• Welcome to Photrio!
    Registration is fast and free. Join today to unlock search, see fewer ads, and access all forum features.
    Click here to sign up

Inversion agitation instead of a Jobo rotary development

pkr1979

Member
Joined
Jun 25, 2019
Messages
579
Location
Oslo
Format
Multi Format
Hi all,

If you are developing a film at say 10 minutes in a Jobo machine (rotary, no pre soaking) and you would try developing the same film using inversions instead - how would you adjust time?

Cheers
Peter
 
Typically, Jobo recommends reducing development times by 15% from stated tank (hand tank inversion) methods, so it only makes sense to reverse that equation.

Try adding 15% to the successful time you have established on a Jobo.

That would be my recommendation...
 
Thanks guys. Also, is there any chance the Paterson stick could be used to do continuous rotary processing?
 
pkr1979 said:
Thanks guys. Also, is there any chance the Paterson stick could be used to do continuous rotary processing?
Click to expand...

I wouldn't do that; you'd really be courting disaster with directional effects.
 
If you attach the lid and form a vacuum you can place the tank on its side and do 'manual' rotary processing on a roller base or in a basin of water (but it won't float level).

I only use the stick for some initial agitation / air dislodgement before putting on the lid for inversions. An adjustable roller base built from skateboard trucks or something might be a neat project.
 
pkr1979 said:
Hi all,

If you are developing a film at say 10 minutes in a Jobo machine (rotary, no pre soaking) and you would try developing the same film using inversions instead - how would you adjust time?

Cheers
Peter
Click to expand...

In my experience, there is no time adjustment required; I use the same time for both
 
pentaxuser said:
Why? Doesn't the Paterson twirl stick emulate a Jobo processor if you twirl in both directions?

pentaxuser
Click to expand...

In the Jobo, the reel turns with the drum, which is different than the reel spinning in the drum. I would think you would get more "swirling" eddies of chemicals when the reel spins the chemicals rather than allowing the chemicals to flow around the stationary reel.

However, if you are willing to try a reel you can see if it makes a difference.
 
pentaxuser said:
Why? Doesn't the Paterson twirl stick emulate a Jobo processor if you twirl in both directions?

pentaxuser
Click to expand...

With a partially filled tank on it's side on a JOBO or other rotary agitator, the developer is tumbling as the tank and reel rotate.
With a Paterson tank standing stationary on its end and a stick being twirled, the developer is closer to stationary, and the film is rotating through it.
The fluid flow dynamics are totally different.
There is a reason that the instructions for the Paterson tanks recommend that the twirl stick be used only for the first 30 seconds or so of the development process.
 
RalphLambrecht said:
In my experience, there is no time adjustment required; I use the same time for both
Click to expand...

Im not noticing any major difference either, probably better to have a bit more developing than too little.

BTW the Jobo rotary is better than any manual method I have tried for rolled film. If you have one use it.
 
I think it depends on film + developer combination. I once used the intermittent agitation time when developing HP5+ in Ilfotec HC using rotary agitation by accident. Definitely exceeded my normal contrast level, it was noticeable with a naked eye. Lowering time by 15% per Ilford instructions is the right move with that developer.
 
The effect of developer oxidation when rotary agitation is used most likely varies considerably with developer types and volumes used, so I wouldn't expect that one single correction would apply to every circumstance.
It may also be the case that the differences between some inversion agitation schemes - e.g. the Kodak 5 seconds/30 seconds vs. Ilford 10 seconds/minute may also mean that the choice of your inversion agitation scheme may mean that your times end up being closer to the times for rotary agitation.
I do a very Canadian thing - I compromise and use continuous reversing rotary agitation for the first 30 seconds, and then use inversion agitation of 5 seconds/30 seconds thereafter.
 
I used a Paterson tank on an old Sima roller base but was convinced to reduce agitation for better results.

Now I am not so sure there are any benefits!

The next roll of film gets the roller once again.

As I am going to try some high dilutions ( 1:3 ) it should be helpful.
 

the patterson tank comes with instructions? Mine did not..

And swirling the stick works fine... just dont do it in one direction. twirl clockwise twice, then twice the other way,, it works fine.
 

Thanks Matt. Can I take it that someone has been able to demonstrate that the Paterson twirl stick does have an adverse effect on the film compared either inversion or to what is a totally different fluid flow dynamics of a rotary?

I tried to "Google" Paterson twirling stick and the first item that came up was from Photo.net in 2005 when I was still young and foolish. It was this:

https://www.photo.net/forums/topic/200244-patterson-tank-twirling-stick-thingie/

It did seem to sum-up rather well a range of diametrically opposed views expressed by twirlers and inverters. There was one, ronald moravec1 who mentioned the Paterson instructions saying that they said that twirling was for initial agitation only and continued use caused the edges to develop more than the centre but he gave no examples of this and he went on to that reels should be kept away from wetting agents or they will get sticky but then again that remains another item of controversy

Oh and while there was no mention of rotary processing one person did say the stick serves to do rotational processing if you like the effect coming from that kind of processing

I don't suppose you have a link to the Paterson instructions on the use of the twirlie thing do you?

Thanks

pentaxuser
 
Oh and I have now found a 2008 APUG thread where the same divisions emerge between twirlers and agitators In that one the originator who has a Paterson tank that he says he has use a twirl stick as the reel can only be moved that way claiming there is no watertight lid His problem was as follows: " I twirled the stick a few times and moved the tank around on the table instead of inverting as I normally do. The trouble is that I got thin negatives with uneven development. The edges seem to have developed more than the center strip of the film, but there are multiple bands of development visible on many frames.lows: "

He gets told to throw than tank away, plug the holes etc then 2 members tell him that he simply isn't twirling vigorously enough

He gives an update as follows 3 days later:"I've now shot and developed two more rolls in this tank. Thanks to fschifano's and Martin Aislabie's suggestions, I've gotten fine results from both. I simply agitated more vigorously, including roughly 6-8 back-and-forth motions of about 1/3 turn for each 5-second agitation period per 30 seconds (plus the initial 30-second agitation period). "

In this thread we now have redbandit confirming success with twirling. So maybe we need to take out of all that what we will

pentaxuser
 
Thanks all. Considering the Ars-Imago Lab-Box is doing the twirling technique I would expect it to be the same if used in a Paterson. As far as I can tell from quickly reading a few reviews of that it works. Ive never tried it myself though.
 
pkr1979 said:
Thanks all. Considering the Ars-Imago Lab-Box is doing the twirling technique I would expect it to be the same if used in a Paterson. As far as I can tell from quickly reading a few reviews of that it works. Ive never tried it myself though.
Click to expand...

I own one of these. Their fine, so long as you assemble the reels correctly and realize that your "agitation" is one-way only--meaning you cannot rotate the reel counterclockwise or the film will come off of the reel.

I rarely use this thing. But, when I last used it (to process some FOMA films (very thin substrate)), I was able to obtain decent results.

My early attempts at using this box were hit-or-miss because the reels, which come disassembled, were not correctly aligned. You'd think that this was simple, but unless you have excellent eyes, it's difficult to see the alignment marks on the reel and spindle.
 

@TomR55 , is it your experience that the one-way-only-rotation-agitation causes inferior results?
 
No, as long as you vary the speed. I couldn't say, but it seems that reducing my agitation intervals from 4 inversions per minute to 3 inversions (where an "inversion" is a decent clockwise twist) every 30 seconds improved the apparent tonality for Kodak films (which isn't surprising since Kodak recommends 30 second agitation intervals).

The other annoying thing, at least for me, was timing: it takes longer to fill and drain this thing compared to traditional tanks.
 
Twizzel stick , hand rotation with a twist, constant agitation ; I have never had an issue with Paterson tanks or reels.
That said , i once filled with too little solution with 6 x 6.
 
pentaxuser said:
Oh and I have now found a 2008 APUG thread where the same divisions emerge between twirlers and agitators
Click to expand...

Here are a few more:

Do you twiddle?

Way back in the early 70's I was experimenting with various development techniques and equipment. I was looking for the least amount of grain and the best sharpness I could get from Panatomic X and TriX both rated at box speeds. Up until that point I had always developed my film in Honeywell...
www.photrio.com

Twist agitation - has anyone ever done tests?

I know this subject has been discussed about a million times before, but I'd like to get to the root of it. Has anyone ever run actual tests to verify that twiddle stick agitation causes uneven development or is inferior to the inversion method? I've read a fairly large number of threads...
www.photrio.com
 
Like a bad penny, it keeps coming back...
 
pkr1979 said:
Thanks all. Considering the Ars-Imago Lab-Box is doing the twirling technique I would expect it to be the same if used in a Paterson. As far as I can tell from quickly reading a few reviews of that it works. Ive never tried it myself though.
Click to expand...

I did use the original Lab-Box, the Rodinax 35U tank, and it offered good results. I even had it motorised which is smoother than the specified stop-and-go half-turns. No development drag.

Nowadays I have a DIY horizontal tank rotator jig, but just for the fixing stage. Allows for 50% less fixer usage. Added a motor since then.

DSCF7504 by Olivier, on Flickr
 
You must log in or register to reply here.
Menu
Log in
Register