The WO-132 does look ok on paper, but agree, putting a large format CCD camera behind it is the real test. I saw the 132 while at an astrophotography conference in Antwerp, Belgium. Its a monster scope. Looks very impressive.
http://www.williamoptics.com/prod_te...32/chrommb.gif
http://www.williamoptics.com/prod_te...32/sp_spot.htm
Traditionally, the WO-110 and WO-132 uses either TEC or TMB lenses. The TEC objectives are impressive, but potentially difficult to obtain. Not sure if its is possible to specify the type of objective. Perhaps luck of the draw.
Indeed, the TOA-130 would be a preferable option, but make sure its the TOA-130F (A$9,107) with the 4" focuser, not the TOA-1
30S (A$7,862) with the 2.7" focuser. No point spending this sum of money only to limit your image circle for large format CCDs. I'm seriously thinking about the TOA-130F, even though I've put my name down on the "new Q" (new version of the FSQ-106). Takahashi still haven't released any specs on the new Q. It is anticipated that the new Q will cost around the A$7,800 mark, but will not start shipping until April '07. Not sure if I can wait this long. So it’s only approx $1k more to get the TOA-130F, but then would also need to purchase a field flattener (35 flattener A$530). I'm a purist for flat fields, can't get enough of them. The flatter the better.
This then adds a twist. The TOA-130 has a focal length of 1000mm, this is a nice focal length for many deep sky objects, however when you at the flattener the focal length changes to 758mm. So, if the new FSQ is similar to the old (around the 530mm), there is not much difference between the two. The FSQ would operate at its native focal ratio of F/5 and the TOA-130F with field flattener at F/5.8, so again not much difference. The FSQ does not need a field flattener due to its quadruplet modified petzal design. Hence you can be assured of an 88mm image circle. I can't imagine the TOA field flattener would add any form of vignetting. Natively, the TOA has a 92mm image circle, but not sure what the flattener would do. Anyone out there willing to share their experience with a TOA-130 field flattener??? Perhaps you can use the 67 field flattner (A$950) which would resolve any concerns.
Of course, this is all fine if you intended to stick to small CCD chips like those in the ST7,8,9 and 10. But using a large format CCD like in the STL11k or STL6303E you’re bound to experiencing vignetting and field curvature problems. Nothing some sky flats and image processing can't take care of, but its wise to mitigate these in the first place to minimise the processing time.
The search continues...
