Evostar 120ED Pro vs AA RC 8"xf8

[obscura]

I am narrowing down to two OTAs to supplement my WO80.

First is the SW120Evostar Pro 120/f7.5 - plug and play

Second is the Altair Astro RC 8"/f8 - collimation/maintenance

Obstruction by secondary makes it similar to ED120??????

Thoughts and views appreciated on these two

[swag72]

I know that I have had the odd 'problem' with my ED120, all well documented on here, but if I change scopes it will certainly be for another refractor and something that I can get near to the 120ED in focal length. People say that the SW 120ED punches above it's weight and is a good scope for the money. Contemplating getting another scope and looking around for a similar sixe at a similar price and I have to agree - For what it is, it's extremely competatively priced. In fact, I really couldn't find much to touch it in that price bracket.

I have not tried anything other than refractors and for me, I like the idea of less tinkering than with the others. Far more plug and play.

I have looked () through the 120ED a couple of times and I have been impressed with the views although I am no expert at all. For imaging, it's a good scope and even though I do have the odd issue with it, I really would not knock it.

The only thing I would say is that if you are imaging, it's a good idea to think about a focuser upgrade, or be prepared to have a tinker with the stock focuser to improve it - I found it pretty woeful. The Moonlite's great though!

So, no comparison I'm afraid, but just some ramblings on the 120ED.

Hope that helps.

[ollypenrice]

Getting those RCs perfectly collimated is difficult, it seems. On the other hand does the SW give you a big enough increase in FL? Personally I would cling to refracting until absolutely forced, kicking and screaming in protest, to swap to a reflecting system. In the end, sadly, the need for more FL at a reasonable F ratio makes reflecting unavoidable. Are you happy with about 900mm? If so I'd continue to refract!

Olly

[obscura]

Sara, I am not aware of any serious probs with 120ED Evostar other than maybe its focusser. Are there other points I should look for?

I had some nagging thoughts on fl - is 900 long enough for those faint small fuzzies? It comes down to affordability I suppose. I know you are right wrt to frac vs flec and i am biasedtowards fracs - but oh for another 100 or 2mm on a frac.

[swag72]

The problems I think have been with the focuser and the connections from the focuser to the OTA. It is still under test before I finally decide where to go with it.

One thing I have learnt is that if you are imaging and you want acceptable stars, you really do need the flattener. The dedicated flattener is a 0.85 reducer so takes you from 900mm to 765mm and f6.3. So you've lost evern more mm's. I think that TS have a flattener that isn't a reducer that will work, I think Harry Page has one, there's some details on his site.

Sometimes we need to make compromises as well as be a little more realistic than optimistic I fear.

[obscura]

Thanks Sara. Once I get this OTA, which looks like the frac, I'll check it out and pick one of these up.

[jam1e1]

have a newer model focuser on my SW120ED - by that i mean the DS focuser does feel slightly better in that you feel sligt graduated 'bumps' as adjust the finer focuser (black adjusting knob as oppsed to gold one). May be just aesthetical change but does feel slightly different to old.

You can improve the standard focuser slightly by tighening the DS focuser and smoothing out the drawtube with an appropriate metal file (oilstone file think they are called) did make mine grip more.

[obscura]

I could be OK then but wil take note of your findings.

(I have two unwanted white light street lights outside the house!)

[Coco]

The problems I think have been with the focuser and the connections from the focuser to the OTA. It is still under test before I finally decide where to go with it.

One thing I have learnt is that if you are imaging and you want acceptable stars, you really do need the flattener. The dedicated flattener is a 0.85 reducer so takes you from 900mm to 765mm and f6.3. So you've lost evern more mm's. I think that TS have a flattener that isn't a reducer that will work, I think Harry Page has one, there's some details on his site.

Sometimes we need to make compromises as well as be a little more realistic than optimistic I fear.

Sara 120ED?I'm surprised you need a flattener with the 285 chipset, I didn't with my old Meade 127 APO? it might be your scope as I am sure you wouldnt need one?

[johnrt]

Let me play devils advocate for a moment.

I have the Altair 6"RC, and coming from owning refractors exclusively before I bought it, I found the learning curve on collimation and getting it generally set up right was quite tough. I had to ditch my side by side bar, add a counter weight extension & I still plan to upgrade the saddle on my HEQ5.

BUT!

Once everything is as it should be, the scope begins to sing. It has a robust focuser and hold it's collimation well once you've got it right. I run mine with a WO ff/fr II which reduces the focal length to 1096mm at f7.2 - just perfect for galaxies and small objects like planetary nebula with my Atik 314l+

[Nadeem Shah]

Sara 120ED?I'm surprised you need a flattener with the 285 chipset, I didn't with my old Meade 127 APO? it might be your scope as I am sure you wouldnt need one?

echoed... I certainly did not need one even when using the 120ED with a Atik 383L+.