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View Full Version : Any real advantage to pre-soaking HP5 to remove the anti-halation layer



stradibarrius
4-Feb-2013, 17:20
I am curious if there is an advantage to pre-soaking HP5 to be developed in Rodinal???

Robert Kalman
4-Feb-2013, 17:58
Not sure about HP5 specifically, but I always pre-soak my Tri-x because I believe that the developer then spreads more evenly across the film when immersed into the developer.

Bill McMannis
4-Feb-2013, 20:29
As Robert says, pre-soaking Tri-X (and TMax) makes a huge difference. While I have not shot HP5 if or when I do, I will presoak.

Eric Rose
4-Feb-2013, 20:41
Yes you must pre-soak! If you don't you will become a darkroom outcast. No one will want to play with anymore. Seriously I have done it both ways and have not seen any real difference in neg quality. If I plan on reusing the developer I will pre-soak so as to not muck up the soup.

rich815
4-Feb-2013, 20:46
Supposedly Ilford's data sheets say: "A pre-rinse is not recommended as it can lead to uneven processing."

And some people say its best to pre-soak or you'll get uneven processing.

Both are probably right.

rich815
4-Feb-2013, 20:48
Not sure about HP5 specifically, but I always pre-soak my Tri-x because I believe that the developer then spreads more evenly across the film when immersed into the developer.

Sounds like that makes sense. But then I've seen it said that not presoaking is better because then the dry film absorbs the developer better and faster than film that is already saturated with water.

I'm not trying to be flippant, these are all things I've read in the debate. To be honest I think either is fine as long as you're consistent.

Kevin Crisp
4-Feb-2013, 21:04
Makes a 'huge difference' how? And why? I know this as taken as gospel, but I don't understand why. And I've never pre-soaked any sheet film and I've never had uneven development either, despite short summer development times and tray development.

When I put a sheet of film into a tray, the entire sheet is submerged in a lot less than 2 seconds. Assuming 2 seconds, however, then the differential in development time across the sheet would be, in the context of a 5.5M development time, about 0.6%. So you have a theoretical increased density resulting from 0.6% more time in some random pattern across the sheet of film. You are never going to notice or detect that, any more than you would if you left half a sheet in the developer for just 2 seconds longer than the other half.

If the theory is that pre-wetting the emulsion makes it wet faster in the actual developer -- the most common explanation for a pre-soak -- I still don't follow the reasoning. There is going be a slight delay, wet or dry, in the developer reaching the emulsion in all places. There is the hair splitting tiny difference in developing time, again. You've got the same 'problem' you are trying to avoid. If it takes, let's say, a second or two for dry emulsion to be 'wet' by the developer, the process across the sheet is still going to be uneven in the very slightest way, true enough. But since the whole sheet is marching toward being wet and developed with the differential from place to place on the sheet being the same plus or minus one or two seconds, the difference is never going to be observed.

It is true, of course, that uneven development can be theoretically more likely to occur as development times get shorter and shorter. That 2 second delay in fully wetting the dry film and getting it on its way to an image because proportionally larger as the development time gets shorter. But even with a smoking short development time of 3 minutes, the delay is still only 1% of a difference, in a random pattern across the sheet of film.

If dry emulsion were resistant to wetting, and inconsistently so, so that the top of a sheet of film might take 10 seconds to get wet and get actively developing, while the bottom or sides would taken much shorter or longer, then I could understand how just getting the film wet in advance would even out the process. But dry emulsion doesn't interact with liquid that way. Put a drop of water on emulsion and wipe it away a second later. The film is wet. And it doesn't matter where on the sheet you put that drop, the film is going to get wet just as fast. And if instead of water that drop has developer in it, the chemical activity is going to start quickly.

cyrus
4-Feb-2013, 22:27
I've read that presoaking actually does NOT help the developer spread evenly, and instead makes it harder for the developer to soak into the emulsion since the preexisting water has to be displaced. I don't know if anyone has scientifically tested any of this (Ctein?) but I tend to presoak to rinse off any dust, but mainly because that's just how I was taught

Jason Greenberg Motamedi
4-Feb-2013, 22:32
I am a bit agnostic when it comes to prewash, but it does help bring your film and developing tank to temperature.

Michael Graves
5-Feb-2013, 05:58
I'm no scientist and I didn't do any controlled tests. But I do know that before I was told to start presoaking my film, I consistently had problems with consistency in even tones, such as skies and such. After I started presoaking, those problems are so infrequent that I can't remember the last time it happened. Go ahead and tell me the presoaking has nothing to do with it. But I'll keep doing it anyway.

Peter Lewin
5-Feb-2013, 06:13
My understanding is that the need for a pre-soak is developer dependent. The OP specifically asked about Rodinal, with which I have no experience. But for some developers, such as the PMK I use with my HP5+, the pre-soak is considered a requirement. Gordon Hutchings, in his Book of Pyro, states: "With stack development, film must be pre-soaked. Dry films placed in alkali developers will instantly stick together and if not separated immediately will fuse beyond recovery. Pre-soaking the film helps achieve more uniform development..." I mention this so readers will not assume that the pre-soak is unnecessary in all situations. (Usual "escape clause:" I simply follow Gordon's instructions for PMK, I haven't tried skipping the pre-soak to see what would happen.)

Steve Smith
5-Feb-2013, 06:34
I am a bit agnostic when it comes to prewash, but it does help bring your film and developing tank to temperature.

And pouring the pre-wash water out allows ambient temperature air in to displace it, cooling it again!


STEVE.

Kevin Crisp
5-Feb-2013, 08:30
I am saying that I've never done it and never had a problem. I am not saying it doesn't / can't make a difference in eveness. I just can't think of a reason physically or chemically for it to make a difference. I certainly agree that if you are using stack development and don't presoak the negatives can become glued together.

It wouldn't be hard to test this. Relatively short development time (under 4 minutes) two identically exposed negatives of a continuous tone placed around zone 8. One presoaked and one not. Measure 6 different spots chosen at random on both negatives and compare the deviation.

E. von Hoegh
5-Feb-2013, 08:38
I'm no scientist and I didn't do any controlled tests. But I do know that before I was told to start presoaking my film, I consistently had problems with consistency in even tones, such as skies and such. After I started presoaking, those problems are so infrequent that I can't remember the last time it happened. Go ahead and tell me the presoaking has nothing to do with it. But I'll keep doing it anyway.

Some films do not take to presoaking. Tech Pan, for instance. I presoak films in tanks for reasons stated above, but not sheets films in trays.

Cletus
5-Feb-2013, 08:47
I think it's developer dependent, and there are a few two-bath systems where presoaking will impede the process. Others claim to require it. I have always presoaked HP5 whether it was Rodinal, Pyrocat HD, WD2D or XTOL. With sheet film in trays, I set the soak water to the developer temp, so if I'm doing more than a couple sheets its less likely to swing the developer temp. For me, it also makes for a nice 'staging' area for the film getting ready to go into the develpor. Anything helps in the dark!

I also found, very early on in my "career" that failure to presoak makes it more difficult to wash out the purple tinted anti-halation dye in the final wash. This could be something else though, since I haven't had this issue in years.

I say presoaking offers more benefits than liabilities, so why not do it?

Kevin Crisp
5-Feb-2013, 09:07
I guess I'm not seeing what the 'more benefits' are. Won't the purple wash off just as much in the developer as in the pre-soak? Is there an advantage to having less purple used developer? It will wash off in the final wash if fixing was adequate. I don't see how adding an extra tray at the beginning of the process helps deal with a swing in developer temperature. The developer temperature is what it is, the following trays should be close to it and a few degrees difference in the follow on trays isn't going to make any difference with black and white. You've added an extra step handling wet film, which seems like a minus to me; what more staging is necessary than having a dry sheet of film in your hand as you unload the holder?

David R Munson
5-Feb-2013, 09:12
I've been pre-soaking my films since high school, but I can't claim to have any specific, well-defined reason why. I think I remember starting after reading one of the many, many books on photography I read back then (anything and everything I could get my hands on), and never stopped. I almost never have problems with uneven development, but in that regard presoaking may be like tiger repellant. Still, I do it and I'm not likely to give it up any time soon.

Drew Wiley
5-Feb-2013, 09:39
Presoaking does several important things. It swells the emulsion in advance so you aren't dealing with
that issue in the trays (sheets sticking together and delaying even developement). It helps the developer spread evenly from the start. And it preconditions the temperature (quite important with
short development times or critical work). The anthihalation layer is on the back of the film, so that
is not such a big issue, except with some films this can be stubborn to wash off completely and a head-start is useful. And yes, I have always done it with Tech Pan too. And I do it in hand tanks or drums
as well as trays, where it helps condition the internal temp - (very, very, important when using small
volumes of chem in large drums).

Kevin Crisp
5-Feb-2013, 10:02
Never had a problem with air bells after my first roll of 35 mm in a tank. It does prevent film sticking together, which can also be avoided by not piling up dry film. I don't understand (still) the preconditioning temperature argument. What does that mean? How is it related to even development with shorter development times?

Cletus
5-Feb-2013, 11:21
As far as unloading holders or emptying boxes of exposed film in my little space, it's easier for me to load the sheets into a tray of water - which happens to be my presoak tray at set temp - it makes it much easier for me to slide the whole stack into the developer and start the timer. It usually takes me at least a minute or three to unload everything to get ready for development and if I were going straight into the developer, my times would be all over the place.

Just one more reason why presoaking works for me. It's convenient and it makes sense to have the film I'm getting ready to process sitting in a tray of water, at the correct temp, ready to go into the developer all at the same time. YMMV.

IanG
5-Feb-2013, 11:59
Pre-soak and agitation prevents air bells on the film surface which screws up your development.

I did some testing a few years ago (4 or 5) and found that a pre-soak made no differeance to air-bells, they occur because the waters very hard, there are ways around them. I monitored every step of a process cycle with a Jobo tank and air-bells were present throughout.

My way of overcoming air-bells is a controlled addition of wetting agent (already dilute) because I mix frm scratch, most commercial developrs contain a sequestring agent and a touch of wetting agent anyway. Some films have a wetting agent in the emulsion.

Ian

henk@lf
5-Feb-2013, 12:05
I had problems with air bubbles with 4x5 Tri-x in HC 110 in a MOD54.
Presoak solved this.

Drew Wiley
5-Feb-2013, 12:12
We have soft water here and airbells are still an issue, more so with some films than others. Besides,
most developers are alkaline anyway. No difference even using distilled water. Many sheet films still
have a retouching texture on the back or something equivalent which inherently attracts air bubbles.
And all it takes is a tiny one. Proper film rotation or agitation is important, but I also feel prewetting
the film is a significant help.

rich815
5-Feb-2013, 12:15
Well, Im glad we finally put this issue to rest.

Cletus
5-Feb-2013, 13:40
Well, Im glad we finally put this issue to rest.

That's right, finally! Now we'll never have to have another conversation or argument on the "to soak or not to soak" issue. Thank goodness. :) :) :)

cosmicexplosion
5-Feb-2013, 13:56
I'm glad i don't 'have' to pre-soak any more after reading this thread. This has added hours and days to my life!

my only trepidation is that the developer is mixed with the filth that is washed away in pre-soak. practically it seems to make no difference. theoretically, however, would you add this gunk to your developer?

need to test two identical negs....

cyrus
5-Feb-2013, 15:45
For sheet film development using the shuffle mehtod, one benefit of presoaking is that there's no chance that the negs will stick together in the developer solution, which can be a real PITA

C. D. Keth
5-Feb-2013, 17:24
I process FP4 and Delta 100 without a presoak and can't see any reason to do otherwise.

David R Munson
5-Feb-2013, 18:41
It occurs to me that the greatest advantage to doing a presoak or not (in general terms only) may be the peace of mind it affords one. If you believe in one approach or the other, run with it.

Scott Walker
5-Feb-2013, 19:29
It occurs to me that the greatest advantage to doing a presoak or not (in general terms only) may be the peace of mind it affords one. If you believe in one approach or the other, run with it.

There is a tremendous amount of truth in that statement.

neil poulsen
5-Feb-2013, 19:37
Once upon a time (years ago), I was told by an Ilford Tech that the film has wetting agents making pre-soaking unnecessary. Sometimes I do; sometimes I don't.

Paul Hoyt
5-Feb-2013, 22:58
Before I moved to sheet film, I had problems with uneven development in continuous tone areas of 120 film. I read an article that recommended a presoak to solve that problem; and it did. When I moved up to LF format and sheet film, I read Ansel Adams discussion on how he developed sheet film and he used a presoak with sheet film. I have never developed my sheet film without using a presoak , TRI-X and FP4+ in HC-110, and my continuous tone areas have always been even.

Regarding the slight purple cast that can remain after processing, hang dry negative in an open window and the UV light will fade away the purple cast.

Ian Gordon Bilson
6-Feb-2013, 02:47
Well,I think it depends on the film,and also on the developer.
It is true that Ilford say p/s is un-needed,and that many developers have a surfactant component. So,no pre-soak for me,Unless...Foma,and other European films,if requested for Rodinal stand technique,really benefit from p/s.
This makes sense to me,because,over the course of an hour or two,diffusion into,and out of the emulsion,reaches a stabilised state.

Brian Ellis
6-Feb-2013, 09:52
I don't pre-soak HP5+ because Ilford says not to. I figure they know their film better than I do. With TMax 100 and 400 I've done it both ways, never seen a difference, so I stopped pre-soaking. Developer in all cases was D76 1-1. When I was using PMK I pre-soaked because that's what Gordon Hutchings said to do. But after a while I tried not pre-soaking it and saw no difference so I stopped pre-soaking even with PMK.

Vaughn
6-Feb-2013, 12:39
Using an Expert drum 3005 for 8x10's (usually FP4+) it just seems to make sense to me to pre-soak -- which I do for about 5 minutes. If I could see into the drum while it is turning to see how the liquids get moving over the sheets I would know for sure.

Drew Wiley
6-Feb-2013, 12:49
The time of the presoak can itself make a minor difference to development, so I always try to keep it
consistent too.

Lachlan 717
6-Feb-2013, 12:55
I do it for two reasons:

First, it is an inert "trigger" event. It focuses me on the processing I'm about to undertake without the danger of "diving in the deep end" of going straight to the Developer. That few minutes of presoaking is used to double check the chemicals, times, temp etc.

Second, I just dig the colour of the liquid that comes out of the tank!!

premortho
9-Feb-2013, 19:06
Before I moved to sheet film, I had problems with uneven development in continuous tone areas of 120 film. I read an article that recommended a presoak to solve that problem; and it did. When I moved up to LF format and sheet film, I read Ansel Adams discussion on how he developed sheet film and he used a presoak with sheet film. I have never developed my sheet film without using a presoak , TRI-X and FP4+ in HC-110, and my continuous tone areas have always been even.

I felt that the UV light idea had some potential benefit, so went to hang some developed film in the window. But when I opened the window, and felt that first jolt of sub-zero(fahrenheit) air, I decided to live withe the purple cast until summer! Regarding the slight purple cast that can remain after processing, hang dry negative in an open window and the UV light will fade away the purple cast.

premortho
9-Feb-2013, 19:09
I don't know what I did wrong to get my comment mixed in with Paul Hoyts' but I did it somehow.

Michael_4514
10-Feb-2013, 10:14
The original poster asked about HP-5 and Rodinal. Maybe he's given up on getting a straight answer on that subject. I've used that combination quite a bit and never presoaked. Works just fine for me.

I can't imagine what presoaking would do for this combination. Rodinal is best highly diluted with relatively long development times, so getting faster or smoother delivery of the developer to the film is hardly an issue. Rodinal is typically a one shot developer, so getting the antihalation layer runoff in the developer stock is not an issue. Rodinal is usually used at 20 degrees (centigrade), ie., room temperature, so "warming up" the film and tank is not a consideration.

Bill McMannis
10-Feb-2013, 19:05
I'm no scientist and I didn't do any controlled tests. But I do know that before I was told to start presoaking my film, I consistently had problems with consistency in even tones, such as skies and such. After I started presoaking, those problems are so infrequent that I can't remember the last time it happened. Go ahead and tell me the presoaking has nothing to do with it. But I'll keep doing it anyway.

While I do not do portraiture, I did see noticiable improvements with subtle shadow details in my archtectural work. Presoaking is the only way to go IMO.

Doremus Scudder
13-Feb-2013, 03:05
Pre-soaking is indispensable for those of us that develop sheet film by hand in trays in large batches in order to keep the film from sticking together in the developer. Other than that, I can see no real advantage to pre-soaking provided that the film is immersed quickly and evenly in the developer.

If that is not so easy to do (e.g., I never thought I could pour developer into a double 120 tank fast enough to guarantee that there was not a significant time lapse between the bottom of the bottom reel and the top of the top reel...) then a pre-soak seems a prudent measure to help ensure more even development, since it slows down the onset of developing a bit.

Similarly, if one re-uses developer, say in a replenishment scheme, then it might be a good idea to keep all that dissolved anti-halation dye out of the mix by removing it with a pre-soak.

I can't think of an instance where pre-soaking would cause problems. There is, of course, a slight difference in developing time with and without pre-soak.

Best,

Doremus

carbo73
14-Oct-2018, 12:27
I had this green stains in some of my first developed 4x5 using the "taco" method. In another forum they told me could be part of the anti-halation layer still present. I did not presoak these sheets, which were Foma Retropan 320. So maybe it's a good idea, at least in some cases.

183342

koraks
14-Oct-2018, 12:35
With a presoak, the rubber bands would still be in place with the taco method and your antihalation dyes would still not wash out completely. Just dump the negatives after processing them into a tray of water an let them soak for a while, the dyes will wash right out. At least the dyes used by Foma will. You can add a little washing soda to the water to facilitate the process; something like 2-4g per liter should be fine.

Peter Collins
14-Oct-2018, 16:36
I must be leading the "unexamined life." I used HP5+ and soak in distilled H2O for 3 minutes with agitation every 30sec. I suppose this will remove any dust, lint, etc., that got on the film, but it will be a benefit only with respect to the dust, lint, etc., that attached to the film after exposure.

But I feel a lot of satisfaction watching all that purple-blue water pouring out of my SP-445 tank.

Serge S
15-Oct-2018, 10:56
I always pre soaked as I was taught to do so.
When I started to process my sheet film I did pre soak one time & found issues with my dil.
I used a Jobo with DDX
It's best to test it for yourself, as different methods may or may not be affected by pre soaking or lack thereof.

Pere Casals
15-Oct-2018, 11:34
If you pre-soak , then pre-soak long enough beause if not it may lead to an uneven development, specially in a non rotary process.

"A pre-rinse is not recommended as it can lead to uneven processing." Iford says in the page 3 of datasheet : https://www.silverprint.co.uk/wp-content/uploads/2015/10/HP5-Plus.pdf

This is because pre-soaking removes surfactants from the emulsion that are included to ensure a even development.

DrTang
15-Oct-2018, 12:17
helps me with HP-4 in 8x10 only..which is weird

5x7... fine, but 8x10 has weird white 'clouds' occasionally that never happen when I remember to pre-soak... and they never appear on 5x7 even when processed together with the 8x10

Steven Ruttenberg
15-Oct-2018, 12:52
Well, one explanation I read says that presoak at development temperature allows film to swell to max size for that temp and bring film to developing temp as well. This way, the film can accept max amount of developer more quickly. I know you need it it for color neg and slide film. I do it with 2-bath Pyro a well and Tmax developer. Always done it no problems for me.

And it's cool watching the Easter egg die water pour out.

carbo73
15-Oct-2018, 13:42
If you pre-soak , then pre-soak long enough beause if not it may lead to an uneven development, specially in a non rotary process.

"A pre-rinse is not recommended as it can lead to uneven processing." Iford says in the page 3 of datasheet : https://www.silverprint.co.uk/wp-content/uploads/2015/10/HP5-Plus.pdf

This is because pre-soaking removes surfactants from the emulsion that are included to ensure a even development.

Thanks for the advise. Seems wise. Maybe better with a longer final wash, specially removing the bands in the taco method. Or even better getting rid with the taco method for a better one.