ST102 first (sort of) light

[pakarinen]

I know the ST102 has been discussed, but I thought I'd start a new thread. I tried out the scope a few days ago, but smoke and clouds limited my time to a quick look at Cass to check collimation and such. OTA is quite light, especially compared to my 72ED and ST120.

Took out the new ST102 from about 0320 to 0420 today. Plugged in a 25mm Paradigm to start with and did some sweeping. I think that's where this scope will excel. Stars were reasonably crisp, given my almost corrected astigmatism. There was some distortion on the edge of the FOV, but that wasn't a showstopper.

Stock R&P is smooth enough, but I put on a WO CI diagonal with integrated helical focuser to get a little finer control. I don't think I'll upgrade to a 2-speed just yet.

Took a look at Jupiter. Yow. CA was pretty bad. Added a #8 yellow filter and that helped. I was able to fleetingly make out a couple of equatorial bands at higher mags, but this scope is certainly not a planet killer. And that's ok since I'm not a planetary observer. Next time I'll pop the cap on the objective cover and see how it looks when the scope is stopped down.

Mirfak and cluster - nice wide FOV with quite a few cluster members.
Double Cluster - very nice and stood up to higher mags quite well although the sky was already getting lighter.

All in all, I'm happy with the purchase and expect this will supplant both my ST80 and ST120. I'm not sure I like the white tube rings though - might have to paint those black.

Cheers!

[messier 111]

I like this kind of report, I am happy to see that you like this telescope.
the ca is perhaps due to the eyepeice, I had this problem with a telescope before, a 102 lunt which is a copy made by several resellers.
thx.

[Bigzmey]

Congrats on the first light Olen! Those short tubes are not planet killers, but certainly fun scopes. Stopping the aperture down will help a bit with lunar and planetary.

[helicon]

Nice report and congrats on the first light Olen.

[pakarinen]

I tried stopping down the aperture this morning and had a look at Jupiter, but there was high humidity and smoke in the air (again) so I'm not sure it was a fair test. No matter - if I really want to do some planetary, I'll use my 72ED.

[Lady Fraktor]

I have not tried the 102mm f/5 but have had a few 102mm f/6.5 over the years, fun telescopes for sweeping and viewing.
You may find that with the helical focuser a two speed is not required.

[pakarinen]

I have not tried the 102mm f/5 but have had a few 102mm f/6.5 over the years, fun telescopes for sweeping and viewing.
You may find that with the helical focuser a two speed is not required.

.
I hope that will be the case. A GSO-86 2-speed Crayford lists for US$180 or so, so using my WO diagonal would let me use that money for something else.

[Lady Fraktor]

Being f/5 the focus depth is quite short so I would expect the helical to work just as well as a two speed for you.

[John Baars]

Being f/5 the focus depth is quite short so I would expect the helical to work just as well as a two speed for you.

It does!
(Sorry I'm a bit late)

[pakarinen]

I should have followed up - the helical focuser on the diagonal works quite well. I see no need to replace the R&P.

[SkySurfer]

Thanks for the update. I went the other route and swapped in an Astro Essentials crayford. The stock focuser was adequate, but like you, I wanted a bit more control, and now this lovable little scope even more fun. I also found a 112mm lens cap so I can remove the dew shield to make it even more compact for travelling and storage. Very happy with this scope

[Ylem]

I always wanted one of those, perfect size and more capable of the st80.

Enjoy

[Lady Fraktor]

I have never been much of a fan of the 80 mm f/5 refractors.
To me you may as well get a set of binoculars if just using it as a G&G.

[helicon]

I'm partial to refractors of f/7.5 or greater because of the higher quality views with less chromatic aberration.

[Bigzmey]

True, in terms of optical quality short tube F5 achros lag behind slower fracs. But because of their light weight and compact size they make nice grab and go and DSO scopes and for occasional planetary or lunar you can always stop them down.