Friday, 17 April 2015

RO 9 Special developer.

Recently, I had an unexpected back log of film to process It can be difficult to find the time to do them especially when it is more than a couple of rolls. Anyway a gap opened up so I dived into the darkroom to load two of the rolls ready for development. As I reached for the RO9 my attention was attracted to a couple of bottles of developer standing behind it. RO9 Special and Studional which as it turns out are one and the same along with Rodinal Special. While I was boxing up the first couple of film I had a rush of blood to the head and decided to give the RO9 Special a try. There was method in my madness.

At the time of my decision I had no background knowledge of this developer apart from how it was marketed and the information on the side of the bottle which is sparse to say the least. The blurb stated that RO9s was the finer bread brother of RO9 which was what attracted me to it in the first place. Part of my madness had been influenced by a cassette of HP5+ I had been given to process.

120  FP4+ Negs Developed in RO9s
In stead of jumping in at the deep end with both feet, I thought it prudent to check the very short developing times printed on the side of the bottle by processing a roll of 120 FP4+. Because I have a tendency to slightly under expose my negatives the suggested time of three and a half minutes at a dilution of 1 to 15 was increased to four. I used my standard agitation method of twelve inversions for the first thirty seconds and then four every minute. As there was no indication to the contrary. As soon as the fix was poured out of the tank I checked to see if they had developed properly. From what I could see they looked perfect. I had not intended to do a grain comparison for this film, it was purely to see if the times on the bottle worked in my favour.

The info on the side of the bottle for HP5+ suggested four minutes at 1+15 - I processed the film for five; as it turns out it was a good move. I think the negatives would have been a bit thin otherwise.

I have now researched process times and developer information for RO9s Something I should have done first with a visit Digital truths Dev chart for more times. They tell you to look at Studional.

HP5+ Negs developed in RO9s
Something else I had not been aware of was once the developer had been made up you could use it again. I had a suspicion it could be used again because the concentrate had a syrupy look when I poured it out. In fact you can process up to twelve rolls of mixed formats per litre. The most interesting thing about this developer is that there is no time compensation if you do more than one roll of film on the same day. You only add a compensation factor the longer the working developer in stored. Up to three months.

Developer Data:

RO9 Special/Rodinal Special and Studional.

Characteristics: Fine grain sharp negatives with good contrast. Once diluted can be stored for multiple use. Short process times.

Mixing instructions: Dilute concentrate with water 1+15

Number of Film per Dilution: 10-12 35mm or 120 format per Litre.

Temperature: Is best kept between 18 C and 24C with + or – adjustments as needed to the length of the development time.

Agitation: Tilt the tank for the first minute continuously and then once every minute. You should avoid developing times under three minutes.

Shelf Life: Concentrate should last 2 years in original bottle with no air gap. Once Diluted it should last 3 months without air gap in it's own container.

Time increases for multiple use: To keep speed yield and contrast consistent the diluted developer should be kept in brim full tightly capped bottles if this is achieved the following will apply:

Idle time between
two batches
Development lengthened
few hours (but development none *on same day)
None *
1 – 3 days
4 – 8 days
1 – 2 weeks
over 2 weeks

* with Atomal FF: + 10 %.

The extra times given above do not change if several films are simultaneously processed in one batch.

Suggested development times for use with RO9 special, Rodinal Special and Studional:

Film type
Time *
Agfapan APX 100
4 min
ISO 100/21°
Agfapan APX 400
6 min
ISO 400/27°
Fuji Neopan 400 Prof.
3 min
ISO 320/26°
Fuji Neopan 1600 Prof.
3 min
ISO 800/30°
Ilford PAN-F Plus
3 min
ISO 50/18°
llford FP 4 Plus
3.5 min
ISO 100/21°
Ilford HP 5 Plus
4 min
ISO 400/27°
Ilford Delta 100
3.5 min
ISO 160/23°
Ilford Delta 400
4.5 min
ISO 400/27°
Ilford Delta 3200
6 min
ISO 1250/32°
Ilford SFX 200
4 min
ISO 125/22°
Kodak Plus-X
5 min
ISO 125/22°
Kodak Tri-X
3.5 min
ISO 400/27°
Kodak T-MAX 100
5 min
ISO 80/20°
Kodak T-MAX 400
5 min
ISO 400/27°
Kodak T-MAX p3200
6 min
ISO 1250/32°
Kodak Recording 2475
6 min
ISO 640/29°

  • Small tank or tray processing at 20 °C.
  • Information above supplied by Agfa.

Almost forgot the reason for the rush of blood to the head if you had not already guessed it was to do with the 35 mm HP5+ I find that this films emulsion tends to produce rather grainy negatives with standard RO9. As I intend to enlarge these negatives to 9 x12 the finer developer should make the prints less grainy. I am pleased to say the strategy worked, the negatives have a much finer grain than the standard RO9. The proof of the pudding will be in the printing of the FP4+ and HP5+ negatives. I will share more prints in another post.

9 x 12  photograph from 35mm HP5+ negatives developed in RO9 special