Hello IIS guys and Gals,....
I hope someone can help me here with my problem..Its driving me nuts!!!
Ever since I made my OTA up I have had problems with flexure..(all homemade).
For normal visual use this isn`t a problem but as I made this up basically for deepsky imaging its
rather anoying...
I have attached some pictures of the tube mounting, mirror cell and spider assemblly.
I have rebuilt the secondary since and I don`t think this is a problem as its soo solid. All made
from solid aluminium (has been hollowed out to reduce the weight). Vanes are 20x3mm flat bar while
the centre is 50x20mm round bar. Secondary is siliconed to a similar sized bar cut at 45*.
Tube is rolled 1.6mm aluminium about 20cm dia and welded.
Primary cell is made from 6mm plate aluminium and I have put collimating lock bolts in as well to
stop any movement. Mirror is attached with silicone to 3 polycarbonate disks 2.5mm thick, 30mm Dia
at 40% from centre of mirror. I had soft neoprene blocks to start with but I could really notice
mirror movement in any image over 1 min. so replaced with hard poly.
Tube rings and the support bar have both been reinforced with aluminium ribs and I can`t see them
causing any issues.
Flexure doesn`t seem much af a problem near the meridian like 70* elevation but lower down like 50*
above the horizon I can get only get a few minutes before I get star trailing..
I know it`s not the guidescope setup as well as I use that with my Tv genesis with no problems..
Any suggestions from any of you ATM`ers or imagers would be greatly appreciated and you might save
some of my hair on my head!!!....
Cheers Gary