re stopping down, I think it does mean that less of the rear element is used. Just tested it with a lens that has a bit of dust on it (so I could see where the light went).
David
>> stopping way down just makes it a larger >> percentage of lens surface in use. > > Are you sure that's the case for the rear element? > > S
J. C. O'Connell wrote:
Just touch it with the tip of a black permanent marker
then lightly wipe with a alcohol moistened tissue not
pressing hard enuff to remove the ink from in the scratch.
try on a junk lens first (scratch it if you have to)
to get the hang of it. I did this on a big LF lens that
had several nicks and the lens worked fine with the blacked out nicks. The middle of the lens is no worse
than anywhere else except that stopping down does not
eliminate it and stopping way down just makes it a larger
percentage of lens surface in use.
JCO
-----Original Message-----
From: David Nelson [mailto:[EMAIL PROTECTED] Sent: Wednesday, July 28, 2004 12:57 AM
To: [EMAIL PROTECTED]
Subject: Scratch on rear element
G'day folks, I recently got an A* 300/4 for a great price in 'bargain' condition, due
to a miniscule nick in the centre of the rear element.
As I said, it's tiny, not even a milimetre long. I've not noticed any effects in photos taken with it, but such things are supposed to reduce contrast because they scatter light all over the film.
I've heard of a fix where the scratch is filled with black ink or paint - the light is therefore stopped rather than scattered.
Now, I'm interested in this procedure, but can't find any info about how
I should do it. If it's foolproof I'll probably give it a go, but if it is a bit tricky and I risk damaging the lens, I'd let it lie. So has
anyone done this and can give me any advice? Any horror stories about
ruining lenses in this attempt? Anyone want to tell me to stop being so
anal?
q-:
Thanks, David
