Semi Stand Development: D-76 1+7 ratio verification for 4x5

peter k. · Nov 14, 2023

Kodak recommends 2oz of D-76 for each sheet of film, so the ratio mix should be 2+14=16oz, for one sheet of 4x5?

Background:
Ok been experimenting with semi stand development, shooting one sheet of MF film and developing that one sheet in a home made daylight tank with a mix of 1 (oz) +7, for about a dozen or so images. Developed for one hour with one inversion at 30 minutes and the images came out extremely well in my opinion.

So a couple of days ago we tried to develop one 4x5, and it seemed to be undeveloped or underexposed.
Hmmm so we tried again yesterday, ... with the same mix of 2+14 for the two MF images, and they also looked the same.
Undeveloped or underexposed.
Soooo do we have the development ratio correct or are we off in our exposure setting again?

Thanks p.

koraks · Nov 14, 2023

peter k. said:
with the same mix of 2+14

Did you use the same batch of working strength chemistry for these consecutive experiments, or freshly mixed & used one shot?

peter k. · Nov 14, 2023

koraks said:
Did you use the same batch of working strength chemistry for these consecutive experiments, or freshly mixed & used one shot?

Sorry for he confusion ... the same mix ratio, ... but freshly mixed and used one shot.

Dustin McAmera · Nov 14, 2023

The only thing that occurs to me is that if you're using the same tank for both cases, then with one sheet of medium-format film (is this 2¼x3¼ inch?) there would be a large air-space in the tank; I wonder if filling the tank for the 4x5-inch sheet reduced the effectiveness of your half-time inversion. I'm not convinced, but it seemed worth saying...

peter k. · Nov 14, 2023

Yes its 2x3 sheet film, and no we did not use the same tank.
We put together another new day light tank out of 2" ABS that will hold about 24oz of fluid and the area that the 4x5 goes into is about 6" long.

pentaxuser · Nov 14, 2023

If everything was the same then I'm stumped So the D76 does an OK job on a MF film but doesn't on a 4x5 with all other things being seemingly equal?

A real puzzler. The D76 doesn't know what kind of a film it is developing so should do an equally good job on both

The only thing that has changed as far as I can see is the camera so do we need to look at that aspect instead?

pentaxuser

MattKing · Nov 14, 2023

peter k. said:
Kodak recommends 2oz of D-76 for each sheet of film, so the ratio mix should be 2+14=16oz, for one sheet of 4x5?

Just to clarify where you get the 2oz figure from.
From the datasheet - j78 - I read Kodak as recommending a capacity of 16 8x10 sheets per gallon, or 8 oz per 8x10.
Which itself would equate to 2 oz per 4x5 sheet.
However - those capacity recommendations are not based on highly dilute, reduced agitation workflows.
It seems quite possible that those sort of workflows vary the available capacity of D-76.

pentaxuser · Nov 14, 2023

MattKing said:
However - those capacity recommendations are not based on highly dilute, reduced agitation workflows.
It seems quite possible that those sort of workflows vary the available capacity of D-76.

Can I ask why this would make an adverse difference to a sheet of 4x5 but not to an MF film. Matt?

pentaxuser

peter k. · Nov 14, 2023

pentaxuser said:
If everything was the same then I'm stumped So the D76 does an OK job on a MF film but doesn't on a 4x5 with all other things being seemingly equal?

No, everything was not the same.

The mix for MF, because it is a little less than half the size of a 4x5 was 1 oz of dev + 7 oz of water and all came out well.
The mix for the 4x5, ... recommended by Kodak, ... was 2oz of dev +14 oz of water and did not seem to come out well.

MattKing · Nov 14, 2023

peter k. said:
No, everything was not the same.

The mix for MF, because it is a little less than half the size of a 4x5 was 1 oz of dev + 7 oz of water and all came out well.
The mix for the 4x5, ... recommended by Kodak, ... was 2oz of dev +14 oz of water and did not seem to come out well.

It is approximately the same amount of D-76 per square inch of film.
BUT ....
The film is most likely on different substrate - and the substrate does matter.
And the fluid flow that happens in a tank - including when working a reduced agitation workflow - would likely be very, very different.
The potentials for extreme localized developer exhaustion could very well be very different.

peter k. · Nov 14, 2023

MattKing said:
It seems quite possible that those sort of workflows vary the available capacity of D-76.

Absolutely, and Kodak does not recommend any development, with D-76 past 1+1, but others like myself has have success, but it seems strange to me, that a dilution of 1+7 worked well with MF and doubling the solution for a 4x5 doesn't.

We were hoping for those who do semi stand that they could clarify that perhaps what direction we should experiment with.

Less time perhaps, or same time with a stronger dilution ratio mix.
As one can tell we need some guidance.

peter k. · Nov 14, 2023

MattKing said:
BUT ....
The film is most likely on different substrate - and the substrate does matter.

MF was cut from the 4x5 Arista 200 so there the same

MattKing said:
And the fluid flow that happens in a tank - including when working a reduced agitation workflow - would likely be very, very different.

Hmmm, the only time of fluid flow is the first two minutes of agitation, and the 30 mid dev inversion.
The tanks are both very similar, for the MF its 1.5" black ABS, for the 4x5 its 2" black ABS a little fatter and taller than the MF daylight tank to take the extra volume of developer for semi stand, as we also develop a 4x5 in the same MF tank, but need to put a mesh spacer behind, to allow the dev and fixer space to do their job on the back side of the image.

So its hard for me to believe that the development process would be that very different.

Hahaha ah ... But then my experience in doing semi stand is very, very little as we have just begun.

MattKing · Nov 14, 2023

peter k. said:
Hmmm, the only time of fluid flow is the first two minutes of agitation, and the 30 mid dev inversion.

This is not actually correct.
The fluid - or at least some of it - is actually moving throughout, because the development process is an active and physical process.
That is why we have problems with bromide drag.
The movements are small, but they happen.

peter k. · Nov 14, 2023

MattKing said:
The fluid - or at least some of it - is actually moving throughout, because the development process is an active and physical process.

Ahhh ... getting educated.
So the somewhat narrower 1.5" tank, would tend to keep the dev closer to the emulsion

MattKing said:
That is why we have problems with bromide drag.

Haven't seen any yet, as the edges of the film are against the interior of the tube, and the bottom of the sheet is away from touching the plug at the bottom.

Hmmm so time for more experimental development internally, ... as well as with film.

MattKing · Nov 14, 2023

peter k. said:
Ahhh ... getting educated.
So the somewhat narrower 1.5" tank, would tend to keep the dev closer to the emulsion

I'm not sure you can support any particular conclusion based on your results - other than that all the differences in geometry and materials can make a difference!

MattKing · Nov 14, 2023

And as for the bromide drag reference, I only made it because it is an example of something that happens because the fluids do move, even in a stationary tank.

Semi Stand Development: D-76 1+7 ratio verification for 4x5

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