[Radiance-general] about wxfalsecolor problem

[Greg Ward]

I am not familiar with wxfalsecolor.  Is it possible that it is not taking into account the EXPOSURE setting in the header?  What happens when you use the -1 option to pfilt?

-Greg

> From: Thomas Bleicher <tbleicher at googlemail.com>
> Date: December 12, 2010 9:15:05 PM PST
> 
> Hallo.
> 
> wxfalsecolor does not calculate values for luminance or illuminance.
> Instead it uses the Radiance tool pvalue to extract this information
> from the image. I am surprised that pvalue and Photosphere come up
> with different values, though. Greg is probably the best to comment
> on this. I myself have never used Photosphere.
> 
> The size related popup is just gives you the option to skip the pvalue
> step when the image is loaded. It can take a while (especially for large
> image) and for most of the features it is not necessary.
> 
> Regards,
> Thomas
> 
> 
> On Sun, Dec 12, 2010 at 11:36 PM, Mehmedalp Tural <mtural at asu.edu> wrote:
>> Hello Mr. Bleicher,
>> 
>> I am a PhD student at Arizona State University. I learned about the
>> wxfalsecolor and falsecolor2 from Radiance mailing list.
>> I have a question regarding the computed luminance values. I created my hdrs
>> using Photosphere and run pfilt to reduce their resolution (to run evalglare
>> faster).
>> I checked the average luminance of a selected region before and after
>> running pfilt and the results were identical under Photosphere.
>> However, wxfalsecolor computed the average luminance of the same region two
>> times more than Photosphere.
>> (I did not process the hdr file using any other software like Photoshop,
>> knowing that even cropping would change pixel values).
>> What could be the reason for this difference? Wxfalsecolor pops-up an
>> attention window for large file sizes. Is there a file size limit?
>> I'd appreciate your comments.
>> 
>> Sincerely,
>> 
>> Mehmedalp Tural
>> PhD Candidate
>> Herberger Institute
>> Arizona State U