Why is XTOL so good

[alanrockwood]

From a technical/mechanistic perspective, what is it about XTOL that gives it such a favorable overall profile as a developer, such as combination of low grain, sharpness, and high speed? Is it the use of ascorbate, or is it the use of a phenidone derivative, or does it have something to do with pH or sulfite concentration? What about other factors? Or is it just some magic balance of factors that makes it so good?

 

[jvo]

not as good as rodinal.

(just to get the fur flying!)

 

[removed account4]

not as good as rodinal.

(just to get the fur flying!)

Its probably better with Rodinal IN IT like Les McLean suggests,
or spiked with a little Dektol/Ansco130

alanrockwood, I'm glad it works for you, I was never able to get it to work for me !

 

[Ko.Fe.]

It just takes time to get to HC-110. Take your time, OP.
D-76, XTOL and then it all in hcB.

I asked about it one person who used to print bw darkroom prints for clients and developed film everyday, for clients.
We were at the same page, HC-110.

 

[MattKing]

Do relatively small environmental footprint and ability to act as its own replenisher count?
How about offering an excellent balance of speed, low grain and sharpness?
How about suitability for both large volume and low volume applications?

 

[voceumana]

At rated film speeds, it seems to give 1/3 to 2/3 stop more speed, so you don't have to overdevelop (push) to get a little extra speed; this helps sharpness and tonality. It's a balanced developer (in terms of gradation vs definition) like nearly all of Kodak's developers.

 

[alanrockwood]

I appreciate the comments so far, but what I am trying to learn is why does it have the favorable combination of speed, grain, and sharpness. Scientifically, what gives it those qualities?

 

[mshchem]

Do relatively small environmental footprint and ability to act as its own replenisher count?
How about offering an excellent balance of speed, low grain and sharpness?
How about suitability for both large volume and low volume applications?

+1 Kodak has listed XTOL as having slightly superior properties to other Kodak formulas. I've used tonnes of XTOL . One shot 1:1 in small tanks, replenished in large tanks, straight and 1:1 on Jobo machines.
And I love mixing powders.
Legend from my photo dealer is XTOL is so good, Kodak improved some of their sheet film coating to keep up with the XTOL magic.....? Myth, you decide .
Most developers that are widely used must give good results, or why would they be widely used?
You can take my Kodachrome but stay away from my XTOL

 

[RalphLambrecht]

From a technical/mechanistic perspective, what is it about XTOL that gives it such a favorable overall profile as a developer, such as combination of low grain, sharpness, and high speed? Is it the use of ascorbate, or is it the use of a phenidone derivative, or does it have something to do with pH or sulfite concentration? What about other factors? Or is it just some magic balance of factors that makes it so good?

maybe it has something to do with the 100+ years of experience of the people who came up with it?

 

[1kgcoffee]

I don't particularly like xtol. Other developers may not be as sharp, but have better tonality and nicer grain. Rodinal is super cheap and never dissapoints. Pyrocat has good characteristics in highlights. Similar to xtol with better tonal quality is D76.

 

[Vaughn]

In other words, Alan, we don't know.

But from the comments, it appears that XTOL is not universily accepted as the magic bullet of developers.

 

[removedacct1]

I don't particularly like xtol. Other developers may not be as sharp, but have better tonality and nicer grain. Rodinal is super cheap and never dissapoints. Pyrocat has good characteristics in highlights. Similar to xtol with better tonal quality is D76.

I have found the results discussed in this video to be very similar to my own experience as well, with a variety of films.

 

[MattKing]

If you can find it, the article referenced in this post may help answer your question:
[URL="https://www.photrio.com/forum/threads/non-solvent-developer-with-high-film-speed.125822/#post-1664231"]Non-solvent developer with high film speed[/URL]

 

[Alan Johnson]

http://web.archive.org/web/20050306225024/http://silvergrain.org/Photo-Tech/ascorbate-dev.html
Ryuji Suzuki did most research on this when he was attempting to improve it.

 

[Lachlan Young]

I don't particularly like xtol. Other developers may not be as sharp, but have better tonality and nicer grain. Rodinal is super cheap and never dissapoints. Pyrocat has good characteristics in highlights. Similar to xtol with better tonal quality is D76.

I've found myself quite actively disliking Rodinal - precisely because it has coarser grain & worse sharpness at the same time. 1+3 dilutions of Perceptol, ID-11 etc have much more to offer - & DK-50 type developers are worth investigating too. Most of the time however, I find ID-11/ D-76 at 1+1 offers me the best compromise of speed, grain, sharpness, tonality that I want. Xtol is aimed at greater stability, consistency, environmental/ operator safety in larger scale use.

 

[removed account4]

I have found the results discussed in this video to be very similar to my own experience as well, with a variety of films.

paulbarden: thanks for the link !
I have never used Rodinal and it is nice to see a direct comparison. I had always known of Rodinal being the king of grain for the most part
and by comparison ot Xtol wow, Xtol is the king of smooth tonality and sharpness; i can see why people who can get it to work, well, its their magic juice!
It was also good to see that funky film tank he was going to show. I have an FR and use it very infrequently mainly because it is soooo hard to load...
J

 

[mshchem]

I have found the results discussed in this video to be very similar to my own experience as well, with a variety of films.

Good video. Interesting that the difference really shows up with high speeds and higher magnification.

 

[1kgcoffee]

This video really isn't a fair comparison. Tmax 3200 will have large grain as it is a high speed film, and you are essentially pushing a 1250 speed film to get there. Rodinal is more suited to lower speed films and medium format where you would not notice significant grain at normal enlargement. I'd like to see him compare tonality of the two different developers with a lower speed film such tmax in 6x6.

 

[jim appleyard]

I have found the results discussed in this video to be very similar to my own experience as well, with a variety of films.

I really wonder how fair a test this is. We all know that 3200 is a grainy film and that Rodinal will bring out all that grain. Would the author of the video feel the same if he compared Rodinal & XTol with APX25 or Pan-F? I have trouble finding the grain with my grain enlarger when printing APX 25 negs souped in Rodinal.

 

[1kgcoffee]

Not only that jim, but it seems like the rodinal shot was overdeveloped in comparison to xtol?

 

[removed account4]

I really wonder how fair a test this is. We all know that 3200 is a grainy film and that Rodinal will bring out all that grain. Would the author of the video feel the same if he compared Rodinal & XTol with APX25 or Pan-F? I have trouble finding the grain with my grain enlarger when printing APX 25 negs souped in Rodinal.

IDK Jim
I think that is the point. If Xtol is able to supress the grain in a grainy film like 3200 just think of what smoking a pack a day every day can do to your teeth !?
Rodinal is known for making the most tame films grainy, isn't it ?

Not only that jim, but it seems like the rodinal shot was overdeveloped in comparison to xtol?

IDK 1kgcoffee
Its super hard to over develop anything in Xtol, basically it makes EVERYTHING look flat. I've exposed something like that 3 stops over, and developed it for 4x the time
and it still came out flat ...

 

[Paul Verizzo]

Kodak has supplied this easy to understand graphic of the traits for their major developers. It should end most of the subjectivity here.

https://1drv.ms/u/s!AmOl9vH70YvYlZhXkgBK3js45GMNEg

I'm only an amateur photochemist for the last 35? years. I hate to admit how many hours I must have spent on this hobby. Some would say, wasted. Regardless, and regardless of the fact that I continually learn, here is my two cents:

The performance traits - including the history of sudden death - is all about the ascorbate. Just as the whole industry moved from glycin, amidol, and the pyro's as mainstains many years ago to metol/phenidone/hydroquinone developers, ascorbates are the new frontier. Not really so new, but The Next Big Thing.

Besides appearing to have the superadditivity of hydroquinone, it has the unique trait in that the developer byproducts inhibit further development. At the micro level, that means edge effects, sharpness.

I can't speak to any effects on grain.

I've made an ascorbate based divided developer that is stunning on TMY. I'm picking that line up again now and hope to have the same results with other films. And fine tune the chemistry.

There are smarter people than me out there, if any have other ideas, have at it.

 

[jim appleyard]

Not only that jim, but it seems like the rodinal shot was overdeveloped in comparison to xtol?

Wow, I really can't say. It could be. However, I once shot a few frames of 3200 in 35mm and souped in Rodinal just for fun. I have to admit that it was ugly, and I'm a Rodinal user, but not for everything. Rodinal just isn't made for films like 3200. It's good for what it does, slow & medium speed films, although MF Tri-X looks good even in a 16x20. Yes, a bit grainy, but the tones are nice. One of the things I love about Rodinal is that I can dilute almost any way I want. I really love 1+100. Yes, dev times can get into the 20 min. range, but snow scenes and other highlights come out rather well.

 

[StepheKoontz]

I keep ending up with D76 stock solution for fast film, 1:1 for slow stuff. It always delivers.

 

[removed account4]

The performance traits - including the history of sudden death - is all about the ascorbate.

I don't know about that, a lot of it had to do with how when Kodak came out with their dilution guidelines they would suggest people dilute it 1:10 and in the end
there wasn't enough developer in the dilution to develop the film. If you look at current ( or post 2002 ? ) guidlines they don't even mention 1:10, 1:8.1:6 dilutions. I have no clue the reason why they stopped selling the 1L packages .. Maybe PE will chime in and opine about the "ascorbate" being the problem.