Quote:
Originally Posted by Dennis
Hi Glob
I think that Par focal is more a property of a range of eyepieces, meaning that when one eyepiece is focused, you can simply replace it with the next one and in theory, the focus should be spot on.
From memory, I don’t think that my TeleVue x2.5 and x5 PowerMates (1 ¼ inch) are parfocal – I recollect having to adjust the focuser when changing PowerMates with either a ToUcam or a DMK CCD camera plugged in.
I have a TeleVue x5 PowerMate in the 1 ¼ inch fitting and in my experience, I have only used it visually on my Vixen 102mm F9 ED refractor a few times, mainly to split double stars.
A x5 PowerMate will convert your 80mm F5 to an 80mm F25 system and you will probably be disappointed with the views?
Cheers
Dennis
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Hi Dennis,
Thanks for letting me know this info.. So I'd probably have to wind the focuser in a bit (I think this is the correct way???

) with the powermate. Also, I wanted to use the high power to resolve double stars, see better planetary detail and improve my lunar observations. The 3x barlow (even though its a cheap one) gives a real improvement to the detail. Bearing in mind that I don't need the rich field property of the refractor for this type of work, do you still think the 5x powermate (or barlow) wouldn't be a good choice?
Regards,
Glob.