Highest safe temperature for B&W film?

[Вormental_old]

What he needs, it seems to me, is for someone who knows to tell him how long he needs to wait until he pours in his dev,stop and fix at say 70F before he runs any risk of reticulation?

Nope, that's not what he needs and that's not what he asked. He measured the film temperature with an IR thermometer after a 100F pre-wash and observed it dropping to ambient extremely rapidly. The temperature in question is pre-soak temperature only. The development, and he said this a few times above, will be done with his normal process at 21C.

 

[pentaxuser]

OK so you know when the film in the empty tank post the pre-wash stage is at ambient temp - great! So you are good to go now and there's no need for us to be more worried about potential problems that don't in fact exist

Let us all know if there are any emulsion problems after the higher temp pre-wash and if the higher temp pre-wash helps cure or better still eradicates the white dot problem

Yes I did always understand that the rest of the process would be done at normal process temp of 21C I am glad we can use Centrigrade. Most in the U.S. still seem to want to use Fahrenheit, fluid ozs, U.S gallons and not the metric system

Go for it, Bormental.

pentaxuser

 

[cmacd123]

the Foma 400 data sheet gives development temperatures from 20 to 30 C. Proably a good idea to stick with that range.

I am not sure what the Dye issue is. when I poor out my developer with Fomapan it is often a lovely shade of Green. a few minutes in Rapid fixer after development and I don't notice any colour on the negatives. Unless you are using one of the "drift by"methods to control developing temperature I figgure that Presoaking is just a way to dilute the developer.

 

[grat]

For what it's worth, I develop my Arista EDU Ultra 400 (Foma 400 Action) 4x5 film at 68 degrees, and pre-wash for 30 seconds, continuous agitation with swizzle stick (about 10 seconds one direction, then 10 the other). Then I repeat the rinse after the developer and before the stop bath (again-- 68 degrees, 30 seconds, continuous swizzle). I see no emerald green dye in either the developer pour-out, or the second rinse, so it seems that the first rinse is enough to remove all of the dye. I'll probably drop the post-developer rinse (trying to avoid contaminating my stop).

Film seems to come out OK-- I get the occasional missing blob of emulsion, but it's usually very small, and not very many.

 

[removed account4]

last time I processed film at a higher temp than 85-86º the emulsion all slid off the film . it was foma film, 120 and 35mm. --- about 6 rolls of it. i had no trouble processing the IDK 15-20 rolls i developed using normal water. I would be leery of soaking film for 20 minutes in hot water. (i'm not green but have processed film for myself and professionally for others since 1980 and it is one of the very few times i have ever had a problem developing film (1000s of rolls and sheets of it)). just use 68º water. drastic measures like the hot soak to save a few mins extra of soak time seem excessive especially since, well the seconds you stole from the river of time will never present themselves to you again.

 

[koraks]

I'll probably drop the post-developer rinse (trying to avoid contaminating my stop).

Keeping the rinse will in fact be easier on the stop than not rinsing. Not that it matters much. How expensive is stop, a dash of vinegar or a teaspoon of citric acid?

 

[Donald Qualls]

Rinsing before stop has one bad effect: it doesn't stop the development with any precision (or quite possibly with any evenness). Stop bath exists for one purpose: to quickly and evenly change the pH of the gelatin environment so the developer quits working. If that doesn't occur in a predictable and consistent fashion, your development may vary from one tank to the next or even from one edge of the film to the other.

 

[NB23]

If I trust my intelligence, one would need to presoak before shooting. That would be in order not to shoot over the dots/bad emulsion, yeah?

Why soak AFTER having exposed the film? Does it really solve the problem?

Presoak, dry the film, rewind back into the cassete. Ready to shoot.

 

[pentaxuser]

If I have understood Bormental's position, it is that he has narrowed down his options to one, namely pre-washing at or slightly above 30C. This would appear to be his last hope. This is what seems to have worked at slightly lower temperatures but hasn't quite eliminated the problem so that leaves only the option of using pre-wash at 30C

The risk with the emulsion is just one that cannot be avoided

pentaxuser

 

[Donald Qualls]

If I trust my intelligence, one would need to presoak before shooting. That would be in order not to shoot over the dots/bad emulsion, yeah?

Presoak, dry the film, rewind back into the cassete. Ready to shoot.

First, AFAIK this has only been a issue in 120 (and maybe sheet films). Second, the antihalation dye is under the sensitive emulsion layer(s), so won't affect exposure unless by chemical processes -- in which case it'll be too late by the time you receive the film.

 

[pentaxuser]

If I trust my intelligence, one would need to presoak before shooting. That would be in order not to shoot over the dots/bad emulsion, yeah?

Why soak AFTER having exposed the film? Does it really solve the problem?

Presoak, dry the film, rewind back into the cassete. Ready to shoot.

Now that does seem both novel and logical and certainly beats what I think Bormental has narrowed down as his remaining option, namely hot pre-wash after exposure

Worth thinking about, Bormental

pentaxuser

 

[grat]

Keeping the rinse will in fact be easier on the stop than not rinsing. Not that it matters much. How expensive is stop, a dash of vinegar or a teaspoon of citric acid?

Rinsing before stop has one bad effect: it doesn't stop the development with any precision (or quite possibly with any evenness).

And those are the two arguments I've been chasing. The rinse will effectively dilute any remaining developer to "practically nothing", and I haven't seen any signs of uneven development. But I'm also aware that water is not a stop bath (unless you've got some really nasty water!), and all it does is displace the developer.

 

[grat]

First, AFAIK this has only been a issue in 120 (and maybe sheet films). Second, the antihalation dye is under the sensitive emulsion layer(s), so won't affect exposure unless by chemical processes -- in which case it'll be too late by the time you receive the film.

I thought the anti-halation coating was on the backside of the film? One side is coated with the emulsion, one side is coated with the dye... which also means I don't know how the anti-halation is causing your emulsion to be spotty, but if that's what Foma said, I would hope they would know.

 

[Deleted member 88956]

And those are the two arguments I've been chasing. The rinse will effectively dilute any remaining developer to "practically nothing", and I haven't seen any signs of uneven development. But I'm also aware that water is not a stop bath (unless you've got some really nasty water!), and all it does is displace the developer.

I have quite often (not routinely) rinsed after developer and before fixing (never used stop bath). Never have I seen a difference in final outcome. But I suppose it is possible to make things worse with rinse after developer..

 

[Donald Qualls]

I thought the anti-halation coating was on the backside of the film? One side is coated with the emulsion, one side is coated with the dye... which also means I don't know how the anti-halation is causing your emulsion to be spotty, but if that's what Foma said, I would hope they would know.

Some films have the antihalation on the base side, others have it under the emulsion on the emulsion side (dye can be either way, silver AHU is always on the emulsion side). Either way, the spots are due to locally high dye density (undissolved from the original layer coating?) that fails to fully dissolve away during processing -- these form specks that print white, just as anything else (like dust) that blocks light during scanning/printing.

 

[takilmaboxer]

I love Foma 100 and I have never had this problem. If you do then you have a darkroom problem. It's You, not the film.

 

[Deleted member 88956]

Just curious why is this about Foma when film was purchased from Freestyle? Does not make any difference who produced it, Freestyle should be taken outside for man talk.

 

[BradS]

Just curious why is this about Foma when film was purchased from Freestyle? Does not make any difference who produced it, Freestyle should be taken outside for man talk.

Why would the retailer bear any responsibility at all for the manufacturer's poor quality ?
Foma film is known to be lower quality than Kodak, Ilford and Fuji...and the lower price reflects that.
People buy it accepting that it is comparatively low quality in order to save money.

Again...why would this have anything at all to do with the retailer?

 

[MattKing]

I'm trying to figure out why a pre-rinse would treat this problem, while an extended wash would not.

 

[Вormental_old]

I'm trying to figure out why a pre-rinse would treat this problem, while an extended wash would not.

I wonder this too! Mainly, I'm doing this because that's what their support recommended.

 

[Deleted member 88956]

Why would the retailer bear any responsibility at all for the manufacturer's poor quality ?
Foma film is known to be lower quality than Kodak, Ilford and Fuji...and the lower price reflects that.
People buy it accepting that it is comparatively low quality in order to save money.

Again...why would this have anything at all to do with the retailer?

Is Freestyle branded Foma? I was under impression it is not. And Freestyle is not selling it at cost either, is it?

 

[Вormental_old]

Freestyle's Arista EDU Ultra is Foma.

 

[Deleted member 88956]

Is Freestyle branded Foma? I was under impression it is not. And Freestyle is not selling it at cost either, is it?

And to take this a bit further: it is a fact a Chinese factory puts out thousands upon thousands of pieces of whatever a day, same pieces but labeled with all kinds of "brand names". When that "brand" takes delivery, it is that "brand" that covers any problems. Same here. So unless Freestyle has contract agreement with Foma that says |you got a problem with this product, call Foma, here is the number", and it is in every box of film Freestyle sells, than the answer is or ought to be " you got a problem call us"

 

[removed account4]

I'm trying to figure out why a pre-rinse would treat this problem, while an extended wash would not.

its kind of like putting the peanut butter down before the jelly, or the other way around

 

[Donald Qualls]

Freestyle almost certainly gets a big discount from Foma for buying in container lot (or larger) quantities -- which allows them to take a markup and make a profit selling the film a few cents a roll cheaper than Foma's retail (or in other words, Freestyle paid less for the film they relabel than they do for actual Foma-packaged film).