Overexposed

January 8, 2005 5:28 AM

[CameraFilter] I have a Pentax K1000. The last two rolls of film I've gotten developed (a generic-brand ISO 200 and a Fuji ISO 100) have had a major problem - the first couple of pictures turn out alright, then the last couple of pictures, but everything in between is overexposed. My first thought was a light leak when I changed lenses, but then I realized an earlier roll came out just fine, and I'd used different lenses on it. Any ideas?
posted by emmling to sports, hobbies, & recreation (19 comments total)

Some questions:

1. Have you tried shooting a complete roll with one lens?
2. When you shoot a roll, are you sure the film is advancing?
a. When you shoot a 36-roll, do you get approximately 36 shots?
b. Are the shots completely white, or just overexposed? Any double-exposures?
3. Have you tried shooting the same subject with the same exposure for all the frames?
posted by Civil_Disobedient at 6:55 AM on January 8, 2005

All good questions from C_D. To get a good handle on what's going on you're probably going to have to waste a few rolls of film.
posted by RustyBrooks at 7:12 AM on January 8, 2005

1. Have you tried shooting a complete roll with one lens?
- Working on that at the moment.

2. When you shoot a roll, are you sure the film is advancing?
- Yeah.
a. When you shoot a 36-roll, do you get approximately 36 shots?
- Yeah.
b. Are the shots completely white, or just overexposed? Any double-exposures?
- Most of them are completely white, but there're one or two that look just way overexposed. No doubles that I can tell.

3. Have you tried shooting the same subject with the same exposure for all the frames?
- No, but I'll work on it.

At least I get a free roll of film everytime I get one developed. That's going to keep the cost of this down slightly, I think.
posted by emmling at 7:43 AM on January 8, 2005

also, it's possible that one of your lenses has the light leak.
posted by dorian at 8:05 AM on January 8, 2005

A low battery can cause incorrect readings from the light meter. Also, verify the film speed dial is set correctly, and not in between notches?
posted by one at 9:16 AM on January 8, 2005

After checking all that, you may want to take it to a camera shop and have the mechanism cleaned; there could be something sticking?
posted by Doohickie at 10:05 AM on January 8, 2005

I'd say it was exposure wierdness, but you'd almost certainly notice if your shots were 20 seconds at f/3.5 on a bright, sunny day (for example).

I'm still trying to figure out why the problem would only be in the middle of the film and not the beginning or end. If it were a light leak, you'd expect it across the roll. If it were a lens malfunction, again, it wouldn't be in the middle of the roll. If it's the advance mechanism, you wouldn't be getting 36 shots. Quite a doozy.
posted by Civil_Disobedient at 10:28 AM on January 8, 2005

I'm assuming you looked at the film negatives to make sure that they're pretty much solid black, to eliminate a printing problem at the print shop?

It wouldn't take 20 seconds to fully overexpose in direct sunlight. Hell, in a lot of cases 1/2 second or less might do it. It wouldn't be hard to tell if the shutter is sticking, just hold the camera with the lens facing you and take a picture. If I recall correctly the pentax k1000 is fully manual, right? It gives an exposure reading but you manually have to set the time and aperture? If so it should be pretty plain if the meter says to use 1/60 second and you're clearly getting 1/2 second.

But yeah, why would the first couple and last couple of exposures be ok, on more than one roll of film? That's a doozy.

You might try posting on photo.net. It's been years since I hung out there but back in the day it was populated by photo nerds, repair guys, pro photographers, and dedicated amateurs, so maybe it still is.
posted by RustyBrooks at 11:27 AM on January 8, 2005

I'm also puzzled by the fact that it's only happening in the middle of the roll.

I think the problem could be with your lab. (This is how I got through college, so it's something I know a bit about.) The negs are taped to a card and run through the developer. The card has holes that run across a cog -- this is what advances it through the machine. It could be that the C-41 developer has a problem -- the card could be feeding properly as it enters and leaves the machine, but could be bogging down somewhere in the middle. The negs in the middle of the roll might be spending too much time in a certain chemical.

What do you think? Try taking the rolls to a different lab and see if it makes a difference.
posted by mudpuppie at 11:33 AM on January 8, 2005

[Long-time Pentax guy here] The K1000 is a totally manual camera. The light meter does not set the exposure. It's just a needle thingy. Which brings up some more questions.

How experienced are you with using the camera? (Do you know how to properly meter an exposure and when to trust it and when not to?)

Is the battery fresh? The K1000 battery is ONLY for the light meter--the camera itself is totally mechanical. It will work perfectly fine without a battery in it. If the battery is weak then the meter reading will be off and if you trust it you will be overexposing the shots.

Over what period of time do you shoot a roll? If you shoot a bunch of pics and leave just a few exposures to finish off later that explains the behavior as well. When the battery is working the first few frames are OK. Then as it drains the middle of the roll is overexposed. Then you come back a few days later to finish and it's OK again.

How about flash shots? You set the exposure from the guide on the flash there. Are they OK?

Shoot a roll of outdoor pics on a sunny day and forget about the meter readings but just use the "Sunny 16" rule instead. Set the shutter speed as close as possible to the ISO of the film you're using (i.e., 1/125 for ISO 100, 1/200 for ISO 200, etc.) and set the aperture to f/16. How does it do now?
posted by AstroGuy at 12:36 PM on January 8, 2005

When I read your description, I thought "lab problem". Make sure your negs are not fogged, the film base area running down the sprockets should be consistent. Of course I don't know whether you're referring to the negs or to a batch of prints when you say "first couple of pictures".

To cut down costs on blowing rolls, some 1/2 hour joints (and of course full service labs) will process uncut negs for around $2.50. That makes you feel less guilty about shooting useless frames.
posted by Jack Karaoke at 2:52 PM on January 8, 2005

Look at the negatives. If the negatives have black squares, the problem is with your camera's metering or shutter. If the negatives have huge splotches and the splotches go all the way out to the edge and include the perforations for the cog wheels, then the problem is a light leak either in your camera, with the film canister, or at the lab. If the splotches or black strip does not go all the way into the cog wheels, the problem is very likely to be with your shutter sticking open, with the winding mechanism, or otherwise in the internals of your camera.
posted by SpecialK at 3:35 PM on January 8, 2005

(* General note: When you have an exposure problem, you generally won't be able to tell anything by looking at the prints. You need to go back and look at the negatives. The reason for this is that the prints are subject to a bunch of different variables that have nothing to do with your negatives, including print processor chemistry, operator knowledge, paper type, and processor hardware. This is why some minilabs charge a lot more than others -- as a talented photographic processor with many years of experience and a good eye for color adjustments, I can generally make $15/hour working as a minilab tech, and I produce prints with very even color profiles. The people who work in grocery or drug stores are generally paid either minimum wage or about $8/hour, and run the machines on automatic. If you don't believe that this makes a difference, you should.)
posted by SpecialK at 3:43 PM on January 8, 2005

Um, folks, just want to clarify something. If the shots are overexposed, the negs will be clear, not black.

I used to own a K-1000 as well (didn't everyone). Shooting an entire roll of the same exposure for the same subject should give you identical results if the camera if operating properly. This will at least eliminate one variable from the equation.

It wouldn't take 20 seconds to fully overexpose in direct sunlight.

It could. Small aperature/dark subject matter. Like I said, it's unlikely; the poster would have noticed widely different exposure times. The difference between a properly exposed shot and a clear neg is 5 stops. That's the difference between a 1/60th sec. exposure and a half a second. You'd definately notice that.
posted by Civil_Disobedient at 4:36 PM on January 8, 2005

(Does more thinking...) Oh jeez, I think I've shot too much slide film. That first statement might be reversed. Damn C41.
posted by Civil_Disobedient at 4:41 PM on January 8, 2005

CD: Right. Think "negative." Anyway, what you said about taking a roll of identical shots is true assuming the camera is mechanically OK. But if the battery is low like I'm guessing and she's using the meter a lot it will get progressively worse through the roll.
posted by AstroGuy at 8:23 PM on January 8, 2005

Oooh, I hadn't thought about the battery/light meter! That makes me a lot more hopeful about this than I was yesterday.

I've been using my dad's K1000 for nearly 10 years now, but this camera is very new to me. I only got it in late September, just before I moved to Japan. (yeah, complicates things a bit, doesn't it?) It's very possible the battery is dying.

My negatives are coming back clear. I don't have a flash for this camera yet, so that doesn't come into play at all. I tend to shoot a little bit at a time, but the last couple of rolls have been for specific "I'm going out to take pictures" events, and were used entirely in one go.
posted by emmling at 3:36 AM on January 9, 2005

If the negatives are clear there is underexposure, not overexposure, and there may be a mechanical problem with the shutter. It still could be a metering thing though. Shoot a roll of all the same thing at the same exposure setting and get the film developed (negatives only). All frames should look identical. If they don't, you've got a shutter problem.
posted by AstroGuy at 8:52 PM on January 9, 2005

[sigh] Yeah, like Civil_Disobedient I've been shooting slide film for too long.

Thanks for the help, everyone - I replaced the battery and everything's working fine now. :)
posted by emmling at 10:07 AM on January 12, 2005