[pure-silver] Re: old rollei over exposing
- From: titrisol <titrisol@xxxxxxxxx>
- To: pure-silver@xxxxxxxxxxxxx
- Date: Fri, 18 Feb 2005 13:41:41 -0800 (PST)
I remember the TV-screen method for testing shutter speeds...
Or if you have acces to a strobo-light you maybe able to record
a pendulum/metronome with a dark background and see how long it
travels.
--- Richard Knoppow <dickburk@xxxxxxxxxxxxx> wrote:
>
> ----- Original Message -----
> From: "Shannon Stoney" <sstoney@xxxxxxx>
> To: <pure-silver@xxxxxxxxxxxxx>
> Sent: Friday, February 18, 2005 8:23 AM
> Subject: [pure-silver] Re: old rollei over exposing
>
>
> > >I agree with Mr. Knoppow,
> >>
> >>Though both of the failed mainsprings I've actually seen
> >>were broken as a
> >>result of a crack started from a spot of surface
> >>corrosion.
> >>
> >>I have seen several synchro-compurs on old Rolleiflex MX's
> >>that were just
> >>plain worn out. The first symptom is usually a failure to
> >>cock the shutter
> >>when the board is extended outward. The wear on all the
> >>cocking mechanism
> >>parts stacks up to the point where there isn't enough
> >>travel left to quite
> >>cock the shutter. Generally the shutter would still
> >>function if you could
> >>cock it manually, but even then it feels pretty rough
> >>while the shutter is
> >>being cocked. Theres a steel toothed ring that bears on
> >>the aluminum
> >>housing, and that's one of the main wear points. These
> >>shutters are on
> >>either heavily used cameras, or have a lot of dirt in
> >>them.
> >
> >
> > thanks for all the advice about this. I called the guy who
> > repaired
> > my rollei, and he said that he had checked it after
> > adjustment and
> > the shutter was working fine. I am beginning to believe
> > that the
> > reason I think the film is overexposed is that Ilford's
> > HP5+ roll
> > film is actually a very fast film, and shadow densities
> > fall in the
> > 0.7 range by design (by Ilford). I THINK my exposures are
> > too dense,
> > by inspection and by densitometer measurement, but Ilford
> > wants them
> > that way, so fine. Printing times will just be longer.
> >
> > By the way, you might find it amusing that Eudora thought
> > that your
> > message, quoted above, contained language that some might
> > find
> > offensive. ;-) Can't think what it might be:
> > "corrosion"?
> > "crack"? "rough"? In any event, there were two hot
> > peppers next to
> > it.
> >
> > --shannon
> >
> Well, checking with the guy is not going to tell you if
> the shutter is accurate, you must measure it in some way.
> Ilford claims they do not use the ISO method of measuring
> speed. The ISO method effectively specifies a contrast
> index. This value of CI is fairly high, suitable for contact
> printing and diffusion enlarging, perhaps even a bit high
> for that. Ilford rates the film when it is developed for a
> contrast index midway between that required for diffusion
> enlargers and that for condenser enlargers. The results you
> get should still be full range negatives. If measured by the
> ISO method the film will probably be a little faster than
> the Ilford numbers but probably by no more than half a stop.
> If the negatives are over exposed (dense but of normal
> contrast) the most likely culprit is the shutter unless the
> stop linkage is somehow not working right. This last can be
> checked easily by seeing if the iris is fully oped when the
> indicator is at the maximum stop and not some other point.
> This can happen if the camera is butched badly in repair. My
> vote is the shutter.
> See if someone in your area has a shutter tester and will
> check the shutter. The Calumet tester I mentioned is nice to
> have but is too expensive for a single test.
>
> ---
> Richard Knoppow
> Los Angeles, CA, USA
> dickburk@xxxxxxxxxxxxx
>
>
=============================================================================================================
> To unsubscribe from this list, go to www.freelists.org and
> logon to your account (the same e-mail address and password
> you set-up when you subscribed,) and unsubscribe from there.
>
__________________________________
Do you Yahoo!?
Yahoo! Mail - Find what you need with new enhanced search.
http://info.mail.yahoo.com/mail_250
=============================================================================================================
To unsubscribe from this list, go to www.freelists.org and logon to your
account (the same e-mail address and password you set-up when you subscribed,)
and unsubscribe from there.
Other related posts: