JayPea

Hi, I thought some might be interested in a simple DIY adapter to connect to Nikon AF-S G lenses, in my case to an uncooled ZWO camera. As I’m looking at using my Nikon G lenses but the catch is they don’t have the aperture ring to manually open the aperture when not used on a Nikon camera. I’d seen several people use attachments based around the QSI Nikon adapter with the manual aperture control but at $250/£198 it was bit over my budget. I’d done the usual searches but I couldn’t be sure exactly what bits to buy to guarantee I could just screw on a ZWO to a Nikon G lens and it would work, i.e. the correct spacing and would open the aperture. I already had a cheap (only £5.99 + £1 p&p off Amazon) extension tube set made by Fotga. This was the only one I found with the manual aperture control specifically for a G lens. I also had a few of the 1.25 to T2 adapters spare. So I simply took the Nikon lens mount end from the extension tube set and slipped it over a 1.25 tube using a big doughnut spacer to fill the gap between the diameters and set its length to make the correct back focus required. My final assembly measured 34.4mm depth where I need 34.0 but it appears to focus OK so I haven’t bothered removing 0.4mm. I did cut back the 1.25 tube a bit shorter so I could screw in a filter and still clear the lens mount and it’s all held together with some grub screws. It’s solid when on and easy to remove. It also works well as an adapter for turning the lenses into spotting scopes/telescopes if you slip in an erecting eyepiece. I ordered a replacement Fotga tube set but I got a note back from Fotga saying they’ve sold out and it would not be replenished. But they do a few Nikon G to other mount adapters that look to have the manual aperture control mount you need (I’ve ordered the Nikon to Micro 4/3 adapter, happy to risk it for £8). I think you need the (G) ones, not the (AI) ones. Now my next plan is to actually pull my finger out and get a ZWO camera as I only borrowed one to see if it works! (thanks john78). Cheers, John