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How to set shutterspeeds

 
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Aodhàn



Joined: 06 May 2005
Posts: 7
Location: TheNetherlands

PostPosted: Thu Aug 18, 2005 8:37 pm    Post subject: Reply with quote

I have read the information about tension and aperture settings and studied the table on my speed graphic with the combinations and shutterspeeds available. But I am not clear how to combine this with the shutter speeds that I can choose on the lens.
What settings do I have to use to be able to use the shutter on the lens.
And on what setting should the lens be to use the tension and aperture settings on the camera?

[ This Message was edited by: Aodhàn on 2005-08-18 13:45 ]
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Les



Joined: 09 May 2001
Posts: 2682
Location: Detroit, MI

PostPosted: Thu Aug 18, 2005 8:52 pm    Post subject: Reply with quote

There are TWO shutters on a Speed Graphic. The front one, the one the lens sits in and the rear focal plane shutter.

For the front one, there should be numbers near the outer edge like 400 200 100 50 25 15, etc. Set the dial on the outer edge of the shutter to a particular number (these numbers are actually fractions, ie 400= 1/400) Cock the shutter via the shutter cocking lever and the trip it via the lever near 9 o'clock.

The table refers to the rear focal plane shutter, The shutter has 4 slits on a long sheet much like a window blind. On the left of the camera is a key shaped knob wind it and you'll see in a small round window near by a letter or letters moving past. These letters (or they maybe fractions depending on how old the camera is) correspond to the letters accross the top of the table. Back to the camera, look at the lower left side and you'll see a small knob on a brass plate and another window. This will have a number 1-6. this corresponds to the first column of the table.

The L shaped lever near the wind key is what trips the shutter. just remember that one of the shutters needs to be in the OPEN position in order for the film to be exposed.
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Aodhàn



Joined: 06 May 2005
Posts: 7
Location: TheNetherlands

PostPosted: Thu Aug 18, 2005 9:04 pm    Post subject: Reply with quote

So when I want to use the front shutter on the lens, I have to set the winder on the O of open and when I want to use the rear shutter I have to make sure the front shutter is open and set the dials to the right shutterspeed and trigger the shutter with the lever under the curtain aperture window.
Do you have to press that lever once or do you hold it?
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Les



Joined: 09 May 2001
Posts: 2682
Location: Detroit, MI

PostPosted: Sat Aug 20, 2005 4:10 am    Post subject: Reply with quote

Depending on the shutter there should be either a lever (Graphex) or a round button (supermatic).

Graphiex: with the word Graphex at the top, Cock the shutter via the lever at 1:00, move the lever at 4:00 down and slightly in. This will open the shutter, no shutter speeds need to be moved.

Supermatic. Witht he words "graphic" or "kodak" at the top, cock the shutter via the lever at 12:00 push the button a 1:00 while at the same time trip the shutter with lever at 10:00.

Syncro-Compur. Cock the shutter with lever at 1:00 move round button right near cocking lever in and trip. You'll see a metal finger catch the cock lever if you look at the cocking lever slot.
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Aodhàn



Joined: 06 May 2005
Posts: 7
Location: TheNetherlands

PostPosted: Sat Aug 20, 2005 10:43 pm    Post subject: Reply with quote

Thank you both very much for the reply, I have an Aniversary Speed Graphic and thanks to your help I have found all the necessary levers and wound up keys and am taking it for a spin tomorrow.

Just one more question is the rear curtain shutter more, less, or as reliable as the front curtain in the lens. Ok one more , is there a (relatively) easy way to check the accuracy of the rear curtain.
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t.r.sanford



Joined: 10 Nov 2003
Posts: 812
Location: East Coast (Long Island)

PostPosted: Mon Aug 22, 2005 5:58 pm    Post subject: Reply with quote

As a very, very general rule, the front (leaf) shutter ought to be more accurate; but, of course, everything depends on what condition they are in! If the FP shutter has good spring tension and is clean and traveling freely, it will outperform a gummed-up leaf shutter.

The difficulty about a focal plane shutter, without regard for fatigue of springs or loss of lubrication on bearing surfaces, is that it wants to speed up as the drive roller overcomes the inertia of the curtain and the feed roller. Thus, if nothing is done to frustrate this tendency, the slit will be moving faster when the curtain reaches the bottom of the film gate.

In the old days, it was pointed out that this is not necessarily a bad thing if you are working outdoors in daylight -- the sky is likely to overexpose, anyway, and the faster-moving slit traveling across its (inverted) image might provide a bit of correction.

Miniature cameras with self-capping focal plane shutters compensate for this acceleration by retarding the second curtain's travel, so the effective width of the slit increases with the speed of the curtains. The Graflex FP shutter, of course, is a single curtain. A speed governor is supposed to keep the acceleration under control...

I mention all of this because it bears on your question of testing the shutter. The old standby of photographing a witness-mark rotating on a phonograph turntable, and similar intuitive methods, can't tell you much of what you want to know about the FP shutter.

I think making a few exposures on fairly slow B&W film, under normal shooting conditions, and examining the negatives carefully probably is the most straightforward and satisfactory way to test the rear shutter. If the thing can take good pictures, perhaps you are better off not knowing what it actually is doing!
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Les



Joined: 09 May 2001
Posts: 2682
Location: Detroit, MI

PostPosted: Mon Aug 22, 2005 6:09 pm    Post subject: Reply with quote

I"ll only add that even if stored unwound, your spring is at least 60 years old and suffers from at least a small amount of fatigue.

As a general rule, the speeds with a higher tension will be closer to normal than the low tensioned ones. When I was collecting cameras I always asked the seller to put the tension on 1 and wind the camera all of the way up, then trip until it poops out. Most minis would get through the 1/10th speed but probably slow, T would usually open but rarely would O close. Then I'd wind the tension up to 2,3,4. If I could get it to close when tripping on O at 3 I considered the spring to be good.

That was on 2x3s 4x5s, being taller will take more tension.
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Aodhàn



Joined: 06 May 2005
Posts: 7
Location: TheNetherlands

PostPosted: Tue Aug 23, 2005 8:07 pm    Post subject: Reply with quote

That's a very helpfull reply from both of you. I have done a small test, to be continued. I shot several images with HP4+. I exposed two sheets of film with the same subject on the same spot with the same lighting conditions and used rear curtain for one and lens curtain for the other. I hope it gives me roughly an idea what condition the shutters are in.
They do sound smooth and seem to react pretty quick.
I'll definately try your spring test Les.
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