How do you meter with a Pentax K1000?

Question

I have an old Pentx K1000. It has a meter needle on the side of the viewfinder. It meters for wide open aperature. For every f stop I close on it I need to go with a slower shutter speed. I do get the concept. But the reality is that when I stop the aperature down I am not calculating the speed correctly. My shots wide open look good but the more I deviate from wide open (and I am slowing the shutter speed) the darker my prints come out, some to the point of film noise, excessive grain.

Is there an easy way to test the meter, i.e. at noon on a sunny summer day with 100 ASA film with a 35mm f/2.0 lens wide open your speed should be 1/500th sec.

Answer 1

you are slightly off in your calculations. equivilant exposure of f/2.5 @ 1/500 should be f/11 @ 1/30. you're going 5 stops smaller in your aperture so you need to go 5 stops longer on your shutter speed to get the same exposure.

to test out the meter check out the link below. it gives a list of equivilant exposures called exposure values. meter a scene and find that f/stop and shutter speed combo on the chart. then go left and right in that row and shoot each equivilant exposure. since each expsoure is (theoretically) the same. each image should come out the relatively the same. they won't be exact because of depth of field and other factors. but they should all be the same quantity of light.

if you notice some major differences there may be a problem with your camera or light meter. feel free to email me with any questions. i'm a photographer and HS photo teacher.

oh, and there's no way to tell how different shots will come out on a k1000. i have one as well. k1000's do not have a depth of field preview like some of the later minoltas. you just have to trust your abilities.

Answer 2

Equivalent exposures would be:

f/2.5 @ 1/500

f/2.8 @ 1/500 (close enough)

f/4.0 @ 1/250

f/5.6 @ 1/125

f/8.0 @ 1/60

f/11 @ 1/30

f/16 @ 1/15

f/22 @ 1/8



f/11 @ 1/2 second would be overexposed by about 4 stops.



anatoli explained the "Sunny 16 Rule" to check your meter in a professional's terms. In your world, you might try an "average" scene in bright sunlight. Something like the front of your house would do. If you are on ISO/ASA 100, the house should read about f/16 @ 1/100. On the K1000, it might say 1/125, as I don't think there is an available 1/100 speed. At ISO/ASA 200, it would be f/16 @200, etc.



Be aware that some readings are outside the range of your K1000. These would become more of a problem with very bright or very dark subjects. The specifications probably say something like the meter works from EV 1.0 to EV 18.0 at ISO 100. When the meter doesn't work, the needle will jump to an inappropriate location. What I mean is, as you are closing in on the right exposure, bringing the needle closer and closer to the center of the meter, it will all of the sudden jump either to the extreme top or extreme bottom of the meter. This tells you that the scene is not within the meter range. You will soon be able to judge how far the needle moves with each alteration of f-stop or aperture. If you are "one click away" from center, the needle will line up with the edge of the center zone on the meter. You'll get the hang of it. When your meter refuses to take that final reading, just keep going in the direction you were going and estimate the number of stops or shutter speeds you need to go to reach the "virtual center" of the meter.



You know, I forget how the meter works in the K1000. I think it is supposed to actually stop down as you alter your settings. If you change the setting of the shutter speed, it won't change, but if you change the aperture, it will change. If this is not happening, your camera may need service. Maybe you need to ask a new question about that.... I'd check it on my similar Spotmatic for you, but I have not used the meter in that camera sine it broke about 20 years ago.



And don't unscrew your lens! Just slide the A/M switch on the side of the lens to "M" for manual. It will stop down as you go if it is in that position.

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EDIT

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I see Kahless says that the aperture remains wide open until you take the shot. I didn't think they were that sophisticated, but it's been so long since I 've seen a K1000 that you better accept his information as correct.



It's not the stop-down pin mechanism or your shots would be getting lighter instead of darker.



Maybe you just need to get the whole works checked out at a repair shop.

Answer 3

I believe that you are making a fundamental error in the operation of the K1000. It has been many years since I handled one of these but my recollection is that it used wide aperture viewing and focusing but "stop down metering". Pentax was one of the last major camera manufacturers to switch to a full aperture metering system and many of the older lenses could only be used in "stop down" mode on the models that did allow wide aperture operation.



In that case you need to close down the diaphragm manually (most models had a lever or button to press on the camera or the lens to close the aperture for metering) to get a meter reading. Test this by setting the lens to a middle aperture, about f8 or f11, close the lens down to the taking aperture and adjust the shutter speed until the needle is centered, then open the lens three FULL stops, be sure the lens is closed down to that aperture and adjust the shutter speed to center the needle. If it is exactly three settings faster then you need to use the stop down method when metering.



The other possibility is that you are using the wrong battery for the camera. Many of the cameras from that era used mercury batteries that are no longer manufactured. In some cases the substitute batteries are a slightly different voltage and a resistor needs to be added to the metering circuit to accommodate the substitute battery. Any competent repair person can fix that easily.



Hope this helps. Good luck! email me if you have more questions.

Answer 4

If your camera is working correctly and you have the ASA/EI set at 100, your f/stop at f16, your shutter speed should be around 1/100 of a second in bright sunlight. There are a couple things to check on your camera when they get as old as it is. Sometimes the foam rubber which catches the mirror when it goes up, gets sticky like rubber cement. Unscrew the lens and check that. If it is bad, you can get replacement kits for a couple bucks on ebay. It may not affect your exposure, but it will delay the mirror releasing. 2nd, your lens diaphragm could be sticking. While you have the lens off, set it to f/16 and slide the little black lever in the back (it's just to the outside of the protective baffle). That'll open and close your diaphragm. See if it's moving quickly and freely. If not, that's part of your problem. You need to get the lens professionally cleaned, do not use WD 40 to attempt a repair. Your camera does it's meter readings with the lens wide open so you can see what you are taking photos of. A little computer inside couples to the shutter speed and f/stop settings to determine your correct exposure. The diaphragm doesn't close down until you take the photo. 3rd, your shutter speeds could be off. The higher shutter speeds have a tendency to go bad as springs stretch etc. Try to stick to the ones at 1/250th or slower. Good luck. It's a nice camera, I have two. I had my own camera repair business and have repaired close to 100 of them.

Answer 5

i will answer your question, usually i get rubished for telling people the following so here we go again





ok if you open up appeture say F4 then turn on camera inside at night with light on - look around the room up and down eg towards the light and away - does the light meter respond like move around a bit? if yes proceed to next stage if it dont replace batteries, then proceed



Yes its easy to test:



1. got outside bright sunny day no cloud about mid day



2. Set ISO to 100 Appeture to F16



3. now point the camera at your palm (dont worry about focus/make sure palm in the light), should read correct at 1/250th



if you get a grey card it will read 125th, if you read a white piece of paper it will read 1000th





there you go

Answer 6

1

Answer 7

hold the shutter button half way? thats usually how cameras work..



or just buy a seperate light meter.