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Old 22-07-2018, 11:26 AM
Startrek (Martin)
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Televue Powermates

I have the full series of TV powermates with T ring adapters which I use for planetary and lunar observation and imaging.

I canít find any info on coupling 2 powermates to use with my DSLR for higher mag detail lunar imaging.

I have used my 5x powermate successfully for lunar imaging but would like to image with more close up detail ( dependant upon atmospheric conditions and phasing )

Has anyone used 2 Barlow or 2 powermates for lunar or planetary imaging ?
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Old 22-07-2018, 01:52 PM
Zuts
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Hi,

I tried it once with a 3 by Televue barlow and a 2 by Celestron barlow. This gave me a theoretical focal length of F60 or nearly 18 metres on my CPC 11 F10 SCT as the magnifications multiply.

This wasn't a great success as at that magnification there is never good enough seeing to realise the full potential of F60. So you would get the same results just by using one barlow and digitally zooming, a bigger image but no more detail.

Also since the two barlows were joined together the imaging train was rather long and with the camera connected was probably no longer exactly square to the optical axis, as there was some flex.

I may be wrong but I think you can increase the magnification just by adding an extension to the bottom of the barlow, though I am not sure what the magnification formula is. This may be a 'lighter' way to go.

So yes it is possible but depending on your equipment the results may not be great.

Still you can give it a go and see what happens

Cheers
Paul
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Old 22-07-2018, 02:23 PM
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Merlin66 (Ken)
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Yes, a similar question was asked a few years ago.
I set up the x2 and x2.5 PM's to verify they worked OK.
No issues, no drama.
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Old 22-07-2018, 06:11 PM
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Stonius (Markus)
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The 5 x powermate will give you up to 8X if you put a 100mm spacer in the top, according to the TV website http://www.televue.com/engine/TV3b_p...id=53&Tab=_app

Markus
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Old 27-07-2018, 09:58 PM
TareqPhoto (Tareq)
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I ordered 2x to be my first ever Powermate, but later once i sell my extra Polemaster then i will order 5x Powermate although there are some trying me to avoid this 5x.


Now my only curiosity is, if i have let's say 2x and 5x, is it necessary to have 2.5x and 4x too?
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Old 27-07-2018, 10:43 PM
Startrek (Martin)
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I use the complete set of powermates as I visually observe and also image with 2 different telescopes

It depends on what level of astronomy you expect to achieve in the future

Powermates are high level accessories and are a long term investment in this hobby
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Old 28-07-2018, 09:55 AM
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Merlin66 (Ken)
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The x2.5 and x5 Powermates are 1.25" designs whereas the x2 and x4 are 2" designs.
Over the years I've had and used all the Powermates. Unless you're imaging with an f5 scope, the x5 is of little use.
I also found the x4 "handy" but was used much less than the x2 or x2.5 version.
Just my 2c
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Old 28-07-2018, 03:22 PM
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Glaring omission in their line is a 3x powermate in 2", IMO.

- Markus
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Old 28-07-2018, 08:59 PM
TareqPhoto (Tareq)
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Away from 1.25" or 2" size, i just curios why someone will collect all the lines of Powermate? or let's say if someone has 2.5x why he needs 2x or if he has 4x why he needs 5x.


Now i have a Mak 180mm f15, so i think 2x is the best suit from Powermate, not sure about 2.5x so that i ordered 2x, and i also have Newtonian 8" f5 so that i want to have 5x, and i am planning to buy another Newtonian or maybe a dob that is about f4-4.8 so 5x will be just fine, and i am skipping 4x until next year or if i get a budget within Oct-Dec without another expense that time.


How do you rate this Powermate anyway, is it high quality? let me give an example, if you have a scope for example that give you native 4000mm without any Barlow and another scope that gives you 2000mm and you use a 2x Powermate, will be there much difference in quality? assuming both will be around f10-f12.
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Old 31-07-2018, 11:47 AM
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sil (Steve)
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Quote:
Originally Posted by TareqPhoto View Post
Away from 1.25" or 2" size, i just curios why someone will collect all the lines of Powermate? or let's say if someone has 2.5x why he needs 2x or if he has 4x why he needs 5x.

two scopes would be a good reason, one imaging away and another for visual or imaging something else. Probably didnt start out to get them all maybe picked up some good bundle deals second hand etc just to get one of them for second scope and ended up with all in the end.

Or just a collector

As for need? hm, the eye can compensate and sharpen up what its seeing pretty well and every bit of magnification amplifies optical defects. Plus with barlows and powermates youre often at or beyond the magnification limits of the scope. Along with changing seeing conditions I can easily see how a 4x and a 5x can give noticably different results, maybe a 5x is ok for visual but imaging is just too poor whereas a 4x loses little in magnification but may gain much in clarity and sharpness when imaging.
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