SkyWatcher Evostar 90/900 or Celestron Astromaster 90/1000

[Mike_S]

Hi,

Sorry ignore my previous post as I have changed my mind. Which of these would you recommend for a first scope. I understand that it seems to be a trade off between field of view and CA reduction. F10 vs F11.11. I can’t decide what. Just for planetary and lunar observing to begin with.

here they are.

https://www.firstlightoptics.com/celestron-astromaster-series/astromaster-90az-telescope.html

 

https://www.firstlightoptics.com/evostar/skywatcher-evostar-90-az3.html

 

[John]

The Skywatcher has a better mount (just about !) and is less expensive.

Nothing much between an F/10 and an F/11.1 in chinese refractors.

If I had £150 to spend on a 1st scope I think I'd be looking for a 150 F/8 dobsonian on the used market.

[SIDO]

I use a 90mm F11 Achro for planets on a eq5 Exos2 with a 58mm aperture mask and like it a lot. Shows less detail than my 200mm dobsonian but nice contrasting views indeed. I fully flocked the tube as the baffles are designed for a 90mm aperture  not a 58mm one. Good 90mm F11's are hard to come by these days, I would go F11 before f10 as you would get above minimum colour correction for a 90mm Achromatic Refractor. My 58mm aperture mask gets me a 17.2 FR and a Conrady scale of 7.8 making for some very nice veiws using my 90mm for planets.

Edited August 4, 2018 by SIDO
misspelling

[SIDO]

[nightfisher]

of the 2 scopes i would choose the skywatcher 90

[Chris]

The skywatcher has the slow motion controls which are a plus. I've owned that model and found it performed well on planets once the terrible prism diagonal was replaced. 

I believe the Equatorial mounted version has a better mirror diagonal. With an equatorial mount you point the polar axis at Polaris the pole star ( easy to find) then swing the scope around to the object you want to observe, then you can simple tract the object by slowly turning one of the slow motion controls rather than juggling two. If you add a right accension motor it will track by it's self.

Either get the skywatcher 90AZ plus a better diagonal, or the 90EQ on it's own, or consider adding the motor for a easier life at the eyepiece and easier sharing experience.

[Mike_S]

Thanks, I'm not interested in an EQ mount to start with. I've been calculating field of view and magnification with the lenses supplied and with some optional ones. There is also the Evostar 90 AZ pronto that appears to be a much better mount. I can always put in a 32mm eyepiece for a wider field of view. Also looking at spending more on something that comes with a dual focuser for 2 inch eyepieces as well but probably won't on this occasion due to the cost. F11 does sound good though. Are both scopes the same build quality pretty much, by synta?

[SIDO]

Build quality on these lower priced achromatic mid focus refractors are similar and you are correct in wanting a 2" 2 speed focuser in my 90 f11 I get a 2 1/2° field or about 5 moons wide with a 2" 40mm eyepiece. The Celestron 90az has good optical reviews and bad mount reviews, but I can tell the difference between f10 and f11 at the eyepiece and the amount of extra CA that brings is quite noticable so that being the reason I suggested the f11. One can stiffen the mount but the optics are set in glass and more difficult to correct.  Limited funds always makes for harder choices the used market can sometimes come thrue with a bargin or at least a better scope in hand. 

[Mike_S]

Nebula, which 90 F11 do you have that takes 2 inch eye pieces?

Edited August 4, 2018 by MSammon

[SIDO]

My profile picture is that scope it's a 1990 Meade 390 90mm F11.11 x 1000mmfl, I tossed the original mount, focuser, rings and dovetail in the trash and replaced them so the only original components are the tube, lens cell and dew shield. Last year I bought three more of these used Meade 90mm scopes for the lens cells and sent the four lens cells in for optical testing, pairing, alignment and respacing now I have an extremely mint almost optically perfect 90mm F11. About $1100 US invested so far and very very happy with the results, awesome achro for sure. The base componants are indeed used though ?

Edited August 4, 2018 by SIDO
I messed it again ;-)

[Mike_S]

Thanks, they don't appear to sell the Meade 90/1000 anymore. I've just read that AZ mounts are meant for terrestrial so maybe I should get used to an EQ. Can you tell me if this has a star diagonal? As the 90/900 Evostar EQ does and is cheaper than the AZ. 
https://www.firstlightoptics.com/beginner-telescopes/celestron-astromaster-90eq-telescope.html
It's only for 1.25" eyepieces though, do you think that should be okay say if I purchase a 32mm?

Edited August 4, 2018 by MSammon

[SIDO]

I would go EQ as it allows for single handed long period observations wich is a requirement for planetary observations, one can always add a drive motor even on a single axis this will get you hands free. 

[SIDO]

The Meade 390/395 scopes still do come up for sale used, the four that I bought where all useable scopes better optically than today's cheaper achros. The cheapest of the four I bought was $40 and the most expensive $125, the 390/395 scopes originally sold for $500 az and $600 eq twenty years ago. These had way better optical figures than the cheap achros they are selling now, they are a real steal and very upgradable if you can find one. 

[John]

Neil English (reviewer in UK astro magazines and author of several books on telescopes) tried a Skywatcher Evostar 90mm. He seemed quite impressed with it:

http://neilenglish.net/the-skywatcher-evostar-90mm-f10-achromat/

 

[SIDO]

Here is a cool thread on classic telescope rescue from CN pertaining to the 390/395 Meades, some good reading for sure whatever you should decide or find. https://www.cloudynights.com/topic/485234-meade-90mm-f11-model-390-395-question/

[John]

There are quite a few threads on the Meade 390/395 on the Cloudynights forum:

https://www.cloudynights.com/topic/42212-meade-390395-performance-opinions-please/

https://www.cloudynights.com/topic/395165-meade-390-90mm-refractor-old-or-classic/

Mixed opinions.

Either way, they can only be bought used now and don't turn up often here in the UK.

 

 

[SIDO]

I already stated the 390/395's can only be bought used, all scopes have mixed opinions it's why we have forums. I shared ?

Best of luck....MSammon

[Mike_S]

Thanks, still can’t decide between these two ? I’m not going to rush. The 90/900 is slightly below but very close to the Sedgwick standard or whatever it’s called and the F11 slightly above. Also the Astromaster comes with a red dot finder and the Evostar comes with a 6x30 finderscope. Not used either before. 

[SydBarrett]

Hi all,

 

I have the same question over the https://www.astroshop.eu/telescopes/celestron-telescope-ac-90-1000-astromaster-90-cg-3/p,7891 and https://www.astroshop.eu/telescopes/skywatcher-telescope-ac-90-900-evostar-eq-2/p,5002#tab_bar_1_select

and https://www.astroshop.eu/telescopes/meade-telescope-ac-90-900-polaris-eq/p,51482#tab_bar_1_select

This will be first telescope. I would use it for planets mainly, then galaxy and clouds.

is there a big difference between f10 and f11?

skywatcher comes with Barlow lens. 

Edited August 13, 2019 by SydBarrett