Wojo's Lone Pine Observatory
Starmaster 14.5 f4.5 and a Meade 2080 Astro Systems Nexus W/iPad DSC 9mm,13mm,17mm Naglers 19mm,24mm,27mm,35mm Panoptics, Paracorr and 2x Powermate
Quote:Hi all,Going to upgrade a 'free' Barlow that came with my scope.I'm looking at the TV line and I don't understand the difference between their Barlow and Powermate. 2x, 3x, 4x, etc.I use an 8 inch SCT for visual and astrophotography.If not a TV offering, can anyone recommend a Barlow that would be an upgrade over my standard Parks Barlow?Thanks in advance!
David W. Knisely . . . . . . "If you aren't having fun in this hobby, you aren't doing it right." Hyde Memorial Observatory http://www.hydeobservatory.info Prairie Astronomy Club http://www.prairieastronomyclub.org
Happy owner of-- A Mag 1, 12.5 inch Porta Ball A Dual Axis Equatorial Platform A PST Double Stack
Quote:It seems like in most cases, the Powermate is the way to go????
Quote:A Powermate is a corrected barlow no aberrations. You can unscrew the 2" eyepiece housing and screw on a T-ring adapter for attachment of CCD or camera
Quote:A Powermate is a corrected barlow no aberrations.
You can unscrew the 2" eyepiece housing and screw on a T-ring adapter for attachment of CCD or camera
I'd rather be driving my .
Quote:Mr. David Knisely,When you say that the PowerMate only needs a small amount of outward focuser travel to work, how much are we talking about? For example, my 8mm Ethos, my farthest outward focusing lens, leaves me with approximately 1/4" of remaining outward focus. Is that enough to use it on the 8mm Ethos?
Home-built Newt: 10" f/4.5 Royce conical primary, Skywatcher NEQ6 (Astrotroniks tuned) iEQ45, Duo-T, 8" f/4 Skywatcher Quattro CF 120 ED f/7.5 Skywatcher Black Diamond 80ED Stellarvue
Quote:I know I'll be using a PowerMate 2X when conditions allow. True, I may not have needed to add the riser, at least according to ThreeD, but now I will have the full focuser travel available and I know the 8mm Ethos, or even a 6mm future Ethos, will come to focus no matter what while using the PowerMate.
Quote:Thank you for a very interesting discussion. Since some time has elapsed since the last post, I hope folks don't mind if I resurrect it and ask some related questions. I recently bought a smaller refractor, and, unsurprisingly, I find that the eyepieces I had for my 8 inch SCT do not give high enough magnification for planets. I have been thinking of upgrading my Celestron Barlow that came bundled with my SCT. Would a TeleVue 2x Barlow or PowerMate (or other product) give noticeably improved performance?This is for a 90mm F7 Refractor. The highest magnification ocular that I have is 8.8ES82. (I also have 11mm and 14mm that could be barlowed.)But I am not committed to the Barlow route. I guess mine is actually more of a general question regarding eyepiece strategy for this unfamiliar focal length. Also I'm curious as to the purpose of the 2 inch Barlow or PowerMate discussed above. Intuitively, it seems like this type of amplifier would be used more for achieving high magnifications. But I'm sure I'm missing something. Any remediation of my benightedness would be greatly appreciated. Maybe people use them for the 9mm Ethos?Cheers,David
Quote:Thank you, David. As good or slightly better... It sounds like any improvement would be minor. I think I understand what you are saying about 2" barlows: 2" finder EPs to locate a target, then Barlow for a better look, e.g.Cheers,David
17.5" Dob "Beta Version"
NP 127 on a CG-5 and CGEM DX
25x100 and assorted other binos
Naglers, Ethos and various others.
Quote:Imaging the planets is something I've been wanting to get into. I've got a 1000d in prime focus behind a CPC11 and I find the magnification is not significant enough for when it comes to planets. Im not to savy with magnigication details so ill say this. At my current focal length I can just barely fit the whole moon into my camera's FoV. Not enough.. so with backyard EoS I can record via the live view. The power mate seems to be the way to go. But which one? 2x or 4x. My goal one day is to be able to achieve detail on the Jovian moons. So would a 2x do the job? I realize a 4x would be at the mercy of the atmosphere, but surprisingly this small, light polluted town of mine seems to be blessed with some stable air above it.
Orion xx14g Dob CPC 1100 w/Skywatcher 80ED piggybacked Coronado PST TMB 92L refractor AT Voyager mount Nexstar 6/8 mount Denk Big Easy binoviewers Oodles of eyepieces and other optical gadgets Past scopes Meade 8" reflector and 8" SCT
Quote:From what I see, planetary imagers are using modified webcam technology and image processing techniques like stacking to produce the fantastic photos of Jupiter and Saturn. One does not need a large frame size because one is limited by the resolution of the scope, only so many pixels are needed. Jupiter is only about 40 arc-seconds in diameter if you are oversampling and using 0.25 arc-seconds/pixel, this is only 160 pixels x 160x pixels. They key is transferring at 30 or 60 frames per second uncompressed video, getting a lot of data and then processing it to increase the signal to noise ratio.Jon