powermate 2.5x and eyepiece selection advice

[markyb555]

Hi folks,

After abit of advice, ive recently bought s few eyepieces from AB&S (6mm Radian and 19mm Panoptic) and obviously keep my eye out for other little bits coming up. Ive been looking at adding a powermate 2.5x to that little list to give it some flexibility. I'm still very much an novice at this sorta thing so some advice as to whether is a waste of money or if its usable?

My scope is a Skywatcher 200p.

At the moment I'm observing planets but I would like to delve deeper into DSO using wider EPs if I could. It would be appriecated if anyone could advise me further on other EPs

Thanks

[russ.will]

Well, you're riding along the right lines picking up second hand Radian & Panoptics anyway.

At 6mm (200x, 1mm exit pupil), you're not going to go much higher in magnification before seeing, on all but the best nights, becomes the limiting factor anyway. I'd say an 8mm (150x 1.33mm ep) is a very hand EP to have as it will still give decent views of planets, but will work on practically every night and will be good for globulars/smaller galaxies.

After that and more to give framing options for larger DSOs, I'd probably target something about 12mm (100x, 2mm EP) as yopu can practically spend a whole night at that magnification.

For the other side of your 19mm, something in the 28-30mm range as a wide field/finder EP.

As far as the Powermate goes, well, they're always handy to have around and you'll probably never sell it, but the problem with the 2.5x magnification is that it's a little more than is useful for visual applications in my view. The 19mm Panoptic will become 7.6mm (so will fill the role of 8mm EP suggested above) but that's about all it will do. The 28-30mm suggested above will be 2" if you want to maintain that SWA apparent field and there isn't really a need for an EP between 19 & 28mm, just to make use of the Powermate.

It may be worth having a look at the Meade Telextender/ES Focal Extender/Bresser SA Barlow. They, like the Powermate, are telecentric amplifiers (The Bresser isn't a Barlow, despite it's name) and are virtually identical in performance. However, they can all be had in 2x, which I feel is a bit more useful.

Russell

[John]

It would be useable with the 19mm Panoptic for an effective 7.5mm focal length eyepiece. Too much power (500x !) with the 6mm Radian though.

Your 19mm Panoptic will be a really good deep sky eyepiece. If you need lower / wider you may need to think about the 2" eyepiece format.

As Russell says, 12mm / 13mm is also a really useful eyepiece focal length.

[markyb555]

Thanks for your thoughts. I has been looking at the vixen NVL range but the second hand Televues was just as much so thought I'd give them a go considering the amount of excellent reviews they had. The panoptic sounds like the right sort of range I needed but that good, I don't really require much else.

By the sounds of it, the powermate isnt going to be of as much use as I thought either, although it would be handy when I bob the DSLR camera on for taking lunar photos etc. If I could find a 2x variant that would widen it up abit more or research the Bresser/Meade variant?

I'll keep my eye out for a 12-13mm (depends what pops up) and have a think on the powermate.

Thanks again for your input and thoughts.