Lens Thread

[Grillage]

I have a 150 mm Schneider Componon HM APO lens. I need to know what the accessory thread size that it has. I am using a "Zig-Align" system to properly align the lens with the baseboard and negative carrier. I am curious if people find the Zig-Align system accurate. I have used it in the past and it seems okay but I am not sure. Thanks

 

[AgX]

Apo Componon HM 150mm F4

both threads M55 x 0.75

 

[Grillage]

Thank you!!