Increasing Sharpness through Agitation

Film Photography & Darkroom discussion

Moderator: Keith Tapscott.

Posts: 21
Joined: Thu Sep 15, 2005 1:46 pm

Post by tornredcarpet »

Ooh I have that book. Excellent, excellent book.

Posts: 21
Joined: Thu Sep 15, 2005 1:46 pm

Post by tornredcarpet »

Another point I want to bring up. Reducing agitation has bound to require increasing development time for the same development... what's a good multiplier?
I.e. My agitation is continuously the first 30 secs (stand for rest of the first minute), then 5 secs (3 inversions for small tank) every 30 seconds.
Now it's like what? agitate 5 seconds every minute? How do I adjust development time?
Or large tank... I agitate continuously the first 30 seconds (stand for the rest of the first minute), then 15 seconds (two cycles) every 30 seconds. Agitating once a minute or once every two minutes, what happens?

Posts: 183
Joined: Sat Dec 10, 2005 11:01 am
Location: Fairview, Oregon

Post by foolscape »

I haven't tried them yet, but I've heard that pyro developers make sharp images. There's an updated pyro recipe on this site that eliminates some of the uncertainty of the older ones. If it's true, this would be a more consistant way to insrease sharpness without standing in the dark for an hour.


Lowell Huff
Posts: 129
Joined: Thu Aug 19, 2004 6:09 pm
Location: Los Angeles, CA 90061

Post by Lowell Huff »

Why don't we use the chemicals, films and papers as the manufacturer recommends to use them? If you need better image quality, use a better developer. We have learned several things about the relationship between silver halide and how to make developers and fixers since the 1920s. It just so happens that our F 76 plus Developer and Extend plus Developers are great examples of that increase in technology and chemical knowledge. I will supply samples, contact me.

Posts: 3
Joined: Tue Jan 10, 2006 5:50 pm

to answer your question....

Post by mikeseb »

You have had a variety of responses here, some to questions you haven't asked, and some of those not completely accurate.

Using the Xtol you have on hand, your best bet for increased "sharpness" would be to dilute it to 1:2 or more. As a bonus it will have a greater compensating effect, but grain will be more apparent. This may not be entirely bad, given that grain gives a visual "tooth" that can make the image seem sharper. If you start with a finer-grained film, like FP4, PlusX, TMax, or Delta, you should get nice results with dilute Xtol. I develop these films with it routinely.

Someone here has recycled the old myth about Xtol's premature exhaustion. To my knowledge this was a problem mainly with the old 1-liter batches. I've not encountered it with the 5-liter batches, but then store it in multiple 250 mL bottles and use it only once and discard, regardless of dilution.

I also wouldn't bother too much speculating about kodak's future in the film/developer business. There are plenty of ascorbic-acid developer formulas you can make yourself to replace it, such as Mytol.
michael sebastian

Posts: 878
Joined: Thu Jan 19, 2006 9:49 am

Re: Increasing Sharpness through Agitation

Post by Ornello »

tornredcarpet wrote:I've heard stories about how it was was possible to increase the sharpness of your negatives by agitating less.
Anyone care to share some techniques?

The film/dev i am concerned with is TMY (sheet) in XTOL stock or 1:1, processed in a large tank.
People have complained that it looked too smooth so those people have tried developing in Rodinal 1:100. Since I have my 5 liters on XTOL already on hand, I would prefer just using XTOL.

Thanks a lot!
The agitation pattern or frequency has no effect on sharpness, only on acutance.

No, it is not necessary to agitate less than the recommended amount. Most people agitate too frequently and too violently, especially beginners. The instructions on agitation given by manufacturers are sometimes interpreted too liberally.

Simply use two brief, gentle inversions, once per minute. The tank should remain motionless about 50-55 seconds of each minute. The use of an acutance developer such as Acutol or FX-39 will help. Rodinal is a poor developer by any standard, and does not offer greater sharpness; in fact it offers poorer sharpness. It accentuates grain, and to some people this looks like greater sharpness, but in fact Rodinal has poor sharpness and offers poor emulsion speed. Some myths die very, very hard.

T-Max films look very smooth because of the way they are constructed. I do not use them because I prefer conventional films.

Post Reply