Quote Originally Posted by ntenny View Post
Is there anything extremely special about the Spur developer, or is it basically similar to other document film developers like POTA?

Hello Nathan,

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.

Best regards,