wwp@yahoogroups.com:
Re: Nikon 2.8/10,5 Sigma 3.5/8 or Tokina 10-17 ?
Hans Nyberg 2009-May-11 00:54:00
On 11/05/2009, at 2.00, Alex Makienko wrote:
> C'mon! Do you think I'm a rookie? ;-) Please be sure that having 30
> + years in serious photography (including professionsl one) and
> being MS in physics (you probably know that optics is the part of
> physics) I know how to keep lens clean.
>
> For your information: Flares shaped like spots, polygons and
> somethong like that are NEVER caused by grease, fingerprints,
> scratches etc. These defects cause parasitic beams, star-like
> spots, additional lighting and anything else BUT spots and flares.
> I hope I do not need to refer to a fundamental optics to confirm
> that. Please just trust my experience in physics (and optics
> particulary) and photography.
Sorry Alex but I beat you. I have 56 years experience in photography
of which 42 is as a professional photographer,
Of course you get flares with poligons because of a lens which is
not cleaned.
Here is an example taken a couple of years ago.
http://www.panoramas.dk/panorama/flare/dust.jpg
This is the Canon 15mm one the best fisheye you can get. It has
practically no flare very little CA very little lightfall and
sharpness is exellent.
However I took my brand new lens and went out to test it without even
taking the lens cap of and look at the frontlens.
I did not think of that it had to be cleaned before I used it, and
on top of that I also by mistake on my new 5D stopped down to F19
which accelerated the problem.
I see this a lot on panos made even by very experienced
photographers. And people complain that the lens has flares but in
reality it is just a dirty lens stopped down to 16 or even 22.
Hans
Hans Nyberg
Panoramas.dk<http://www.panoramas.dk>
Features Fullscreen Panoramas from the best VR Photographers in the
World
email: #removed#
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