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45PSS
Joined: 28 Sep 2001 Posts: 4081 Location: Mid Peninsula, Ca.
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Posted: Fri Dec 10, 2004 4:44 am Post subject: |
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[ This Message was edited by: 45PSS on 2005-12-25 11:10 ] |
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Beezilly
Joined: 08 Dec 2004 Posts: 13 Location: Midwest USA - Indiana
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Posted: Fri Dec 10, 2004 9:28 pm Post subject: |
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I don't have a null type light meter. I have a sekonic digital readout incident light meter which is suposed to function as a spot meter, I think, if the dome is removed.
Couldn't I use my 35 mm SLR built-in meter? Limited to 1/3 EV resolution, but it is reflective. open the LF lens all the way and record meter reading / mark 6.8. Slowly close down the aperture till the meter indicates 1 stop less avail light, mark this point ect . . .
Both the avail light and the tonality of "the scene" would have to held constant I guess.
"Glad to hear you can SEE and are making progress. The peanut butter is more commonly refered to as GLUE, what grease becomes when it has fully dried out. "
Charles
What do human beings become when they have fully dried out?
Lighten up a little bit.
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Henry
Joined: 09 May 2001 Posts: 1648 Location: Allentown, Pennsylvania
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Posted: Fri Dec 10, 2004 9:38 pm Post subject: |
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In my experience the best agent for peanut butter removal is the common gray squirrel. Of course, he may also chew through a few of the more delicate parts of the camera, but it'll keep him away from your bird feeder for a while. |
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45PSS
Joined: 28 Sep 2001 Posts: 4081 Location: Mid Peninsula, Ca.
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Posted: Sat Dec 11, 2004 2:36 am Post subject: |
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[ This Message was edited by: 45PSS on 2005-12-25 11:11 ] |
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Les
Joined: 09 May 2001 Posts: 2682 Location: Detroit, MI
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Posted: Sat Dec 11, 2004 3:51 am Post subject: |
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The common f stop scale wasn't the only attempt at calibrating an aperture.
Around the turn of the century, there was the Unified System or U.S. stops. You'll notice they double EVERY number, while the f stop system doubles EVERY OTHER number.
the rule of thumb to remember is f16 and US 16 are the same.
One stop up and you'll get f22 and US 32 One stop down and you get f11 and US 8 |
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RichS
Joined: 18 Oct 2001 Posts: 1468 Location: South of Rochester, NY
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Posted: Sat Dec 11, 2004 4:14 am Post subject: |
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Since I have lenses that open a bit further than the rated number (wider than say 6.3), I use a different method.
I start off with a known good lens. Set that to the widest common f-stop that both lenses have, say f/8. Mount the known lens and measure that preset f/8 while focused on a white wall with controlled lighting. Remove the known lens, place the new lens and change the arperture until it gives the exact same reading on the meter as the known lens. That's the reference point for all the rest of the readings, one full stop at a time.
Works fine for me...
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Beezilly
Joined: 08 Dec 2004 Posts: 13 Location: Midwest USA - Indiana
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Posted: Sat Dec 11, 2004 4:35 am Post subject: |
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Ah, yes "U.S." does preceed the f/stop numbers on my lens scale. So
U.S. 2.8 4.0 8.0 16 32 64
comm 6.8 8.0 11 16 22 32
Problem solved. Thanks anyway Charles and Rich for the methodology to determine an aperture scale, if need be.
Also I think Les mentioned "around the turn of the century..." I was researching this Dagor lens serial number last night and came up with aprox 1904 as the date of manufacture.
Also as a side note:
This lens was a bonus, I'm not even sure the woman that sold the camera to me on ebay knew it was in the box. Any idea on the value of this lens? I paid $250 for the 3x4 speed graphic (1928-1946 date of MFG), 7 holders, 1 film pack type holder (of no use?), Kalart rangefinder, an analog light meter of somekind (maybe a nulling one afterall), 90 mm Wollensak, 127 (5 in) Dagor, many flash bulbs / accessories, case.
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glennfromwy
Joined: 29 Nov 2001 Posts: 903 Location: S.W. Wyoming
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Posted: Sat Dec 11, 2004 4:27 pm Post subject: |
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Do not use a squirrel to get peanut butter out of your pants!
_________________ Glenn
"Wyoming - Where everybody is somebody else's weirdo" |
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Henry
Joined: 09 May 2001 Posts: 1648 Location: Allentown, Pennsylvania
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Posted: Sat Dec 11, 2004 4:32 pm Post subject: |
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Important safety tip! Thanks, glenn. |
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Beezilly
Joined: 08 Dec 2004 Posts: 13 Location: Midwest USA - Indiana
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Posted: Sat Dec 11, 2004 5:27 pm Post subject: |
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Girfriend handles that ... it can take awhile |
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