Water stop

[csaunders]

Hi all,

Does anyone have any information about the 'official' technique when using water as a stop bath when developing in a Paterson 35mm tank?

Is it fill/invert/empty three times or something like that?

Thanks,
Christian

 

[Roger Hicks]

It's not really a stop, more of a way of washing the tank and (slightly) prolonging the life of the fixer.

There is little point in washing more than once -- indeed, the shorter the wash, within reason, the better, as you are not allowing the developer to keep on acting in an attenuated fashion. Agitation is utterly uncritical. A few seconds (15 to 30 -- doesn't matter as long as you're consistent) of sloshing around (inversions or rotations) is all you need.

Cheers,

Roger

 

[P C Headland]

Nothing "official", but I've been using a water stop for some time. I fill the tank, invert for 60 seconds, then dump the water. It has worked well enough for me over the past few years.

I use Rodinal 1+100 or PC-TEA 1+50 for the developer - both having typical development times of 10 minutes or more. With a shorter development time and/or more aggressive developer, the technique I use may not be appropriate.

 

[ZorkiKat]

Technically speaking, water cannot be a stop bath since it does not really neutralise the developer. Stop bath has to be acidic to really arrest the action of developer and stop it completely.

Water will just rinse the developer off. Fill and dump cycles of three or more times takes the developer out retained by the reel, tank, and film itself. Each fill and dump takes away part of this leaving a small part behind. More fill and dumps leaves less and less, making the environment inside the tank more friendly for the fixer.

How many times you do this depends on the developer you use. Dilute developers tend to be easier to wash off than highly alkaline more concentrated ones. For example, if you are using one of the carbonate Metol Hydroquinone "universal" developers like D72 (if you have reason to use it all!), you'd need to rinse more thoroughly than if you use Microdol 1+3 or D76 1+3.

The use of water rinse instead of stop makes it imperative to agitate the film in the fixer for the first 30 seconds or even full minute. This ensures that the acid in the fixer neutralises the developer fully and leaves no alkalinity to make it totally stop. Some active developer retained in the emulsion, even when the film is in the fixer can continue to develop where it's retained and create uneven densities in the negative.

 

[csaunders]

Thanks for the replies.

I am using D-76 1+1 and Hypam fixer one-shot, so I'm not sure where this fits in the strength/acidity ratings...

So it seems that I am not stopping development, simply emptying/rinsing the tank in preparation for the fixer... and since I am using the fixer as one-shot this should be fine.

Will I need to shorten my dev time or increase my fixing time to compensate? I don't want my negs to change or deteriorate over time!

Thanks,
Christian

 

[ZorkiKat]

Thanks for the replies.

I am using D-76 1+1 and Hypam fixer one-shot, so I'm not sure where this fits in the strength/acidity ratings...

So it seems that I am not stopping development, simply emptying/rinsing the tank in preparation for the fixer... and since I am using the fixer as one-shot this should be fine.

Will I need to shorten my dev time or increase my fixing time to compensate? I don't want my negs to change or deteriorate over time!

Thanks,
Christian

Nothing to change in the routines/schedules.

D76 1+1 is not that alkaline so it will rinse off easily. However, make sure you agitate thoroughly for the first minute (continuous would more like it) in the fixer to make sure the developer is stopped by the acid, and that fixing starts simultaneously on the entire film's surface.

Not using a stop bath will not cause your negatives to bad....bad (final) washing will.

 

[csaunders]

Nothing to change in the routines/schedules.

D76 1+1 is not that alkaline so it will rinse off easily. However, make sure you agitate thoroughly for the first minute (continuous would more like it) in the fixer to make sure the developer is stopped by the acid, and that fixing starts simultaneously on the entire film's surface.

Not using a stop bath will not cause your negatives to bad....bad (final) washing will.

Thanks!!!

I have the Paterson force film washer and I'll be washing VERY thoroughly!