RayTracer
07-30-2002, 02:55 PM
Hi, haven't visted these forums for awhile.
My wife has some taken some great photographs, if only the subject was in focus.
What are some great techniques for correcting out-of-focus images? Or where can I find some tutorials?
We have the negatives as well as 5x7 so we can scan either one (HP5470c Scanner with negative transparency light).
We want to submit these for a fair, but they have to be in by Friday (sorry for the short notice, we just got the proofs back today)
Thanks for any advice/help.
P.S. Love the challenges, need to try one of them soon. ;)
thomasgeorge
07-30-2002, 07:44 PM
The only way I know of to correct blurred/out of focus photos is via a software algorithm called Maximum Entropy Deconvolution or one of the other algorithmns such as Richardson-Lucy...these are used almost exclusively by astrophotographers and can yield some amazing results but the software which includes these routines is very spendy...at least $200.00 plus for proven packages...there is a program named Iris which is, I believe, freeware, but it assumes that you have a strong computer background and isnt what I would call exceptionally user friendly, but for those who know how to run it , it is reported to do a good job...Tom
In the short term it can be faked by adding noise, texture and some selective sharpening. It depends on how blurry the pictures are. Unfortunately, most blurred pictures can't be unblurred.
Mig
garfield
07-31-2002, 01:42 AM
where could I find iris the one that you said program is. What is its uses for?
Vikki
07-31-2002, 02:36 AM
Another technique I've seen, which gives the illusion of a sharper image, is to increase the blur in the background.
Stephen M
07-31-2002, 02:55 AM
This method is inspired by a technique mentioned by Katrin Eismann on the Sparky Photoshop List:
Dupe layer, set to overlay mode (where 50% gray is treated as transparent), run the emboss filter and match the light source to the emboss angle if possible, only emboss enough to restore some snap and do not push things too far.
It can get deeper than this...as my action illustrates in the post below.
Another method may be to run the crystalize filter and then apply an edge mask so that only selected extreme edges have the filtering.
Attached is a JPG example of the Unblur action in use.
Regards,
Stephen.
Stephen M
07-31-2002, 02:57 AM
Here is the Unblur action for v5.x or higher (also posted in the 'goodies' section for actions etc).
Stephen Marsh.
Jakaleena
07-31-2002, 05:59 PM
There's a tutorial HERE (http://www.retouchpro.com/tutorials/looksharp/index.html) on giving a sharper appearance to fuzzy photos.
thomasgeorge
07-31-2002, 08:21 PM
Try a general search with the key word IRIS...it is specalized Digital Astrophotographical processing software, but it may have some use in correcting blurred images as the Algorithms previously referred to were developed to correct just such problems. Another program, Maxim DL, which is a powerful but rather expensive Astrophoto image processing program also has the Max Ent routine...Tom