problem with IMCOMBINE + project=yes

Vallery Stanishev wrote on Feb 26, 2009

Hello,

I am using IMCOMBINE to project a 2D image along the columns. I have been using this on 1024x1024 images without problems for quite some time. Now I try to use the same on images with different size along the two axes and I get a strange errors:

ERROR: Out of space in image header (IMCMB728)

or

ERROR: Out of space in image header (ncombine)

I noticed that this usually happens (but not always) when the dimension along which I project is larger then 726. I extract the images from 1k x 1k images and imcopy keeps the CCDSEC keyword to [1:1024,1:1024], I initially had some success by deleting the CCDSEC keyword, but after a while the problem appeared again. It doesn't help even if I add CCDSEC keyword with the correct image dimensions. I also tried square images with different sizes, but again it doesn't work when the size is larger that 726-727.

Anyone could help?

/Vallery

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Mike Fitzpatrick wrote on Feb 26, 2009

The "out of space in image header" message typically means you have
exceeded the size of your "min_lenuserarea" environment variable.
You can increase this beyond the default value of 64000, in the cl:

cl> reset min_lenuserarea = 200000
cl> flpr

Alternatively, you can reset the min_lenuserarea in your login.cl
(or loginuser.cl) file and start a new IRAF session.

If you stil have problems, post back.

Cheers,
-Mike

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Francisco Valdes wrote on Feb 26, 2009

The basic cause is indeed trying to create a header with too many keywords. This seems to be because IMCOMBINE tries to document the data that went into the combination. There is a maximum number of IMCMB keywords it will try and create. I can't recall if it is in the current or next version of IMCOMBINE but there is an option to turn off or better control this record keeping. As a workaround, increasing the min_lenuserarea should solve the problem.

Yours,
Frank Valdes

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Last post on Feb 26, 2009