120 mm or 102 mm f/5 refractor for rich field visual?

[Camelopardalis (Dunk)]

Sounds good Barry, now you just need a nice 2" eyepiece to widen the view even more

Btw I can't see it on their site any more

[Amaranthus (Barry)]

The field flattener? It's still there: http://www.bintel.com.au/Astrophotog...oductview.aspx

Re: 2" eyepiece -- given the washed out look of my Pan 24 under urban skies, I'll wait until my move before I even consider this.

[Camelopardalis (Dunk)]

No, the 120 f/5 scope I must be blind

Yeah I get what you're saying about urban skies, where I used to live about 60-70x was about as low as I could stomach the orange glow but on trips out to darker skies here it's

Btw, the 2" barrel isn't just to facilitate longer focal lengths, but also to enable wider apparent field of view of mid focal lengths..even some shorter ones have 2" barrels by default (ES100 for example) for stability. I just love the immersive wide views from 82 and 100 degree designs in my scopes, but appreciate it's a question of taste. My favourite to date is the 17mm Ethos which is just spectacular in all of my scopes. But I'm just as you can tell

[Amaranthus (Barry)]

The 120 f/5 scope is here: http://www.bintel.com.au/Telescopes/...oductview.aspx

...and various other places around the net.

I'm getting 82 degrees in my 16 mm and down, and 68 at 24 mm, so it's fine for now. Yes, I will go down the 2" route, but it's not a priority. I seem to have it the sweet spot, IMHO, in terms of useful FOV where I live right now.

[cometcatcher (Kevin)]

Great review Barry and very glad you like the scope for visual use.

[Crazydog (Lea)]

That was a good review and pushed me over the edge....I ordered a sw120 today. I won't have the nice eyepieces, which I know will make a difference, but I'll have the dark skies, and I think I'll be impressed with anything compared to my old Tasco 60mm!

[Amaranthus (Barry)]

I think that you won't regret that extra aperture, Lea. And you can always start a premium EP collection in the future - no rush!

[raymo]

I find the tripod is stable, and the slow motions work o.k. but one huge
drawback is that even with my little SW 80 on it, if I add my 1100D I have to hang a kilo of weight from the lens hood to stop the targetfrom moving. If I tighten the large nut enough to stop this happening,
I can't move the platform by hand when the slow mo adjustment runs
out of thread. Being as I almost exclusively do imaging, I now never use the tripod.
raymo

[clive milne]

Originally Posted by MattT

My computer won't let me cut and paste it but google... Richest Field Telescopes by Mel Bartels

Lots of info there.

It's a shame that your comment didn't get any traction Matt, it was probably the best piece of advice given in this thread. iirc) the article Mel wrote on this subject was derived from a fairly lengthy discussion amongst members on the old ATM list. I think it was around 1999 or 2000 and should still be in the archives if that helps.

As you intimated earlier, there are legitimate reasons why a 6" f5 Newtonian is close to the optimum rich field instrument. There is one configuration that is demonstrably better though. That being a 6"f5 Newtonian binocular with coma correctors.

best,
c

[Amaranthus (Barry)]

I took notice at the time Clive - I agree it was an excellent summary!

[Camelopardalis (Dunk)]

Originally Posted by clive milne

That being a 6"f5 Newtonian binocular with coma correctors.

That sounds interesting...anyone got/making one?

[MattT]

Read your way through this...http://www.bbastrodesigns.com/tm.html

Recently I bought a 102 f5 thanks Zane and put an ES 30mm 82º eyepiece on it and A revelation compared to any other eyepiece I tried in my first 4" f5. A tiny bit of FC and a TFOV of 5º... very nice. Perhaps a Nagler 31mm might be better, but my wallet says no way!
Matt

[clive milne]

Originally Posted by Camelopardalis

That sounds interesting...anyone got/making one?

Mark Sutching had an 8" binocular (I don't think it is still around) I had look through it probably 20 years ago. I remember two things clearly, it showed objects as well as the 12" nearby, and the aesthetic appeal of the views were second to no other telescope on the field irrespective of aperture or configuration (including a 7"AP). I have been sold on the binocular Newtonian principal ever since. I built one for myself (all be it with larger aperture) Dave Moorehouse saw some pictures of my bino's and built a pair of 16's, 3RF have a pair of 12's, and there is at least another pair of 14's over on the east coast.

In my experience, if you are a purist and would like to see the universe rendered in the very best way possible, binocular Newtonians are a very cost effective way to do it.