143 replies to this topic

[Blair]

I have the Stellarvue 80/9D (2002 version which does not have the retracting dew shield). It is a very good scope and is good up to about 200X on double stars and the Moon but I've not been able to go that high on Jupiter, probably because of seeing. I did not mention it because it seemed you wanted a larger scope. In general, when dealing with well made scopes, the more aperature the more detail you can see on Jupiter. Plus you can buy a 102HD with mount for the price of just the Stellarvue OTA here in the states. My Stellarvue 80/9D way out performs my 90mm f/11.4; shows less color. I only suggested a Mak because of your limited space requirement. Heck, if I had a permanent place to put a mount I would have a 6 inch refractor. Maybe, someday.

[Norvin]

PhilD: Have you thought about perhaps using a Dobsonian in about a 6" - 8"? I have an 8" Hardin Optical Dobsonian DSH-8 which I extremely like and I would think I could use it on a small balcony. In fact, it might be a better choice. You wouldn't have to put up with the room a decent refractor mount would need after its legs are extended. On top of that, they are cheaper in money but not in quality.

I am not advertising for this seller, but here is a new Dobsonian in your neck of the woods...

http://cgi.ebay.com/...item=3251737658

Norvin
Post #118

[Ron B[ee]]

I'm sorry for the poor image quality

You should have taken the picture with a refractor .

Ron B[ee]

[Ron B[ee]]

I have NEVER seen anyone make such a suggestion in a refractors group before, though. You guys are endangering your memberships in the TV Yahoo group...

Though the 4-inch Tall Evangelist is enamoured with 4-inch refractors, he is ever vigilant, practical and realistic in the needs of the many .

Ron B[ee]

[Blair]

I guess there are 2 questions.

1. What do you look at mostly?

2. How much do you want to spend?

My Stellarvue 80/9D (80mm objective with 750mm focal length) is an excellent performer. The new Orion 80 ED seems to be an excellent scope if you can get one. The 127mm Mak with its long focal length will allow you to get to higher powers faster and with longer focal length eyepieces than the previous mentioned scopes. Better eye relief and all that. You probably wouldn't need to use a barlow as much to get to the power you want with the 127mm Mak versus the other scopes. If you can get a Stellarvue from Vic one thing is for sure it will be collimated properly. It seems everyone that has received Orion's 80 ED has had to, at least, tweek the collimation by messing with the focuser as the scope does not have an adjustable cell. Good luck on your decision; its not an easy one.

[Norvin]

Light pollution shouldn't be a problem...

Light Pollution And Dobsonians

Magnification shouldn't be tricky and yes it is very easy to track not only planets, but stars, nebulae, etc. Just be sure not to overtighten the main bolt on the mount itself.

Norvin
Post #120

[Norvin]

Here are some more Dobsonians in the U.K.

http://www.sherwoods...r_dobsonian.htm
http://www.telescope...o.uk/skydob.htm

I still like that one on eBay, in fact, if you look at the bigger picture for it, I think it says Guan Sheng on the tube by the focuser. It's gotta be good if it is. That is the same company Hardin Optical uses and Orion use to use until they sued Orion.

http://cgi.ebay.com/...item=3251737658

Norvin
Post #121

[Norvin]

I think a Dobsonian would work fine. The mounting is low, but the tube is longer. What is that? A 3' rail? You could make a small board and put small legs on the bottom of it to get it up higher if needed.

Norvin
Post #122

[Norvin]

About 20 - 30 minutes for a Dobsonian.

Norvin
Post #124

[Ron B[ee]]

Norvin

Interesting idea about the Dob. I've never used one - aren't they a bit tricky at high magnifications or is it quite easy to track a planet with a small nudge. Also would all that extra aperture be wasted given my appalling seeing conditions? I live in the South of England and there are no really dark skies anywhere near so it would be used 95% of the time for planetary and lunar observation.

Phil

I have an 8" PDHQ Discovery f/6 Dob and it's no small scope. One caution: because the Dob is mounted low, you should check to see how high of a railings (if any or solid wall) on your balcony. Otherwise, you may find you can use the Dob on at the high altitude part of the sky.

Personally, I find with a wide field eyepiece such as Radian or Nagler, it isn't a problem nudging at 200x. 300x starts to be annoying and painful and 400x is just torture for me , which is why I probably want an EQ platform someday. Was your C102-HD on EQ mount with motor drive? And then, there's cooldown time, collimation issue and diffraction spikes with Dob. My Dob (without fan) takes a lot longer to cooldown (up to 2 hours) whereas my TV-102 can be used almost immediately or after 10-15 minutes. If you go with tube Dobs, I've found mine hold collimation very well and I try to be careful when I move mine.

I've been doing comparison on many nights since I have got mediocre seeing between my 4-inch TV-102 APO refractor and the 8-incher. Here's my observation (not a decisive conclusion, not yet anyway). I even tried aperture mask using my son's T-shirt . The object was Mars and the Moon. The Martian rim was noticeably more vibrating; at times I can see several "Mars" with the 8-incher With my 4-incher, the view seemed "calmer", but upon closer examination, I think I know why. Because the 4-incher gathered less light, it was hard to see some of the "dimmer" fast vibrating rims. So it gave an illusion of a "calmer" view, but then what you can't see ... . So I put the T-shirt on and covered half of the 8-incher aperture and sure enough the view was "calmer" as well! However, on some other nights, the aperture mask was no help and the view was approx. & equally bad through both scopes . On the Moon, the view seems to shimmer more rapidly with the 8-incher. I think this is because the 8-inch can resolve even finer turbulence. On the otherhand, just the other night, the Moon was so bad like looking under water that both scopes gave very unpleasant view! But on good seeing nights, the 8-incher will show you more than the 4-incher (though I still find myself using the 4-incher much more for some inexplicable reasons ). So take this with a grain of salt if you like, Phil.

For an excellent article on seeing, please have a look at this.
http://www.cloudynig...tos2/seeing.htm

Ron B[ee]

[Ron B[ee]]

If I maybe so bold as to caution you Phil about aperture since this will be your only scope; IMHO the 80mm aperture is too small for a good view of the planets. Heck the 4-incher is bare minimum as it goes! See what the ALPO recommends.
http://www.labbey.com/ALPO/Index.html

Ron B[ee]

[Victor Kennedy]

Hi Phil:

The price of astro equipment shipped from the U.S. to Europe is scandalous. I don't know about UK dealers, but I have dealt with APM in Germany, and have heard they are reliable from others. Check out their website at

http://www.apm-teles...lisch/index.htm

They sell a nice-looking 130 mm Mak-Cass under their own brand for 340 Euros, as well as being a dealer for Vixen, Meade, Televue, and others.

I don't think you will have to pay any extra taxes or duties shipped within the EU (I didn't), but you could double-check.

[Norvin]

I would still recommend the Dobsonian...

- More apature = more stars, more planets, etc.
- Less money.
- By saving money, you can buy more EPs, filters, etc.
- No false colors / no apparations.
- Use a board with legs on the bottom of it if you need to raise the telescope to see over the railing.

Norvin
Post #124

[matt]

Phil (and others), in the UK you have a very nice astro-classifieds website, called www.ukastroads.co.uk
It's run by a saint samed Chris who basically sets up the ads by hand from people's submissions, without any ads whatsoever. I shop there often!

I won't give my opinion on refractors now as I have one for sale on ukastroads, there would be a conflict of interest!