C-41 Developing: How does pouring-from-bottle time affect development time?

[MattKing]

Is 500mL really enough for two rolls? The bottom of the tank recommends 500mL per roll, but maybe they mean per tank?

The information on the bottom of the tank doesn't tell you how much of a solution you need to properly perform a particular process. It just tells you how much liquid (of whatever type) you need to cover the film and reel.

In some cases, with quite concentrated chemicals, the amount on the bottom of the tank will have a lot more chemical capacity than the film needs. In other cases, with quite dilute chemicals, the amount on the bottom of the tank will have a lot less chemical capacity than the film needs.

You have to check both the numbers on the bottom, and the capacity recommendations that go with the chemicals. As most colour chemistry is designed to be usable with rotary processing, you probably will be okay, but you need to check.

There are tricks to putting two 120 films on to the same Paterson reel. In essence, you need to take steps to stop one film from moving to overlap with the other. The tape at the end of one roll is used to attach to the other.

 

[RobC]

The jobo tank reels have a little red plastic gizmo which atteches to the reel to stop the films from overlapping.

 

[moodlover]

There are tricks to putting two 120 films on to the same Paterson reel. In essence, you need to take steps to stop one film from moving to overlap with the other. The tape at the end of one roll is used to attach to the other.

Aha, another genius answer! You're brilliant, thank you!!!

 

[moodlover]

Okay actually that trick is much easier said than done. I tried using the tape at the end of the roll to join two rolls together in my darkbag but it was disastrous, not only is it hard to make the rolls line up straight with each other, but the tape gets caught in my plastic Samigon reel and totally stopped the advancement of the rolls!

Desperately, I peeled all the tape off and just loaded the second roll into the reel. Praying they didnt overlap but im not sure how to tell until development is over. Wish me luck

 

[RobC]

folding the tape over the end of the film it is attached to in first place is usually enough to stop films sliding over one another. And if you load films so taped ends meet, i.e first film with taped end going into reel last and second film with taped end going in first, then that makes it even less likely they will overlap.

 

[MattKing]

Okay actually that trick is much easier said than done. I tried using the tape at the end of the roll to join two rolls together in my darkbag but it was disastrous, not only is it hard to make the rolls line up straight with each other, but the tape gets caught in my plastic Samigon reel and totally stopped the advancement of the rolls!

Desperately, I peeled all the tape off and just loaded the second roll into the reel. Praying they didnt overlap but im not sure how to tell until development is over. Wish me luck

You want to do the joining of the two rolls after the second roll is well started into the reel. Push the first roll well past the entrance - at leat half way around the reel - before you add the second roll. Once it has been loaded far enough into the reel to bump up into the first, you then attach them with the tape.

Altenatively, advance the first film all the way to the end. Then load the second film until it just clears the ball bearings. The concern is that the two rolls might wander and overlap. To counter that I would suggest that you not use rotary agitation during the developer stage. In addition, I think, but cannot prove, that a pre-soak helps prevent the film from wandering, because film that goes straight into developer is at its slipperiest.

 

[Sirius Glass]

With Jobo reels load the first 120 film roll and advance it all the way in. Insert the red tab and then load the second roll. The red tab keeps the first roll all the way in and the second roll from passing the red tab itself.

 

[moodlover]

Lost 3 frames due to overlap, never again!

With Jobo reels load the first 120 film roll and advance it all the way in. Insert the red tab and then load the second roll. The red tab keeps the first roll all the way in and the second roll from passing the red tab itself.

Ahh I don't have the jobo reel, is it this one? http://www.freestylephoto.biz/1501-...e-Reel-for-35mm-and-120-for-1500-Series-Tanks

folding the tape over the end of the film it is attached to in first place is usually enough to stop films sliding over one another. And if you load films so taped ends meet, i.e first film with taped end going into reel last and second film with taped end going in first, then that makes it even less likely they will overlap.

This actually makes a lot of sense, folding the tape over the end of the film should make the end thicker, so in effect blocking the next roll that's entering (which the incoming roll should also begin with the tape folded over so they stop each other)! Brilliant, trying this next time!

You want to do the joining of the two rolls after the second roll is well started into the reel. Push the first roll well past the entrance - at leat half way around the reel - before you add the second roll. Once it has been loaded far enough into the reel to bump up into the first, you then attach them with the tape.

Okay this also makes a lot of sense haha, the reel will keep them straight and lined up so first get them into the reel, THEN tape them. What do you think about RobC's method about having taped ends meet?

 

[MattKing]

Lost 3 frames due to overlap, never again!

Did you advance the first roll all the way, as far as it would go into the centre of the reel, before you loaded the second? If not, you may have overlapped them when you loaded them.

If you didn't use any tape between the rolls, you need to leave a gap between the two.

 

[MattKing]

What do you think about RobC's method about having taped ends meet?

It will help - especially if you ensure the first roll is all the way in before your start with the second.

By the way, you advance that first roll into the centre by just pushing the back edge with a finger while you rotate the reel.

FWIW, I do this regularly without tape, but:

1) I'm not doing it with black and white, not colour film, and my solution temperature is room temperature. Those two differences may have an effect on how much tendency there will be for the film to wander; and
2) I use a pre-soak, which may encourage the film to stay put.

 

[Soeren]

I just use my fingers "replacing" the little stainless balls in a normal twisting action to push the first roll all the way in to full stop and then load the second roll. There is some more resistance doing it this way but it works for me.

 

[Sirius Glass]

Lost 3 frames due to overlap, never again!

With Jobo reels load the first 120 film roll and advance it all the way in. Insert the red tab and then load the second roll. The red tab keeps the first roll all the way in and the second roll from passing the red tab itself.

Ahh I don't have the jobo reel, is it this one? http://www.freestylephoto.biz/1501-...e-Reel-for-35mm-and-120-for-1500-Series-Tanks

Yes