Olympus-OM
[Top] [All Lists]

[OM] Re: Superwide lenses - advice

Subject: [OM] Re: Superwide lenses - advice
From: Moose <olymoose@xxxxxxxxx>
Date: Sun, 01 Apr 2007 00:48:53 -0700
Andrew Fildes wrote:
> ............
> No one mentioned vignetting I think - it can be a problem - I like to  
> think of the edges of the frame as being stretched out to form a  
> rectilinear image and so there's distortion and the light gets  
> 'thinner'.
>   
Take a look at the two images with vignetting corrected in the page I 
just posted about perspective. 
http://www.moosemystic.net/Gallery/tech/Lenses/Perspective/Perspective/

The vignetting correction is simply by eye with a couple of sliders, so 
it may be used with images from any source.
> There are some programs which will correct for distortion as i  
> remember - they were discussed on Luminous Landscape - but they have  
> algorithms for each lens so there may not be a 'repair' available for  
> heritage lenses. 
PTLens also has a database of DSLRs and lenses that will correct linear 
distortion. Works very well. Faced with a lens not in the database, one 
may take test image(s) and send them in for analysis and addition to the 
database. He doesn't do old film SLRs, but I notice entries for the 
Schneider 28 mm PC lens and Hartblei 35/2.8 PC lenses.

Considering the number of Zuiko super-wides being used on FF Canyon 
bodies, I suspect he would add those if asked and given sample images 
meeting his specs.

Absent that, one may use an image from a MF lens with clear lines in it 
and simply browse through the wide angle lenses to find one that does a 
good job, then note it for future use.
> They seem to do a great job on straightening something like a Canon 16mm 
> fisheye from what I've seen.
>   
Fisheye correction in PTLens is outside the database and done manually 
with sliders.

At $15, PTLens is a steal.

Moose

==============================================
List usage info:     http://www.zuikoholic.com
List nannies:        olympusadmin@xxxxxxxxxx
==============================================

<Prev in Thread] Current Thread [Next in Thread>
Sponsored by Tako
Impressum | Datenschutz