Shutter time vs. spot meter time

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Good evening,

I've just moved up from medium format to LF. The camera that I have bought is a used MPP made in England about 1961. My question is this: The camera is fitted with a Schneider-Kreuznach-Xenar 1:4.7/135 lens and a Synchro-Compur-P shutter. The shutter times are B, 1,2,5,10,25,50,100,250,500 and my spot meter times are 1,4,8,15,30,60,120,250,500 seconds. Other than placing the indicator on the shutter in an "educated guess" position are there any tricks of the trade that will my beginners delema?

Thanks ahead of time, Bob

-- Bob Passage (bgpassage@earthlink.net), February 03, 2000

Answers

If you're shooting negative film, I wouldn't worry terribly about minor differences between your spot meter and the shutter. If you have to be finicky (shooting transparencies), I would adjust the aperture rather than the shutter (because LF apertures are smooth and continuously while the shutters may not have 1/3 click stops and may not work at intermediate settings - worse, even if they work, they may end up selecting one of the speeds on either side and you won't know which). Good luck. DJ

-- N Dhananjay (ndhanu@umich.edu), February 04, 2000.

It is important to place the indexes on the shutter speed dial so that they line up with each other. Trying to set an "intermediate" shutter speed can cause the cams inside to select the next highest or next lowest speed. Both the older and newer series of numbers will work -- ie: 1/25 is functionally the equivalent of 1/30 etc. In fact, if you take your shutter to a repair facility with an accurate tester, you may well find that 1/50 on your shutter does equal 1/60. If you are in doubt, it would be a good idea to have them run through all the speeds and furnish you a list that shows indicated speed vs actual speed. Many shops will do this for free.

-- Tony Brent (ajbrent@mich.com), February 04, 2000.

A 40 year old mechanical shutter ain't gonna be that accurate anyway. Your 1/5th of a second could easily be 1/4, 1/10th could be 1/8th, etc.

It's generally accepted that exposure only needs to be accurate to 1/3rd of a stop, even for reversal colour film, and the old series shutter speeds are never more than 1/4 stop away from the new ones. If you're that bothered, open or close the iris diaphram a bit to compensate. Light rarely comes in little pre-packed "125th at f/8" sizes anyway.

-- Pete Andrews (p.l.andrews@bham.ac.uk), February 04, 2000.


Bob: I think the shutter speed difference has been well covered, but I would like to comment on the MPP camera. I have one about the same age as yours which I have used for about 4 years now, and I love it. I recently discovered a trick for using my 90mm wide angle which makes using a wide angle easier. The track extension distance for infinity focus with that lens falls at the hinge for the bed, and makes the lens difficult to lock down tight. I found that by moving the track extension to the rear allowed me to mount the lens in the proper place. Unlatch it with the front tab and just slide it to the rear and it will stay there. Sure makes using a wide angle more pleasant. I use ground glass focusing with the 90mm. Enjoy that ol' workhorse. Doug.

-- Doug Paramore (dougmary@alanet.com), February 04, 2000.

First off, I'd just like to say that unless you are hyper critical about exposure times, you probably will not have many problems for negative films, either way, when you use any filters or stop the lens down well times will run down into seconds. However, you may have to braket on slide film or push/pull the development.

By the way, congratulations on buying one of the easier LF cameras to use (even though the movements are a bit restricted.

-- David Kirk (David_J_Kirk@hotmail.com), February 04, 2000.



I agree, you want to vary your aperture, not shutter speed. My old shutter has the same increments. I just extrapolate to set my aperture. I shoot only chromes (and my 60 year old mechanical shutter seems quite accurate, thank you!), and have no trouble getting decent exposure. Analog meters are easier to use for this, I think.

-- Ron Shaw (shaw9@llnl.gov), February 04, 2000.

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