Camera, auxiliary lens and focus distance

[deuslunus]

Hello and apologies if my question is stupid, but I have the following problem : I own a stereomicroscope and I wanted to connect a video camera and monitor to observe the objects directly on the monitor. I bought this camera
https://s.click.aliexpress.com/e/btl0Rycg

And this C-mount adapter
https://www.optics-pro.com/camera-adapt ... 2-/p,47718

When I'm using an auxiliary lens like 0.5 or 0.3, I am not able to obtain clear picture on the monitor, because I cannot focus it. If I am using the camera without the auxiliary lens, I don't have this problem. I tried to adjust the focusing ring of the C-mount, but it is not able to compensate this difference. I have to raise the microscope really high or to lower the objects really low in order to have focused picture. Do you have any idea how will I be able to change this? Thank you very much for your advices!

[MichaelG.]

When I'm using an auxiliary lens like 0.5 or 0.3, I am not able to obtain clear picture on the monitor, because I cannot focus it. If I am using the camera without the auxiliary lens, I don't have this problem. I tried to adjust the focusing ring of the C-mount, but it is not able to compensate this difference. I have to raise the microscope really high or to lower the objects really low in order to have focused picture.

Not a stupid question at all ... but perhaps not very clearly stated

When you say "When I'm using an auxiliary lens like 0.5 or 0.3 ..."
do you mean an auxiliary on the microscope objective, or on the camera adapter ?

If you mean an auxiliary on the microscope objective: Such an increase in working distance is to be expected.

MichaelG.

[Hobbyst46]

I'm guessing that the 0.5X and 0.3X lens are parts of the camera kit.
If the camera can be inserted into one of the two eyepiece tubes, instead of connection via the C-mount adapter to the phototube, perhaps fitiing it within the eyepiece phototube, with the reduction lens included, will aid to identify the source of the problem.

[deuslunus]

When you say "When I'm using an auxiliary lens like 0.5 or 0.3 ..."
do you mean an auxiliary on the microscope objective, or on the camera adapter ?

If you mean an auxiliary on the microscope objective: Such an increase in working distance is to be expected.

On the microscope objective. I know that the working distance would increase, but when the image is on focus through the eyepieces it is not on the monitor and I can't make it sharp even when I am rotating the focusing ring of the C-mount adapter. Any suggestions how to fix that. Really appreciate your help.

[Scarodactyl]

Without the auxiliary is the camera in focus when the eyepiece is?

[MichaelG.]

When you say "When I'm using an auxiliary lens like 0.5 or 0.3 ..."
do you mean an auxiliary on the microscope objective, or on the camera adapter ?

If you mean an auxiliary on the microscope objective: Such an increase in working distance is to be expected.

On the microscope objective. I know that the working distance would increase, but when the image is on focus through the eyepieces it is not on the monitor and I can't make it sharp even when I am rotating the focusing ring of the C-mount adapter. Any suggestions how to fix that. Really appreciate your help.

As Scarodactyl indicates ... You first need to check the performance without the auxilliary lens, to 'baseline' things.

In the hope that [for whatever reason] you need more camera extension ... C-mount extension rings are available quite cheaply: 5mm is a standard requirement to match-up cameras with CS mounts.

>>> https://www.ikegami.com/cb/products/pdf ... smount.pdf
>>> https://www.ebay.co.uk/itm/110882002221

MichaelG.