To Invert, or Not to Invert? That is the Question...

LeicaVirgin1 · 07-24-2009

Dear Sir, (or anyone else for that matter),

As posted earlier; I have the Twin Plastic Spool type of developing tank made by AP that is made is Spain, or somewhere in the EU. It is similiar to the Patterson version, but this one has a stick so the user can rotate the spool(s) and have them "bob" up and down all with a single turn, (The manufacturer recommends this method over the other technique which is the "Inversion" method).

The reason they explain why the stick-rotate/"bob" technique is better than the "inversion method" is that the former will not have a chance to "possibly" leak; like the "inversion" method/technique.

Is one ,or the other a better way for more consistent neg. development etc., etc.?

Looking forward to your response(s).

Best,

LV1

Chriscrawfordphoto · 07-24-2009

Inversion is the standard method and always has been since the invention of the daylight rollfilm tank 100 yrs ago. The twirling method can produce uneven developing because film near the outside of the spool travels at a higher speed than that in the center, producing greater agitation on one end of the roll than the other. Also it doesn't move the developer around as much as inversion so you may still not get enough agitation to break up the layer of exhausted chemistry that concentrates on the emulsion surface as development progresses.

Roger Hicks · 07-25-2009

It doesn't actually matter a damn. As long as there's enough agitation, and it's random, anything will work. For sensitometry, brush agitation (yes, sweeping the film with a soft brush) is or at least was the standard.

Chris is quite right in theory but the risk in real life with a spiral or apron tank is negligible, given the turbulence and narrow gaps between the film. All that matters is that the developer in contact with the film is replaced often enough (which any reasonably frequent agitation will do) and that the agitation is random so that fresh developer doesn't stream past some parts at a constant higher rate. The back-and-forth 'twiddle' is quite enough to ensure this.

Cheers,

Roger

ruby.monkey · 07-25-2009

I've found that inversion is far less likely to cause hand cramp than is twiddling, but both methods are equally fine for developing.

Tom A · 07-25-2009

I have used both methods, but these days it is strictly inversion "routine". It doesn't really matter as long as you get even development.
The "swirling" works well if you do large tanks (8-10 reel tanks) as they become very heavy to lift and the sheer volume of liquid can stress the tank and crack it (plastic ones).
Small tanks require more agitation as a rule - just establish a routine and stick to it. This way you eliminate one "unknown" factor.
The Paterson tanks remains fairly leakproof if you "burp" the lid when putting it on (lift the edge, press down in the center) - but it is always a good idea to hold the tank with two hands - one of which is holding down the lid! I have had 8 reel paterson tanks pop the lid and dump 2.5 ltr of developer over the sink and me!!!!
I used to use a "basket" developing system with a nitrogen burst - worked fine with color but could create problem with black and white. Advantage we that you could load 24 rolls of 35 in a single run,

LeicaVirgin1 · 07-25-2009

To Everyone Who Contributed to My Post-

Thank you so very much. This is a great site. Where else can you get actual user advise? Thanks Tom, Roger, Chris, & IdeaDog you have been a great help!

Also, Mr. Hicks I have one of yours & Francis' Book-"Quality Photography".... Great Book!

Mr. Tom A., I need to find out how to invest in your standard size softies for my "M's"... I go to your site, but to no avail. Am I missing something?

Cheers,

LV1

Chriscrawfordphoto · 07-25-2009

If Tom doesn't sell softies directly, you can buy them from CameraQuest.com which is our host, Stephen Gandy's store. I have a mini-softie on my Bessa R2. Bought the mini from Mr. Gandy and it arrived 2 days after i ordered it.

Tom A · 07-26-2009

Quote:

Originally Posted by LeicaVirgin1

To Everyone Who Contributed to My Post-

Thank you so very much. This is a great site. Where else can you get actual user advise? Thanks Tom, Roger, Chris, & IdeaDog you have been a great help!

Also, Mr. Hicks I have one of yours & Francis' Book-"Quality Photography".... Great Book!

Mr. Tom A., I need to find out how to invest in your standard size softies for my "M's"... I go to your site, but to no avail. Am I missing something?

Cheers,

LV1

Just email me on our regular email TTabrahams@shaw.ca and Tuulikki will handle it.
Tom

Rayt · 07-26-2009

I continuously invert the first minute to make sure all the bubbles are out and then invert for 5 seconds every 30 seconds. I have been doing this for nearly 20 years and no surprises so far.

I gave away my Paterson tanks after going digital with the M8 and then regretted it and then bought a few AP tanks and reels. Perhaps I am used to the Paterson reels but the AP reels are just crap. I have ruined my first two rolls of 120. The film jams half way into the load. I have since tossed out the AP reels and ordered Paterson tanks and reels and a couple of stainless Hewes for 120 to make thing interesting. The downside of digital is not having to process film

Al Kaplan · 07-26-2009

I never ran into any problems souping B&W with nitrogen burst agitation using those racks in 3.5 gallon tanks.

Fotch · 07-26-2009

I have Nikor stainless steel which includes the lids, never leaked. I remember years ago, some brand ss came with a wide rubber band to put over the joint. The Nikor are the best.

btgc · 07-26-2009

I'm another one using twirl tank. Only two rolls so far, though no problems with unevenness.