Fomapan 400, D23 development times, etc

bryans_tx

Subscriber
Joined
Sep 7, 2016
Messages
175
Location
North Texas
Format
Multi Format
Hello,
What advice can you guys offer for developing Fomapan 400 in D23 ?
I checked the massive development chart, but I am unsure about the agitation for the 1:2 , 20 minutes suggested by the chart, as there were no notes.

thanks,
Bryan
 
OP
OP

bryans_tx

Subscriber
Joined
Sep 7, 2016
Messages
175
Location
North Texas
Format
Multi Format
Yes hopefully exposed for Box speed of 400.
Not rotary.

Patterson Tank.

If I go with 1+1 at 13 minutes intermittent, what do you suggest for the intermittent agitation cycle ?

thanks VERY much!
 

Andrew O'Neill

Moderator
Moderator
Joined
Jan 16, 2004
Messages
11,803
Location
Coquitlam,BC Canada
Format
Multi Format
bryans_tx said:
Yes hopefully exposed for Box speed of 400.
Not rotary.

Patterson Tank.

If I go with 1+1 at 13 minutes intermittent, what do you suggest for the intermittent agitation cycle ?

thanks VERY much!
Click to expand...

I always agitate 5 sec every minute, regardless of film type.
 

M-88

Member
Joined
May 2, 2018
Messages
1,023
Location
Georgia
Format
Multi Format
Bear in mind that actual speed of this film is somewhere around 250, not 400, so exposing and developing it at EI400 is a slight push. I got best results from Foma 400 when exposed and developed for EI200.

It's also one of those films I will never buy again.
 

traveler_101

Member
Joined
May 31, 2013
Messages
87
Location
Oslo, Norway
Format
35mm RF
M-88 said:
I got best results from Foma 400 when exposed and developed for EI200.

It's also one of those films I will never buy again.
Click to expand...
I’ve wasted a lot of time with it, no more. One time I got good results was shooting at 200 on a heavily overcast morning developed in D-76 1+1
 

M-88

Member
Joined
May 2, 2018
Messages
1,023
Location
Georgia
Format
Multi Format
traveler_101 said:
I’ve wasted a lot of time with it, no more. One time I got good results was shooting at 200 on a heavily overcast morning developed in D-76 1+1
Click to expand...

Oh well, it would have been easier, had they written an actual sensitivity on the box, not 400. Foma 400 is the worst of their bunch. 200 is fine and 100 is the best. Abut even that one performs with random precision.

I still have some good shots from Foma 400, but success to fail ratio is too high.

Edit: too low, I mean.
 
Last edited:

albireo

Member
Joined
Nov 15, 2017
Messages
1,306
Location
Europe
Format
Multi Format
Foma 400 in 120 is one of my favourite films. It needs to be exposed and developed with respect for best results, and I've found following the manufacturer's spec sheets for a target gamma =~ .58 gives me great reproducible negatives optimised for my workflow.

It looks awesome in Fomadon LQN, Fomadon Excel expecially, but I've gotten some great results with it in D23 1+1 too.

Ever since fine tuning Foma 400 I just can't get back to run-of-the-mill 400 ISO film like Hp5 or TRI-X. Foma 400's spectral response is just unique. Gorgeous film, I burn some 10 rolls per month in my Fuji GW690.
 
Last edited:

pentaxuser

Member
Joined
May 9, 2005
Messages
19,683
Location
Daventry, No
Format
35mm

albireo, what film speed do you expose it at? Thanks

pentaxuser
 

albireo

Member
Joined
Nov 15, 2017
Messages
1,306
Location
Europe
Format
Multi Format
pentaxuser said:
albireo, what film speed do you expose it at? Thanks

pentaxuser
Click to expand...

Hi Pentax


Page 2, first column of graphs. I will generally interpolate the graphs for a target gamma of .58 to reach a starting point. So eg 200 for D76, 250 for Excel, 250/320 for LQN. Then I will adjust based on how I meter and if I feel the contrast of the scene might require an amount of pulling or pushing.
 
Last edited:

pentaxuser

Member
Joined
May 9, 2005
Messages
19,683
Location
Daventry, No
Format
35mm

Thanks I wonder if you can help me a little more here with how to read the graphs If we take D76 at 20C then is the case that the top curve indicates the film speed at various development times so to get to 200 the time is just over 7 mins?

How do I work out the Gamma at that development time? Do I just go straight down from the 200 speed? If so this gives me a Gamma of about 0.62 and not 0.58 but I may be making the wrong assumptions about how to read the graphs

Thanks

pentaxuser
 

albireo

Member
Joined
Nov 15, 2017
Messages
1,306
Location
Europe
Format
Multi Format

Hi

The way I do it is to *start* from the gamma I wish to achieve. See example below for Fomadon LQN.

In this example, let's say we wish to aim for a gamma =~ .7 (this is extremely high contrast, way too high for scanning, and I'd imagine also high for wet printing - it's just an example).

Follow the path traced by the red arrow. We start at (1), on the vertical axis on the right. We trace a horizontal path to intersect the gamma curve. At the intersection (2) we'll trace a vertical line to intersect the 's' curve at (3). Starting from (3), a vertical line down towards the horizontal axis will indicate a dev time estimate, whereas a horizontal line towards the vertical axis on the left will indicate the film speed achieved.

For the example above, if we are happy with a gamma =~ .7, we will achieve a speed of 320 and development will require approximately 11 minutes.

 

pentaxuser

Member
Joined
May 9, 2005
Messages
19,683
Location
Daventry, No
Format
35mm
Thanks albireo. Based on what you have described I think I got it correctly in my assumptions but I got the Gamma as 0.62 rather than 0.58

Your objective of 0.58 seems low compared to the contrast that Ilford and Kodak suggest but of course each of those companies use a difference index( Gbar and Contrast Index respectively) from that of Gamma and in turn each one is different from the other

I have asked what the relationship is between GBar and C.I. in the past but not between Gamma, C.I. and Gbar. So can I ask you what it is i.e. in Gamma terms what does a Gamma of 0.58 equate to in both the other terms?

It may be that a Gamma of 0.58 is right for scanning but not ideal for darkroom printing where it should be higher and is what I do but again I don't know.

So you or anyone with answers to these questions is welcome to respond

Thanks

pentaxuser
 

albireo

Member
Joined
Nov 15, 2017
Messages
1,306
Location
Europe
Format
Multi Format
pentaxuser said:
I have asked what the relationship is between GBar and C.I. in the past but not between Gamma, C.I. and Gbar. So can I ask you what it is i.e. in Gamma terms what does a Gamma of 0.58 equate to in both the other terms?
Click to expand...

The gamma is the measure of the slope in the linear portion of the curve. I believe that the CI is the average slope based on measurements taken at several points of the curve, according to some criterion. I am not familiar with the other metric you mention. I'm sure someone else will chime in.
 

pentaxuser

Member
Joined
May 9, 2005
Messages
19,683
Location
Daventry, No
Format
35mm

Thanks. Yes it is important that somebody does since otherwise reading a Foma graph with Gamma does not have a good comparison in Kodak or Ilford terms

It's a bit like someone who only ever has used Fahrenheit using a chart in Centrigrade and trying without knowledge of the relationship to compare what that means in terms of Fahrenheit

pentaxuser
 

removedacct2

Member
Joined
May 26, 2018
Messages
366
I got a FED-NKVD with defective rangefinder. I wanted to check the alignment of the lens, so I used a Blix external RF in order to focus with the distance scale of the lens, at different close range distances, 1m, 1,25m 1,5 2m, etc. Did that indoors, used two studio lamps, and load a short strip of Fomapan-400, metered at 400, in order to take few pictures with the old FED lens at 3,5 4,5 6,3 at 1/20s.
Just a test strip with 6 frames, and I was lazy to mix a developer, so I just picked a bottle of D-23 with 5g metol instead of 7,5g that I use with some contrasty 8x10 sheets and that has been replenished 35 times.
I didn't bother at all about the results besides checking the exactitude of the lens scale distance.

12mn, 1 mn constant agitation, then 10s every minute. With sheet film I do a 2nd bath with 10% borax, but for this fast little lens test I didn't.
So:




 

removedacct2

Member
Joined
May 26, 2018
Messages
366
this time I tried D23 for itself with some Fomapan-400 35mm

Very sunny day, I was lazy to use a spotmeter , instead just the average metering of the CdS in a Ricoh Singlex II, with some 70's zoom lens 35-105mm

I metered for iso 250. Didn't follow development time provided by Massive Dev Chart. Instead, I opted for 10 mn of replenished D23 I mixed in june 2022 and replenished over 35x with DK25-R. 1st mn constant agitation, then quite energetic: 5s every 30s, then 5 mn constant agitation with 10% borax. I usually use two baths with sheets. not sure it has a real effect on small format.


some pictures, with a bit at 100%:
























 
You must log in or register to reply here.
Menu
Log in
Register
Cookies are required to use this site. You must accept them to continue using the site. Learn more…