View single post by Eric
 Posted: Sat Jun 6th, 2015 05:53
Eric



Joined: Thu Apr 19th, 2012
Location: United Kingdom
Posts: 4424
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jk wrote:
It is the Fuji 14mm f2.8 which ismeant to be good in IR as well as normal light.
I noticed this in other images as well maybe at 665nm the lens is not so good!
It is very good in normal light.


I use the cheap 16-55 Fuji, which for some reason is nowhere near as bad as the more expensive zooms. Nevertheless less there is a slight central lighter area which sometimes I need to adjust. Stopping down increases hotspotting, as does wider angles. So I keep to f5.6 and avoid the 16-18mm end of the zoom as much as possible.

I haven't got any Fuji primes. But I did a quick check at WEX and they seemed to be free from hotspotting. Certainly they didn't seem to be any worse than the 16-55, but it was only a quick test in the showroom ...and at £120 for a used zoom I could not resist grabbing it. Lol

It may be worth doing a range of f-stops on same image to see if it is aperture sensitive.

I think vignettes and hotspotting always look more obvious on limited palette images. Something that should be white, tapering to dirty dark grey at the edges, is a lot less attractive and therefore noticeable.

It's not the end of the world, just an extra process step to counter it.

In fairness...I used PS for iPad presets to get that last image. There may have been something in the algorithm that ADDED some vignette to it....so don't despair.

But even in your original image the cables on the bridge get darker towards the right edge.

;-)

Last edited on Sat Jun 6th, 2015 06:25 by Eric



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Eric