Getting three goes from a test roll (35mm)

[harrygrey382]

Well, I've finally found something I can't answer by searching this incredibly detailed site.
I've just got 10 rolls of Adox CMS 20 from silverprint (nice shop), and I want to find my development time for the 20asa raiting. I've shot a test roll, and am wondering if I can cut it into three lengths (1/3 total length each) as best I can in the dark, and develop each of them with a different time? This would be to conserve film.
I'm thinking also, can I re-use the same developer (the special adotech stuff at 1+24) for the 3 1/3 lengths? I know this would end up in total the same as a full film, but would it be acting significantly weaker for the 2nd and 3rd test strips?
Thanks for any suggestions

 

[Scruff McGruff]

As long as you aren't calibrating something like stand development, which it doesn't sound like you are doing, you should be fine cutting the film into strips and using the same developer dilution as with full rolls (though I would wait for more experienced members to chime in first! ). I've been doing something similar to figure out a pesky film fog issue.

Dunno about your developer question though. I'm pretty new to this stuff and have only used my developer one-shot, so far.

 

[ic-racer]

I have found more developer activity when developing less than a whole roll. Keep this in mind if you are processing short lengths to determine a development time for a full roll.

 

[harrygrey382]

so I really should use a new batch of developer for each test strip?

 

[Christopher Walrath]

Since you're testing, test the partial development this one time at N, N-1, N-2. Find which works best for contrast and then you can use that for every succeeding time you develop a partial roll without having to guesstimate. This will give what you need to know in order to use the same developer. And at this rate you should see the affects of spent developer for at least 15 strips (read: safe guess), if not much more.

 

[GJA]

I would develop all three together at first, then remove one to the stop, continue with two, remove the second and continue with one etc.

Alternatively, you could progressively add them.

 

[harrygrey382]

Since you're testing, test the partial development this one time at N, N-1, N-2. Find which works best for contrast and then you can use that for every succeeding time you develop a partial roll without having to guesstimate. This will give what you need to know in order to use the same developer. And at this rate you should see the affects of spent developer for at least 15 strips (read: safe guess), if not much more.

I'm afraid you've lost me with the N notation - is this a time thing?

I would develop all three together at first, then remove one to the stop, continue with two, remove the second and continue with one etc.

Alternatively, you could progressively add them.

Now this is quite cunning. Adding them would b easier, it would save juggling stop, fix etc. - I can see a disaster there. Although then I wouldn't benefit from the fresh developer for the second strip. Also, my paterson tank only takes two spirals

 

[ic-racer]

For most reproducible results, do the test roll the exact same way you will do your 'picture' rolls. So, same tank, agitation, concentration, volume, temp and number of rolls of film. If your test only uses part of a roll, then fill up the rest of the roll with pictures. If you will normally be processing 12 rolls at once in a tank then you need to 'bootstrap' yourself to a goal development time, because, you would ideally process the test roll with 11 other 'picture' rolls.

I could look up a few examples, but off the top of my head have done a six-inch control strip (processed alone) which gave something like a 0.65 gamma, while the same control strip processed with 8 rolls of film gave it something like 0.55 gamma.

A logical way to proceed is to do your short strip tests to get a ballpark development time. Then fine tune from there.

What I do with 35mm is to expose my step wedge onto the part of a roll. Then when I load that roll up, I start shooting at frame 6.

 

[gainer]

What size tank do you have? How much working solution will you be mixing? Any rolls I know of these days would be 2.5 inches wide and the reels would be covered by 16 oz. I have a Pattersen tank that holds 3 reels of 120 film and takes a liter to fill. I think if that's about what you have, you're worrying too much IMO. The most damage to the developer would be from aeration due to pouring back and forth. Leave the developer in the tank and dip-and-drain the reels individually for the test periods. Drop each developed reel into a pot, tank or other appropriate vessel of fixer without rinsing. That's a long time in the dark, but you'll know your way around when you are done. You'll also see even the tiniest light leak.

 

[fschifano]

I have found more developer activity when developing less than a whole roll.

True, but only if you don't have enough developer for a full 80 square inches in the first place. With D-76 and XTOL, that works out to be about 150 ml. minimum for me. I've had good, but variable results using less stock solution. This is regardless of the dilution ratio used to make up the working strength solution. A roll of film with mostly high key images will need more developing agent than a roll that has mostly low key images. The 100 ml. minimum suggested by Kodak for these developers works as advertised for a roll consisting of "average brightness" (my quotes) scenes. With D-76, Kodak also recommends adding 10% to the development time when using the minimum amount of stock in a very small tank.

 

[ic-racer]

True, but only if you don't have enough developer for a full 80 square inches in the first place.

Since my tests with 8 films were conducted with the developer volume recommended by Kodak (28cc Tmax per 8x10) and Agfa (10cc Rodinal per 8x10) I think it is more related to the "equivalent processing volume" for a 6 inch strip not being enough to cover the film when on a reel in the tank. Therefore the smaller strip is in relatively more developer.

 

[Anscojohn]

Well, I've finally found something I can't answer by searching this incredibly detailed site.
I've just got 10 rolls of Adox CMS 20 from silverprint (nice shop), and I want to find my development time for the 20asa raiting. I've shot a test roll, and am wondering if I can cut it into three lengths (1/3 total length each) as best I can in the dark, and develop each of them with a different time? This would be to conserve film.
I'm thinking also, can I re-use the same developer (the special adotech stuff at 1+24) for the 3 1/3 lengths? I know this would end up in total the same as a full film, but would it be acting significantly weaker for the 2nd and 3rd test strips?
Thanks for any suggestions

*****
Yes and no. You can snip the film, to be sure; but use fresh developer for each test snippet in order to get consistent results. If you leave the leader out (or retrieve it) you can take out what you need for each test, so there is not need to do it all at one time. Good luck.

 

[pentaxuser]

What size tank do you have? How much working solution will you be mixing? Any rolls I know of these days would be 2.5 inches wide and the reels would be covered by 16 oz.

The OP is talking about 35mm whereas your reply seems to be about 120 rolls. Assuming your reply is aimed at 120 rolls and not 35mm what differences would there be in your advice on 35mm?

pentaxuser

 

[gainer]

The OP is talking about 35mm whereas your reply seems to be about 120 rolls. Assuming your reply is aimed at 120 rolls and not 35mm what differences would there be in your advice on 35mm?

pentaxuser

The total area of a 120 roll is the same (close enough for government work) as that of a 35 mm roll. That is what counts.

 

[harrygrey382]

What size tank do you have? How much working solution will you be mixing? Any rolls I know of these days would be 2.5 inches wide and the reels would be covered by 16 oz. I have a Pattersen tank that holds 3 reels of 120 film and takes a liter to fill. I think if that's about what you have, you're worrying too much IMO. The most damage to the developer would be from aeration due to pouring back and forth. Leave the developer in the tank and dip-and-drain the reels individually for the test periods. Drop each developed reel into a pot, tank or other appropriate vessel of fixer without rinsing. That's a long time in the dark, but you'll know your way around when you are done. You'll also see even the tiniest light leak.

The total area of a 120 roll is the same (close enough for government work) as that of a 35 mm roll. That is what counts.

I use a Paterson system 4 that takes a max of two rolls. It states 10oz per roll. 10oz covers one roll (I guess haven't checked), so we're talking 290ml for the tank. 20oz/580ml in the tank would defeat my stingy aim of only using one shot of developer. Do you still think what you said aboutthe pouring having the most effect? I like the idea of doing it that way - after dropping the first one in fixer I could turn the light on while agitating could I?

*****
Yes and no. You can snip the film, to be sure; but use fresh developer for each test snippet in order to get consistent results. If you leave the leader out (or retrieve it) you can take out what you need for each test, so there is not need to do it all at one time. Good luck.

OK, so this contradicts gainer... I guess it's safer though. What about developing two together, and pulling one out in the dark early and dumping it in stop, then agitagite the other, then fix the first etc.?

I'm waiting for some IPA to come in for my final rinse before I do more developing to try and solve the mysterious dirty neg saga that's making me pull my hair out, see why people would go digital and just put me in a constant bad mood. I may start another thread on that subject though later (yes I've searched big time, and followed all advice)

 

[pentaxuser]

I'm waiting for some IPA to come in for my final rinse before I do more developing

As you're in Norwich would the IPA be Greene King?

pentaxuser

 

[harrygrey382]

As you're in Norwich would the IPA be Greene King?

pentaxuser

Did have one of those a couple of days a go (normally more of a plain pale ale fan myself). In this case I'm talking about iso-propyl alcohol though!