Summary

I made this adapter to be able to connect my mobile phone to a telescope for digiscoping (aka afocal photography), this is taking pictures of the eyepiece. I made a large hole in the back of the phone case to be able to remove it easily and also to save some plastic.

Using an inexpensive aluminium T2 camera adapter and any eyepiece that fits inside the adapter you will be able to take nice astro pictures with your iPhone. If you want to take long exposures / pictures of deep sky objects you will also need a tracking device for your telescope.

Please also note that for taking night pictures the default Apple camera app is not great. It is better to rely on a made for purpose app like NightCap or AstroShader.