View on GitHub

IRAF Community Distribution

IRAF maintained by the community

Home | Installation | Packages | X11IRAF | PyRAF | Forum

MSCDISPLAY produce imaginary noise

johannes1808 wrote on Dec 11, 2009

HI

I have some problems with the mscred task mscdisplay. When I am looking at my data with mscdisplay and ds9 many noise were produced, this noise does not occur when using display and furthermore the initial data does not have that thing. Im using IRAF Revision 2.14.1 with mscred 2.0. Thanks a lot for your help.

Mike Fitzpatrick wrote on Dec 11, 2009

Without seeing a sample image, it's hard to say whether this is a real problem or something easily explained: MSCRED is currently at v4.9 so if indeed you have v2.0 you might try the latest version to rule out any problems in the software.

What you may be seeing is a difference in the scaling used by MSCDISPLAY (and DISPLAY) and that done when you load an image in DS9 directly. If you load from DS9 and use the 'ZScale" scaling algorith do you see the same artifacts? Another explanation might be
aliasing effects in the display, i.e. artifacts introduced by scaling the pixels in the frame buffer to the (usually smaller) window on the monitor. Do you set a 'stdimage' large enough for the image or do you set the 'fill' parameter to scale the image to a smaller frame buffer? Could you possibly post an image so we can see what you're talking about?

-Mike

johannes1808 wrote on Dec 11, 2009

Hi,

the error was just a too slow value for stdimage, anyway its interesting that binning causts such effects. Thanks a lot for your help. :D

Last post on Dec 11, 2009