Olympus-OM
[Top] [All Lists]

Re: [OM] Re: olympus-digest V2 #1820

Subject: Re: [OM] Re: olympus-digest V2 #1820
From: "Lex Jenkins" <lexjenkins@xxxxxxxxxxx>
Date: Sat, 02 Sep 2000 22:38:03 GMT
I predict a long thread arguing the finest points of UV transmission, optics and filters. Oh, yes, and loss of resolution when using filters.

Or not.  #^)

Lex (donning panic-proof sunglasses)
====================================


Dear David and fellow Zuiks --

I think this is a case of Ultraviolet sensitivity of color film and
I would guess that you did not use any type of UV absorbing filter
over the Zuiko 180 mm lens.
Ultraviolet can cause just the sort of effects that that you showed with
those nice images of the brunette in the white top and khaki skirt.
I don't think this is a case of chromatic abberation -- the focus of different
wavelengths at different plane.
Single coated lenses transmit more ultraviolet light than multicoated lenses. Most of the time ultraviolet does not cause a problem but on bright sunny days
or other bright illumiation ultraviolet effects show up.
If you can find a Wratten 1A or 2C filter gel and a holder for your lens then you'll have a good solution. Filter gels are thinner and optically better than glass filters, so you'll probably be happier with the results if you can find a suitable gel holder. I use both an old Kodak metal holder and a Cokin filter holder with a 3X3 gel holder on my 49 and 55 mm Zuikos but I don't know if this will work
for the big 180mm -- what is the filter size ?

For ultraviolet photography, of course gels won't work so I use a B&W glass
filter containing Schott UG1 glass. http://flzhgn.home.mindspring.com/uv.htm
When I want to remove all UV light I use a Wratten 12 yellow filter.

Now I want to know more about the Vivitar 17mm lens because I just bought one ! I am thinking of getting a UV0 glass filter for protecting the front element maybe I should
consider a Wratten 2C or even a 2E !

I think Kodak films are generally less sensitive to ultraviolet effects than Fuji films except for Kodak EIR and Fujichrome 64 T which are both wonderful for photographing
true ultraviolet images.

-- Hank Hogan <hogant@xxxxxxxxxxxxxx>
    http://flzhgn.home.mindspring.com/indexc.htm


_________________________________________________________________________
Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com.

Share information about yourself, create your own public profile at http://profiles.msn.com.


< This message was delivered via the Olympus Mailing List >
< For questions, mailto:owner-olympus@xxxxxxxxxxxxxxx >
< Web Page: http://Zuiko.sls.bc.ca/swright/olympuslist.html >


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