invert or twirl?

D

darkhorse120

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has anyone done any extensive testing on which agitation method is best? I have been processing for years but never found any data proving which is more even/efficient.... I am using 120 film (Tri-x)

I may be opening a can of debate I know.....:)
 
I invert with my own films and metal cans, I teach twirl at the college with the same films in plastic cans. I remain firmly impaled on the fence.
 
I started off with the Paterson tanks which can use either method, inversion of the tank or rotation of the reel. It seemed to me that an inversion of the tank would be more even, because the speed of rotation at the middle and edge of the reel is obviously very different. I have always given about a quarter turn about the vertical axis between each set of inversions, in order to avoid possible 'sloshing' being always in the same place. That said, either system works fine for loads of people !

I stuck with inversion because it was easier, for me, consistently to adjust the amount of agitation by means of the speed or count of inversions.

The main thing is to do something you can repeat and which works. Precisely what, doesn't really matter that much.
 
I've used the Patterson plastic tanks and reels for over 30 years now, and I'm a twirler - agitation by rotation. It's the way I was taught and it works well for me.
 
Lately I just let it stand, might not be the best way but sure is consistent.

In the first minute I twirl.

Wim
 
FrankS said:
I've used the Patterson plastic tanks and reels for over 30 years now, and I'm a twirler - agitation by rotation. It's the way I was taught and it works well for me.
Click to expand...

I was Twirler for about 30 years too...


ibcrewin said:
lol.. I've always thought about this. I invert with a twist ;)
Click to expand...

Now I do it this way...but with a small tap on the bottom before setting it down...
 
I just agitate it by twisting my wrist, then give it a good slam.

Since the goal is to put fresh develop in contact with the negative (and avoid air bubbles), I really don't think it matters.
 
The instructions fo rPaterson say to use the twirl only on first agitation right after adding developer. There is a lot of empty space in the top so inversion works well. You can add a twist if you want.

Relying only on twist rotation will replace used developer more on the edges than center which results in light edges on prints.

Stainless needs multiple inversions, five in 5 sec, or two in five sec with a twist. Kodak website says 5/7 inversions in 5 sec.
Take care not to more developer than necessary so there remains empty space for developer to fill when inverting.

An even better way is to use a two reel tank, one reel with film on bottom, empty on top, and only enough developer for one roll.
Agitate by rolling or inversion.

Our member, Bill Pierce, wrote up the rolling method in the 1960`s in perhaps Modern Photography, and it still works.
 
i do a 1/2 "twist" and then 2-3 inversion (every 60 sec - Paterson 5 reel tanks). Tap it on the sink edge before setting it down.
The tapping can cause the tank to crack though - particularly the 5 reel ones as they are heavy. I stick the tape from various 100/400 ft cans on the edge of the sink as "padding" and it does help.
 
I agitate for 10 - 15 secs of every minute, beginning with an inversion and then swirling the liquid in the tank around and then tapping it hard on some nearby object to dislodge bubbles.
 
I invert the tank while I twirl. :)

Seriously, I do 2 inversions each minute with a swirl and a tap on the last inversion. I am guessing that any distinctions beyond the length of agitation and clearing any air bubbles is more superstitious than scientific. Anything that moves fresh developer across the surface and clears bubbles should do the trick.
 
I twirl because the Paterson tanks I use at the darkroom I develop in don't have the little 'circlip' to keep the reel in the bottom of the tank. Only a problem I suppose if you dont' have the tank full and thinking about it I could put an empty reel in the top of the tank.

Ronnie
 
As my tank is twirl-only, I don't have many choices. I wanted to buy larger volume cocktail shaker style tank for stand development but there were none at the time.
 
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