Keith Slater , Jan 27, 2005; 12:16 a.m.
I do not own a light meter and have been using the "sunny 16" rule. I
was given a old GE Type pr-35 exposure meter and was wondering if it
is worth using. Is there anyway to test it, such as point at a 100
watt bulb from a certain distance should read X at a certain shutter
speed and film selection? The shutter speed goes up to 1000, and the
film selection goes to 400. There is also a exposure value selection,
I am unsure what that does. The light meter is nice and small and
fits in my pocket well. One other question about depth of field. My
photography book says that "When the lens is stopped down, (at its
smallest aperture) the depth of field of field is at its maximum." I
am unsure what this means, does stopped down mean (on my ansco viking)
f6.3 is the smallest, or f32? I understand the smaller the f stop the
larger the aperture.
Thanks, Keith
Ma Ho Fong , Jan 27, 2005; 12:22 a.m.
The depth of field is at its maximum when the aperture is at minimum, in your case f32.
Keith Slater , Jan 27, 2005; 12:27 a.m.
Richie Cruz , Jan 27, 2005; 01:21 a.m.
As long as it is responsive to light old selenium style meters like the one that you have can be handy. You just have to remember to keep them away from moisture, which is their weak point.
I have an old Sekonic, and have found that it is useful for cloudy days and twilight. However, they do not work that well indoors or at night. But if you are using the "sunny f16" rule, I doubt that matters.
The way I figured out if my Sekonic was working was to check it on a classic "sunny f16" day. It read 1/400 at f16, when it was set for ISO 400 film. I figured it was fine, and my pictures turn out alright.
Hope that helps, Richie
Mike Kovacs , Jan 27, 2005; 09:14 a.m.
Do you not have another exposure meter to compare it against? You can compare against a reflective meter by using both in reflective mode, or being careful to chose a neutral grey subject to compare against an incident meter.
Ed Balko , Jan 27, 2005; 09:37 a.m.
Take a look at:
http://www.zoo.utoronto.ca/able/volumes/vol-12/13-slaughter.pdf
for a simple calibration/testing method.
There is also a second method on one of the old meter websites that involves pointing the meter at the north sky and calibrating to an EV reading. Perhaps someone else remembers where to find the website.
Ron Gratz , Jan 27, 2005; 11:35 a.m.
I use an old Zeiss-Ikon Ikophot selenium light meter when I take out my Super Ikonta C and found it works just fine. Note that I only shoot Black & White film which has a fair tolerance for over/underexposure. Color print film does too but transparency film does not.
To check your meter - you must know someone with a 35mm camera that has a built in light meter. Get together with that person and set the same film speed, eg ISO 400, on your meter and on your friend's camera. Then have your friend give you the exposure readings using his camera for a variety of settings - sky, shade, light objects (eg concrete), dark objects, (eg tarred street) and neutral (eg sun-lit grass). At the same time, see what your meter tells you. If you are close and are using B&W or color print film, you should be fine.
Ron Gratz
dave collopy , Jan 27, 2005; 08:46 p.m.
Your GE meter is definitely worth using. I use a GE pr1, carry it with me everywhere I go. The GE meters are very rugged, very responsive and highly accurate. You'll only be able to use it out of doors though, the range is somewhat limited. Also test it for accuracy regularly, grey card in full sunlight = f/16 @ 1/100th @ ASA100. When the selenium cell does go out it won't go out all at once.
David M , Jan 27, 2005; 09:46 p.m.
A 1950's Zeiss Ikophot is my main light meter. But they are about the only old light meters that seem to continue to work. If it works and is accurate its worth using, if not it isn't. Pretty obvious really.
Larry Mobbs , Jan 27, 2005; 11:20 p.m.
I purchased two Ikophots from ebay and fell in love with them. My friend was so impressed we had to get him one as well and they all worked dead on for accuracy. Each one came in that beautiful leather case they made that holds the direct light shield.
I read somewhere that keeping these units in cases was a key to long life.
