[HDR-photo] Follow up to Breeze DSLR Remote and PX...

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On Mar 2, 2008, at 9:14 AM, Jack Howard wrote:

>
> OK, i've discovered that the command line is "photomatix.bat"
>
> and if you Connected Canon Camera is in RAW-only mode, Remote Pro  
> will blast your mega AEB sequence and run command line codes and  
> save both a Radiance file and a Tone Compressed JPEG. However, my  
> experimental shots were shot with AWB under Tungstens and had  
> slightly warm cast to them--but the output files were skewed very  
> much purple--not magenta, per se, but purple--like dyed easter egg  
> purple.
>
> Anyone else have any experience with this software combo and have  
> any good advices for optimizing a workflow?

Hi Jack,

Back when I used Canon (not so long ago), I would shoot JPEG with  
DSLR Remote Pro because the provided script had no way of telling  
Photomatix what WB to use and because my camera was old and slow  
enough that transferring RAWs to the laptop meant the camera was  
waiting on file transfer - not shutter speed. I compensated by  
shooting 1 stop apart instead of my usual RAW 2 stops, and the  
results were good but sometimes artifacts made them less-than- 
spectacular (exaggerated purple fringies, vignetting, etc.) without  
my typical ACR workflow.

Check if there is an entry in .bat for setting the WB in Photomatix.  
Also, using Auto WB is risky for HDR (either in Photomatix or in  
camera if you choose "as shot") - as it can actually vary between  
exposures even when framing the same subject, to say nothing of  
shooting panoramas where the framing can change. Consistency is the  
key to good HDRs right out of Photomatix-  even from RAW files with a  
bit more latitude. Some folks even use dcraw's "linear" output to  
guarantee minimal variance in shots, but I think that's going a bit  
far... like I said, I get good results from JPEGs when the WB is  
properly set with a card and the sharpening and compression are minimal.

As for the purple HDRs - you'd be surprised what you can do with  
Photoshop and the Photo Filters if it isn't too bad. Don't think of a  
32-bit file's colors like an 8 or 16-bit file's "permanent" colors -  
you can shift them radically in 32-bit and not destroy too much of  
the *overall* information. Christian Bloch recommended nearly  
desaturating (with H&S at -90) an HDR and saving and closing it, then  
reopening it and "boosting" the saturation back up (H&S +90) from  
what appears to be grayscale - and yes, the colors come back! (not  
quite what was there before, but reassuring nontheless). I was pretty  
floored by this when I tried it...

-Mark