Multiple - Fragmented Exposures

So each fractional exposure creates + over exposure?
If I made eight exposures I would have to reduce my time by -3 stops?
 
Ian Grant said:
No, because of reciprocity failure, more like -2½ stops.

Ian
Click to expand...
Good idea to make the point of not forgetting reciprocity failure. Not sure if the attached method allows for reciprocity. Do you add the reciprocity first, ex.?
Metered exposure 2secs
Add 2s for reciprocity = 4s
4s 1 exposure
2s 2 exposures
1s 4 exp.
1/2s 8 exp
1/4s 16 exp.
how much would I reduce the exposure?
I found this
 

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Technically the attached is incorrect because it doesn't allow for reciprocity, but with 8 exposures and ½ a stop is not so critical, it may be close to a third..

I remember making this shot in the 1990s underground in a Manganese mine in North Wales.

1791471184640.png

We had torches and 4 hammerhead flash units. I had pre-focused my Wista & 65mm SA in daylight, and was shooting at f16 or f22.

For his image the area was painted with the 4 flash units, all set at full power, multiple flashes from each, I heard the others close their shutters way to early. I was the only person to get an image.

Somewhere I have a table for the extra exposure needed with multiple plash exposures, it was referring to multiple flash exposures to allow LF lenses to be stopped down mire in studio work. I remember it recommend 5 flashes when the calculation would be 4. it's exactly the sane with multiple daylight exposures.

Ian
 
Camerashy said:
Good idea to make the point of not forgetting reciprocity failure. Not sure if the attached method allows for reciprocity. Do you add the reciprocity first, ex.?
Metered exposure 2secs
Add 2s for reciprocity = 4s
4s 1 exposure
2s 2 exposures
1s 4 exp.
1/2s 8 exp
1/4s 16 exp.
how much would I reduce the exposure?
I found this
Click to expand...
When I went to Bristol (feb for martin parrs exhibition I shot a whole roll on my mamiya 7ii double exposure. What I found is if you have the sky in the scene the negative builds up density to the point where it starts losing detail. This happens I learnt when you layer one frame 16 times or above, I mostly do 16 and 32.

Last month or in July I did some tests near me shooting a roll like; normal, x2,x4,x8x16,x32. I learnt that the developer plays a big roll and also you have to reduce development when shooting 16 and above layers.

Once I’ve finished cooking I’ll transfer my pictures here to give a reference from my computer. I’m on phone atm.
 
Don't know why but its saying files are to big. ill try on the weekend.
 
I made a couple of experiments last week to see how best to make these type of image with the work I make, as I’d had it in my mind to do it with this subject for 6 months or so. Initially I was thinking about making them at dusk and using off camera flash, to give more light and freeze the movement of people and flags in the image. However this is a structure I am doing some heritage professional work on for the local council at the moment and wanted an image for the front page of a report, so thought I may as well try things out.

This is 5x7 FP4 with a 210mm Symmar-S 5.6 lens on a Sinar P, TTB Metol dev.

The first was 6 or 7 shots at 1/60th at F45. (both the minimum aperture and maximum shutter speed of the Sinar copal shutter) metered for an exposure of 1/15th
The second was 10 shots same exposure and this kind of looses the effect I was after, although these are quick scans and I look forward to a little more play in the darkroom.

I’ve wondered about using a red filter for an extra few stops to play with.
Thoughts and suggestions welcome and making better notes already on my list.

The Bridge of Remembrance Forum.jpg

The Bridge of Remembrance 2.jpg
 
Tim Holmes said:
I made a couple of experiments last week to see how best to make these type of image with the work I make, as I’d had it in my mind to do it with this subject for 6 months or so. Initially I was thinking about making them at dusk and using off camera flash, to give more light and freeze the movement of people and flags in the image. However this is a structure I am doing some heritage professional work on for the local council at the moment and wanted an image for the front page of a report, so thought I may as well try things out.

This is 5x7 FP4 with a 210mm Symmar-S 5.6 lens on a Sinar P, TTB Metol dev.

The first was 6 or 7 shots at 1/60th at F45. (both the minimum aperture and maximum shutter speed of the Sinar copal shutter) metered for an exposure of 1/15th
The second was 10 shots same exposure and this kind of looses the effect I was after, although these are quick scans and I look forward to a little more play in the darkroom.

I’ve wondered about using a red filter for an extra few stops to play with.
Thoughts and suggestions welcome and making better notes already on my list.

View attachment 6700

View attachment 6699
Click to expand...
I like both but I would do a square crop and get rid of the post on the left.
 
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