Within frame light leaks - Minolta 800si

<p>Hi there,</p>

<p>I hope it's the right forum; I couldn't find a dedicated 35 mm forum so please, excuse, if I picked up the wrong

site.</p>

<p>I've just picked four rolls of B&W film that I left in local lab two days ago. The film was shot with Minolta 800si I

purchased few weeks ago.</p>

<p>I was quite dissapointed to see that most frames feature a light leak on the bottom of the frame; however, the film

base is clear throughout the whole film. What also striked me was that the frames that weren't taken in the bright

sunlight remain properly exposed with no light leaks and whatnot. Also there are no light leaks on the color print film

which I had developed in the same lab and on the film I had developed by myself.</p>

<p>The following link features some samples of what I've been talking about: <a href="http://grabun.com/tmp/

ll/">link</a>.</p>

<p>The question is: is it the camera, the development in the lab or something else? As I said, the film base isn't

fogged and remains clear so wouldn't say it's the detoriated foam. What is it then?</p>

A few factors that influnce this that are not mentioned:<br>

What speed are the films?<br>

What type of agation does the lab use on B&W film.<br>

What are the frame numbers intensity on the questione frames compaired to the rest of the roll?<p>

A light leak usually extends into the film edge, not just the image area. To test the camera, remove the lens, open

the shutter and lock on Bulb, go into a dark room and shine a mini mag or simular flashlight with fresh batteries set

to produce a spot at 2 inches into the lens opening and observe the back of the camera for any hint of light. Be sure

to aim the light into the supply and takeup film areas from the front of the camera. Now looking thru the lens opening

run the light along the edges of the back. Let your eyes adjust to the total darkness before starting. If the camera

has a leak it will most likely appear as a very faint yellow dot or streak. Close the shutter and open the camera back

then shine the light at the shutter from the front and observe at the open back. Anything brighter than the total

darkness of the room is a leak.

If I remember my optics correctly, the bottom of the image is really the top of your camera because the lens inverts the image.

Light leaks are elusive, and bright sunlight will certainly help make them appear on film, if the camera is prone to leak. One of my previous jobs at a major photo manufacturer was to determine if film and paper cartridge designs and materials were light-tight. I used strong sunlight and tested the cartridges/cassettes at various angles to the light itself. So it is typical, in my professional opinion, that you are much more likely to find light leaks when shooting outdoors on sunny days.

As Charles replied, the light leak (unintentional exposure; fog) should show outside the image frame and into the border markings. Can you scan and post the full frame including the sprocket holes all the way to the edge of the film? That would help confirm the diagnosis.

If you place the negatives end to end (or if they were not cut), then you should see the light leak fog across frame lines as well. You might see a repeat pattern of the diameter of the film on the take-up spool, meaning the fog happened on that side of the camera. Or it might be intermittent, as you mentioned, on the frames shot in sunlight - meaning that the fog might be coming from a bad foam seal near the frame area, or even through the lens if you have a faulty shutter.

<p>Hi there,</p>

<p>Being really determined not to send back the camera to previous owner, I went to the local camera repairman. He carefully examined the camera and said it is in beautiful shape, the shutter curtains are in excellent condition and really nothing's wrong with the camera. He suggested, however, that if the camera had been left unused for a long time the shutter could have become, erm, stale from the lack of better word. The other day, when I was exchanging emails with the previous camera owner, he said that the camera hadn't been used for the last two years. Regarding the fact that the next day exposures were perfectly OK, I guess the problem is solved. I hope to check the camera tomorrow's morning, in the dawn. Keep your fingers crossed.</p>

<p>Thanks for all the tips and hints, guys, they're deeply appreciated.</p>