Acuspecial FX21 developer as alternative to stand development

[Augustus Caesar]

The numbers don't make any sense. But what gives; just round them to .1. Except the phenidone. That one can best be mixed as e.g. a 1% concentrate in glycol and then dosed with a pipette unless very large batches are being made.

Round to your taste. These are the numbers from the formula. I give them as I received them.

 

[Augustus Caesar]

Me neither and I have major doubts that a reasonably priced set of scales from Amazon is accurate to what is 4 decimal places but no others seem to be questioning this so maybe we are wrong and 2.1496 or 2. 1494 is sufficiently wrong to affect FX21's efficacy.

pentaxuser

I mix up and round off. It's difficult to get them to this accuracy, and unnecessary.

 

[Keith Tapscott.]

Yes!

Thanks.

 

[koraks]

Round to your taste. These are the numbers from the formula. I give them as I received them.

Thanks; I wonder (haven't checked) if the numbers perhaps make sense from a stoichiometry viewpoint. I suspect that may be the reason why they're so odd.

 

[bernard_L]

The correct formula:

For 15x concentrate:

All weights in grammes per litre. For T-Max 400, use 1+9 for 11 minutes. For slower films (FP4+, T-Max 100, Delta 100), dilute more (1+14). For Pan-F, dilute 1+19, try 8 minutes to start. For Delta 400, try the same as for T-Max 400, to start with.

I am not sure how well Delta 3200 or T-Max 3200 will do in this developer, but try 1+5 dilution for 10-12 minutes.

Component	Amount in grammes
Metol	2.1495
Sodium Sulfite	30.0
Hydroquinone	1.0995
Phenidone	0.1245
Sodium Metabisulfite	6.15
Potassium Carbonate (monohydrated)	22.035
Sodium Bicarbonate	3.9
Sodium Citrate	3.9
Potassium Iodide	0.0825
Potassium Bromide	0.33
Sodium Hydroxide	5.0

Hmmm... What is still missing in that formula? I'm sure with some metaborate and 1.054g of Glycin it would perform much better. </sarcasm>

 

[lamerko]

These weight values are probably converted from another unit of measurement. They can be rounded to a reasonable accuracy. Regarding the carbonate - put in the one you have, just calculate the weight relative to the monohydrate. There is no monohydrate available here, only the anhydrous form. I assume that the original formula used something from the nearest general store. Unfortunately, there is no data on the pH of the working solution.

 

[Augustus Caesar]

These weight values are probably converted from another unit of measurement. They can be rounded to a reasonable accuracy. Regarding the carbonate - put in the one you have, just calculate the weight relative to the monohydrate. There is no monohydrate available here, only the anhydrous form. I assume that the original formula used something from the nearest general store. Unfortunately, there is no data on the pH of the working solution.

The commonest form of Sodium Carbonate available (at least in the US) is the mono-hydrate. The anhydrous form slowly absorbs water from the atmosphere and eventually becomes mono-hydrate. To convert mono-hydrate to anhydrous, multiply by about 0.855.

 

[Andrew O'Neill]

I have heaps of anhydrous form, but I do have the mono-hydrate on order (from Argentix) but sadly it has been sitting in limbo land, due to Postal strike. With no end in sight to that mess, I'll just go ahead and use the anhydrous form...

 

[Sidd]

The correct formula:

For 15x concentrate:

All weights in grammes per litre. For T-Max 400, use 1+9 for 11 minutes. For slower films (FP4+, T-Max 100, Delta 100), dilute more (1+14). For Pan-F, dilute 1+19, try 8 minutes to start. For Delta 400, try the same as for T-Max 400, to start with.

I am not sure how well Delta 3200 or T-Max 3200 will do in this developer, but try 1+5 dilution for 10-12 minutes.

Component	Amount in grammes
Metol	2.1495
Sodium Sulfite	30.0
Hydroquinone	1.0995
Phenidone	0.1245
Sodium Metabisulfite	6.15
Potassium Carbonate (monohydrated)	22.035
Sodium Bicarbonate	3.9
Sodium Citrate	3.9
Potassium Iodide	0.0825
Potassium Bromide	0.33
Sodium Hydroxide	5.0

But how to measure those .5 mg levels of chemicals!

 

[Keith Tapscott.]

I would like Bill Troop to contribute to this thread as I believe it's from the FDC2.

 

[koraks]

I would like Bill Troop to contribute to this thread as I believe it's from the FDC2.

See #5. If you follow the link, you'll notice Bill Troop has in fact commented on the formula, although AFAIK (didn't read all of the 5 pages) not on the quantities, apart from some discussion of the buffering system and its required exactness.

Acuspecial FX-21 formula (Better than Rodinal!)

FX-21 developer formula for 1+14 dilution. All weights in grammes per litre. I do not yet have any development times. Component Amount in grammes Rounded Amount Metol 2.1495 2.15 Sodium Sulfite 30.0 30.0 Hydroquinone 1.0995 1.1 Phenidone 0.1245 0.125 Sodium Metabisulfite 6.15 6.2 Potassium Carbon...

www.l-camera-forum.com

 

[Andrew O'Neill]

But how to measure those .5 mg levels of chemicals!

Either pick up a scale on Amazon that'll do mg (I picked up a cheap digital one there), or round up the numbers.

 

[snusmumriken]

It’s a bit of a Christmas pudding, isn’t it? I mean, it seems to have a bit of everything in it, including 3 developing agents. Would anyone care to suggest how it might all work?

 

[Sidd]

Either pick up a scale on Amazon that'll do mg (I picked up a cheap digital one there), or round up the numbers.

I have just prepared a 15x concentrate. It's not very difficult with my 10 mg scale. Only potassium iodide was an issue, I just prepared a 1% solution and took required amount of solution.

 

[Sidd]

Any information regarding the longevity of the 15x concentrate?

 

[Andrew O'Neill]

It’s a bit of a Christmas pudding, isn’t it? I mean, it seems to have a bit of everything in it, including 3 developing agents. Would anyone care to suggest how it might all work?

It seems to be a bit over the top as far as ingredients go. I've never mixed up a developer with so much going in...especially after working with D-23 the past few weeks! Currently, I'm working on a video where I'll compare it with semi-stand in Pyrocat-HD.

 

[Keith Tapscott.]

It’s a bit of a Christmas pudding, isn’t it? I mean, it seems to have a bit of everything in it, including 3 developing agents. Would anyone care to suggest how it might all work?

If you think this formula is complicated, have a look at the MSDS for Spurs HRX. If I remember correctly, it's got two or three different types of Phenidone etc

 

[Augustus Caesar]

Any information regarding the longevity of the 15x concentrate?

Not sure. I usually make it up fresh each time I use it, then process a bunch of film.

 

[lamerko]

Any information regarding the longevity of the 15x concentrate?

I expect the working solution to last no more than 2-3 hours. For the concentrate - it depends a lot on how it is stored, but probably no more than three months. If the concentrate is made in two parts - the first glycol, the developing agents, potassium metabisulfite (replacing the sodium one from the original formula) and the limiters, and in the second - everything else. If the formula is changed to potassium, the concentration can become much larger and with a higher durability.
This formula is a little strange to me - I'm not a chemist, but from what I understand, the metabisulfite will react quickly with the hydroxide to form a sulfite with a very slight excess of hydroxide. These components are a little strange to me.

 

[Augustus Caesar]

I expect the working solution to last no more than 2-3 hours. For the concentrate - it depends a lot on how it is stored, but probably no more than three months. If the concentrate is made in two parts - the first glycol, the developing agents, potassium metabisulfite (replacing the sodium one from the original formula) and the limiters, and in the second - everything else. If the formula is changed to potassium, the concentration can become much larger and with a higher durability.
This formula is a little strange to me - I'm not a chemist, but from what I understand, the metabisulfite will react quickly with the hydroxide to form a sulfite with a very slight excess of hydroxide. These components are a little strange to me.

It was sold commercially as Acuspecial by Paterson. Designed by Crawley. I know it works well, as I have used it for several rolls now. Just keep the agitation normal (2 inversions once per minute, with a twist) and it should work for you too.

Paterson 'Acu' Range

Paterson, Chemicals

www.photomemorabilia.co.uk

 

[Sidd]

I expect the working solution to last no more than 2-3 hours. For the concentrate - it depends a lot on how it is stored, but probably no more than three months. If the concentrate is made in two parts - the first glycol, the developing agents, potassium metabisulfite (replacing the sodium one from the original formula) and the limiters, and in the second - everything else. If the formula is changed to potassium, the concentration can become much larger and with a higher durability.
This formula is a little strange to me - I'm not a chemist, but from what I understand, the metabisulfite will react quickly with the hydroxide to form a sulfite with a very slight excess of hydroxide. These components are a little strange to me.

I'll definitely try your suggestion of making Propylene Glycol solution of the developing agents, but, I'll first get myself used to the developer itself.

 

[pentaxuser]

after working with D-23 the past few weeks! Currently, I'm working on a video where I'll compare it with semi-stand in Pyrocat-HD.

That will be an interesting video, Andy. Seeing you mention D23 has reminded me that John Finch did a video comparing FX55 with D23

pentaxuser

 

[Sidd]

Disheartening failure with my first try with FX-21! The negative came out blank! Don't know whether the developer got contaminated somehow? Used 1:14 for Tmax 100, 8 minutes @23°C.

 

[koraks]

Sounds like a mixing error, or mistaking the fixer for the developer resulting in the film being fixed before it could be developed.

 

[lamerko]

How much iodide did you put in the concentrate? And how much hydroxide? If you are unsure about the iodide measurement, it is better to skip it...