Hello Bernard,
the Nikkore on the M series all work very well (the 450mm I have however unfortunately no more).
- Small and light (the 300mm is Copal 1).
- No or barely recognizable CA's (depending on the light situation).
- Color reproduction is very natural.
- For my feeling very nice tone transitions with many details.
- Consistent color reproduction over all M series lenses.
- Sharp when the aperture is open (F9) although it is not as strong as modern lenses.
- Picture circle is huge - 325mm at F22.
About the absolute circle performance, but I cannot make real data.
I can digitally max. (a little bigger) up to 4x5 "stitching. In the area practically no falling edge performance is perceptible for me. As MF body I use the Fuji GFX or the Pentax 645Z. On the Cambo Actus XL, however, I can only use the GFX at this time.
Disadvantage:
- You need a long basic tube on the technical camera and a long bellows at least 20 - 45 cm - depending on the motif distance.
- The GF lenses are all not as backlight insensitive as very modern lenses (despite coating).
- Open aperture F9 (for me no real disadvantage).
Digital I dazzle mostly to F16 or F22. With your MFDB, you can still fade further before the visible diffraction is disturbing.
I have a Scann from the original prospectus of the Nikkore attached for further information.
The T lenses might be interesting for you. With the T lenses you can change the focal distance only by exchanging the rear lens.
I hope the information helps you something further.
I can also make a photo with the 300mm with us in the field for you at the weekend. What would be important to you?
Greeting Gerd