What differentiates Precysol (EF), Exactol, and DixActol?

[ame01999]

I see their mixing and working procedures differ slightly, but I'm specifically interested in their aesthetic effects. By their descriptions, they all seem to be high acutance developers that provide flexible, compensating development when diluted, and that produce remarkably unobtrusive grain for non-solvent developers. The only comparison I could find within the tech documents was:

"The tanning in Exactol Lux is not as extreme as that with DiXactol Ultra, but is still excellent."

What are your experiences with the developers? Thanks.

 

[Milpool]

Watch out for the marketing. Take those miracle descriptions with a microscopic grain of salt.

 

[ame01999]

Watch out for the marketing. Take those miracle descriptions with a microscopic grain of salt.

I take your point. I just read the FA-1027 film developer "Tech Doc" at Photo Formulary, with its probably apocryphal origin story included, and it read more like an advertisement than a tech doc. But Thornton's book Edge of Darkness documents man's life dedicated to the perfection of the high-resolution photograph, so if the developers were good enough to impress Barry and "convert" him, I suspect there's something worthy of praise. I've only tried Precysol, but found it to be very forgiving with roll film comprising mixed subjects and lighting, producing east-to-print images with fine shadow and highlight detail.

 

[pentaxuser]

I understand there is good reason to believe that Prescysol iEF is as near as dammit PyroCat HD The EF apparently stands for Extra Fine and was, allegedly extra fine for 35mm films

Nothing wrong with Prescysol of course, it's just that there may be "some marketing" afoot in the description of its properties in the sense of the word "marketing" used by Milpool

pentaxuser

 

[Milpool]

I take your point. I just read the FA-1027 film developer "Tech Doc" at Photo Formulary, with its probably apocryphal origin story included, and it read more like an advertisement than a tech doc. But Thornton's book Edge of Darkness documents man's life dedicated to the perfection of the high-resolution photograph, so if the developers were good enough to impress Barry and "convert" him, I suspect there's something worthy of praise. I've only tried Precysol, but found it to be very forgiving with roll film comprising mixed subjects and lighting, producing east-to-print images with fine shadow and highlight detail.

We can look (roughly) at the formulation of each but ultimately you’ll probably be on your own when it comes to any sort of practical comparison.

They are all formulated to be staining developers.

Exactol Lux appears to be essentially a low-sulfite, Phenidone-catechol developer with a high pH alkali (carbonate/hydroxide), probably very similar if not virtually identical in working characteristics to Pyrocat-HD.

Prescysol EF seems to be a metol-catechol developer with some glycin as well. Again, low sulfite and carbonate alkali. The characteristic curve may or may not be different than other staining developers.

Dixactol/Dixactol Ultra seem to be more along the lines of the old Windisch catechol-hydroxide developer but intended for two-bath development. They also contain glycin and bromide (to reduce fog). I’m not sure what the difference is between the two Dixactol developers.

None of these are going to be fine grain developers regardless of any supposed “grain masking”. The extent to which they produce finer grain than other acutance formulas is something you’ll have to decide for yourself.

 

[AnselMortensen]

I get good results with Dammitol.

 

[ame01999]

We can look (roughly) at the formulation of each but ultimately you’ll probably be on your own when it comes to any sort of practical comparison.

They are all formulated to be staining developers.

Exactol Lux appears to be essentially a low-sulfite, Phenidone-catechol developer with a high pH alkali (carbonate/hydroxide), probably very similar if not virtually identical in working characteristics to Pyrocat-HD.

Prescysol EF seems to be a metol-catechol developer with some glycin as well. Again, low sulfite and carbonate alkali. The characteristic curve may or may not be different than other staining developers.

Dixactol/Dixactol Ultra seem to be more along the lines of the old Windisch catechol-hydroxide developer but intended for two-bath development. They also contain glycin and bromide (to reduce fog). I’m not sure what the difference is between the two Dixactol developers.

None of these are going to be fine grain developers regardless of any supposed “grain masking”. The extent to which they produce finer grain than other acutance formulas is something you’ll have to decide for yourself.

Thank you, Milpool, that was helpful.

 

[ame01999]

Thank you, Milpool, that was helpful. And I assume FA-1027 is proprietary? I haven't found a formula for it anywhere. I'm surprised it wasn't mentioned at all int he latest Developing Cookbook, formula or not.

 

[Milpool]

These are all proprietary in that the formula is not disclosed. In the cases of Prescysol, Exactol and Dixactol we can get a rough idea of the compositions based on combining the descriptions (eg staining means low sulfite…) with the information disclosed on the safety data sheets.

In the case of FA-1027 we have no SDS that I know of. We know it is a PQ developer, and that it contains both Benzotriazole and KBr, but it’s hard to say much else. The (utterly ridiculous) description/ad copy claims first that it is an acutance developer, so perhaps begin with that assumption if you want to try it. I can guarantee it does nothing special, but there’s never any harm in trying something - it’s part of the hobby.

 

[xkaes]

For what its worth:

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DiXactol Ultra (type) Developer​ Stock Solution A Sodium Sulphite 3 g Glycin 2 g Pyrocatechin 10 g Phenidone 0.2 g Sodium Metabisulphite 5 g Water to 100 ml Stock Solution B Sodium Hydroxide 10 g Distilled water to make 100 ml To make a standard working solution, mix 1 part A with 1 part B with 100 parts water.​

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