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ruediger
24th June 2011, 10:35 AM
... When you have time perhaps you could tell us more about the negative enlargement process you use.Sure.

For kallitypes I enlarge the negative on Arista APHS II film which after some flashing is developed in dilute print developer (Wolfgang Moerschs Eco 1+25). After stopping the development in a stop bath the lights are turned on. The positive should look very dense, usually the first time you get it right at this point you think that you must have overexposed by several stops. Then after a short wash the positive is bleached in a dichromate bleach, washed, soaked in sodium sulfite and then developed again which gives the negative. A pretty straight forward process and not as dust prone as processes where a contact copy is involved.

Since Arista APHS II is now gone I will switch over to some Wephota ortho film very similar to the Arista.

For the kallitype I coated a sheet of Arches Platine with a mix of 10% silver nitrate and 20% ferric oxalate and some contrast control. After exposure it is developed in 20% sodium citrate for about 4 minutes, then after a short wash it is cleared for 5 minutes in 3% citric acid, washed again and then fixed in a weak alkaline fixer then the final wash for 30 minutes. Usually I do a toning in Wolfgang Moerschs carbon toner which gives a more neutral image tone.

Cheers
Ruediger

ruediger
29th June 2011, 02:47 PM
OK, I found the resource on the net which I follow when doing enlarged negatives. I think this is a well known resource, but anyway: Ed Buffaloe: Less is More - Negatives by Reversal (http://unblinkingeye.com/Articles/NbyR/nbyr.html) on unblinkingeye.com

Cheers
Ruediger

Barry
30th June 2011, 05:16 PM
A long time ago I was shown how to do this by Liam Lawless and agree it works well. Unfortunately Liam seems to have disappeared from the photographic scene :(

cliveh
30th June 2011, 07:17 PM
For kallitypes I enlarge the negative on Arista APHS II film which after some flashing is developed in dilute print developer (Wolfgang Moerschs Eco 1+25). After stopping the development in a stop bath the lights are turned on. The positive should look very dense, usually the first time you get it right at this point you think that you must have overexposed by several stops. Then after a short wash the positive is bleached in a dichromate bleach, washed, soaked in sodium sulfite and then developed again which gives the negative. A pretty straight forward process and not as dust prone as processes where a contact copy is involved.

I donít know if this is of any help but if photographing with alternative processes in mind, I sometimes work direct from colour slides, thus negating the need for an intermediate positive.

ruediger
30th June 2011, 08:07 PM
I donít know if this is of any help but if photographing with alternative processes in mind, I sometimes work direct from colour slides, thus negating the need for an intermediate positive.Interesting, I never thought about that. But working with b&w film gives me more control over contrast and I can use the original negative for a normal print too. It took me a few enlarged negatives to get the contrast and density right, but now it is kind of second nature.

Cheers
Ruediger

Dave miller
1st July 2011, 07:14 AM
I read somewhere about using xray film for this sort of process, has anyone here any experience of that?

Akki14
2nd August 2011, 09:49 PM
X-ray film seems hard to obtain as least in my limited attempts to figure out how to buy some :confused:

I also use APHS but I heard recently that they stopped selling this at freestyle photo :( And I can't find it on their website anymore so it might be true. It was really nice stuff because, to me, it was no different to work with than paper besides being more careful about dim safelights. It printed about the same times as paper etc.

I've used Maco "Genius" ortho film and didn't find it similar to APHS but maybe the Wephota is different. Genius ortho film seemed to be so sensitive to safe light that i had to do without one.

cliveh
2nd August 2011, 10:19 PM
X-ray film seems hard to obtain as least in my limited attempts to figure out how to buy some :confused:

I also use APHS but I heard recently that they stopped selling this at freestyle photo :( And I can't find it on their website anymore so it might be true. It was really nice stuff because, to me, it was no different to work with than paper besides being more careful about dim safelights. It printed about the same times as paper etc.

I've used Maco "Genius" ortho film and didn't find it similar to APHS but maybe the Wephota is different. Genius ortho film seemed to be so sensitive to safe light that i had to do without one.

Heather, I have experienced no problem with Genius ortho film to red safelights. Can you elaborate please?

Akki14
3rd August 2011, 03:46 PM
It'd fog up. Also it was far too sensitive in comparison to APHS for negative copying.