Non-contiguous profiles

KOZ · Post by **KOZ** » Tue Feb 18, 2003 12:59 am

Tried demo version this weekend and liked it. However, when constructing a noise profile, the sample area from the image being analyzed has to be in a contiguous square. It would be usefull if you could allow the noise profile to be constructed from several non-contiguous areas around the image, or at least do not constrain the profile to a square. Allow several squares, or rectangles, all of which would be analyzed as part of a single profile. It would make it easier to find an area in complex images to profile that way. In some images, I was not able to find a big enough area to construct a profile, so had to use the profile from another image taken at about the same time with the same camera. I suspect that's not as accurate as a profile taken from the actual image being filtered.

KOZ

Post by **NITeam** » Tue Feb 18, 2003 1:51 am

NI does need a rectangular area to be able to build a rough profile and several more rectangular areas to fine-tune this rough profile. The fact the areas should be rectangular is not big limitation, especially given there is always a possibility to build a profile using another image shot in the same or similar device more. It is not as bad (inaccurate) as you think. Please take a look at the recommended ways to build profiles: http://www.neatimage.com/profiling.html
Using another image produced in the same or similar conditions is one of the most desirable ways to build a profile, as you can see from that list.

Thank you for your suggestion and comments!

Best regards,
Vlad

mlougee · Post by **mlougee** » Wed Apr 30, 2003 2:25 pm

Would making a "test shot" be sensible, in which the test shot was composed mostly of the sky (if that were going to be the noisy area in the real shot), or a close-up of some object in the frame which might be noisy (the exterior of a car, which has some detail, but also has some medium-size areas without detail, and you'd take a close-up of those areas without detail. Then make the profile on the close up shot, but apply NI to the "real" shot? Maybe this "close up" strategy could be used on faces, too, for portrait shots?

Post by **NITeam** » Wed Apr 30, 2003 2:46 pm

Yes, this strategy can be used in most cases. Just make sure that the close up doesn't contain details when you use it for profiling.

Another possibility is taking an out-of-focus shot of something, which may have minor details that are then blurred by the out-of-focus lens.

sanaka · Post by **sanaka** » Thu Oct 23, 2003 9:31 am

I found NI through the review on Luminous Landscape. The suggestion there is to shoot the clear blue sky at all your different ISOs, and uild profiles from there. I did just that this mornig and am running batch mode on 100 or so pics with great results so far.

Post by **NITeam** » Thu Oct 23, 2003 9:36 am

Consider using the calibration target as well: http://www.neatimage.com/testtarget.html

Vlad