Daz Type-R Posted October 23, 2013 Share Posted October 23, 2013 So I have the 13mm TeleVue Ethos and I absolutely love it, it suits me perfectly with the exit pupil, the quality etc, it's just great. So I have started to think about my next purchases and I am at a bit of a dilemma, what do I get? I was thinking about another Ethos but this time the 8mm, I was also thinking about a 2 x Power Mate, doing the math I would get the following mm Ep's and magnifications..... 13mm, 8mm, 6.5mm and 4mm with 92x, 150x, 184x and 300x magnification (300 may be pushing the seeing limits I know). Realising that I have got nice low power with the 13mm, pretty much the same magnification with the 8 and 6.5mm and possibly too high a magnification with the 4mm, I wondered if a 2.5x Power Mate would be better. Just getting a 2.5x Power Mate for my 13mm would give me a 13mm EP and a 5.2mm EP, giving me magnifications of 92x and 230x, possibly too big a gap in the middle but a decent magnification at the top end. Using the 2.5x Power Mate would drop the 100 degree FOV down to 40 degrees which is still more than enough for planetary viewing. So I would use the 13mm for globular clusters, open clusters, nebula etc, then using the 2.5x Power Mate on the 13mm for planets and double stars etc? I'm very keen to stick to TeleVue now, so what do I get (if anything other than a Power Mate)? Link to comment Share on other sites More sharing options...
Perkil8r Posted October 23, 2013 Share Posted October 23, 2013 I would say the Atik 316L Link to comment Share on other sites More sharing options...
Daz Type-R Posted October 23, 2013 Author Share Posted October 23, 2013 I would say the Atik 316L Link to comment Share on other sites More sharing options...
Tweedledee Posted October 24, 2013 Share Posted October 24, 2013 Using the 2.5x Power Mate would drop the 100 degree FOV down to 40 degrees which is still more than enough for planetary viewing. Any size power mate with still preserve the full 100 degree apparent field of view that you love about the Ethos. It will just reduce the exit pupil and increase the magnification in proportion with its multiplying power whilst maintaining the eye relief. The true field of view will obviously reduce just like it would in a higher power Ethos. But maybe that is what you really meant to say anyway. The Ethos and power mate would make a great combination. The multiplying power just needs careful thought with regards to subsequent eyepiece purchases. I don't think you will stay content with just these two wonderful items and will eventually want more of these bank account busting Ep's. To look at this from a slightly different angle, have you thought about opening up your scope with the following eventual combination... Ethos 21 and 13 and 2.5x Power Mate providing almost equally proportioned increments 57x, 92x, 146x and 230x giving exit pupils from 3.6mm to 0.9mm and true fields from 1.75 degrees to 0.43 degrees. That is just my own preference, of course, to err towards the wider angle end of the scale Assuming you are determined to avoid the dark side, that is my 2 penneth Link to comment Share on other sites More sharing options...
+Ibbo Posted October 24, 2013 Share Posted October 24, 2013 Apart from Mikes brill idea My most used eyepiece in the dob is the 20mm Nag Link to comment Share on other sites More sharing options...
Sheila Posted October 24, 2013 Share Posted October 24, 2013 my suggestion would be eq mount, frac and ccd for you Link to comment Share on other sites More sharing options...
Daz Type-R Posted October 24, 2013 Author Share Posted October 24, 2013 my suggestion would be eq mount, frac and ccd for you Not helping....... Link to comment Share on other sites More sharing options...
Daz Type-R Posted October 24, 2013 Author Share Posted October 24, 2013 To look at this from a slightly different angle, have you thought about opening up your scope with the following eventual combination... Ethos 21 and 13 and 2.5x Power Mate providing almost equally proportioned increments 57x, 92x, 146x and 230x giving exit pupils from 3.6mm to 0.9mm and true fields from 1.75 degrees to 0.43 degrees. That is just my own preference, of course, to err towards the wider angle end of the scale This would be my perfect set up, the magnification increments are perfect but............................................... Just seen how much a 21mm Ethos costs...... £700. :o :o I think my next purchase will be a 2.5 x Power Mate and see if I can sell a kidney or two to fund the 21mm. Thanks Pete, never thought of looking towards a bigger ep than the 13, food for thought. Link to comment Share on other sites More sharing options...
Guest CodnorPaul Posted October 25, 2013 Share Posted October 25, 2013 There is one on ABS for £450 Darren Link to comment Share on other sites More sharing options...
Rock Doctor Posted October 25, 2013 Share Posted October 25, 2013 Darren, there's a set of Ethos and a 2x powermate on Astro BS Link to comment Share on other sites More sharing options...
Guest CodnorPaul Posted October 25, 2013 Share Posted October 25, 2013 Oooo - that sounds nice Darren... Link to comment Share on other sites More sharing options...
Guest Tweedledum Posted October 28, 2013 Share Posted October 28, 2013 Have you seen the ep review in s@n?? Link to comment Share on other sites More sharing options...
Daz Type-R Posted October 28, 2013 Author Share Posted October 28, 2013 Not seen it no, will take a look, but I have made up my mind. Next purchase will be a 2.5 x Powermate which means I will have 92x mag with the 13mm as standard, then adding the 2.5 x Powermate will give me a 5.2mm EP which equates to 230 x mag, perfect for the planets. I will then save and sell a few body parts to pay for the 21mm, might get it sometime around 2016! Link to comment Share on other sites More sharing options...
Guest Tweedledum Posted October 28, 2013 Share Posted October 28, 2013 That will be a very nice setup Darren. Link to comment Share on other sites More sharing options...
catman161 Posted October 28, 2013 Share Posted October 28, 2013 Exactly the next eyepiece purchase I am going to make-also a better focuser too but baby steps. Like you I may have to sell a limb etc! Link to comment Share on other sites More sharing options...
Daz Type-R Posted October 28, 2013 Author Share Posted October 28, 2013 Will the stock focuser be ok with the weight, I won't be attaching a camera so don't have to worry about that? Link to comment Share on other sites More sharing options...
Perkil8r Posted October 28, 2013 Share Posted October 28, 2013 Will the stock focuser be ok with the weight, I won't be attaching a camera so don't have to worry about that? I would say it will be getting close to the sensible limit. I've had the DSLR swinging off the back of 2 x barlows stacked together on the standard focuser though so you should get away with it. What can become an issue is being able to focus as the focuser tube might start slipping with that much weight. Link to comment Share on other sites More sharing options...
Doc Posted October 28, 2013 Share Posted October 28, 2013 IMO the stock focuser will struggle with a 2.5 Powermate and a 13E. I have tried a similar arrangement when I had my 16" dob and it struggled with revelation focuser I had on that. It's not only the weight, it's the length and the sag it produces. Link to comment Share on other sites More sharing options...
Daz Type-R Posted October 28, 2013 Author Share Posted October 28, 2013 IMO the stock focuser will struggle with a 2.5 Powermate and a 13E. I have tried a similar arrangement when I had my 16" dob and it struggled with revelation focuser I had on that. It's not only the weight, it's the length and the sag it produces. - B*@%*$£s. Now going off to research new focusers - any starters for 10 guys and gals? Link to comment Share on other sites More sharing options...
Perkil8r Posted October 28, 2013 Share Posted October 28, 2013 Moonlite, around £240 ish Link to comment Share on other sites More sharing options...
Daz Type-R Posted October 28, 2013 Author Share Posted October 28, 2013 And so the list of things to buy goes on, and on, and on, while the price goes up, and up, and up - why did I pick this hobby So it looks like one of these could be needed.... http://www.firstlightoptics.com/moonlite-focusers/moonlite-cr-dual-rate-tri-knob-crayford-focuser-for-newtonians.html with one of these..... http://www.firstlightoptics.com/moonlite-focusers/moonlite-installation-kit-for-newtonian-focusers.html Another £269 to fork out - Link to comment Share on other sites More sharing options...
Guest Tweedledum Posted October 28, 2013 Share Posted October 28, 2013 Camera would be cheaper ...but not as satisfying.... Link to comment Share on other sites More sharing options...
Daz Type-R Posted October 28, 2013 Author Share Posted October 28, 2013 Camera would be cheaper ...but not as satisfying.... Don't you start trying to convert me to the dark side (I must resist, I must resist.......) Link to comment Share on other sites More sharing options...
Perkil8r Posted October 28, 2013 Share Posted October 28, 2013 Resistance is futile Link to comment Share on other sites More sharing options...
Guest Kheldar Posted October 28, 2013 Share Posted October 28, 2013 Moonlite, around £240 ish This Link to comment Share on other sites More sharing options...
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