Jump to content

Stargazers Lounge Uses Cookies

Like most websites, SGL uses cookies in order to deliver a secure, personalised service, to provide social media functions and to analyse our traffic. Continued use of SGL indicates your acceptance of our cookie policy.

sgl_imaging_challenge_banner_christmas_presents.thumb.jpg.587637e0d01baf4b6d21b73610610bbb.jpg

DevonSkies

Thoughts on the Startravel 102

Recommended Posts

I have been using a Skywatcher Startravel 102 for about a month now as a grab-and-go scope. I also intend to use it as a travel scope for holidays, but I've yet to try it in that capacity. So I thought I'd record some of my thoughts about this scope.

Initially I purchased the ST102 with an AZ3 alt-azimuth mount, but I quickly found I didn't get on with the AZ3. On the plus side, it is very compact and lightweight and would make an excellent travel mount. However, I found the friction bolt arrangement for setting the altitude tension to be unreliable, and the mount was difficult to use near zenith. So, I changed the mount to a Vixen Porta II, which is much more comfortable to use. The Porta II tripod does seem to vibrate a bit more than the AZ3 though (especially on concrete), so maybe I will change the legs for something more substantial one day.

Onto the telescope itself. The optical tube feels very solid and substantial. There is a large dew shield fitted, which is held on with a simple push fitting held in place by a felt band. Removing the dew shield reduces the OTA length significantly, but unfortunately the supplied lens cap won't fit over the front cell without the dew shield in place. This is a pity, as removing the dew shield would make the scope very compact for travel.

The 102mm doublet objective has a blueish-looking coating, that seems evenly applied. The OTA assembly is supplied with decent tube rings and a dovetail. If you buy the scope in a kit with the AZ3 mount it comes without a dovetail, and the tube rings bolt straight onto the mount.

The focuser felt quite smooth but a little tight straight out of the box. Initially there was no play in the focuser and the drawtube was well aligned. However, the focuser does prove to be a weak point on these scopes and I will return to this later.

Now on to the important bit - performance! The OTA came supplied with the usual 25mm and 10mm MA eyepieces. The 25mm is quite a good budget eyepiece, but the 10mm could be better. However, since I already have a set of reasonably good eyepieces I put the supplied EPs to one side. Also supplied with the OTA and AZ3 kits is a 45-degree erecting prism. This is useful for terrestrial observation, but not really of sufficient quality for astronomical work (although it is OK at low magnifications). I replaced this with the excellent Revelation 2" Quartz Dielectric diagonal.

This scope excels at wide-field views of open clusters and brighter DSOs. With a 25mm X-Cel LX eyepiece the whole of the Pleiades can fit in the field of view, which is a stunning sight. I also have a 32mm Panaview 2" eyepiece, which offers a whopping 4.4 degree field of view, framing the Pleiades beautifully within the surrounding sky. Under a dark sky the view is quite breathtaking. Other open clusters such as the Beehive also look superb with such a wide field. Best of all, this scope gives me the best view I've had of the Double Cluster in Perseus, with both parts of the cluster beautifully framed within the FOV.

Large DSOs are also a strong point for this scope. M31 (Andromeda) looks fantastic under a dark sky, and dust lanes are visible. Dimmer DSOs are quite within the reach of this instrument, with M1 (Crab Nebula), M33 and M51 all visible under dark skies. Globular clusters also make good targets, although perhaps a little more aperture would be useful here to see them at their best.

Working at high magnification, the ST102 is quite capable of splitting the "easier" double stars such as Castor and Sigma Orionis. A 5mm EP works well here, and a Barlow can help to increase the separation on brighter doubles. The dim companion to Rigel can just about be made out under good seeing conditions.

You may notice that I haven't mentioned CA (chromatic aberration) yet. That's because, for clusters, DSOs and most double stars it simply isn't an issue. For planets and lunar observation, however, it's a different matter. Yes, the dreaded purple haze is there, especially noticable on the limb of the moon and on bright planets such as Jupiter. In fact, the ST102 is quite capable for casual lunar and planetary observing, but if the solar system is a primary interest for you then you might look elsewhere. Although the optics are pretty sharp at high magnification, I really feel that the CA damages the contrast for planetary and lunar observation.

This is my first refractor (my other scope is a 10" Dob). I have to say I'm now a refractor fan! There's something about the ease of setup and the contrasty, pinpoint stars that appeals to me. I also like the short-tube concept from a portability point of view, and these scopes are very capable deep sky instruments. Yes, CA is a problem on bright objects at high magnification, so it's not an all-rounder like an APO, but for the price it's fantastic value for money.

I mentioned the focuser earlier. After some use, the focus tube developed some vertical play. There are two grub screws on the top of the focuser which are used to tension the drawtube. I needed to tighten the front (i.e. closest to the objective) screw to take up the slop, and also tighten the rear screw to remove any remaining image shift. After this adjustment the focuser worked fine again. I have now had to do this twice, so it seems that periodic adjustment is required. After the second adjustment cycle the focuser was very stiff, which I resolved by slackening off the screws that tension the spring in the focus pinion assembly. Now the focuser is nice and light and smooth, but I anticipate further adjustments will be necessary in future. We shall see! This is really a faff and the only real annoyance with this scope. There is a dual-speed Crayford focuser available which is a drop-in-replacement for the original R&P focuser, but at around £129 I'm not sure it's worth it on an OTA costing £169!

All in all, I really like this scope, apart from the cheap focuser. In fact, I like it so much I'm wondering what the 6-inch ST150 would be like on DSOs and clusters!

Ed

  • Like 9

Share this post


Link to post
Share on other sites

Great review and a great read. i have the 120mm Evostar which is a great scope and i absolutely love it. it has sligh Ca but i can handle that. all the best and enjoy. Scott

Share this post


Link to post
Share on other sites

Excellent review Ed - really brings out the charactistics of this scope very clearly :icon_biggrin:

I think the 150mm F/5 would show substantially more CA as that increases as the aperture increases. It would still be a very nice deep sky / rich field type scope though.

According to this table, your 102mm F/5 will be showing about as much CA as my 150mm F/8 shows:

 

CA-ratio-chart-achro.jpg

  • Like 1

Share this post


Link to post
Share on other sites
10 minutes ago, John said:

Excellent review Ed - really brings out the charactistics of this scope very clearly :icon_biggrin:

I think the 150mm F/5 would show substantially more CA as that increases as the aperture increases. It would still be a very nice deep sky / rich field type scope though.

According to this table, your 102mm F/5 will be showing about as much CA as my 150mm F/8 shows...

 

mmmm.... 150mm f/8... now there's a thought! Not sure I could justify it alongside the 10" Dob though!

 

Share this post


Link to post
Share on other sites

A good field review of these short tube refractors, they have a lot going for them.  Especially with our climate being so changeable, as you often have a short viewing window before the clouds roll in.  For really bright objects like Venus or the Moon, the inbuilt mask works well at reducing excessive glare.  What i did with my porta mount, was to cut a slit in some tennis balls, although it looks it bit odd, they did cut the vibrations down !

 

andrew

porta.jpg

  • Like 4

Share this post


Link to post
Share on other sites

Thats a nice review.

I had an 102 and was quite pleased with it. I did buy a fringe killer filter which helped on Lunar and planetary.

If you look at most Skywatcher reviews the 10mm stock EP always seems to be the one that gets criticised.

I mod'd the focuser on mine for a 10:1 type from Telescope Service in Germany. It worked well but I had to add an extra spacer as there was not quite enough backward focus with a DSLR.

 

Share this post


Link to post
Share on other sites
1 hour ago, andrew63 said:

A good field review of these short tube refractors, they have a lot going for them.  Especially with our climate being so changeable, as you often have a short viewing window before the clouds roll in.  For really bright objects like Venus or the Moon, the inbuilt mask works well at reducing excessive glare.  What i did with my porta mount, was to cut a slit in some tennis balls, although it looks it bit odd, they did cut the vibrations down !

 

Good idea, I might try something like that.

Also a good point about the aperture mask for moon and planets. I've found it virtually eliminates CA, but it does cause some loss of resolution.

I forgot to add that I have also tried the Baader Contrast Booster filter, which is supposed to be the most aggressive of the CA-reducing filters. Although it did noticeably reduce the CA, it left a yellow cast which I found unpleasant and also noticeably reduced the sharpness of the view at high magnification. In the end I decided I preferred the unfiltered view! At some point I will probably buy a dedicated grab-n-go for lunar/planetary work (maybe a Mak or an f/10-ish refractor).

Edited by DevonSkies
Typos

Share this post


Link to post
Share on other sites

Great review and sums up pretty much how i feel about my ST102. I have had it for a good number of years now and in fact use it on a Porta II mount myself.

However, it is going to be surplus to requirements shortly as i am waiting for............................an ST120 to arrive :-)

I use a semi-apo filter in my diagonal and it works quite well, it does impart a slightly yellow cast to the view though. But i can live with that.

  • Like 1

Share this post


Link to post
Share on other sites
49 minutes ago, Bobby1970 said:

Great review and sums up pretty much how i feel about my ST102. I have had it for a good number of years now and in fact use it on a Porta II mount myself.

However, it is going to be surplus to requirements shortly as i am waiting for............................an ST120 to arrive :-)

I use a semi-apo filter in my diagonal and it works quite well, it does impart a slightly yellow cast to the view though. But i can live with that.

I do wonder whether I actually should have got the ST120 in the first place. I was undecided between the two when I made the purchase, and decided on the 102 because I thought it would be more portable. But in the end the ST120 is only 10cm longer and 2cm wider, and for DSOs one needs all the aperture one can get!

I'd be interested to hear how you think it compares to the 102 when you get it. Will you have the chance to compare side by side?

Share this post


Link to post
Share on other sites
58 minutes ago, DevonSkies said:

I do wonder whether I actually should have got the ST120 in the first place. I was undecided between the two when I made the purchase, and decided on the 102 because I thought it would be more portable. But in the end the ST120 is only 10cm longer and 2cm wider, and for DSOs one needs all the aperture one can get!

I'd be interested to hear how you think it compares to the 102 when you get it. Will you have the chance to compare side by side?

Yes. I will. I am very much looking forward to comparing all aspects of the two scopes. I will let you know how it goes. 

  • Like 1

Share this post


Link to post
Share on other sites
55 minutes ago, Bobby1970 said:

Yes. I will. I am very much looking forward to comparing all aspects of the two scopes. I will let you know how it goes. 

Thanks. I'll look forward to hearing how you get on! 

Share this post


Link to post
Share on other sites
On 1/26/2016 at 05:00, andrew63 said:

A good field review of these short tube refractors, they have a lot going for them.  Especially with our climate being so changeable, as you often have a short viewing window before the clouds roll in.  For really bright objects like Venus or the Moon, the inbuilt mask works well at reducing excessive glare.  What i did with my porta mount, was to cut a slit in some tennis balls, although it looks it bit odd, they did cut the vibrations down !

 

andrew

porta.jpg

I put tennis balls on the bottom of my Celestron 127 SLT tripod and they do seem to help dampen vibrations. Another side benefit is that the tennis balls are visible in the dark so I don't trip on my own mount!

Share this post


Link to post
Share on other sites

Concur with all you've said about the 102. Great little scope although it does produce a little more CA than my evo 120 achro.

Share this post


Link to post
Share on other sites

Good little scopes these. I went for the 80mm as I wanted something really portable and have been pleased with it. It's poor on planets, but with the Baader semi apo filter the lunar views are actually quite good. 

Share this post


Link to post
Share on other sites

I've had a 102 for a couple of months now. Bought it to use for solar observing, but also use it for a grab and go option. I really like it. Lovely FOV for extended objects and really good for some doubles. CA is there, but I do not find it too obtrusive.

Share this post


Link to post
Share on other sites

Just seen this thread and , just in case it’s still relevant , I have a 102 , which I bought about 6 years ago . It didn’t get too much use at the time but I’m completely hooked on astronomy now and , although I’ve bought another refractor (wo z73) which is ultra portable , I still use my 102 , with its goto az mount . I think this  scope is one of the most practical I’ve used . Good for DSO and planets (despite the ca) ... i purchased an eq5 mount which now aids stability , I agree about the focuser , mine seemed to “jump” a bit which can be annoying . I also thought about dropping in a Crayford , but , as I now have the z73 I don’t think it’s going to happen . 

A great review 

Share this post


Link to post
Share on other sites

Very good review. I bought a similar unit, the Bresser AR-102xs off another SGL member as my main travel/holiday scope. I have it on a SkyWatcher AZ Pronto mount on top of my old trusty Manfrotto 055CL tripod (better build quality and stability than the stock SW aluminium tripod). The setup is very light weight and can be assembled/disassembled within minutes.

 

The visual experience so far pretty much matches this review. The stock 26mm S.Plossl gives a nice wide FOV for bigger/brighter DSOs like M31 and M45. I also use BST Starguiders 5mm and 12mm for smaller DSOs (e.g. M57) and Doubles. Last night I tried the scope on the Moon with the BST 5mm. The view while being a bit soft for my taste and containing visible CA halos was better than expected. The lunar/planetary performance while being no match for my 4" APO triplet (my main scope for lunar/planetary and general imaging) is surprisingly satisfactory for a fast ultra portable achro.

Share this post


Link to post
Share on other sites

It's nice to hear your views on the ST102. It really is a capable grab and go rich field refractor, which when used for its intended purpose, which is low power wide field views of nebulae, clusters, comets and fabulous rich star fields. As far as its lunar and planetary ability is concerned, it's not designed for such observing. It is after all a specialist instrument that probably gets bad press because it low price, short focal length and achromatic design. I have to say I have a soft spot for the ST102, but an even softer spot for its big brother the ST150, which is a superb RFT. I wouldn't be put off buying a ST150 because of reports of its CA level. You will only notice the CA on the brightest stars. It's RFT ability is breathtaking! 

Share this post


Link to post
Share on other sites

I got one of these as my first refractor and despite now having several Fracs, including an ED100 this one still gets loads of use.

To be honest, I don't find the CA too bad, even when lunar observing, but I think that CA annoyance varies from observer to observer, it doesn't bother me much on the example that I have at all.

This little scope has given me some cracking views of the Moon, Jupiter, Saturn, WL Solar and loads of brighter DSOs.  In terms of performance compared to cost, I think that this little OTA scores pretty highly and I'll certainly be keeping mine.

Ade 

  • Like 1

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


  • Recently Browsing   0 members

    No registered users viewing this page.

  • Similar Content

    • By Kronos831
      Hey guys!i need to make this quick! I want to get a new 6mm eyepiece.I have a 8" f6 dob and i want to get a nice 200 mag and put the telescope to its limits at 400x
      The most i ve seen with is 240x for Jupiter and Saturn .i ve heard they looked stunning at 400x and i am keen on trying it.Ive got my eyes on a 6mm Skywatcher UWA eyepiece.and i have a Bst Starguider 2z Barlow lens.And i seem to be having problems with my 8mm Bst Starguider (300x in total).the bst has a 16mm eye relief and a 21mm lens diameter,but when i barlowed it and look at the moon yesterday,it was hard finding the right spot to look through the eyepiece and when i moved the image disappeared.I dont know if it will have that effect on planets,when I looked at mars it was fine but i definitely want to avoid that from happening again.Will it happen?
      The Skywatcher eyepiece i want to buy has a 16mm eye relief too.I dont want to make the same mistake now , i want a 6mm eyepiece at the price range of 50-70 euro either from flo or amazonuk.If the Skywatcher will have similar results,can you suggest another one?
    • By Dinglem
      I've upgraded my focuser so have a Skywatcher Dual-Speed Low Profile 1.25/2" Crayford focuser for sale £70 delivered to UK only.
      Bank transfer or Paypal F&F preferred.
       
       

    • By Owmuchonomy
      Wrapping up in double layer goose feathers I braved the obsy last night.  I planned a tour of Auriga with a view to chucking in some favourites.  I set up the ED150 on the AZ EQ 6 and fitted the WO quartz diagonal accompanied by my ES 20mm 82'.  I stuffed my Astronomik 1.25" UHC (bargain price thanks @FLO) in my pocket too.  This set up required the retro children's playroom chair with the legs sawn down due to the position of Auriga. I spent about half an hour checking the plethora of open clusters sprinkled in or near the Milky Way.  The sky was one of the best this season so it was a jewelled spectacle and the ED150 reveals such sharp colours enabling me to distinguish the cooler stars in some of the clusters particularly the occasional red giant.  As Monoceros reached the meridian I moved to the open cluster associated with the Rosette. Now, for all my efforts over the years, the emission nebulosity has eluded my eyes but tonight with this newish 6" frac I was somewhat taken aback to see a doughnut appear in the view.  Switching to a view with the UHC filter was nothing short of astonishing!  It wasn't just there; I was falling into its centre.  Texture, depth and dark globules were easily discernible.  The extent was slightly larger than the FOV with the 20mm so I slewed slowly around and the perimeters and varying consistency of the Ha emission were easily picked out.  I spent a long and happy time soaking this up; it was truly outstanding.  Thoroughly recommended.  I retired happily to the warm kitchen and toast.
    • By Greg6498
      Hello all!
      I just installed this Lacerta 1:10 Micro Transmission focuser on my 8” Skywatcher Dobsonian. It is a direct replacement for the stock focuser and works extremely well. I was surprised at how easy it was to install! Ordered it from 365Astronomy and got fast shipping.
       


    • By Kronos831
      This is probably my options as of now:I will definetly buy a 12mm BST Starguider A 2X BST Barlow( So thats 100x and 200x magnification) 
      AND Either:
      15MM BST STARGUIDER VS 25MM STARGUIDER
      My dobsonian telescope will include:A 25mm and 10mm Eyepiece . So the obvious awnser is to go for the 15mm BUT i ve read in reviews that the bst s have are noticabely better than the eyepieces that come with my telescope.So i am wondering, should i buy the 25mm or the 15mm BST? 
       
      Also is it worth to barlow either 25mm eyepiece to make 12.5mm and ditch the 12mm i am definetly buying for a 6mm one? i am thinking not because if i barlow the 6 mm it will give me 400x and i think that is too much magnification for the image to appear clear , plus i will also barlow the 10 mm to give me a 240x the acceptable limit for good clarity / magnification ratio (i ve read that and not sure if its true or not). Thanks again for your time and help!
      This forum has been very polite, welcoming and kind to noobs like me just getting into the hobby XD I hope i can one day look back at myself and laugh at my ignorance! This site has been truly amazing and i hope i can stay a member for a long time to come!
      Thanks as always
      Clear skies everyone
      Kronos
×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.