After a few modifications of the proposed prototype, I made a version that uses two 50 mm photography objectives from the firm YONGNUO. These objectives are attached to the filter cube using adapters made in-house, and the second objective (that playing the role of tube lens), is attached to the camera using a Bayonnete to C-Mount adapter. The LED is attached using custom-made adapters to the filter cube.

This configuration results in a 1x magnification. I tested it with beads and it gave superb results with very sharp images and good homogeneous illumination. The full sensor of the BASLER acA3088-57um camera is used. We also tried imaging of worms with GFP-labelled head neurons. This also worked, but the images are not particularly bright, and the resolution is limited.

Based on these results, we convened that we can proceed to replicate several times a similar microscope for behavioural studies. Another version for Ca2+ imaging will follow.

To reduce costs and allow easier incorporation of a bright-field illumination, I ordered a set of small tables. I also plan to make a simpler adapter for cooling the LEDs and attach them to the setup based on the design we used in the past.

Left Drawings for the workshop including the table and the canon to SM1 adapter. Right Old prototype of the cooling element for LEDs