Overexposure - four vacation rolls

<p>All look about three stops overexposed. Velvia 50. Aperture priority setting.<br>

I set up the shots using the viewfinder and all looked normal. Used a shutter release cable on at least some, if not all. After seeing the results I checked the meter and ISO setting and made sure I had not set the bracketing up one, down one by accident. Looked at the lens shutter iris and it is closing in response to aperture changes and looks normal. The developer (TheDarkroom) records indicated they did not push and used E-6.<br>

Today I picked it up and the focusing screen was loose and could be seen as out of place through the viewfinder. Any way this might have interfered with all those shots if it was working loose?<br>

I had not used the camera for a couple of years and I am wondering if something might be hanging up and holding the iris open too long. I doubt that the shutter release cable is involved. I am hoping that the electronics have not gone haywire. I was using fresh batteries and everything sounded perfectly normal.<br>

Anyone have an idea what might be happening?<br>

Thanks.<br>

George<br>

361-232-7092</p>

<p>Camera?</p>

 

<p>Check your meter against a proven meter. </p>

<p>Sorry, Pentax 645 (manual).</p>

<p>Did test the meter against proven meter in another camera that did well at the same locations. </p>

<p>Sounds like a sticky shutter. </p>

It could be the shutter, as suggested above, or it

could be that the aperture blades in the lens are

slow to respond. Either way it sounds like the

camera needs a service. However I'd exercise the

camera by dry firing it a few dozen times first. Cameras that haven't been used in a while can get "sticky".

<p>Before using a camera that hasn't been used for two years you should test it, you wouldn't drive a car that hadn't been on the road for two years.</p>

<p>Rodeo and Les, would canned compressed air be wise as to the possibility of the shutter sticking?</p>

<p>Personally, I am not a big fan of compressed air. In the past I have found that it actually sprays out some solvent(?) or some sort of 'carrier'(?) or such that leaves spots. Who knows what that spotting might do long term to a lens coating, or how it might add new issues to, or alter, lubricants that are present.</p>

<p>I did spot up an old lens once with this stuff and regretted having used it. How various manufacturers may have different materials in these cans -- well, still a risk.</p>

<p>(Also - the pressure 'may' be damaging in the case where it might be used in the presence of, let's say, a different camera such as a 35mm where a cloth focal plane shutter may be implemented.)</p>

<p>You are better off getting proper service for your Pentax 645 rather than risk adding more issues. Just My Humble Opinion from past experience.</p>

Compressed "air" cans aren't really air. They're

butane or some other easily liquified gas. Ok for

blowing the dust off a computer keyboard, but

pretty useless and potentially damaging for

photographic equipment.

 

In any case a blast of gas isn't going to degrease a

shutter or aperture iris.

<blockquote>

<p>In any case a blast of gas isn't going to degrease a shutter or aperture iris.</p>

 

</blockquote>

<p>Some oils and greases are soluble in liquid butane, but yes, gas doesn't help much.</p>

<p>If you turn a butane can upside down, it will usually come out liquid, and takes a few seconds to evaporate. I don't know if that helps, any. </p>

<p>It seems more usual to use liquid lighter fluid, such as Ronsonol, for cleaning shutters.</p>

<p>Thank you all for the advice. These days a shop service/fix is almost as much as just getting a used body online. I had a lot of fun on the vacation with my new collection of vintage Nikons and all the Nikkors that i could never afford before. So I may just liquidate the 645 system since we don't make the big vacations very often any more. The Pentax 645 is a great system though! Thanks. again.</p>

What a pity! If your overexposure was consistent I would guess the light meter to be ok. Rather a slow shutter, if used in Aperture priority.

Maybe like mentioned before, give it some more exercise, might still work well with B&W film and negatives. Have you used it after you

noticed that the screen had become loose? I don't know how the metering works, but stray light through a loose screen might have

caused consistently wrong exposure.

<p>I know this is an old topic; but the problem could be the xrays at the airports. Did you fly to your vacation? The films (even though they are not fast) will get fogged when they go through the xrays multiple times. 120 film is wrapped in paper, so it might be more susceptible to fogging. Does the unexposed part of your negatives show fogging? I would try the camera with a fresh roll and see if you still get overexposure.</p>