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tonyowen
1-Jul-2019, 06:09
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Attached are three paper-negative images
The first and third are as developed
The second is the first image inverted .
There is a gross 'shadowing' that I think is due to having my Paterson red safelight too close.
1] is my assumption correct?
2] is the shadowing' pre or post exposure?
3] what else could cause the problem?

Regards

Tony

jp
1-Jul-2019, 08:08
The black bleed at the bottom of the image could be due to weak stop and fixer... You turned the light on before the fixer had time to do it's job.

tonyowen
1-Jul-2019, 08:33
You turned the light on before the fixer had time to do it's job.

Developed in jobo 2500 tank plus 2509 reel - times as recommended by Ilford

regards
Tony

Jim Noel
1-Jul-2019, 10:57
Over-used fix?

tonyowen
1-Jul-2019, 12:42
Over-used fix?

brand new one-shot, out of concentrate container bought less than a month ago, 1:9 mix. processing time 2 minutes as per Ilford instructions.

Regards
Tony

Doremus Scudder
1-Jul-2019, 12:53
First, you've got some pretty bad vignetting going on, but I'm sure you realize this.

The fogging and the density at the bottom of the first image are likely caused by a light strike. You'll have to determine where in your workflow it most likely came from. Check loading and unloading, safelight, and if your camera is light-tight (bellows, etc.). Often, a negative gets light struck when we inadvertently pull the back away from the camera body when pulling or re-inserting the darkslide. Refine your technique here.

You could load, unload and process in total darkness to eliminate the safelight as a culprit. Google on Kodak safelight test pdf to find the Kodak tech sheet that describes the safelight test.

FWIW, the center of the third image looks like it could make a print with proper contrast.

Best,

Doremus

Winger
1-Jul-2019, 20:21
The straight-edged area at the bottom is because the dark slide wasn't pulled all the way (top is bottom). The area with some exposure on the left of it is because the exposure was too much and it bled under the dark slide. The curved areas at the top are vignetting because the lens wasn't centered and/or it doesn't quite cover the format.

tonyowen
2-Jul-2019, 06:10
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First, you've got some pretty bad vignetting going on, but I'm sure you realize this. Best, Doremus


The curved areas at the top are vignetting because the lens wasn't centered and/or it doesn't quite cover the format.

Thank you both. Four images are attached. The first two show digital images of the gg with no obvious heavy vignetting, as inferred from the images on my posting #1.
The last two show my lens setup. The 180mm lens has a maximum aperture of f5.6 giving as 'stop' of 32.14mm. The Ilex 3 shutter has a maximum iris diameter of 34.6mm [1.362 inches according to spec.] The distance from the lens iris to the shutter iris is about 50mm, the lens iris is fully open. The shutter iris is set as per the reading with my light meter and the chosen speed.
My 'lens-shutter holder' is reasonably centred.
The lens more than covers the 4x5 frame with plenty of extra movements
The images I'm taking are at f16 or f22.
I wondered if the vignetting was caused by tilt of the front and rear frames, but was unable to get that effect by severe tilting.

Regards
Tony

Jim Jones
2-Jul-2019, 06:40
That combination of lens and front shutter would cause vignetting. In addition to vignetting, using a diaphragm located at the wrong position along the optical axis can cause a lack of sharpness.

cowanw
2-Jul-2019, 07:58
Are you setting the F16 or F22 on the shutter or the lens? Are your GG images at max aperture?

tonyowen
2-Jul-2019, 11:50
Are you setting the F16 or F22 on the shutter or the lens? Are your GG images at max aperture?

The shutter - apertures determined by measurement of 'apparent diameter'. The gg images were at the full f5.6 aperture.

regards

Tony

Dan Fromm
2-Jul-2019, 12:16
The shutter - apertures determined by measurement of 'apparent diameter'. The gg images were at the full f5.6 aperture.

regards

Tony

Wrong. When a barrel lens is in front of or behind a shutter, set the shutter's diaphragm wide open and use the barrel's diaphragm to control depth-of-field and (partially, shutter speed matters too) exposure.

cowanw
2-Jul-2019, 12:49
I would imagine that closing the shutter out front of the lens would cause vignetting; there are purpose made tools for that from years back in various shapes, such as Hi tech filter holders but they are so old I cant find any on the internet. As Dan implies the shutter f stop will not alter DOF as expected.

Cor
5-Jul-2019, 04:01
If I understand your lens set up correctly: after you close your shutter, some light can still enter your lens, thus causing weird effects. Only when you push in your darkslide no more light can hit the paper.

best,

Cor

tonyowen
5-Jul-2019, 08:23
If I understand your lens set up correctly: after you close your shutter, some light can still enter your lens, thus causing weird effects. Only when you push in your darkslide no more light can hit the paper. best, Cor

correct, the top and bottom of my 'holder' would allows some light to hit a portion of the extreme edge of the lens' shape. I'm surprised at the magnitude of this 'contamination'.

I can easily cover those spaces and see what happens.

regards
Tony

Dan Fromm
5-Jul-2019, 09:32
Ah! So what looks like a gap is a gap. Unwise.

Tony, you need to minimize the distance between the lens and the shutter.