Great info! Might have to give your combo a try!
Great info! Might have to give your combo a try!
Is there anything extremely special about the Spur developer, or is it basically similar to other document film developers like POTA?
Have you compared Copex Rapid and Spur to Ilford PanF+? You mention that you've used it but in your comparison above you only compared it to FP4+, which I must say enlarges impressively to 16x20" from 6x7 with no grain I can see in the prints. PanF+ 135 enlarges effortlessly to 11x14" with great sharpness and no grain I can see so obviously I'll have to try it out to 16x20".
the Spur developers for microfilms and Technical Pan films are special and have nothing to do with other document film developers.
It is a completely different and unique technology (called "inkorporierte Verschleierung").
With this technology much higher film speed, better resolution and a more homogeneous development is possible.
Spur is doing research in this field for more than 20 years. It's their core competence.
That's the reason why other brands are using this competence as well, e.g the Rollei ATP DC A/B developer for Rollei Advanced Technical Pan (ATP) film is made by Spur,
as well as the Adox Adotech developer for Adox CMS 20.
By the way, I am using the Agfa Copex Rapid, developed in Spur Modular UR New combination as well and can completely confirm Film-Nikos results.
I am very satisfied and can highly recommend it.
Performance of Copex Rapid with Modular in 35mm is indeed better than Rollei RPX 100 and Ilford Fp4+ in 4,5x6 and 6x6. I have tested it several times.
Finer detail and higher resolution with the Agfa Copex Rapid.
To keep a visible advantage with 4,5x6 and 6x6 compared to 35mm Copex I have to use Ilford Delta 100.
Henning, whats your experience with Copex in Modular UR regarding blocked highlights? One thing that really drove me away from CMS20 in Adotech is the fact that there is simply no headroom in the lights. If you want to burn in a sky you end up with a grey area instead of details.
Huge advantage for the Agfa film, no chance for Ilford. Really big difference in sharpness and resolution.
For the comparison with medium format 6x6 I have chosen 100 - 125 ISO films because I want a comparable speed.
With ISO 40 in 135 I have a comparable speed to ISO 125 in 6x6.
An example to explain:
With 135 40 ISO film I meter for example 1/250 and f4, using a normal 50mm lens.
With 80mm lens on 6x6 I have to stop down about 1,5 stops more to get the same depth of field compared to 135 format with 50mm lens.
I get f5,6-8 at 1/250 in 6x6.
To compensate for stopping down I need film with ISO 125.
So with 135 and 40 ISO I have 1/250s and f4.
With 6x6, same depth of field, same shutter speed, I have to use 1/250s and f5,6-8 (the half stop between it) with an ISO 125 film.
In both cases I have comparable speed and depth of field.
That is the practical reason why I compare the ISO 40 Agfa Copex Rapid / Spur Modular to my ISO 100 - 125 films which I am using in medium format.
In normal outdoor shooting conditions ISO 40 in 135 and ISO 100 - 125 in 6x6 are equivalent concerning shutter speed and depth of field.
While acknowledging that we're talking about someone else's proprietary "secret sauce" here, I wonder if it's possible to discern anything about what this description really means. In some sense all development is the same---activated grains get reduced to metallic silver---so I'm a bit sceptical of a phrase like "completely different and unique technology" without knowing what aspect of the process the difference relates to. Is this stuff known, or is it all Spur's secret?
I think SPUR has done a great job for the 35mm ATP1.1 ; CMS20 and Copex version films. However for the 120 roll film versions it is very difficult to get equal developed negatives without "Schlieren". What I have understood is that SPUR is still working on this problem with a variant of the ATP-DC A1/B developer (ATP-DC A2/B) and Modular UR with an extra part.
If I look at my 35mm Leica negatives with ATP1.1 and the ATP-DC developer they can match my M645 with Fomapan 100 or RPX 100 without problem. However in 6x7 I prefer my larger format negatives.
So it would be nice to have an equivalent system for 120 roll film.
Separation of highlight detail is on the same level as conventional films in standard developers. No difference here, easy to print.
For CMS 20 I am using Spur Modular UR New with Part A2 and B (Part A1 is for Agfa Copex Rapid; Part B is identical and can be used for both films).
With this combination I achieve a better curve shape. I expose for ISO 4 - 5 and develop 5 minutes (instead of 6,5 minutes given in the data sheet). So I get the best curve shape I have ever got with this film. Linear curve from Zone I to VII (very good shadow detail), from Zone VII to X the curve flattens, but not as strong as with Adotech (better highlight separation, but not optimal yet).
If you want high effective speed for handheld photography and a normal characteristic curve with very good shadow detail and highlight separation, then you will be satiesfied with the Agfa Copex / Modular combination.
It's medium format quality (benchmark: conventional films with cubic chrystals like FP4+) with 35mm.
If you need even higher resolution and finer grain (almost no grain), can accept compromises with the curve shape, and your shooting situation allows a tripod, then the CMS 20 / Modular (with part A2) is a very good option (a friend of mine and me have compared CMS 20 35mm with Adox CHS 100 in 4x5", and CMS 20 has shown better detail rendition).
There is no free lunch ;).
They are indeed clearer looking than with conventional films, because both Agfa Copex Rapid and CMS 20 have a clear base. I like it, because it makes judging the negatives a bit easier (that is a personal preference by me, of course, other photographers may see this different).
As a photographer I am not so much interested in how a technology is called, I am interested in whether it works. And in this case it works very well, and better than other developers (at least to my experience ;)).