In a recent question regarding Diafine, I noted one of the responses referring to Ilfosol S as Ilford's version of Xtol. I've tried Xtol several times at higher dilutions with good results (HP5+, and FP4+), but am curious about Ilfosol S; that is to say, is this developer chemically similar to Xtol? The Film Development Cookbook makes no reference (that I've found) to any similarities between the two, but perhaps that is because Ilfosol S is a more recent product than the print date of my book. Any input would be appreciated!

-- Dan Lohmann (dlohmann@irem.org), March 20, 2002

Answers

I remember reading something in the Film Developing Cookbook about the two develoeprs not being the same. There still seems to be some amount of disagreement about ascorbic acid as a developing agent and its exact nature of functioning. The designer of XTOL (and Anchell and Troop seem to agree) says ascorbic acid is the primary developer in XTOL. However, in Ilfosol-S, Anchell and Troop suggest that the ascorbic acid is being used to enhance other developing agents - I think this may have been under the ascorbic acid and the environment section. Cheers, DJ.

-- N Dhananjay (dhananjay-nayakankuppam@uiowa.edu), March 20, 2002.

FWIW, I've been using Ilfosol-S for a number of years and like the qualities with the Ilford films I use it with. I only found out recently that it is ascorbic acid based but I don't know any more than that.

I would say I've run well over 150 rolls of 120 & 35 mm film and had zero failures of the kind that some Xtol users have reported. Because I tend to shoot film mostly in the summer, some of the Ilfosol I used had been opened for more than 6 months but it seems to keep well nonetheless.

I'm pretty sure that Xtol came out after Ilfosol because I was using Ilfosol before and I wanted to try Xtol and see what the hubbub was all about. My experience with Xtol was good but limited to 1 roll of Neopan 1600. I still use Ilfosol because it's cheaper and suits my mode of useage.

Cheers,

Duane

-- Duane K (dkucheran@creo.com), March 20, 2002.

Ilfosol has been out for many years...I think since the early '80s. It was originally called Ilford Universal Film Developer. It's a good, inexpensive, reliable developer. I used it for several years with TMX and Delta 100 rollfilm. I think when people call it "Ilford's Xtol" they're referring to similarities in grain and sharpness rather than similarities in chemical composition of the developers.

-- Jon Porter (kodiakalaska@hotmail.com), March 20, 2002.

The two developers aren't the same; Ilfosol-S is PQ/Ascorbate while Xtol contains (I believe) no hydroquinone. It's been my experience that Xtol gives slightly more graininess, acutance and "real" speed but those differences aren't tremendous and may be completely the opposite with different films.

-- John Hicks (jhicks31@bellsouth.net), March 21, 2002.

No they're not the same. Ilfosol-s works 100% reliably!

-- Pete Andrews (p.l.andrews@bham.ac.uk), March 21, 2002.

In the following thread, it was suggested that Ilfosol S is basically a liquid form of ID11, but giving slightly inferior results.

http://www.greenspun.com/bboard/q-and-a-fetch-msg.tcl?msg_id=001Lfr

If that is the case, how does that square with the idea that Ilfosol S is similar in its results to Xtol, which I have never heard described as inferior to ID11 (except perhaps in its reliability!).

Any thoughts comparing ID11, Xtol and Ilfosol S?

-- Ed Hurst (BullMoo@hotmail.com), March 22, 2002.

I am not a chemist so I go by only my personal experiences.

I was using Ilfosol for about a year because it was easily available and is in liquid form, but was getting very grainy, mushy results with Tri-X 400. It was suggested that I use Ilford DD-X or Kodak Xtol and both immediately improved the results beyond my expectations. I use Xtol now since most stores near me just don't stock DD-X. The grain using Xtol is so fine I have great difficulty focusing my Tri-X 400 negatives with a grain magnifier.

-- Todd Frederick (fredrick@hotcity.com), March 23, 2002.

> Any thoughts comparing ID11, Xtol and Ilfosol S?

My standard developer is D-76H 1:1 or 1:3; that's D-76 minus hydroquinone plus slightly more metol, and is functionally equivalent to D-76 or ID-11 as specified by the formulae and may not be the same as the packaged developers.

Xtol is a phenidone-ascorbate low-sulfite developer. With Delta 100 and HP5+ I found Xtol at dilutions from 1:1 to 1:3 to give about 1/3 stop more speed for films developed to the same CI and somewhat more graininess along with a commensurate increase in acutance. Note that whether Xtol gives more or less graininess appears to greatly depend on the film in use.

Ilfosol-S is a PQ-ascorbate developer; the interesting difference is that Ilford adds hydroquinone while Kodak doesn't. At any rate, at the 1:14 dilution with those two films I found it to give comparable speed to D-76H, perhaps slightly more graininess about the same or perhaps more acutance, as is normally expected from a phenidone developer. Specifically considering HP5+ and new Delta 400, Ilfosol-S 1:14 modifies the curve shape a little, inducing more of a shoulder.

This has the potential of making a particularly yucky combination; Delta 400 developed in Ilfosol-S printed on MGIV RC. Every component in the chain reduces highlight contrast.

At any rate, I suggest that any huge, radical differences in results from these three developers are most likely the result of film being developed to quite different CIs.

-- John Hicks (jhicks31@bellsouth.net), March 24, 2002.

Adding a bit to John Hicks comment.

Describing XTOL as low-sulfite formula can be a bit misleading - it has a lot more sulfite than Ilfosol-S 1+14.

The working pH of XTOL is below that of D-76H, while that of Ilforsol-S is much higher. Either way, XTOL and Ilfosol-S are VERY different developers.

-- Ryuji Suzuki (rsuzuki@rs.cncdsl.com), March 24, 2002.

Ilfosol-s doesn't work well with fast films, I'd only recommend it for 100 ISO and slower emulsions.
As John says, it introduces a noticeable shoulder on most films, and for this reason it's particularly useful with T-max and Delta 100. The little bit of extra grain it gives on these films is a reasonable trade-off, IMHO, for more printable highlights and a slight improvement in sharpness over D-76. It works reasonably well with FP4plus, too.

-- Pete Andrews (p.l.andrews@bham.ac.uk), March 25, 2002.