AM-Microscope/DSLR tube

thingiverse

This is a connector for a telescope Barlow lens DSLR adaptor to be fitted to an AMScope microscope! Why? Well, the 32mm telescope 2x adaptor can be bought for under £14, whereas the adaptors for a microscope are around £90! The optics are the same, quality, just the diameter is different. This tube has been tested on these two items: https://www.amazon.co.uk/gp/product/B004QEFO1Q/ https://www.ebay.co.uk/itm/2X-Barlow-Lens-1-25-Multi-Coated-Metal-for-Telescope-Eyepiece-T-Adapter/153125301171 The microscope is an AmScope T490B 40X-2000X full-size professional trinocular lab biological compound microscope, and the 32mm Barlow lens is for a standard telescope eyepiece fitting - screwed into a T2 adapter that locks on to the camera's lens mounting. I used a Canon 7M Mark 2 - though any camera can be fitted to the relevant T2 ring adaptor. IMPORTANT! Sanding down the top inside of the tube: The tube prints about 1mm too tight, this is so the top part of the inside can be sanded down with some fine sandpaper. This enables you to get a really snug fit with no shaking or sideways movement. I used a 1" square, and wrapped it around two fingers, then gently sanded away. You need to remove VERY LITTLE to get a proper fit when dealing with circumferences! So check your progress every couple of minutes so you don't make it too loose. The washer: This sits between the camera and top of the tube - to fine tune the focussing. The washer is to fine-tune the focusing. I've printed the tube about 1.5mm too short, to handle the differences with 3D printers and microscopes. The idea is, you focus accurately through the eyepiece, then use "live view" on the camera zoomed in (the 7D mark 2 can do 10x) to get a clear view of any focus issues. Gently twist and lift the camera out of the tube (or just lift if you made the tube too loose!) until the camera live preview is sharp. Measure the gap between the top of the camera Barlow lens case and the tube... in my case it was 1mm... and print a washer of the right height. If you change your camera in the future you can re-adjust this as needed. I'm going to use a small dab of glue to keep my washer in place.