[M]: RE: RE: RE: (focussing screens)
| Subject: | [M]: RE: RE: RE: (focussing screens) |
| From: | Heath, Andrew |
| Date: | Tue Mar 23 02:05:55 1999 |
What I forgort to mention was the fact that there were reference lines
etched on the screen too.What I ended up with was a crystal clear
rangefinder in the middle, a clear strip to one side with the etched lines
on it and the rest of the matt finish around the outside was polished down
but not completley. Incidentally, the clear strip appears to have been
polished in such a way that when you have an out of focus star image you get
four pinpoints of light that converge together as you bring the image to
focus.It appears to work quite well for me.
Andy Heath.
> -----Original Message-----
> From: Heapy Chris CG [SMTP:Chris.Heapy@ALDERLEY.zeneca.com]
> Sent: 23 March 1999 08:53
> To: mapug@shore.net
> Subject: [M]: RE: RE: (focussing screens)
>
> This is not really a great idea - unless you also include a reference grid
> for your eye to focus on. A clear screen means you have to rely on viewing
> the virtual image and your eye will compensate if its a bit out-of-focus,
> achieving accurate focus is therefore made difficult. You can make a
> standard screen much brighter by rubbing a tiny amount of
> grease/oil/wax-polish/WD40 or whatever on the matt side, at least this is
> reversible! Also, there is little difference between a clear screen and no
> screen - just temporarily remove it if you want to try the clear option.
> At one time I had made a clear screen for my OM1 from a piece of
> microscope
> slide with fine lines etched on it, this was very bright indeed but
> singularly useless for focussing (difficult even with the reference
> lines).
>
> Chris Heapy
>
> > ----------
> > From: Heath, Andrew[SMTP:ah40096@glaxowellcome.co.uk]
> > Sent: 23 March 1999 07:53
> > To: mapug@shore.net
> > Subject: [M]: RE:
> > Importance: High
> >
> > Clive,
> >
> > I have a Nikon FA and recently posted the focusing screen up to a chap
> in
> > Cumbria who polished the matt part of it down until it was clear, he
> also
> > polished down the rangefinder segment in the middle until it was clear
> > too!!
> > If you require further details let me know, by the way it only cost me
>
etched on the screen too.What I ended up with was a crystal clear
rangefinder in the middle, a clear strip to one side with the etched lines
on it and the rest of the matt finish around the outside was polished down
but not completley. Incidentally, the clear strip appears to have been
polished in such a way that when you have an out of focus star image you get
four pinpoints of light that converge together as you bring the image to
focus.It appears to work quite well for me.
Andy Heath.
> -----Original Message-----
> From: Heapy Chris CG [SMTP:Chris.Heapy@ALDERLEY.zeneca.com]
> Sent: 23 March 1999 08:53
> To: mapug@shore.net
> Subject: [M]: RE: RE: (focussing screens)
>
> This is not really a great idea - unless you also include a reference grid
> for your eye to focus on. A clear screen means you have to rely on viewing
> the virtual image and your eye will compensate if its a bit out-of-focus,
> achieving accurate focus is therefore made difficult. You can make a
> standard screen much brighter by rubbing a tiny amount of
> grease/oil/wax-polish/WD40 or whatever on the matt side, at least this is
> reversible! Also, there is little difference between a clear screen and no
> screen - just temporarily remove it if you want to try the clear option.
> At one time I had made a clear screen for my OM1 from a piece of
> microscope
> slide with fine lines etched on it, this was very bright indeed but
> singularly useless for focussing (difficult even with the reference
> lines).
>
> Chris Heapy
>
> > ----------
> > From: Heath, Andrew[SMTP:ah40096@glaxowellcome.co.uk]
> > Sent: 23 March 1999 07:53
> > To: mapug@shore.net
> > Subject: [M]: RE:
> > Importance: High
> >
> > Clive,
> >
> > I have a Nikon FA and recently posted the focusing screen up to a chap
> in
> > Cumbria who polished the matt part of it down until it was clear, he
> also
> > polished down the rangefinder segment in the middle until it was clear
> > too!!
> > If you require further details let me know, by the way it only cost me
>
