Inversions or Twist Agitations

[Snapshot]

Hi All,

I have been using twist agitation to perform the necessary agitation for developing film. However, I am wondering if there is an advantage to using the inversion technique as a means of agitating? Also, how does twist agitation compare to inverting a tanks? Is a back and forth twist equal to a full inversion?

You input would be appreciated.

 

[MurrayMinchin]

It's been decades since I did roll film, but I used to invert and twist the tank at the same time (invert and twist half a turn, go back with half a turn). Do your negatives come out evenly? I'd be worried that just twisting the tank wouldn't be random enough, and patterns of uneven development would occur.

Murray

 

[jim appleyard]

I've always subcribed to the THEORY that inversion, being 3-dimensional, was a better way to agitate. I use this method with SS tanks/reels.

However, I also own some ancient Ansco plastic tanks/reels (which use back & forth agitation) and use these for developer testing and short rolls/snips.

I cannot see any difference between the two.

 

[Snapshot]

I've been seeing adequate and even development when I twist agitate. The Patterson tanks I've been using have the twist agitator rods to perform the agitating. I was just wondering if this is sufficient or can I get better results with inversions.

 

[radiantdarkroom]

I found twist agitation great for large numbers of rolls 5+. I prefer to the inversion method with metal reels and tanks. I find the metal reels, the fancy expensive ones, are way faster to load and require less chemicals. The twist method seems to develop just as well as the inversion twist together ie no obvious development differences from one end of the roll to the other.

Well of course everyone has a preference to developing film this is just my approach. I run a professional B&W darkroom I'm excited I just made a website: http://theradiantdarkroom.blogspot.com/

 

[Pinholemaster]

I always did both to cover all bases. A good Martini, with a twist, before inversion to my mouth is great too. Grin.

 

[Roger Hicks]

Hi All,

I have been using twist agitation to perform the necessary agitation for developing film. However, I am wondering if there is an advantage to using the inversion technique as a means of agitating? Also, how does twist agitation compare to inverting a tanks? Is a back and forth twist equal to a full inversion?

You input would be appreciated.

It's not important, as long as it's consistent. There are no real equivalents between inversion and agitation (or even, strictly, between inversions with different amounts of dev in the tank). If you are getting even development and nice, printable negs, you're doing it right.

Cheers,

R.

 

[fschifano]

I have plastic tanks with twirling sticks and SS tanks that leave you with no options other than inversion agitation. I get negatives that look the same from both systems.

 

[Sparky]

I've always tried to vary ACCELERATION as much as possible. That means direction changes in the middle of the motion. I figure that the solution inside is only really going to be affected by acceleration - constant movement won't do too much, when you really think about it. One of the very BEST ways to stir up the mix and get exhausted dev off the film is when you SLAM the tank down. I try to be moderately forceful with this - and do it a few times. I've never had an air bell in my life, and I really can't complain about evenness... I'm not saying my method is perfect, mind you... I don't think that at all... that's just a strategy I have....

 

[reub2000]

I figure that the solution inside is only really going to be affected by acceleration - constant movement won't do too much, when you really think about it.

Don't think too hard about. But you are right. Objects inside of a container aren't affected at all by constant motion of said container. That said, inverting a tank subjects it to plenty of acceleration. So does slamming it down on a surface. Which I do after every inversion cycle.

 

[Jerry Thirsty]

I've had a couple of twist type tanks that I had problems with uneven development. I would get more development along the edges near the sprocket holes and less near the middle. So I went back to inversion and have never had a problem since. Maybe I just wasn't doing it thoroughly enough, but I didn't see any reason to possibly waste more rolls of film troubleshooting the procedure when I knew one definite way to fix it.