Flushed with (relative) success re. my Lunt LS50THa,
I was wondering if it were possible to stretch things...
Or more specifically, does anyone have a functioning
Barlow method that works with the limited in-focus?
I got some sort of image with a budget Skywatcher
Barlow by detaching the front element and letting it
drop within the default eyepiece holder. But...
Anyone have a nicer solution? A standard Barlow?
A Baader (I like their eyepieces) Barlow? Teleview
PowerMate 2.5x? How far could you push things?
Barlow-ing the Lunt LS50Tha?
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Re: Barlow-ing the Lunt LS50Tha?
Try using the skywatcher barlow by unscrewing the nosepiece and screwing it to the front of the blocking filter. I reckon you'll have newtons rings with the TV 2.5x, they're not the best for solar.
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Re: Barlow-ing the Lunt LS50Tha?
Agree with Mark; the TV x2.5 Powermate is a wonderful bit of kit for planetary imaging but has a very bad reputation for creating Newton's rings when used for Ha. Not sure what camera you are using? My PG Grasshopper is totally immune to NRs (the main reason I bought it) but my DMKs and ZWOs were pretty much un-usable with the Powermate.
My 'cheapo' Skywatcher can have its from element un-screwed - I can then screw it to the nose of my camera and get good results.
I would have thought that using a Barlow would reduce the limited in-focus problem?
My 'cheapo' Skywatcher can have its from element un-screwed - I can then screw it to the nose of my camera and get good results.
I would have thought that using a Barlow would reduce the limited in-focus problem?
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Mike Garbett
Selection of Solar and Deep Sky images on Flickr: https://www.flickr.com/photos/mikegarbett/
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Mike Garbett
Selection of Solar and Deep Sky images on Flickr: https://www.flickr.com/photos/mikegarbett/
Re: Barlow-ing the Lunt LS50Tha?
Thanks guys - Something to save me money is always good!
I might explore the Telecentric possibilities for other stuff...
Re. Cams, I am using a ZWO120MM. Unfortunately specifically
with the Lunt LS50THa "backend", mounting the SW Barlow
element before the diagonal just don't work...
It works fine in a conventionally focussed refractor. You can
get limited magnification by "floating" it between Lunt diag
and the cam. But, with focal length approx. (minus) 75mm
there isn't a solution! But then I stated thinking a bit...
Using 2x Barlows screwed directly onto eyepieces to give
1.5x is a useful dodge. No detailed calculation, but there
exist cheapish 5x Barlows of "standard" size! If they have
a facilty to unscrew the front element, maybe by analogy...
But I'll let you know (collectively) if this works!
I might explore the Telecentric possibilities for other stuff...
Re. Cams, I am using a ZWO120MM. Unfortunately specifically
with the Lunt LS50THa "backend", mounting the SW Barlow
element before the diagonal just don't work...
It works fine in a conventionally focussed refractor. You can
get limited magnification by "floating" it between Lunt diag
and the cam. But, with focal length approx. (minus) 75mm
there isn't a solution! But then I stated thinking a bit...
Using 2x Barlows screwed directly onto eyepieces to give
1.5x is a useful dodge. No detailed calculation, but there
exist cheapish 5x Barlows of "standard" size! If they have
a facilty to unscrew the front element, maybe by analogy...
But I'll let you know (collectively) if this works!