The Best Exposure Meter

A Light Meter is not an Exposure Meter

Some people call it a light meter, but it’s not. A light meter probably won’t help you with photography. Knowing that there’s slightly more foot-candles or lumens here or there doesn’t help. Knowing what shutter speed you need for a given scene, what f-stop you would need for your fixed shutter speed, that’s useful, and that’s what an exposure meter can tell you.

What’s the best all-time exposure meter?

Hands down, it’s the GE PR-1

Why is the GE PR-1 the best exposure meter?

  1. It’s cheap, maybe all of 10 bucks on eBay including shipping.
  2. It’s built like a tank so just about every single meter ever made is still in circulation
  3. It’s a selenium cell meter so you don’t need a battery.
  4. The zero point is adjustable so you can make sure it’s accurate.
  5. The needle locks into place once you’ve taken your reading.
  6. It has a massive range across two sweeps of the meter so a shift of a given amount of light registers as more movement on the GE PR-1 compared to other meters.
  7. The GE PR-1 “trident” let’s you get readings for bracketing your shot almost instantly
  8. It can measure reflected and incident lighting.
  9. Huge range of film speeds, from ISO .2 to ISO 1600
  10. Huge range of f-stops, from 1 to 128
  11. Huge range of shutter speeds, from 1/3000th to 2 minutes

Use Example

So say you have a Lomography Diana +/F+ and you want to shoot without the lens and do some pinhole work. Grab a tripod and your GE PR-1. The Diana’s pinhole is f-128 just take your reading and you can see immediately that you need a two second exposure or whatever. Yes, you can do that with other meters and just count stops to get the right speed but it’s nice that you don’t have to.

If you have a shot that you absolutely need to have come out, meter it. Then you just do a bit of quick math in your head to bracket it. If you want to bracket but want to mix things up and not have the same shot use the meter. Here’s how, take your reading, and line up the center tine of the trident with the reading. Make your exposure for the f-stop or shutter speed you want. Then if you want to shoot one stop more or less exposed you can just turn the dial to the + or – tines. Easy enough to do in your head, but with the meter you got the information all right in front of you. Want to shoot it a stop under and wide open for some bokeh, read it off the meter. Worried about shake so much you want to use a fast shutter but still shoot a stop over, line up the + tine and read it off the meter.

Can you do that all just counting stops in your head? Absolutely, but just because you can bake a cake from scratch doesn’t mean you shouldn’t buy a box of Betty Crocker for convenience.

Scanned Manuals – Two Versions

GE PR-1 Manual 1 CoverGE PR-1 Manual 2 Cover

Copal SV & Copal MXV Shutter Repair

Issues

If the Copal SV and MXV shutters in your camera (seen in Yashica TLR’s, among others) doesn’t fire, fires but is sticky on slow speeds, or has otherwise broken, chances are it’s a fault in the self timer. Thankfully there’s a easy fix; just take the self timer out. Unless you know what your doing, in which case you wouldn’t bother reading this post, it’s not worth the effort to try and fix and given the frequency with which the self timer jams you shouldn’t be using it anyway.

Required Tools

Small flathead screwdriver set, 1 cotton swab, patience, PVA glue (to re-attach the camera wrap).

How To

Step 1

Peel the leatherette off the front focus assembly. Don’t pry against the edge of the frame or you’ll scratch and ding the lightweight metal. Just wedge the tip of a broad thin screwdriver under one edge and once there’s enough worked up to grab onto pull it up carefully with your fingers.

Step 2

Remove the four largest screws. Once those are out you can lift off the front assembly all in one unit. You can leave those screws for later and work with the camera body attached but it’s easier to lose screws if they drop to the table from the extra two inches or so the body adds. Once it’s off put the body aside. (I didn’t do this but I’ve no fear of losing screws).

Step 3

Now remove the little screws that hold the front focus assembly cover, the ones on the outside edge of the unit. Once those are off you may lift off the thing metal trim piece.

Step 4

Now remove the even smaller screws that hold the bay 1 lens covers and aperture and shutter speed knobs. Lift that off to expose the shutter and lens assembly.

Step 5

Carefully twist off and set aside the tacking lens. This is actually only one half of the tacking lens, the rest is on the underside below the shutter blades. The lower (film-side) taking lens elements can be left in place.

Step 6

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Copal-MXV on Yashica-Mat EM

Give the small silver retaining screw that was hidden under the front element of the taking lens a half screw so that it no longer keeps the scalloped retaining ring locked. Once thats done take and pull off the fuzzy end of your cotton swab so that you have a blunt, paper stick. Push the blunt end into one of the scallops, with a little pressure you should be able to unscrew the retaining ring without scratching or bending anything.

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Retaining ring removed

Step 7

Pull off the marked speed and aperture ring. Once thats out of the way you can lift off the speed cam. Getting it off is a bit easier if you open the aperture up all the way.

Step 8

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Removed lever and lock ring

First pull off the spring arm that rests on top of the self timer escapement, its on the right side. Then locate the small black post with a lock ring on it, Place your finger lightly over it and carefully pry it off with a small screwdriver. Finally check to see if your shutter has a lock-screw holding the self timer escapement in place, if it does it will be at the far left of the escapement, on the inside near the lens mount. If you see a screw there, give it a quarter turn to release the self timer.

Step 9

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Removed self timer casement with lever set to position necessary for removal.

Slowly and carefully remove the self timer escapement from the shutter assembly. It will lift straight up. When it catches on the threaded lens mount cock the self timer lever until it’s toothed gear presents it’s flat side to the lens mount, that will free it up to lift out.

Step 10

Use the lever that projects straight down from the rear of the shutter to cock it and test the shutter a few times. If it all goes well place the speed cam back on and hold it in place while testing the other speeds, they should all fire without lag but the timing accuracy is dependent on the springs strength. If all goes well re-assemble the shutter and reinstall the whole unit.

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Revealed speed cam, place back after self timer removed.

Do You See Them?

I can see them. I am a camera, I think that’s why, that and the light. I’m full of light. It got in during the surgery I think. When they had my chest open? When they had my heart out, just a little out, so they could close up the hole. They said the hole was letting my blood go backwards, letting it out of one chamber or something. Maybe that was it, the hole let the light in too.

 

Closest

Here’s one of them. I hate to be so close but the secret is control. All about control. Keep your mouth tight closed. Keep your eyes tight closed. Don’t let the light out. They can’t see you, not till you let the light out. Do you see it? So close, makes my skin crawl.

Run

See where it went? See it! They run fast, they always run too fast. I think it’s ’cause they know. They have to know. After the first one, after the negative they catch a glimpse, they see. I hate them. I will stop them.

Lomography Diana + & F+ Lenses Field of View

In a previous post I calculated the f-stops of the Cloudy, Partly, and Sunny, settings for the various Lomography Diana + & F+ lenses. Now I will dig out a trig textbook and do the same for the field of view. It bears mentioning that when I type field of view I should be calling it the angle of view. Angle of view is the same thing in a sense but it’s represented by degrees while field of view is properly described as a specific distance. I should first note that this is based on the horizontal field of view and that I performed the calculation for both the 42x42mm mask and 52x52mm mask. After before I figured it out on paper I stuck three strips of tape over the mask, took the back of the camera and sat it on a tripod in my basement (creatively ’cause the tripod socket is on the camera back). That done I put a pair of lamps at the far end of the basement and moved them apart until each bulb just fit in the frame of the 42×42 mask. Then I measured the three sides of the triangle from the lens to each lamp together with the distance of each lamp from the other. Then some different trig calculations were made, those values are called “practical” in the table below. I was only able to do this for the three lenses I currently have. Here’s what I came up with:

20mm Fish-Eye lens

42×42 = 92.8°     52×52 = 105°

38mm Super-Wide lens

42×42 = 57.9°.    52×52 = 68.8°     practical = 53.8°

55mm Wide lens

42×42 = 41.8°     52×52 = 50.6°

75mm Normal lens

42×42 = 31.3°     52×52 = 38.2°     practical = 33.9°

110mm Soft-Telephoto lens

42×42 = 21.6°     52×52 = 26.6°     practical = 24.4°

What’s interesting is that Lomography doesn’t provide this information anywhere that I’ve found unless you count this where they describe the 38mm Super-Wide as “…yielding a 120° view angle.” Or this where the 20mm Fish-Eye is presented as having “[a] 180-degree image!” Which is interesting, as you can then immediately see that the sample images contradict the claim.

Translations from a Box of Soviet Medium Format film (120)

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Свема

Svema

ЦВЕТНАЯ

Color

ДС-4

DS-4

Негативная для дневнога

Negative for the day (daylight color correction)

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45 гост 18 DIN 50 ASA

45 gost 18 DIN 50 ASA

Врем проявл. [7] мин

Development Time [7] min.

Обработать до [09 85]

Process to [09 85] (Use by September 1985)

Партия No [3019]

Party no [3019]

8 кадров 6 x 9 cm

8 frames 6 x 9 cm

12 кадров 6 x 6 cm

12 frames 6 x 6 cm

16 кадров 6 x 4,5 cm

16 frames 6 x 4.5 cm

Цена 95 коп.

Price 95 cop. (copecks)

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СССР

The USSR (Union of the Soviet Socialist Republics)

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шосткинское проиэводствекное обединение „свема“

Shostkinsky (Shostka) production interconnection (association) “Svema”

ТУ 6-17-622-74

TU 6-17-622-74 (no clue)

вскрывать и обрабатывать в темноте

open and handle in the dark (panchromatic film)

Notes:

The translations above were typed into google translate with the help of this online Cyrillic keyboard. Text as printed on the box appears in bold above, and standard type below. Information that was imprinted on the box appears in brackets and translators notes added for clarity appear in parentheses. I don’t know the Russian language beyond a few bits here and there I picked up when I had a lot of enthusiasm for it after reading Gogol’s Dead Souls, great writer Gogol, you should read his work.

Lomography Diana + & F+ f-Stops

110mm Soft Telephoto Lens:

Sunny: f32

Partly: f22

Cloudy: f16

75mm Normal Lens:

Sunny: f22

Partly: f16

Cloudy: f11

55mm Wide Angle Lens:

Sunny: f16

Partly: f11

Cloudy: f8

38mm Super Wide Angle Lens:

Sunny: f11

Partly: f8

Cloudy: f5.6

20mm Fisheye Lens:

Sunny: f5.6

Partly: f4

Cloudy: f3

Source: Published values for the 75mm lens as they appear in Plastic Cameras Lo-fi Photography in the Digital Age by Chris Gatcum. Using those, the aperture diameters were computed as follows: Sunny 3.4mm, Partly 4.7mm, Cloudy 6.8mm. With that aperture f-stops were calculated with the formula: Lens Focal Length / Aperture Diameter = f-Stop