Unsharp Mask

[Robby]

Steve,
I think robin is trying the real unshape mask as mentioned right at the top of the thread...

Originally posted by iceman
You can try this page by Jerry L, astrophotography guru..
http://www.astropix.com/HTML/J_DIGIT/USM.HTM
I haven't tried that technique myself, but it looks good!

Robin,
What program are you using? I used Photoshop, and didn't exactly follow the instructions to the letter. Where the method talks about "apply image", I just used layer subtract. Essentially the same thing, just easier. Try resetting the white point in levels if the final image is too dim, and then stretch the levels some more to acheive a balanced result. Also reducing the brightness of the mask will increase output brightness, but you will have less unshape mask.
Hope this helps
Cheers
Rob

[robin]

I'm doing it the same as the instructions in the link say to.It sharpens the image nicely but always appears much darker,ie: a LOT darker, than the original image. My images are 96 dpi, i take the contrast/brightness to -30 as it says to do. Maybe -30 is too much?


http://www.astropix.com/HTML/J_DIGIT/USM.HTM

[robin]

By the ways guys, I'm using Adobe P.Shop 6. I'm not new to photoshop, been using it 10 years now but I am new to this method of applying an unsharp mask. I'm following the instructions as opposed to going to filters/sharpen/unsharp-mask. Like I said, it sharpens the image REAL nice, but makes it much darker.I'm sure it's only something minor I'm not doing right.