mi-crophot

I'm glad my comment helps somebody who needed. 1.FX and FXA both have the same B4-mount. I have FXA also. 2.Putting a camera on B4-EF mount adapter directly will configure Direct Projection system. This will project small image circle that is not enough to fill full frame sensor. Direct Projection configuration will suit for 1" sensor like Nikon 1 series. For full frame sensor will be needed another configuration.

The keyword is "B4-mount". The flange focal distance is 48mm. B4-mount - Wikipedia I own Nikon Microphot FX and an B4-EF mount adapter to mount my Canon EOS DSLR. And It works. Eyepiece observation and image on the camera sensor are parfocal even if its small image circle was another story. I had struggled similar situation few years ago. So I decided to register for this community to share my knowledge. I hope this will help.