Want to switch out the field diaphragm on a Zeiss PM3

[tlansing]

I recently obtained a Zeiss Photomicroscope III and want to switch out the plastic field diaphragm (picture 1) with the metal field diaphragm shown in picture 2. It seems like this should be pretty simple, but before I do it I want to check with the experts here if there are any particular pitfalls to avoid or things to consider (ie, if I swap one for the other do I have to do any alignment of the new field diaphragm?). Thanks in advance for your help.

Tim

Picture 1.jpg (35.37 KiB) Viewed 781 times

Picture 2.jpg (17.57 KiB) Viewed 781 times

[Hobbyst46]

1. I do not know about the PM2/3, but in the Standard GFL, the attachment of the field diagram unit to the base varies slightly. Sometimes there are two lobes for small bolts that lock the unit into the base from below (from the inner side of the base) or there are none, so the unit is just inserted into the base - either by accident or by purpose.
2. Prior to the switching, I would verify that the field diaphragm opens and closes smoothly, under very light finger pressure, since if not, it is much easier to fix it when the unit is out of the base.

[Charles]

Yes, they are easy to change out. I changed out most of my plastic field diaphragms with metal ones.