RE: [William Optics] Re: WO GTF81 Accessories for dummies :)
I can’t comment on the eyepieces because I only use my GTF-81 got imaging.
I only have a few very old eyepieces.
As to the Flattener , you are correct you don’t need one because it is built in.
Thanks for the feedback. I think in time I will get more eyepieces, these are just for start (as I can't afford all of them at once). I tried to select the ones for which I found the most positive reviews. The TV 8mm Plossl was reviewed after testing (along other eyepieces) in a CloudyNights document. And there isn't a 7 or 6 mm on this eyepiece.
Anyway, I was looking at a Baader Classic Ortho 6mm - wondering if that is a good choice? I'll have to decide between these two for now.
From what I read here on the forum the GTF81 has an built in field flattener and does not need another one. Can anyone confirm this?
you could buy the UWAN series, the WO 7mm and 16mm. Or consider the Vixen LVW 17 for large field views.
I own the Megrez 90 f/6.9. For fast grab and go observation, I find the 7.5-22.5mm WO Zoom eyepiece is fantastic. However it suffer from small FoV at 22.5mm (42° only), while enought at 7.5mm (65°).
For planetary visions I would not suggest a 8mm Plossl. Take *at least* a 7mm.
Sometimes to see Jupiter I use the UWAN 4mm even thought I think it gives its best on globulars.
In fact it suffer from parassite lights, and the 82° FoV is not necessary.
The 14mm 100° is a good choice. You get a higher powered view but with a FoV comparable to a 17mm. However read the CloudyNights website, someone wrote you can't see the whole 100°; someone tested it on a M90 too. Be careful.
For astrophotogray, the M90 has an evident field curvature. Using the camera adapter only coupled with a DSLR you will be forced to crop your frame a lot because borders are much distorted. Even using the Lens Distortion filter in Photoshop, you can't get soddisfactory results. Best use a field flatterner, even a general purpouse one that sells many dealer (OPT, TeleskopService, and others).