Time for Ilford HP5 @ EI 1600 in LC29 1:29?

[altair]

Hi all. Does anyone know the time for the above? My previous batch of LC29 at 1:19 dilution has been exhausted (turned to deep purple in color!), and I'm thinking of mixing up a new batch of working solution but at 1:29. Would appreciate if anyone can provide me with the time, preferably at 20C (I work at 28C but I can adjust the times from 20C if need be).

Thanks in advance!

P.S: By the way, I wonder why Ilford LC29 at 1:29 has not much info/times on it? Ilford's literature strangely lacks times for LC29 1:29, but has numerous times for 1:19 and other dilutions.

 

[maarten m]

i haven't tried this, but my guess would be a 20min LC29 1:29 in 20°C for HP5+ at 1600 iso.

seeing that 1:9 gives 7:30 and 1:19 (half that strength) almost doubles it to 14:00.
at 400 iso, the rate between 1:19 and 1:29 is close to (a little less then) 1,5 times (6:30 to 9:00), which is also the solution-rate (2/3).

please share your findings?

maarten.

 

[altair]

Maarten, thanks for your input. I've decided to go with 1:19 instead of 1:29. I've developed several rolls of HP5 at EI1600 in LC29 1:19. My findings: 12 mins at 28C. Extrapolate from there or use a time-temp chart to get the time for 20c. Your mileage may vary.

I'll recheck my notes later to reaffirm the time with you.