Olympus-OM
[Top] [All Lists]

Re: [OM] Fang! possibly two

Subject: Re: [OM] Fang! possibly two
From: Tom@xxxxxxxxxxxxx
Date: Tue, 10 Sep 2002 20:07:05 -0400
On Tuesday, September 10, 2002 at 14:09, Chris Barrett 
<olympus@xxxxxxxxxxxxxxx>
wrote re "[OM] Fang! possibly two" saying:

> Tom wrote:
> 
> "Why?
> 
> It matters the least on the front of the lens. 
> It increases transparency by a little, but doesn't reduce glare at all, 
> unless you have a filter on."
> 
> Sorry Tom,  I have to agree with C.H.
> 
> The antireflection coating on the front surface works both ways. It
> reduces reflections from the front and therefore increases transmission
> as you say. 
> 
> But it also reduces reflection of light bounced back from within the
> lens. In order to reduce flare light, all surfaces need to be as low
> reflectivity as possible. 

How does the *front* coating of the front lens reduce "reflection of light 
bounced back from within the lens"?  (except by reducing the amount of 
light going in, which a lens cap does even better).

Are you saying it reduces reflections inside of the front lens element by 
the light going forward through the lens and hitting the front surface of 
the lens? Is there any such reflection inside the glass? I thought 
reflections only occurred from when light came from the low refractivity 
medium, unless the angle were too sharp, when there would be 100% 
reflection, like a prism.

tOM--
--------- http://groups.yahoo.com/group/Olympus-Documentation
--------- http://groups.yahoo.com/group/ottawa-photo-clubs
tOM Trottier,   ICQ:57647974    http://abacurial.com
        758 Albert St, Ottawa ON Canada K1R 7V8 
        +1 613 860-6633 fax:231-6115 N45.412 W75.714
"The moment one gives close attention to anything, 
even a blade of grass, it becomes a mysterious, 
awesome, indescribably magnificent world in itself -- 
Henry Miller, 1891-1980


< 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