#1
|
|||
|
|||
eyepiece advice..
Ok, here's my question:
I have an 8 inch newt on a german eq mount. I have a nice televue panoptic for looking at deep sky stuff and a celestron xcel for planetary viewing. Of course i've gotten used to the superior optics of the televue so I want to get another for the planets. I've made a few calls to the local telescope shop and the guy tells me that I want a televue nagler type 6 at 3.5 or 5mm. They're both the same price and he wasn't real clear on the difference so I'm hoping the fine folks on this bb can pass on any advice in this area. So, which piece do you think is best? Or is there something more awesome than the vaunted Televue line? Money is no object so if there's some kind of ultra sophisticated eyepiece crafted by japanese hermits in a secrete underground laboratory ....I wanna know. Thanking you in advance for your expert advice, Brian |
#2
|
|||
|
|||
brian wrote:
Ok, here's my question: I have an 8 inch newt on a german eq mount. I have a nice televue panoptic for looking at deep sky stuff and a celestron xcel for planetary viewing. Of course i've gotten used to the superior optics of the televue so I want to get another for the planets. I've made a few calls to the local telescope shop and the guy tells me that I want a televue nagler type 6 at 3.5 or 5mm. They're both the same price and he wasn't real clear on the difference so I'm hoping the fine folks on this bb can pass on any advice in this area. So, which piece do you think is best? Or is there something more awesome than the vaunted Televue line? Money is no object so if there's some kind of ultra sophisticated eyepiece crafted by japanese hermits in a secrete underground laboratory ...I wanna know. How short an eyepiece you can use depends on the focal length of your primary. The usual rule of thumb says that you won't benefit from a magnification greater than 50X per inch of aperture, so your limit will be about 400X. If your mirror's focus is shorter than 400 * 3.5 mm = 1400 mm (meaning that the 'scope is faster than about f/7), the 3.5-mm EP should let you make the most of good seeing conditions, but if it's longer (slower) than that the 5-mm EP would be a better choice. -- Odysseus |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
FOV and f ratio | Matt St. Helens | Amateur Astronomy | 7 | October 3rd 04 02:59 AM |
Advice on Eyepiece + Barlow for FS-102 | maflu | Amateur Astronomy | 5 | May 14th 04 11:58 AM |
Eyepiece advice for Explorer 200 | Colin Johnson | UK Astronomy | 1 | May 2nd 04 09:13 AM |
Bands of Saturn. How many of them can be counted (really!) with 7" scope? | ValeryD | Amateur Astronomy | 294 | January 26th 04 08:18 PM |
*Review: Astrosystems 30mm WIDE SCAN III Eyepiece | David Knisely | Amateur Astronomy | 6 | August 8th 03 05:53 AM |