Setting CCD rotation for imaging

[festoon]

Any tips as to how you rotate your camera such that is orthogonal with RA/DEC in e.g. portrait - but keep the back focal lenth the same. When I attach my CCD with T2 extensions the camera is at the correct back focal distance from the lens (Samyang 135mm) but the camera is rotated at an arbritary angle dependent on where the T2 thread mates to the ccd.

[Stuart1971]

57 minutes ago, festoon said:

Any tips as to how you rotate your camera such that is orthogonal with RA/DEC in e.g. portrait - but keep the back focal lenth the same. When I attach my CCD with T2 extensions the camera is at the correct back focal distance from the lens (Samyang 135mm) but the camera is rotated at an arbritary angle dependent on where the T2 thread mates to the ccd.

Hi,

Yes this is an issue with fully screwed on accessories, I had this same issue, so bought a 2” Baader clicklock, so then had 2” nosepiece on the camera and could alter within the clicklock...

Then on my newer Tak FSQ85 it came with a camera angle rotator, which are available for other scopes...but not cheap... HTH 👍🏼

[festoon]

Thanks @Stuart1971

Glad I'm not the only one who's come across this issue

[Stuart1971]

2 minutes ago, festoon said:

Thanks @Stuart1971

Glad I'm not the only one who's come across this issue

It’s a common issue, we are certainly not alone...?

If you do a search for camera angle adjusters, you may get some ideas.... 👍🏼

[festoon]

Superb @Stuart1971. Searched camera angle adjusters with T2 and found this. Thank you

https://www.teleskop-express.de/shop/product_info.php/language/en/info/p5547_TS-Optics-T2-Thread-360--Rotation-and-Quick-Changer---5-5mm-short.html

Looks like this might be useful to have in my T2 extenders.

I wonder does anyone have any experience of this particular adaptor...is it worth getting.....and if it works well?

[callump]

6 minutes ago, festoon said:

Superb @Stuart1971. Searched camera angle adjusters with T2 and found this. Thank you

https://www.teleskop-express.de/shop/product_info.php/language/en/info/p5547_TS-Optics-T2-Thread-360--Rotation-and-Quick-Changer---5-5mm-short.html

Looks like this might be useful to have in my T2 extenders.

I wonder does anyone have any experience of this particular adaptor...is it worth getting.....and if it works well?

I was just hunting for a link to this - yes, I have one, and it works really well... It's nice low profile, useful if your back focus or working distance is short.

Callum

[festoon]

2 minutes ago, callump said:

I was just hunting for a link to this - yes, I have one, and it works really well... It's nice low profile, useful if your back focus or working distance is short.

Callum

Thanks @callump

Good to hear it works well.

For me I'm very limited in space. I've a Samyang 135mm (44 mm flange focal distance). Geoptik EOS to T2 adaptor which takes up 19mm, and 17.5mm distance from front of CCD to sensor. So that only leaves me 7.5mm spacing for any extra pieces e.g. a rotator and filter wheel/changer. If I use 2mm filters this adds 0.66mm to the flange focal distance, so I have 8.16mm available for a rotator and filter wheel. Which if I use 5.5mm for the rotator leaves me with a filter problem

Only other option would be ro replace the Geoptic EOS adaptor but I find this works very well.

[Stuart1971]

1 hour ago, festoon said:

Superb @Stuart1971. Searched camera angle adjusters with T2 and found this. Thank you

https://www.teleskop-express.de/shop/product_info.php/language/en/info/p5547_TS-Optics-T2-Thread-360--Rotation-and-Quick-Changer---5-5mm-short.html

Looks like this might be useful to have in my T2 extenders.

I wonder does anyone have any experience of this particular adaptor...is it worth getting.....and if it works well?

Yes, that’s the sort of thing I was referring too, look on Amazon too, as there are some on there....and cheaper...