i just downloaded and tried out a new Photoshop plugin called FocusFixer. it does exactly what it says, it fixes out-of-focus images provided they are not too far out of focus. the documentation doesn't say much about how it does it, but from the image processing courses i have taken and experimenting with the sliders, it does a deconvolution of the image. this is the proper mathematical technique for fixing focusing errors and other lens abberrations by digital processing of the image and recovering the perfectly focused image. it works perfectly if you know the abberations perfectly. in the case of pure misfocusing, you know it pretty closely even if you didn't measure the lens to recover the deconvolution kernel. this assumes that there aren't many abberations in the lens.
i tried it on a couple of 4000dpi scanned images where i thought the camera was in AF mode when it was actually in MF mode focused relatively near but i was shooting at f22. that meant that the entire image was slighly out of focus. with only a little work on the sliders, i was able to bring the entire image basically into focus. i tried a rezed up digital image file, doubling the resolution using bicubic interpolation in Photoshop and then applying the filter. it made the image much sharper than before, almost as if i had 4X as many pixels to start with, certainly about as effective as 2X. i also used it on scanned images that were perfectly in focus but from a "lesser" quality lens. it is just a soft lens without any appreciable chromatic abberation. that image improved in sharpness quite a bit. the sharpness is real sharpness and not the kind that a regular sharpen filter in Photoshop does. it corrects for lens defocusing, which is not the same thing. there are drawbacks though. it is a CPU and memory hog. it is slow on a Pentium 4 1.8GHz machine. if you adjust too much, it makes the image look really bizarre. any film grain in the image gets emphasized, but not as much as a pure sharpen filter does. there is another commercial Photoshop filter that does the same thing, but you can only buy it as part of a package for $799. this plugin sells for $49 and runs in demo mode with no watermarks or anything like that for 20 uses. after that, you have to register it. you need about 3 images to convince yourself it works. if you are in the habit of applying an unsharp mask to your images in their final stage, this is a higher quality alternative but it takes more time and shouldn't be automated because you need to tune its parameters for each image. i bought mine after trying it on 3 images. http://www.fixerlabs.com Herb....
