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Re: [APML] Olympus Varimagnifier
Hi Eddie,
Try to get hold of a defect OM-1 body, e.g. one that you can buy for a low
price and re-build just for focusing with. You then either place the screen
in the inner rails in the film chamber or place a knife edge focuser at the
same place. B.t.w. if you place a knife edge focuser that way, make sure to
place the edge of the knife in the same level as where the film emulsion
will be. (There is more to read about this elsewhere. I just can not
remember right now).
Anyway, when you have focused with the "focus body", just lock everything
down and replace it with you ordinary OM-1 body containing film and you know
that you have achieved best possible focus.
Best Regards
Jonas
----- Original Message -----
From: "Eddie Guscott" <eddie.guscott@blueyonder.co.uk>
To: "Discussion of Film Astrophotography" <astro-photo@seds.org>
Sent: Friday, February 06, 2004 7:22 PM
Subject: Re: [APML] Olympus Varimagnifier
> Thank you Philip
>
> The problem is I have 2 OM1's (which I'm happy with) and 1 Nikon F3
>
> I use one of the OM1's just with lenses (stopped down) as much cheaper
than
> the Nikon ones. I also KEF with one OM1 body and attach the other to the
> scope.
>
> With the F3 I've just been trying to get as best a focus as I can get with
> the viewfinder (I tried using a watchmakers loupe on the ground glass
screen
> but couldn't get on with it - it wasn't really a good fit - my diy skills
> showing :-)
>
> So I had 2 options - a varimagnifier for the OM1 or an "improved" loupe or
> better, the consumer fitting (DW4) for the F3.
>
> Guess I'll try having another go at making a loupe to fit the F3
>
> Thank you once again for your advice
>
> Eddie Guscott
>
> PS. Rumour has it we may have some decent weather next week - cold front
> moving in from Iceland...
>
>
> ----- Original Message -----
> From: "Philip Perkins" <pgp@astrocruise.com>
> To: "Discussion of Film Astrophotography" <astro-photo@seds.org>
> Sent: Friday, February 06, 2004 12:36 AM
> Subject: Re: [APML] Olympus Varimagnifier
>
>
> > Hi Eddie,
> >
> > I've never owned a Varimagnifier but this conclusion has been reached
> > pretty consistently by APML over the years. It's intended for 'regular'
> > daylight photography whereas the needs of astrophotography are
> > different. The light is considerably dimmed by passing through the
thick
> > glass of the camera's Pentaprism, bouncing off several surfaces, then
> > further dimmed by passing through the Varimagnifier, involving several
> more
> > glass surfaces, and yet a further prism. Result: the light is so dim
it's
> > hardly useable for astrophotgraphy.
> >
> > If you've already gone the Olympus route then fine - a lot of people
have
> > great success with this camera. In my view a much more elegant solution
> is
> > to dispense with the pentaprism altogether, fit a direct screen viewer /
> > magnifier, and achieve right-angle viewing into the bargain:
> > http://www.astrocruise.com/misc/pb_mount.jpg
> >
> > By fitting a bright screen such as the Red Dot D, and focusing directly
on
> > the screen, the view is dramatically bright - you can easily see the gas
> > clouds of bright nebulae - it is like looking through a low power
> > eyepiece. You can see the full 35mm FOV and focusing is very easy.
Even
> > using the Nikon 300mm f/2.8 lens where the focus point is very critical,
> it
> > snaps into focus, very precisely (I also have a 14x magnifier for
precise
> > focusing). There is no need for a knife edge focuser at all - you are
> > focusing against the manufacturer's calibrated focus point, and you
can't
> > get more accurate then that.
> >
> > The camera is a Nikon F2, and that's a homemade 6x viewer that you see.
I
> > also have the Nikon DW2 which does the same thing except it is much more
> > costly. I use the homemade 6x viewer in preference. Unfortunately I
will
> > probably sell the cameras (I have two F2's) and associated gear quite
> soon.
> >
> > Regards
> > --Philip
> >
> >
> > At 18:21 05/02/2004 +0000, you wrote:
> > >Thanks Robert & Kevin for your honest replies
> > >
> > >Eddie Guscott
> > >
> > >----- Original Message -----
> > >From: "Robert J. Seabold" <bseabold@mn.rr.com>
> > >To: "'Kevin Wigell'" <kwemail@twcny.rr.com>; "'Discussion of Film
> > >Astrophotography'" <astro-photo@seds.org>
> > >Sent: Thursday, February 05, 2004 4:31 AM
> > >Subject: RE: [APML] Olympus Varimagnifier
> > >
> > >
> > > > Not as experienced as you guys but I agree...I bought the
> Varimagnifier
> > > > tried it once and never picked it up again...
> > > >
> > > > Bob Seabold
> > > >
> > > >
> > > >
> > > > -----Original Message-----
> > > > From: astro-photo-bounces@seds.org
> > > > [mailto:astro-photo-bounces@seds.org]On Behalf Of Kevin Wigell
> > > > Sent: Wednesday, February 04, 2004 6:35 PM
> > > > To: Discussion of Film Astrophotography
> > > > Subject: Re: [APML] Olympus Varimagnifier
> > > >
> > > >
> > > > Eddie, yes you can see the entire FOV as the 35 mm frame (using the
> lower
> > > > magnification setting), but the image will be very dim. It's better
to
> > >just
> > > > look through the viewfinder. The view through the varimagnifier will
> just
> > >be
> > > > larger and dimmer.
> > > >
> > > > I have one but virtually never use it. Anyone want to buy it from
me?
> > > >
> > > > Kevin Wigell
> > > > www.kwastronomy.com
> > > >
> > > > ----- Original Message -----
> > > > From: "Eddie Guscott" <eddie.guscott@blueyonder.co.uk>
> > > > To: "APML" <astro-photo@seds.org>
> > > > Sent: Wednesday, February 04, 2004 18:13
> > > > Subject: [APML] Olympus Varimagnifier
> > > >
> > > >
> > > > > Hello All
> > > > >
> > > > > I know there has been several threads on finders for different
> cameras
> > >but
> > > > I
> > > > > just wanted to ask opinion on using the Olumpus Varimagnifier for
> > > > > composition purposes only - not for focussing (as I think I now
> > >understand
> > > > > the knife edge method of focussing and find it reasonably easy to
do
> :-)
> > > > >
> > > > > Will I be able to see the same FOV as the 35mm flm sees? and
thereby
> > > > compose
> > > > > the image easier.
> > > > >
> > > > > Thanks for any comment
> > > > >
> > > > > Eddie Guscott
> > > >
> > > >
> > > > _______________________________________________
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> > > > Astro-Photo@seds.org
> > > > http://seds.org/mailman/listinfo/astro-photo
> > > >
> > > > _______________________________________________
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> > > >
> > >
> > >
> > >_______________________________________________
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> >
> > Philip Perkins
> > <pgp@astrocruise.com>
> > Wiltshire UK & Luberon France
> > http://www.astrocruise.com
> >
> > _______________________________________________
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>
>
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