Help With Fogging Problem

[jim_poehling1]

I am encountering a very frustrating problem, primarily with outdoor exposures. Dark splotches/shadows appear from the corners of the negative (usually lower left)extending towards the center. Sometimes these shadows obscure the negative altogether. I don't think it is related to processing (using a Jobo expert drum), because some negatives (even some outdoor exposures) in the same batch come out fine. I am using t-max 100. Is this flare? I have tried to shade the lens with the slide, and it doesn't seem to help. Camera is a new Toyo Field. I am pretty sure I am loading the holders OK, but I am at a loss to solve this problem. Do I need a compendium hood? Any suggestions would be appreciated. Thanks.

[jeff_white1]

I experienced a similar problem when my Zone VI camera was new. At

first I had no problems because I wasn't use to using the bale back,

so I would insert the film holder in the "normal" way. Once I sarted

using the bale back when inserting, many of my exposures had a light

fog as you described. For me if I opened the back and put the film

holder in place and then closed the back, the film holder would not

seat itself properly. You might look to see if the film holder is in

the correct position when it has been inserted.

[pat_j._krentz_29_palms__ca]

Jeff's answer sounds good to me. Pat

[marv_thompson]

The improperly seated holder theory souds very plausible, I have been

there done that, and there are techniques that work well to be sure

that the holder is seated correctly. With a bail, insert the holder

and as you release the bail, wiggle the holder ever so slightly in

and out. This will show you whee the proper position is for the

holder, it will catch in the correct spot and be very snug. With a

tradional back inseting all of the way and then pulling gently back

out on the holder shows when it is seated.

 

<p>

 

How do you remove the dark slide? Be sure to pull straight out from

the holder, and when replacing the slide push it straight in. If you

pull back on the dark slide, towards yourself, it can unseat the

holder form the back of the camera. You might also remember to place

a thumb, your left, in the center of the ground glass while resting

you fingers on the top of the camera. Apply a slight amount of

pressure with the thumb while removing the dark slide, this helps to

ensure that the holder remains in place.

 

<p>

 

It is not a bad idea to try and cover the back, even of a brand new

camera, of the camera with you dark cloth in bright light, especially

when removing and replacing the dark slide. I try to at hold the

slide so that it casts a shadow on the light trap end during the time

tht the dark slide is removed.

 

<p>

 

Lastly, have you checked the holders themselves? Are they all new or

are some or all used? Mark the holders and make careful note of which

negative is in which holder. Then when processing, if there are

defects, you can trace it to the possible "bad" holder.

 

<p>

 

All in all these types of negative defects can be the most difficult

to detect and correct, and can crop up at any time and for no

apparent reason. Care and patience will make most of them go away!

[james___]

Also make sure that the bellows is attached properly to the front and

back standards. It is so often overlooked and I have seen it more than

once. That goes for the locking slides on the ground glass also. james

[tony_brent]

You might also check when loading your holders that you have the film

all the way up into the guides, so that it rests inside the slight

raised area at the open end of the holder where the end flap seats. If

it is down where the end of the film is between this raised area and

the flap, it can keep the end of the holder open just a bit. That

might be enough on a bright day. Try loading one with the lights on to

see just how the film has to go.

[brian_c._ellis]

It certainly sounds like a light leak. If the dark areas are at the

bottom of the negative, this means that the light is coming in through

the top of the holder since the image is reversed on the

negative. The leak could be caused by any of the tings that others

have suggested. I would just like to second the suggestion that you

keep the holder covered by the darkcloth for the entire time it is in

the camera. When I first got into large format I had similar problems.

I was putting the holder in the camera and it sometimes would sit

there for five or ten minutes while I went through all the other large

format gyrations. Even with the dark slide in the holder, this can

cause light leaks particularly if the camera is in sun light. I now

cover the top of the holder with my dark cloth as soon as the holder

is placed in the camera and I leave it there until the photograph has

been made. When pulling and replacing the dark slide I keep the

darkcloth in my hand and grasp the slide with the dark cloth over the

holder. Since I started doing this I've had no light leaks.

[pat_j._krentz_29_palms__ca]

Jim, a cheap way to test your holders is to cut some enlarging paper

and put that in your holders and set them under a bright light for 3

to 5 minutes and then develope, if their are leaks it will show and it

is cheaper than using film to find the leaks, you can do the same when

checking for leaks in the bellows. The other thing you can do with

paper in the holders is make paper negs, a lot of fun. Pat