Re: A first look at DS24

[Arne Henden <aah@nofs.navy.mil>]

I always prefer a 0-65535 representation since that is the way
most professional and amateur cameras use their ADCs, instead
of the TASS two's complement.  Changing BZERO is a simple trick
so that you don't have to add 32768 in some subsequent processing.
Just be careful about the datatype into which you read the images.
Of course, Tom will have to quit describing data negatively...
Arne

Robert Creager wrote:
> Tom Droege <tdroege2@earthlink.net> wrote ..
> 
>>>        Can we get a BZERO = 32768. added to the FITS headers?  It would
>>>make life much easier
>>>when using CFITSIO.
>>
> 
> I vote for this!  I've done just that on the download program I'm currently using (downfits child).  I can re-release downfits with this in place if desired.  The current release of downfits won't allow you (Tom) to specify BZERO within the constant or plate files, so that won't work.
> 
> Ted, in the mean time, what I've done in my CFITSIO programs which work on TOM images, I add the following right after I open the image:
> 
> int type;
> fits_get_img_type( ftpr, &type, &status );
> if ( type == SHORT_IMG )
>    {
>    fits_set_bscale( ftpr, 1, 32768, &status );
>    }
> 
> Cheers,
> Rob
> 
> 
> 
>