Minolta Booster groundglass metering
Pam Niedermayer
readings through a set of calculations, probably similar to
those for bellows extension but in the other direction?
Pam
jack Mcgonigle wrote:
>
> I use my Minolta IVF meter with the booster attachment routinely when doing
> close ups involving significant bellows extension. Using multiple readings,
> it is simple to read both shadows and highlights for zone metering. In my
> experience, this system absolutely nails the exposure, better than with my
> Pentax spotmeter. Also, when using the spotmeter, I often forgot to take
> bellows extension into account, resulting in ruined negs. I was extremely
> fortunate about two years ago and was able to purchase a never used, boxed
> set of the IVF, Booster and remote extension for $100. Best photo purchase
> I ever made. This system will also work on the groundglass of my medium
> format cameras (C330 and Rollieflex), and comes with adapters for use on
> 35mm's, but I have never tried this. Pros: Perfect exposure, especially
> when using bellows extension. No lost negs due to failure to add bellows
> compensation. Cons: Is slightly more bother and time consuming than using
> spotmeter.
>
> Jack
>
--
Pamela G. Niedermayer
Pinehill Softworks Inc.
1221 S. Congress Ave., #1225
Austin, TX 78704
512-416-1141
512-416-1440 fax
http://www.pinehill.com
Rupunzel_B
Pam Niedermayer wrote:
>
> Why couldn't you just take spotmeter readings and run the
> readings through a set of calculations, probably similar to
> those for bellows extension but in the other direction?
>
> Pam
when you make take the light reading off the ground glass (better
yet, with a probe in front of the film plane).
Doing so will account for light loss of the lens, variations in
true lens aperture, bellows factor and other things that can not
be accounted for by taking a meter reading at the source and
calculating the bellows factor.
The difference is similar to theoretical =vs= real world.
Film plane metering usually delivers the most accurate results.
Bernice
Pam Niedermayer
a spot meter to take the film plane and/or ground glass
readings. Why is some booster needed for the Minolta?
Pam
--
Fred
meters it is self-powered and it essentially boosts the meter readings
through the attachements and low light levels so that the light
meter's sensor gets enough light (such as through the lens and bellows
to the ground glass) to measure and perform calculations. the booster
has a dial that adjusts sensitivity as needed.
On Thu, 06 Jan 2000 00:04:30 -0600, Pam Niedermayer
<pam_...@cape.com> wrotf:
Rupunzel_B
Pam Niedermayer wrote:
>
> Sorry, I wasn't clear, I was asking why I couldn't just use
> a spot meter to take the film plane and/or ground glass
> readings. Why is some booster needed for the Minolta?
>
> Pam
Your spot meter does not have the sensitivity to make this
measurement most of the time.
You would also need to block out extraneous light while making
the measurement.
This makes using a spot meter to measure the light off the GG a
bit difficult.
Bernice
Pam Niedermayer
booster pack, more than $400 at B&H. Lot of money (I like
your $100 deal, Fred), but this (ground glass readings)
seems like such a logical thing to do. Oh, well, maybe in a
few months. Would be cool to have a light sensitive ground
glass that you could touch to get a LCD readout.
Pam
--
KEYSAL
meter I
plan to use the Booster for. >>
If I recall correctly the Minolta Booster ii will only work on a few Minolta
meters that have the electrical plug in for them. I may be wrong on this and
other brands may have adopted the plug socket to accomodate this unit, but I
havent heard of them.
Im not a big fan of this type of metering because it is measured through the
ground glass instead of inside the camera where the film will see the light.
Ground glass metering requires a calibrating procedure to compensate the light
reduction for that particular ground glass before using. Switching to another
ground glass requires recalibrating. Plus I have always distrusted what affect
metering an area of ground glass that had a grid line under the meter probe.
Would that throw it off? For simplicity sake I really like metering inside the
camera directly infront of the where the film will be. Nothing to recalibrate
and all the benefits.
Keysal
OorQue
front of the where the film will be. Nothing to recalibrate and all the
>benefits.
I agree and frequently use a Horseman meter that slides behind the ground glass
of my Galvin 2x3 (they also make a 4x5 version but it doesn't measure the full
frame). One thing I like about this meter is that it makes bracketing in 1/3
stops really easy since I can simply watch the meter reading change as I vary
the f/stop ... in view of the variability of the speeds on all my shutters, I
much prefer to bracket with f/stops since I've found it to be more accurate
than doing it with shutter speed. I've also found this meter works great with
close-up shots since it automatically adjusts exposure for bellows extension
and magnification ratio...
Of course, there are still situations when full-frame averaging doesn't work
very well so I always keep my spot-meter handy, just in case.
JG
Clyde Soles
> Im not a big fan of this type of metering because it is measured through the
> ground glass instead of inside the camera where the film will see the light.
> Ground glass metering requires a calibrating procedure to compensate the light
> reduction for that particular ground glass before using. Switching to another
> ground glass requires recalibrating. Plus I have always distrusted what affect
> metering an area of ground glass that had a grid line under the meter probe.
> Would that throw it off? For simplicity sake I really like metering inside the
> camera directly infront of the where the film will be. Nothing to recalibrate
> and all the benefits.
I occassionally use a fiber optic probe on a ground glass and have never
had any problems. Calibration is simple and only needs to be done once
for each gg. Never noticed any problem with grid lines. I'm sure
in-camera metering is a tad more accurate (and a lot more expensive).
But, since I get good results, I'll stick with what works.
--
DISCLAIMER: Unless otherwise indicated, this post is personal
opinion and NOT an official statement of my employer.
Pam Niedermayer
see what area you're metering?
Pam
KEYSAL wrote:
>
> Im not a big fan of this type of metering because it is measured through the
> ground glass instead of inside the camera where the film will see the light.
> Ground glass metering requires a calibrating procedure to compensate the light
> reduction for that particular ground glass before using. Switching to another
> ground glass requires recalibrating. Plus I have always distrusted what affect
> metering an area of ground glass that had a grid line under the meter probe.
> Would that throw it off? For simplicity sake I really like metering inside the
> camera directly infront of the where the film will be. Nothing to recalibrate
> and all the benefits.
>
> Keysal
Victor Bazarov
> So, how do you meter inside the camera? While being able to
> see what area you're metering?
>
> Pam
The meter probe is inserted between the camera back and the ground glass.
You see the image on the ground glass and the probe's outline (dark).
You position the probe so its head is in the required location in the
frame. Then take reading on the meter (it stays outside the camera).
Something like:
______
[______] <- meter
_)
( <- cord
+---------)----+
| +==========+ | <- camera
| || / || |
| || / || | <- probe behind
| || o || | ground glass
| +==========+ |
+--------------+
###
HTH
Victor
P.S. It seems that you could use a book on LF. All books I saw do
actually have the noted technique described (with pictures).
--
Please remove capital A's from my address when replying by mail
Pam Niedermayer
to large format, picking up my Bender 8 X 10 kit Sunday; but
I can't decide which book to get. Also have ordered the
Bender pinhole information kit, which includes a book by
Schull. Thought I'd read what the Bender instruction manual
and Schull had to say, assemble this honey, go from there.
Any recommendations?
Pam
KEYSAL
If you go to http://www.sekonic.com/Products/L-508.html, you will see that the
booster unit at the bottom of the page is one and the same as the Minolta
Booster II (and then they tell you that it's compatible with the Minolta
branded
booster), but almost no one sells a Sekonic one! >>
Im going to have to check this one out, I had no idea they made this. Once
again the rec.photo.equipment.large-format comes through again with useful
info. Thanks for the link. Whoops just tried click the link and no go. I will
try it manually later.
<< I just bought the Booster II today for my Sekonic. I just can't wait to go
play
with it. >>
Ironic. My Spot meter attachment for my Sekonic 328 just arrived from KEH today
also. Tomorrows trip is going to be its first excursion with me. With all this
good information I may have to refigure which meter I carry, or at least which
one I use in the studio.
The Sinar probe hook up is very interesting to me. I could have sworn I saw
somewhere a simple film back insert that you could place into any 4x5 film back
just like an open film holder. It had an opening in the side for the sinar
probe to slide in and the back was open so you could see the area you are
metering. Granted the image you see will be pushed out of focus while metering
but you can still figure out what your metering the probe metering cell would
be exactly where the film would be.The only downside to this method is you need
to use the dark cloth to cover the openings and ground glass when making the
actual meter reading. I havent seen one of these things in years and dont know
if Sinar or anyone makes one. Has anyone seen one of these used or new?
Keysal
Victor Bazarov
> Thank you. You're right about getting a book, I'm brand new
> to large format, picking up my Bender 8 X 10 kit Sunday; but
> I can't decide which book to get. Also have ordered the
> Bender pinhole information kit, which includes a book by
> Schull. Thought I'd read what the Bender instruction manual
> and Schull had to say, assemble this honey, go from there.
> Any recommendations?
>
> Pam
Being a novice myself, I decided on two books so far: "Large
Format Photography (Kodak publication, No. O-18E.)" by Roger
Vail, Easkman Kodak Company, James A. McDonald, and "Stroebel's
View Camera Basics" by Leslie Stroebel. With time I will
probably pick up more books on film development, etc.
I have a Crown Graphic 4x5. Damn it, the results ARE satisfying
when I don't screw up. But again, that's how I learn... :-)
Victor
William Wallick
WW
Tan wrote:
> The Sekonic L508 has a socket. And it works the same.
>
> If you go to http://www.sekonic.com/Products/L-508.html, you will see that the
> booster unit at the bottom of the page is one and the same as the Minolta
> Booster II (and then they tell you that it's compatible with the Minolta branded
> booster), but almost no one sells a Sekonic one!
>
> It also takes a Sinar probe.
>
> Well, it is a 'correlation' way of metering, but there's really nothing too
> difficult about the calibration really. And recalibration is a cinch.
>
> That's a good point what you say about the probe sensor spot falling on a grid
> line. Well, I suppose that can be a problem, but I suspect that most scenes will
> have spots that I can meter off without having a blocking grid line. We'll see.
>
> I own a clear groundglass and a gridded one, maybe that will help too..
>
> It's true that in front of the glass is best. There is no question about it. But
> a whole metering system like that costs a fortune if I have to pay Sinar some
> money for the probe, and change the back to one where I can stick a probe in!
> This compared to a relatively cheap booster if you already own a suitable meter.
>
> I suppose there are pros and cons to the whole thing eh?
>
> But I am quite sold on not having to carry a little tape measure and having to
> work out the maths.
>
> I just bought the Booster II today for my Sekonic. I just can't wait to go play
> with it.
>
> On 07 Jan 2000 12:50:42 GMT, key...@aol.com (KEYSAL) typed:
>
> ><< BTW, you can plug the Booster II into a Sekonic L508 as well. That's the
> >meter I
> >plan to use the Booster for. >>
> >
> >If I recall correctly the Minolta Booster ii will only work on a few Minolta
> >meters that have the electrical plug in for them. I may be wrong on this and
> >other brands may have adopted the plug socket to accomodate this unit, but I
> >havent heard of them.
> >
> >Im not a big fan of this type of metering because it is measured through the
> >ground glass instead of inside the camera where the film will see the light.
> >Ground glass metering requires a calibrating procedure to compensate the light
> >reduction for that particular ground glass before using. Switching to another
> >ground glass requires recalibrating. Plus I have always distrusted what affect
> >metering an area of ground glass that had a grid line under the meter probe.
> >Would that throw it off? For simplicity sake I really like metering inside the
> >camera directly infront of the where the film will be. Nothing to recalibrate
> >and all the benefits.
> >
> >Keysal
>
> *********************************************
>
> delete "NOSPAMDIET" to reply via email
William Wallick
for the ground-glass, another is for attaching to a microscope, and the third is for
metering the film plane of 35mm cameras (I know, I know, don't even start....).
Looks pretty cool but I haven't had a chance to use it yet.
The ground-glass attachment measures a 5mm circle and works with both flash and
ambient light.
Someone asked about calibration. The instructions have you meter (with the booster) a
grey card. You then meter the grey card (same lighting of course) at the
ground-glass. You enter this compensation factor on a dial that is on the booster.
You are calibrated.
Like I said, I haven't done it yet.
WW
Pam Niedermayer
Pam
William Wallick wrote:
>
> I should also have mentioned that it comes with three attachments: one is, of course,
> for the ground-glass, another is for attaching to a microscope, and the third is for
> metering the film plane of 35mm cameras (I know, I know, don't even start....).
> Looks pretty cool but I haven't had a chance to use it yet.
>
> The ground-glass attachment measures a 5mm circle and works with both flash and
> ambient light.
>
> Someone asked about calibration. The instructions have you meter (with the booster) a
> grey card. You then meter the grey card (same lighting of course) at the
> ground-glass. You enter this compensation factor on a dial that is on the booster.
> You are calibrated.
>
--
William Wallick
theoretically measuring in FRONT of the ground glass should be more accurate how much of a
diffeerence REAL WORLD this makes is uncertain. Might be an interesting experiment to look
into. On the other hand it seems that once you have factored in the light loss of the
ground-glass itself you should be on (or near) an equal footing with the other method.
Vadim raised an interesting question bout measuring a shorter lens off axis. I think this
would be a metering concern that would potentially affect either method. Maybe when I get
set up (and time) i could fill the ground-glass with an evenly lit gray card and use the
booser to measure all across the ground-glass and see what sort of fall-off there is.
Interesting subject,
WW
William Wallick
Is there a FAQ for the group?
Thanks,
William Wallick