Use of the Despeckle filter in PS with Scans from Scan Dual IV

[sfb_dot_com]

Two other threads on scanning with the Scan Dual have been started today, and have provided for me much useful information to back up my own findings on this issue. Here is another potentially interesting or useful bit of information that might be of some use in the pursuit of less grainy images from this software/hardware combination.

The following observation arrived almost entirely by chance. I was examining one of my grainy images on PE Elements 3.0 when I applied the 'despeckle' filter (Filter>Noise>despeckle) I then applied the USM filter at 316% 0.6 0 which is a setting I often use on larger images (see the digital outback www.outbackphoto.com for an explanation on this) I found this to work just as expected, whereas previously applying USM had seemed to work disproportionately sharply compared to DSLR images. I then went through the same sequence, but omitted the despeckle, only to get a very different result. These are shown below. The despeckle itself does not seem to do very much by itself, but it sure makes a difference to USM.

I don't know what this means, but in practice if you are scanning on the SD IV and are getting grainy results using despeckle before USM might help keep it in check.

Results below..

Andy

 

[Justin Viiret]

I've find that a noise reduction filter like Noise Ninja works wonders, too, and it's a little more sophisticated/controllable than using despeckle or the dust and scratches filter. I usually profile based on the image, then back it off a couple of notches to avoid losing all the grain...

 

[Todd.Hanz]

I agree with using noise ninja but I also use the grain reduction filter in Vuescan, medium works pretty good. The DS IV seems to suffer from grain aliasing, some films worse than others.

"grain aliasing": http://www.photoscientia.co.uk/Grain.htm

Todd

 

[sfb_dot_com]

All good advice guys and something like noise Ninja is on the shopping list, sadly however due to lack of cash some way down the shopping list.

I'll see what the grain reduction filters do in the SD software, and my demo of Vuescan. I won't bother with Silverfast, it's just too clunky for my tastes.

Regards

Andy