Lama made suggestions re this posting
>
> From: "Bachofen"
> Howdy all,
> I thought I'd post some of that wacky flare from my 85mm f2,0 while mounted on
> my OM2n.
> http://pwp.clearsource.net/mbachofen/images/photographs/85mmflare2.jpg
I've had a look at these, and there are some clues right there.
1) The flares are always on the top-side of the camera/lens combo.
2) They are also always on the same side of the lens regardless of distance
to subject (couldn't really see very well in the horse shot)
3) The pattern of the little constituent parts of the flares in every photo is
almost identical. The size is always about the same. The shape is always
about the same. Minor changes maybe due to the alteration of focus.
4). The colour of the flares is always the same - white light.
5). The lens was wearing a rubber lens-hood when the photos were shot so
that rules out flare from the front rim.
I don't have an 85/2 lens and have no way to borrow one to examine, so I
can't say if any part of the glass or the barrel internals which hold the glass
rotates as focus alters.
Matt says it is just this lens that gives these artifacts, so that rules out
problems with CAMERA bodies.
So all the above point to something inside the lens which is reflecting white
light. Situated either on the (mounted) topside of the lens, or exactly
opposite it. Not to one side or the other. And not in print processing.
If it were my lens, now I would be looking through it with a black background
and a bare light-bulb fairly close. I'd be holding the lens at an angle to the
light so that just a small shaft of light from the bulb came through the lens,
and I'd be looking for
reflective metal in the barrel cavity. Black paint missing.
reflections from the mount or the edge of one or more lens elements.
a significant piece (or close group pieces) of hair or dust on one lens
element, close to the edge.
I would expect to have to fiddle around with the path of the light to get the
defects to show up. It could take some time. The defects are probably not
large, but I'd expect them to be bright if a bare bulb held close is used.
Look from each end (not at the same time ) <g>.
My 2c worth.
Brian
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