Hi, I've bought a C8 HD hyperstar from opt second hand and I've received a filter adapter with it which as far as I'm aware should be used for backfocus.
Yesterday I tried my first attempt but unfortunately I think I just didn't manage to reach the required backfocus, after checking this further I believe I might've received an adapter that doesn't fit for me?
Here is what the starizona C8 adapter should look like: https://starizona.co...mera-adapter-c8
But this is what I received: https://optcorp.com/...er-celestron-c8
Here are a few more pictures:
Sort of comparison: https://i.imgur.com/Kq2eZGL.png You can see that the bottom of the one on the right is bigger than the one on the left.
I've also found the same here: https://www.highpoin...c8-hsca-c8-cust
Is it possibly a custom adapter? Would love to know what you think. Thanks!