Quote:

---

To round out my lineup (see sig line, below), I have been thinking seriously about picking up a 4" Apo. They are readily available, portable, relatively light, cool down quickly, and have virtually no collimation issues. prices are within reach of most, new and used.
Lotsa choices!
If you expand the range of candidates to include the 90 to 110mm range, then the field of choices really explodes.
But which one?
I am a visual observer, and have both driven and undriven mounts.

So, a poll: Which is the best one for the job?
What is it about your choice that makes it stand out?

Thanks!

---

Post Extras:

Quote:

---

I think we need to know your price point to make a real recommendation. Lots of difference between the price of a Takahashi on the high end and one of the new Lunts on the low......

---

Need not be a "budget" Apo, and I don't do astrophotography.

I am not averse to buying in the aftermarket, either!

Edited by Levine (12/03/12 03:40 PM)

Post Extras:

Quote:

---

Based on that, although hard to find, I agree with waso29, a used Tak FS102NSV would be what I would get. You get world class Tak fluorite quick cooling doublet optics in a compact package that accepts a binoviewer without optical correctors.

---

+1

Post Extras:

Quote:

---

Hi John,

Hows that C-14 working?

Don't forget the Televue NP101. The wide field views are fantastic.

Richard

---

Post Extras:

Quote:

---

Don't forget the Televue NP101. The wide field views are fantastic.

---

After a couple of years of really enjoying my AstroTech 102ED, I had so much fun and it was getting so much use, I decided it was time to treat myself to a topnotch apo.

I really didn't do a huge amount of research but I did know that Tom Trusock had given good marks to the NP-101 and it seemed like one the obvious choices though I did not know at the time what sets it apart from the others. I watched an NP-101 go buy on Astromart for about $2000 and later I regretted having let it go. The next time one was available, I bought it.

The scopes discussed so far are 4 inch class scopes and at high powers they all are quite good, the NP-101 has what is to my eye perfect color correction even out of focus, the CA is not there and it does a great job on double stars and the planets. But a 4 inch scope can only do what a 4 inch can do when viewing the planets, splitting double stars, a decent quality reflector of sufficiently larger aperture is a more effective tool for viewing the planets, splitting doubles... 4 inches is 4 inches.

So... what is it that a 4 inch scope does better than an 8 or 10 inch Newtonian, Mak or SCT? It's portable and compact and Bingo... low power, wide fields...

This is what sets the NP-101 apart from the others, when the skies are dark and clear and the Milky Way is shining bright, it's short focal length combined with it's flat field takes it to the next level. A 31mm Nagler in an NP-101, there is no field curvature, no astigmatism, it's 4.5 degree field of view is about as close to heaven as I'll ever get.

So... my take: There are a lot of good 4 inchers around. The AT-106 and the very similar scopes from StellarVue and others look attractive. But if you want the scope excels visually at doing what 4 inch refractors excel at, the NP-101 is it.

Jon

Post Extras: