Pre-rinse before development?

[ramiro_aceves]

Hi all,

A friend of mine told me that he has heard that a pre-rinse before

development is a good thing. Do you think is it true? I have never

seen that information in Kodak and Ilford datasheets. Thank you.

[donald_miller1]

Hello, I have always heard that it is a good idea. Albeit, I have not seen it in mfg data sheets either, that I can recall. The rationale that I have always heard is that it softens the emulsion and prepares it for a more consistant development. Since I have always used this in my system, I have no experience to judge against non presoaking. I exclusively develop sheet film today, but have used a presoak in roll film development some years ago. Hope this provides you some information for you to make an informed decision from. Good luck.

 

Regards,

 

Donald Miller

[greg_smith4]

I used to do it, and my school says we should. It can lower contrast. I stopped doing it and didn't really notice a difference. I don't do it any more just because it's easier not too.

[joseph_walsh2]

Yes, Donald is correct: The rationale is the wet, swollen emulsion will accept the developer more quickly and evenly.

 

I can see how this might be a useful technique with short, say under 6 minutes, developing times to reduce the chance of uneven development.

[trooper]

There were films with the back layer that required a pre-soak with wetted water (my senility mode had set in as I write this, but I believe they're called anti-halation layers). The old Efke formulation had them as I recall. I think it aids in tempering the equipment to a known temperature for additional control of this aspect, too. I must admit that I've done things both ways over the years and can't honestly say I can tell the difference. If my darkroom is extra chilly during winter use, I tend to do it just to minimize the temperature effect from the cold tanks when the developer goes in.

[gwilburn]

The main reason for a short pre-rinse is to try to eliminate any air bells from the film. Agitating well and tapping the bottom of the tank a few times during the pre-rinse coats the entire surface of the film in liquid. The theory is that the developer then covers the film surface better.

[uncle_ziba]

There is at least one product whose manufacturer specifically asks not to pre-soak before development.

[john_hicks___]

A brief, one-minute or so prerinse can solve problems with airbells in manual or rotary processing. There's no need to do it unless you have a problem it'll solve. A long prerinse can cause speed and contrast changes that vary together and separately and by film type; there's no "factor" that can be applied.

 

Jobo recommends a five-minute prerinse, stating that the prerinse allows a known-valid intermittent-agitation development time to be a good starting point for rotary agitation. Jobo says to not use a prerinse with Xtol simply because Kodak so nicely provided rotary-agitation development recommendations. You can certainly use a prerinse with Xtol but then Kodak's development recommendation may no longer be valid.

 

Ilford recommends against a prerinse on the basis that wetting agents are incorporated into the emulsion and a prerinse may randomly remove them, causing mottle and uneven development. I've never seen this with any prerinsed Ilford film, but then absence of evidence isn't evidence of absence.

 

The notion that a prerinse somehow magically "prepares the film for development" is imho a myth that's propagated from school photo instructor to school photo instructor without any basis in reality and should be allowed to sink to the bottom with the fixer.

 

To sum up, if you have a developing problem that a prerinse may solve then by all means go ahead and use a prerinse, but otoh don't use a solution in search of a problem.

[chris_eve]

<SNIP> ... but otoh don't use a solution in search of a problem.

 

I can empathise entirely with this viewpoint, but in this case, given the apparent random nature of air-bells, I think potential prevention is better than cure, even if you've never had an air-bell. I always use a pre-rinse at developer temperature, whether it is specifically recommended for or against by either the dev manufacturer or the film manufacturer, both with conventional b&w and C-41, and have not (yet) had any symptoms that I can attribute to doing so. OTOH, in the dim and distant past, when I occaisionally tried to rush things and skipped the pre-rinse, I sometimes ended up with less than perfect negatives, though this may have been due to other factors, like being in a rush ;-)

[chris_waller]

I used to get an occasional problem with uneven development and so I began to pre-soak. Since then I have never had a problem. I tested development times with and without pre-soak and found no measurable difference in the the contrast etc. of the negs. I give 2 minutes at 20 C (or whatever temperature you use).

[travis1]

do u warm up before u go for a jog? if so, pre soak it.;)

[james_chinn]

I use a JOBO and followed their recommendation for a presoak at the beginning. I still do a presoak but only for one minute. I have developed test sheets of the same subject matter both ways and never noticed a difference, but I still do it to maintain a consistent protocol.

[lex_jenkins]

Perhaps David Carper (of Ilford) or a technical support person from one of the other film manufacturers can comment, but my understanding is that films today are designed to eliminate any need for a presoak. In fact, presoaking may alter the results or produce inconsistencies.

 

I don't think I've presoaked a film since the early 1970s when I last worked with sheet film. I've never seen an "air bell" and don't think I'd recognize one if it rang in my ear.

 

Again, as usual, I'm inclined to defer to the makers of these materials. If they don't specifically recommend an alteration to procedure, such as presoaking, the step is probably pointless and possible harmful.

[m0002a]

Earlier today I as used a presoak on Pan F+. I have used presoak shortly after I started using 120 film in 1982. When I first starting developing 120 format, I noticed that my negatives had subtle streaks, presumably from the developer cascading through the reels in the tank. I never noticed a problem with 35mm film in the prior 15 years that I did not use a presoak. I have not noticed any adverse effects of using a presoak even though the manufacturers don't recommend it. They don�t recommend using distilled water with developer, but I do that also.

[doug_landrum]

I have processed in my small tank both ways. But I understand that a pre-soak is not recommended when using Xtol. I understand that Ilford recommends not to pre-soak their films. Since I mostly shoot with Delta 100 and HP5 Plus developed in Xtol these days, I do not pre-soak and get good, even results. My water source is very hard water and I have never seen a water bell. I was instructed to tap the tank on the counter after agitating to knock any bubbles off. That works for me.

[m0002a]

The problems I had without pre-soak had nothing to do with air bubbles. It had to do with uneven development caused by the developer cascading through the reels in an uneven manner as the tank filled up. Manufacturers may have changed their emulsions such that presoak is no longer necessary, but I don't think it does any harm. At this point all my development times are standardized using pre-soak, and I have no motivation to retest without a pre-soak.

[edward_zimmermann]

Pre-rinse is probably <em><u>not</u></em> a good idea for B&W film developer, especially in a hand inversion tank. Many B&W developers demand mininal and controlled agitiation and many contain wetting agents and calgon. While one could no doubt work around to modify one's agitiation and development process to produce good results using a pre-soak, there is little benefit is the first soak anyway and its best just left out.

<P>

What reason have we heard here?

<UL>

<LI>"<cite>softens the emulsion and prepares it

for a more consistant development</cite>".

<P>

If the development process is well designed without a pre-wet why would adding more lead to more consistancy? How does throwing water in and dumping it out, increase rather than decease connsistency?

<LI>"<cite> It can lower contrast.</cite>"

<P>

Sure, cause its increasing development time. You could just as well decrease development time and save the soak for your socks.

<LI>"<cite>wet, swollen emulsion will accept the developer more

quickly and evenly. </cite>"

<P>

And when you dump the developer onto the film it too gets wet. The wetting agents also help get a more consistent and quick coverage. Washing the film seems counterproductive to the utilization of this developer design.

<LI>"<cite> eliminate any air bells from the film.</cite>"

<P>

So can a simple knock!

<LI>or getting the temperature etc. etc. etc.

 

</UL>

<P>

There are materials and developers where a pre-soak does not only make sense but is of significance to the process--- for example, blasting off Remjet---- BUT there are mostly outside of the domain we are discussing here.

<P>

If following the procedures for the film and developer is not enough a ritual you could dance a nice Irish Jig or a Freylakhs.. it might not really make the development more consistent BUT you'll get some exercise and get into a good mood to feel better about the results...

[m0002a]

I guess that I don't understand the relationship between pre-soak and agitation, but maybe that's a limitation in my understanding. I don't think that anyone has adequately explained what harm a pre-soak does. The goal is to ensure even development, and if one achieves that end (with or without pre-soak) then it does not really matter which method is used.

[edward_zimmermann]

"<cite>I guess that I don't understand the relationship between pre-soak and agitation,</cite>"

<P>

In a nutshell, agitation is for some developers to control development by bringing more or less new chemicals to film.

<P>

"<cite>I don't think that anyone has adequately explained what harm a

pre-soak does.</cite>"

<P>

In most cases I might concur that most of the harm done is in the effort to do an extra step and in the additional time required. In some cases, however, which come to mind, such as extremely low contrast developers for microfilm, I can expect it to lead to less even negatives through less control-- which is highly demanded of the material.

<P>

"<cite>The goal is to ensure even development, and if one achieves that end (with or without pre-soak) then it does not really matter which method is used.</cite>"

<P>

But if one gets even development without.. they why bother?

<P>

As I've pointed out.. many developers contain wetting agents and calogon and even many modern films and papers have special treatments to support development. Washing these or watering the materials before development is contrary to their design and can at best do nothing positive other than work to undermine the process design.

[chris_waller]

Mark,

 

You seem to have had exactly the same problem that I had with 120 film. In areas of even tone, e.g a clear blue sky, subtle streaks would be noticeable. Pre-soaking solved it for me too.

[joe_lipka3]

Sheet film in trays, yes, roll film no. Two reasons for sheet film is to make the emulsion ready for developer (not much of an issue these days with thin emulsion films) and to keep the sheets from sticking together when they first hit the developer. It may not help, it may not hurt. Roll film, definitely not necessary. That is very thin film even when compared to sheet film.