New VS Old Tri-X Testing REDONE

[scott jones]

Hello again,



I recently posted my test results for the new 320 Tri-x 4x5 sheet film for
ISO testing and development times for N-2, N-1, N, N+1, N+2 developments and
found that the times have increased significantly (more than Kodak suggests
for this worker) and I had trouble even achieving a good N+1 and N+2 development.
The old thread is: here



This posting generated a lot of interesting comments, much of it centered
around capacity problems of the Xtol 1:1 that I was using and perhaps that
is why I was having trouble with the expansions. After thinking about this
for quite some time, I decided to do it all over with this in mind and I am
reporting the results and the improvements I discovered.



The last test was done with Xtol stock that was 3 months old in tightly stoppered
brown bottles. Shelf life is supposed to be at least 6 months, but I decided
to be safe and mixed a fresh batch. My technique is as follows: Xtol 1:1, 68
degrees, Jobo CPP-2, 3010 Expert drum, RPM setting 4, tap water, no pre-wet,
standard stop-fix-wash cycle, densitometer warmed up and stable. My ISO came
out at 320 with a density of 0.10 above fb+fog. My goal for development time
testing was 1.25-1.35 for Zone VIII. N-2 was for moving X to VIII. N-1 was
for moving IX to VIII. N+1 was for moving VII to VIII. N+2 was for moving VI
to VIII.



I rechecked N-2, N-1, and N using the same 500cc 1:1 which should be more
than enough capacity and everything was OK. For the N+1 and N+2 I used a full
1000cc 1:1 which by all figures is a whopping over-capacity for just one sheet,
and WAS able to achieve successful N+1 and N+2 expansions. My conclusion is
that possibly Kodak's figures about capacity are overly optimistic with expansions
and for this "new" film. I am going to do only a few sheets at a time in a
full 1000ml of 1:1 Xtol. Also of question in my mind is whether the 3010 Jobo
expert drum really does mix fluids from compartment to compartment as they
claim or whether each of the five compartments somewhat sequesters 1/5 of the
fluid and thus this would contribute to capacity problems. Figuring all this
out would be way too much testing for me, but perhaps others would be intrigued
enough to do capacity/volume testing...



Thanks for all the previous comments and here are the final times so you can
see what the new development times for this film look like in one darkroom:

<table width="256" border="1">
<tr>
<td width="68">N Factor </td>
<td width="74">Old Tri-X </td>
<td width="92">New Tri-X </td>
</tr>
<tr>
<td>N+2</td>
<td>10:15</td>
<td>15:30</td>
</tr>
<tr>
<td>N+1</td>
<td>8:10</td>
<td>11:30</td>
</tr>
<tr>
<td>N</td>
<td>6:45</td>
<td>8:30</td>
</tr>
<tr>
<td>N-1</td>
<td>5:20</td>
<td>7:10</td>
</tr>
<tr>
<td>N-2</td>
<td>4:15</td>
<td>5:45</td>
</tr>
</table>

ScottJonesPhoto.com

[David A. Goldfarb]

Thanks for the new tests. I'm not an Xtol user, but those are interesting results nonetheless.

[bob moulton]

Scott; How many sheets of film did you process in the 3010 at a time? As I read your posting, I understand you used 1000cc for one sheet of 4x5 at N+2. But what about the other parts of the test?

[Tom Westbrook]

Thanks for the new tests. It's great you could get N+2.

I got a CPP recently and have been trying to come up with an EI for 100Tmax in TmaxRS 1:9 and sympathize with the "too much testing" feeling.

I feel that the drums do exchange fluids just fine, so I wouldn't worry much about that. You'd have to rotate the drum way faster than the CPP is capable of to keep the soup from moving around.

FWIW, I talked recently to a Jobo rep about using less than the full quantity of sheets in an expert drum. They said:

Spacing of the film really doesn't matter for varying the amount of film you are running. What is important is keeping
the ratio of developer to film within 25ml per sheet per run. In other
words, if you run 6 sheets of 4x5 film [in a 3006 drum] using 1000ml of chemicals, it works
out to 167 mls per sheet. So if you want to run 4 sheets on the next run,
you would want to keep the ratio between 142ml and 182 mls per sheet. So
for 4 sheets you would need between 568 and 728 ml per run (570-730 for
ease of measuring) to keep the results consistent. I always recommend that
you run at least 2 sheets per run. Running just one sheet will usually
cause a slight jump in contrast and density.

Anyway, thanks for posting your numbers. Tri-X in Xtol 1:1 is one of my favorite combinations and I'll use your numbers as a starting point.

[scott jones]

Hi all,

to answer Rob's question:

N+2, 1 sheet, 1000ml

N+1, 1 sheet, 1000ml

N, 2sheets, 500ml

N-1, 1 sheet, 500ml

N-2 , 1 sheet, 500ml

I wanted to make sure that capacity was NOT a problem with this test.

[Sal Santamaura]

Jobo's conversation with Tom indicates to me they're expecting some degree of exhaustion; why else would maintaining the same developer:emulsion ratio be needed for consistency? On the other hand, Scott's latest round of tests is predicated upon a huge "overquantity" of developer to specifically avoid exhaustion.

We probably can't conclude whether Scott's success this time indicts the Expert drum for insufficient mixing between chambers, Xtol for having less inherent capacity than Kodak claims or some combination of the two in his first trials.

[Tom Westbrook]

Yes, Sal, it is sort of odd. I suspect a fair amount of this is just superstition, or CYA for Jobo, and isn't really based on any hard testing. Or if it is, the effect is so minor as to not be worth worrying about. I plan to just use Anchell's overkill formula (250mm stock per 80sq in) and let it go at that, though I might trim that back to 200mm/80sq to satisfy my cheapskate side.

One interesting thing I noticed in this Jobo Quarterly issue was that too slow rotation can lead to insufficient mixing within the film tubes in an expert drum. They recommend 50rpm (or a '4') for expert drums. It's interesting that in the same issue, John Sexton says he uses a setting of '3 1/2'. So, I'd guess this isn't all that critical, either.

[Sal Santamaura]

Some more interesting Jobo information. I was going to do this in HTML and include a link, but, even though Jobo's site still has a link to

"CPA and CPP Speed Settings for old and new motors,"

that page has not been accessible for the last two days. Fortunately, I printed it three months ago and can refer to a hard copy. It says that all CPA/CPP processors with serial numbers greater than 22000, or that have been upgraded with the new (93016) rotation motors, provide different speeds for given dial settings than do those with the old motors. Here are the data:

Old 0: Off New 0+: 25 r.p.m.

Old F: 25 r.p.m. New F: 46 r.p.m.

Old 3: 40 r.p.m. New 3: 70 r.p.m.

Old 4: 50 r.p.m. New 4: 86 r.p.m.

Old P: 75 r.p.m. New P: 86 r.p.m.

Old 6: 78 r.p.m. New 6: 86 r.p.m.

Old 7: 80 r.p.m. New 7: 86 r.p.m.

It goes on to say that the speeds are approximate and variations of 10-15 r.p.m. will not show up in your processing results.

That 1994 Jobo Quartely was before the motor change, so a recommendation of 50 r.p.m with Expert Drums would have correlated to speed setting 4; Sexton's 3 1/2 probably resulted in around 45 r.p.m. Using late-model or motor-upgraded machines would require settings of F or very slightly above F to achieve the same 50/45 r.p.m. rotation speeds.

So Scott, which rotation motor does your CPP-2 have, i.e. what rotation speed was actually used in you tests?

[scott jones]

Sorry for the delay in responding. I have #23851 which is therefore a machine with the newer motors and I used the recommended setting of "4" with the 3010 expert drum. With the data you have presented it looks like there is no difference in settings 4, P, 6 and 7 with the new motors and that the rpm is quite high! I wonder how this correlates with their instruction manual which suggests setting "4". I think I will call Jobo...

[Sal Santamaura]

No problem with the delay; I hope it means you were actually making pictures and *using* your processor (something there's usually not enough time for here)!

The instruction manual was probably not updated for the new motor, and I suspect they really mean to suggest "F" for black and white film in Expert drums.