Response to EFKE ISO 25 film- spectral sensitivity change?

The German distributor (Fotoimpex Berlin) said Fotokemika would use the original Adox emulsion recipe or all three films (KB25, KB50, KB100). The spectral sensitivity curves on the data sheet showed that KB25 and KB50 are not as sensitive for red light as KB100 and other standard panchromatic b&w films. I checked it by taking a deep red filter (no 29) and there war indeed a nearly blank negative (the filter factor for no 29 would be about 100 to 200). So I would consider KB25 and KB50 (resp. R25 and R50) as orthopanchromatic and think they behave as the former KB14, KB17, and KB21 films. I

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