Very Short Observing Session with the C90 Mak (3-28-20)

[terrynak]

Although tonight was forecasted to be partly cloudy – around 7:30 the skies looked mostly clear, with thin clouds coming in from the west. So I got out my Celestron 90mm Mak and set it outside to be acclimated to the outside temperature:





The mount/tripod is a Vixen Mini-Porta alt-az; the finder scope is 8x40 and originally came with the Orion ST80A (“A” stands for the astronomy version of this scope). The dew shield is made of craft felt.

The scope has been little used since purchase in 2012. The last time I took it out was in mid-2017, just to test collimation and performance on Jupiter and the Double-Double in Lyra (passed with flying colors). Tonight, I wanted to see how it would perform on the Moon and Venus – don’t recall having used this scope on these objects before.

The Moon looked sharp at 39x at brief moments when the wispy clouds passed. The gibbous phase of Venus was sharp and clean at both 39x and 73x with no color fringing – reminded me of the image that Mark (Thefatkitty) showed in his last thread. Probably one of the best (if not the best) view of Venus I had with any of my scopes.

Unfortunately, the skies were socked over after about 15 minutes of viewing, ending the session.

[Graeme1858]

At least you got to see a good view of the Moon and Venus even if only for 15 minutes!

Regards

Graeme

[pakarinen]

How’s that finder down at the 8 o’clock position working for you? My SW 90mm is the same and it’s awkward to use even when I crank my tripod center column up. I guess buying an RA finder would be one solution.

[John Baars]

Well done! Thanks for sharing with us.
My 102mm Mak has a RA finder too, just for my own comfort. Recommended!

[terrynak]

At least you got to see a good view of the Moon and Venus even if only for 15 minutes!

Regards

Graeme

Yup Graeme, it was just good to get this scope out again - pleased with the views!

How’s that finder down at the 8 o’clock position working for you? My SW 90mm is the same and it’s awkward to use even when I crank my tripod center column up. I guess buying an RA finder would be one solution.

Olen, first thanks for purchasing the SW 90 Mak! Your report in the "Skywatcher Telescopes" section of this Forum got me interested in getting my 90 Mak back out again.

Because the alt-az mount I'm using has the dovetail saddle sideways (hence the 8 o'clock position), when the target is even slightly above eye-level, I have to get on my knees to view through the finder scope.

Yup an RA finder would be the best, but using a mount with the dovetail saddle on the bottom (like an EQ mount) would put the finder on top. Another solution is to attach a red-dot finder (Telrad or Rigel Quik Finder) to the side of the scope so that it's on top of the OTA if you're using an alt-az mount with a sideways saddle.

I currently have an unused Rigel Quik Finder, so I might do just that...

Well done! Thanks for sharing with us.
My 102mm Mak has a RA finder too, just for my own comfort. Recommended!

Thanks, you're welcome John! I'll probably go the Rigel finder route if I start using this scope more often...

[helicon]

Sounds like some excellent views Terry - nice and crisp! Glad you could get out there.

[terrynak]

Sounds like some excellent views Terry - nice and crisp! Glad you could get out there.

Thanks Michael! Just reconfirmed that the Mak is a good planetary scope!

[Lady Fraktor]

The C90 can be a fun telescope to have, good that you managed a few minutes out with it.

[pakarinen]

I think I'll try double-side taping the bundled RDF on "top" of the OTA toward the objective. I'm not inclined to buy another RA finder just now. Alternately, I could use the 8x50 from my ST120, but I think I'd rather get another RA finder than swap it back and forth.

[Thefatkitty]

Nice session and scope Terry! I' love to actually see Venus at the scope like that pic... I've often thought about getting a Mak; maybe when all this mess is over

Hope you get more clear skies,

[Juno16]

Thanks for sharing Terry!

Sounds like a pretty cool scope. That scope would be nice to pull out pre-dawn to check out the planet trio!

[terrynak]

The C90 can be a fun telescope to have, good that you managed a few minutes out with it.

Thanks Gabrielle - yes I'm glad I have this in my (large) stable of scopes!

I think I'll try double-side taping the bundled RDF on "top" of the OTA toward the objective. I'm not inclined to buy another RA finder just now. Alternately, I could use the 8x50 from my ST120, but I think I'd rather get another RA finder than swap it back and forth.

Re: RDF finder with SW 90 Mak - interesting My C90 Mak originally came with a 8 x 21 finderscope which I swapped with my Orion ST80A's more generous 8 x 40. I know the backpacker version of the SW 90 Mak (available earlier in the previous decade) originally came with the same 8 x 21 finderscope.

Nice session and scope Terry! I' love to actually see Venus at the scope like that pic... I've often thought about getting a Mak; maybe when all this mess is over

Hope you get more clear skies,

Thanks Mark! Didn't know that you didn't own a Mak...

Thanks for sharing Terry!

Sounds like a pretty cool scope. That scope would be nice to pull out pre-dawn to check out the planet trio!

Yes it is Jim. I definitely would like to do more planetary observing with it, along with deep sky as well. In fact, the limited times I used it in the past was for deep sky (I found two "new" planetary nebulae with it).

[Bigzmey]

Nice quick session Terry! I like your dew shield.

[terrynak]

Nice quick session Terry! I like your dew shield.

Thanks Andrey!