I'll have to fall back on a single argument: It's only a single lens
surface. From http://www.photodo.com/art/Anti12.shtml
"As the number of elements increases (for example 1, 2, 3, 4, 5, and 6)
you get an increase in element reflection (1, 6, 15, 28, 45, and 66
reflections respectively)"
So coating loss on 1/10 of the front element of a 6-element lens would
only contribute 1/10 x 1/66 of the total glare, or 1/660, times the
increase in reflection, perhaps 8:1, so 1/82nd of total glare, or a
very minor loss of contrast in the resulting picture. The proportion
would be greater for a 4-element Tessar, less for a 16-element zoom.
So some front coating loss won't ruin a lens, just add a little flare.
There's a reason for those lens shades!
And I do wear glasses -- coated ones...
tOM
On Wednesday, September 11, 2002 at 11:58, C.H.Ling
<olympus@xxxxxxxxxxxxxxx>
wrote re "Re: [OM] Fang! possibly two" saying:
> I bet you don't wear glasses, in the old days when coated glasses is
> still not so common, at backlight situation you will see the light
> reflected on the front of the glasses with your eye behind. Reflection
> on one surface will be seen from the other side. No one will put
> coating on the front lens if just for good looking, coat a lens is
> costly.
>
> Still not believe?
>
> check the following from photodo:
>
> "There were not only strong reflections between the different
> elements, but also between the two surfaces of any single element."
>
> the link is:
>
> http://www.photodo.com/art/Anti12.shtml
>
> some more...:
>
> http://www.nikon.co.jp/main/eng/society/tec-rep/plastic_lens.htm
>
>
> C.H.Ling
>
> Tom Trottier wrote:
> >
> > 1/20 of a stop, and that assumes that all the coating is lost.
> >
> > tOM
> >
> > On Tuesday, September 10, 2002 at 16:17, C.H.Ling
> > <olympus@xxxxxxxxxxxxxxx>
> > wrote re "Re: [OM] Fang! possibly two" saying:
> >
> > > Not only a little, a single non coated surface reflect up to 50f
> > > light.
> > >
> > > C.H.Ling
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