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ZWO T2 Tilter with MPCC iii coma corrector and DSLR

ZWO T2 Tilter Tilt Coma
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Menelaos avatar
Menelaos avatar
Hello guys,

I got myself new equipment and i was having problems with distorted stars in the corners of the images. I suspect that i have sensor tilt since i tried all methods of collimating my scope, focuser is sturdy and looks like it is aligned properly. I could be wrong but the only thing left to try is fix sensor tilt, plus i analyzed my images in astap and it shows tilt so i guess this is it. I use a dslr canon 250d with mpcc iii baader cc. I got myself today a zwo t2 tilter but i have a few questions and looks like new problems to deal with. Do i fit the coma corrector in front of the tilter or the tilter in front of the cc? Also if its the first case then the cc doesn’t have the correct distance from the sensor and if it is the second case then I don’t get in focus at all. This whole situation got me really frustrated and i’m running out of options and money. Anyone know a good solution to this?? 

I’m also relatively new to the community so i would like to say thank you guys for the support its great being here!
andrea tasselli avatar
andrea tasselli avatar
It is in between the MPC and the camera. Camera backspace = 44 mm. T-thread adaptor = 11/12 mm. ZWO tilting adaptor (mk.II) with T-thread adaptor = 13 mm. So basically you are out of luck as you are at least 13/14 mm short. Either you get another CC with more generous backspacing or you get a camera with less back-spacing requirements (not a DSLR). If you're handy with machine tooling you can always recover a Canon lens flange from a wrecked lens at near no cost and screw it to the tilting adapter, which would give you the required 55-56mm of backspace.
Helpful Concise
Philip F. avatar
Philip F. avatar
I would try something like this.  https://www.bhphotovideo.com/c/product/995135-REG/fotodiox_m42_eos_p_pro_canon_eos_camera.html You might need some small shims to get the spacing just right if the tilt adapter isn’t thick enough. Hopefully the tilt adapter isn’t too thick, because then there won’t be much that you can do.

edit: this is another option for tilt. https://agenaastro.com/astrodymium-rotating-tilt-adjusters-for-select-threads.html