Olympus-OM
[Top] [All Lists]

[OM] Re: What are you using for HDR images?

Subject: [OM] Re: What are you using for HDR images?
From: Moose <olymoose@xxxxxxxxx>
Date: Fri, 05 Sep 2008 17:29:21 -0700
Chuck Norcutt wrote:
> The first two images here are HDR images of "my type". 
> <http://www.chucknorcutt.com/Barnstable_2008/>
>
> They're built from about 8 exposures 1 stop apart.  I think they're pretty 
> close to what I could see with my eye but the camera couldn't. 
I'm not entirely convinced - see below.
> On exposures where the sky showed a modest amount of color the foreground was 
> almost completely black.  When the foreground had some detail the sky was 
> completely blown.
>   
That sounds right.
> I like the way PhotoShop HDR works now that I understand it.  The resultant 
> 32 bit image has so much range that you can only view it in brightness 
> "slices" since there's no way for the monitor to reproduce it let alone a 
> print.
>   
I believe that too. The theory all sounds fine, but the results don't 
convince me, so far.

#1. On my monitor, there are areas of shadow where I can discern no 
detail. Pretty normal in a non HDR image, where bringing up shadow 
detail will often just bring up noise. Perfectly lovely image, but I'm 
not seeing much, if any, more DR than I imagine I would with a well 
exposed 5D RAW file.

Also, brightness seems to me to be the Achilles heel of monitor 
calibration. Color balance is fairly absolute, but brightness is not, so 
a brighter monitor will result in a different looking image than a 
darker one. In this case, if I raise brightness, there's lots of nice 
detail in the shadows, and with no noise issues, so the HDR worked in 
that sense. But if I do, highlight details disappear. So it seems to me 
that further adjustment is needed to take advantage of the greater 
available DR in a limited display environment.

I've done a couple of alternates where I spread shadows up a bit, 
highlights down a bit, add contrast to the center and use a mask to 
bring the tree trunks up a bit more. On my monitor, tree detail just 
almost completely disappears in the upper corners.There's more that 
could be revealed, but that doesn't seem natural looking to me. 
<http://www.moosemystic.net/Gallery/Others/CNorcutt/hdr-58-65_std.htm>

#2. This one bothers me more. Of course, it's possible that the air was 
really hazy, in which case, ignore my comments. It feels tonally 
ungrounded to me. The metaphor that pops to mind is a symphony where all 
the bass instruments are silent, with their parts played an octave 
higher by other instruments in the same family. There is also invisible, 
to me, sky detail, but it's the missing deep tones that bother me.

I invited the tympani, string basses, bassoons and tubas back to try 
some alternative versions. 
<http://www.moosemystic.net/Gallery/Others/CNorcutt/hdr_7052-57_std.htm>

#3. I know, it's not HDR. Still there it is to look at ... It seems to 
me to suffer to a lesser extent to the lack of grounding, gravitas, 
whatever I mean, as #2. Bring in the darker tones to balance the 
tonality and bring out the texture of the trunks, and it just sings for 
me. <http://www.moosemystic.net/Gallery/Others/CNorcutt/img_7146_std.htm>

No HDRs Yet Moose

==============================================
List usage info:     http://www.zuikoholic.com
List nannies:        olympusadmin@xxxxxxxxxx
==============================================

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