Adapter for 4x/0.10 Plan N objective to HAYEAR industrial microscope camera -- adapter not working

Currently I am trying to get a 4x objective to work with a HAYEAR industrial microscope camera using a “Microscope Objective lens Adapter Ring C-mount to RMS for Industrial CCD Camera” adapter. The objective threads match up, but the image itself is not going into focus. Is there a way I could get it to work?

It is for a small microscope that I have built to look at animals in a hypoxia chamber box.

What kind of objective? If this is an infinity corrected objective you will also need a tube lens and some distance between the objective, the tube lens and the camera. If this not an infinity corrected objective you don’t need a tube lens but there is still distance expected between the back of the objective and the camera, usually something like 18cm, but I don’t recall exactly.

Hi it is a plan N 4x objective. Marking on the front is “infinity/-/OFN22”. What do you think the minimum distance for a phototube would be? Trying to fit the entire device (camera/stand/light) in a 1-foot tall enclosure.

Looks like an unbranded version of Olympus PLN4X. This objective is designed to use a 180mm tube lens in a infinity microcscope. In my experience optical performance remains high regardless of spacing between the tube lens and objective with Olympus and Nikon objectives so you could put the tube lens near the objective.

If you are trying to make a compact inexpensive system then look into a finite conjugate objective instead. I suspect the ebay part you found is designed for a finite conjugate objective (but also likely has out-of-spec spacing between objective and camera, maybe you can get away with it in many cases). Edmund Optics has a page describing finite and infinity setups.. The finite conjugate setups use RMS threads and most of Olympus’ infinity-corrected objectives also use RMS threads.

My recommendation would be to go out and buy a finite conjugate objective.

Great thank you for the reply, so might an objective like this 4x finite conjugate objective be suitable to use with the microscope camera?