Quote:
Originally Posted by Chippy
Hi Glob,
Unfortunately its cloudy in Sydney tonight - so no GRS viewing :-(
It's mainly trouble with focus on some of my combinations. Generally OK with my 8" F6 dob but not so good with shorter focal length dobs (eg. not enough in-focus with a 16" F4.5 dob). Also won't come to focus with my binoviewers on a 4" F7 refractor (close but no cigar!). I actually can't remember all of the combinations that work and don't to list. Some of them just miss or are borderline if I fiddle with EP placement. Its possible that you wouldn't have the same problem with your scopes.
If it comes to focus the views are generally OK, but not as clean as with the 2" 2x ED GSO barlow IMO (which doesn't have the focus probs either). The 2" is a good barlow - just a little heavy at times.
Now that TV prices have come down a bit I'm considering whether to get a 1.25" Televue 2x barlow for $119... or for a bit more a powermate... hard to know what is best for visual. I've read conflicting reports.
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Hi Chippy,
Thanks for the advice. I think I can see what you've been experiencing, the focus knob hits the stop and won't go in any more to achieve a focused image. This was something I'd been concerned about happening too. Maybe I need to try at the shop before I buy???
I was thinking that the bigger 2" barlow probably works better for you because you're using the middle part of the field and so are not getting any edge effects from it. Anyway, for me, the 2" would be a weight problem, so I can't go down that shopping pathway.
Regards,
Glob.