Olympus-OM
[Top] [All Lists]

Re: [OM] Struggling with light at Ballenberg in 2009

Subject: Re: [OM] Struggling with light at Ballenberg in 2009
From: Moose <olymoose@xxxxxxxxx>
Date: Thu, 23 Apr 2009 22:30:23 -0700
Ken Norton wrote:
> What I'm seeing in the pictures, which is a little disconcerting to me 
> personally, is too much shadow recovery. That's what I was implying by my 
> comment about an S-curve adjustment to fatten up the bottom end. What 
> highlight and shadow recovery do is bump UP the shadows and pull DOWN the 
> highlights. All fine and dandy, but you can end up with flat and 
> linear-looking images.
>   

I quite agree. However, I don't think the problem is one of tools, so 
much as of user technique. Both in true HDR and in ordinary images that 
have been treated to recover highlight and/or shadow detail, it's very 
common to see a flat look for just the reason you give. It is not, 
however, inevitable. 
<http://www.moosemystic.net/Gallery/Others/Swiss/Ballenberg1.htm>
- <http://www.moosemystic.net/Gallery/Others/Swiss/Ballenberg2.htm>

> The big difference between a film image and digital image in a high-contrast 
> situation like this, is that film has a shoulder and toe which maintains 
> details, yet the dynamic range within the shoulder and toe is highly 
> compressed. 

Here I slightly disagree. Although digital sensors are linear, the JPEG 
output of digital cameras and of RAW converters have shoulders and toes. 
They generally aren't as long as film, and may or may not be good for 
any particular subject, but they are very much there. Here are the 
curves for the E-3. <http://www.dpreview.com/reviews/olympuse3/page21.asp>

> HDR, or highly recovered shadows and highlights will take what is normally 
> part of the upper and lower reaches of the dynamic range--those areas where 
> the eye will accept compression and stretches them out while compressing the 
> mid-tones. What you end up with, and this is quite apparent in these images, 
> is the midtone contrast not following a typical, say, 2:1 contrast ratio, but 
> more like a 4:1 contrast ratio.  It creates a rather flat image, which may 
> show all the dynamic range, but the midtones are uncomfortably squished.
>   

Yup (although do you have the ratios reversed?) The thing is, it's easy 
enough to change the amount and shape of the compression curves, at what 
values they start and the slope of the midtone curve.The designers of 
the Shadow/Highlight tool in PS were obviously aware of this problem, as 
they included a Midtone Contrast slider. It's not a complete solution, 
but quite effective in many images.

The second cause of trouble is that many such images have not had proper 
sharpening and/or LCE applied. ANY digitally captured image has soft 
local edge contrast; it's an inevitable part of the process. As both you 
and I have pointed out more than once, our visual systems are VERY 
sensitive to edge contrast. Anything with soft edges will tend to look 
washed out or veiled.

Moose
-- 
_________________________________________________________________
Options: http://lists.thomasclausen.net/mailman/listinfo/olympus
Archives: http://lists.thomasclausen.net/mailman/private/olympus/
Themed Olympus Photo Exhibition: http://www.tope.nl/

<Prev in Thread] Current Thread [Next in Thread>
Sponsored by Tako
Impressum | Datenschutz