast, veiled 
detail, etc. I would sometimes use a different order of actions. 

The really important things are to stay in 16 bit and not to allow highlight or 
shadow detail to be lost unintentionally. This will not uncommonly require 
contrast and/or brightness adjustments before Curves and especially LCE 
adjustments to allow room at the ends for their effects. Sometimes this will 
require going back a step, adjusting brightness/contrast, then going forward 
again. I always do these adjustments in separate layers at first, so I can turn 
the changes on and off while looking at their effects on different parts of the 
image and on the histogram. Often if the result is close, but a little 
overdone, adjustment of the layer opacity provides an easier way to make subtle 
adjustments than going back and forth making adjustments to the command 
parameters.

Hope this is of assistance.

Moose

Jonas Otter wrote:

>>Although it gives a very soft, nostalgic look, the tonality seems odd to 
>>me, no pure blacks or whites to speak of and very low contrast. It's 
>>sort of like a veil over the picture. I have no idea whether this is 
>>intentional nor whether it is a result of film, processing, scanning, etc.
>>
>>In any case, I couldn't resist trying a couple of other "looks" at it 
>><http://moosemystic.net/Gallery/Others/Sum05.htm>.
>>    
>>
>Thanks for looking and for the suggestions. The strange effect is definitely 
>user error. I have been trying to fix up the pictures on my laptop using the 
>Gimp and sadly the screen is useless for pictures. I am not used to using 
>these picture editor thingies either, I know how to do it the old-fashioned 
>way with enlargers and stuff. 
>
>I preferred your mouse-over version, which was much better than my effort. I 
>redid my picture trying to get more contrast, however it may have turned out 
>rather dark. I also posted the original TIFF (14 MB) from the scanner, 
>http://jonas.otter.se/pictures/summer_2005/img031.tif 
>
>If you have any suggestions as to what adjustments are needed and how much of 
>them, or a pointer to a tutorial or something, I would be eternally grateful 
>:-)
>
>I shall definitely make paper enlargements of these photos as they seem to 
>have turned out very well if one takes into account how I have munged them on 
>the computer :-)
>



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