<font size=-1>[ This Message was edited by: 45PSS on 2005-12-25 11:10 ]</font>

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.

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.

<font size=-1>[ This Message was edited by: 45PSS on 2005-12-25 11:11 ]</font>

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

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...

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.

Do not use a squirrel to get peanut butter out of your pants!

Important safety tip! Thanks, glenn.

Girfriend handles that ... it can take awhile