TS Optics 102ED FPL51 - Any info/reviews/users?

[parallaxerr]

Having had a massive astro draw down last year, I'm back to observing with the little Opticstar 80mm F7.5 achro. I'm pleased to say that going back to basics has really sparked my enthusiasm again, actually spending proper time glued to the ep "observing" and not messing with electronics and setting up/stripping down a large setup.

Having said that, the Orion Tritech II fluid head tripod is not up to the scope and vibration has proven frustrating, so I ordered an AZ4 with steel legs today. They're so well renowned at such a reasonable price it was hard to resist.

I've gone from an 80ED to 120ED and back to an 80mm refractor and I think it's clear now that I need to split the difference and settle for a one scope does all 4" ED.

So, the TS102ED, FPL51 version. What's the deal? I've found plenty of reference to the FPL53 version but nothing for the cheaper version. It's available for €599 which is very reasonable, but I wonder if it's any good? I can handle a small splash of colour, most importantly what I'd like is a good figure to take high mags on planets and sharp stars ( the achro is a little asigmatic, which is bugging me). Anyone have experience of this scope?

http://apm-telescopes-englisch.shopgate.com/item/33393133

 

 

[Neil27]

I'm interested in something along these lines myself Jon.

I think it's very similar to this scope from Altair astro - https://www.altairastro.com/ASCENT-102ED-F7-Refractor-Telescope-Geared-Focuser.html

I'm sure it would perform as a reasonable 'all rounder' and be quite acceptable on planets even at high(ish) magnifications.

Just waiting for my bonus to drop and i'll be getting one or something very similar.

 

[Louis D]

You might check for reviews of the AstroTech AT102ED on Cloudy Nights.  I think it is similar to the TS102ED.

[parallaxerr]

6 minutes ago, Neil27 said:

I'm interested in something along these lines myself Jon.

I think it's very similar to this scope from Altair astro - https://www.altairastro.com/ASCENT-102ED-F7-Refractor-Telescope-Geared-Focuser.html

I'm sure it would perform as a reasonable 'all rounder' and be quite acceptable on planets even at high(ish) magnifications.

Just waiting for my bonus to drop and i'll be getting one or something very similar.

 

Well blow me, for all the looking around, I hadn't noticed that one, only the more expensive FPL53 version. Nice that AA have included it in their new range and at that price I may as well buy from the UK! Also waiting for bonus to drop in 5 days

Edited February 15, 2019 by parallaxerr

[parallaxerr]

10 minutes ago, Louis D said:

You might check for reviews of the AstroTech AT102ED on Cloudy Nights.  I think it is similar to the TS102ED.

Some good reviews there. To say CA was there  but only if looked for at x200 on Venus suggests it's more than acceptable for visual

[Louis D]

I have the original FPL-51 version of the AT72ED, and I only see purple fringing up around 125x on bright stars.  I don't see it on the moon or planets at sub-100x powers.  It looks pin sharp and color free at low powers when scanning star fields, which is the main thing I use it for.  I haven't tried looking for color fringing on high contrast daytime targets like dark tree limbs against the bright sky.

[vlaiv]

I don't think you'll go wrong with this one:

https://www.altairastro.com/Starwave-102ED-FPL53-Refractor.html

I think it's the same optics as this:

https://www.teleskop-express.de/shop/product_info.php/info/p9868_TS-Optics-PhotoLine-102mm-f-7-FPL-53-Doublet-Apo-with-2-5--Focuser.html

Or this one:

https://www.stellarvue.com/stellarvue-sv102-access-ed-apo-refractor-telescope/

Old FPL-51 version was also branded by Altair Astro, now only sold by TS as the scope you linked to in the first post. FPL-51 one shows CA on brighter targets, and I remember reading one review where it showed pinched optics.

Here is review of it (AA version): https://www.altairastro.com/public/reviews/Starwave-102ED-Review-Sky-at-Night-Magazine-Issue-86-4_stars.pdf

I think that new version with FPL-53 glass is better choice if you can afford it. I've been interested in that scope for quite some time now (waiting for funds to become available to get one for myself). According to reviews, optics on that model should be really good.

I think that FPL-51 is still good scope for the money. 100ED will surely show better image, but 102 F/7 will be more portable, easier to mount and will have better focuser. It will also show wider view. I would call it a compromise.

FPL-53 one I would not call compromise, I believe it will show the same quality image as 100ED with all mentioned advantages - wider field, shorter physical length and better focuser.

[mikeDnight]

I think paulastro has the original version of the Astro Tech 102ED.  I've used it numerous times and the one thing that strikes me when thinking about it, is that nothing strikes me! In other words, if the CA were objectionable I would definitely have noticed it. If the star images were anything but perfect it would have jumped out like a sore thumb. And if its lunar and planetary performance was In anyway lacking, I would definitely have noticed it!

Consider also that Paul's scope had its focuser replaced with a feathertouch by its original owner. It must have been very highly thought of as noone would go to that expense for a mediocre scope. Also, Paul regularly observes with me using his AT ED alongside my Tak FC100DC and the two scopes get along fine. There is no rivalry between the two and they play pretty on all targets. 

I think a 4" ED is an excellent scope for a serious observer who likes a portable, easy to use, yet very capable all round wide field/lunar/planetary/binary star instrument. Often excelling well beyond their aperture class, a 4" refractor could be the only scope you'll ever need! Whether its the only scope you'll ever want is another matter!

Just a quick point on glass types. Years ago manufacturer's didn't necessarily disclose the glass type used in their scopes. I've used a few old Vixen ED's long and short and they were all superb! Today it seems everyone worries a little too much about things they really don't need to worry about. Strehl for example: could anyone really tell the difference between a strehl of say .97 and .99?  What i do know is that if you want to add colour to a refractor image, use a Nagler eyepiece and look at the Moon. I wonder how many good apo's have received bad press that way? 

 

 

Edited February 15, 2019 by mikeDnight

[parallaxerr]

Interesting points from you all. Vlaiv, I can't argue with anything you say, however, I have previously found myself drawn in by specs and paralysis by analysis, leading me to overspend. For what I have in mind, £1000 is just too much. Frankly, I had every intention of buying a longer achro but fear the wobbles and when I started looking at a Vixen 105, I realised I was into ED prices. If an FPL53 version comes up on the used market of course, then it's a no-brainer. Actually, there's a rather nice Stellarvue with a FT focuser on ABS but again, it's pushing what I call my acceptable budget.

Mike, what you have to say is encouraging. As you know I had the Equinox 120 and mounting requirements were my issue. I got there in the end and had a lovely setup but it didn't move from the office due to the size & weight. It's the reports of people stepping back to a 4", especially Taks, much like yourself and claiming that a) they get more use and b) they don't really miss the aperture that make me think it's the way to go. Sadly, I can't justify a Tak but if the scopes I'm considering fare well in the company of an FC, then I'm sure one will be fine for me.

After all, I am but a mere amateur and I very much enjoyed my Sky-Watcher ST120, which many claim had absurd levels of CA (not to my eye, at least with a bit of filtering). It was excellent for deep sky where colour wasn't an issue and I seriously considered another, but if I want to cover planets too, I either need to add a second scope, like a Mak, or go ED and I'd really rather just stick with one. 

Plenty of food for thought, I'll keep researching but that AA version has proper caught my eye....

 

 

[mikeDnight]

There's always the Star Wave ASCENT 102ED  F11 if you want that tad better colour correction, but I'm sure the Astro-Tech  F7 will do amazing things, and with a wider/richer field!

[parallaxerr]

2 minutes ago, mikeDnight said:

There's always the Star Wave ASCENT 102ED  F11 if you want that tad better colour correction

Same thoughts here, but I have reservations about the length. Last thing I want is to have to up-mount again.

[parallaxerr]

13 hours ago, mikeDnight said:

I think paulastro has the original version of the Astro Tech 102ED

I just found the thread where you discuss it Mike, I must say the AT looks just perfect on the AZ4

 

[mikeDnight]

As Paul mentions in his short review, "you have to look for the false colour"! You mentioned earlier Jon, that the colour in the SW Star Travel didn't bother you much. Well the colour in the Astro Tech is in a whole different league to that of the Star Travel.  Does this mean you're going to become the daddy of a new 102ED?  Shall I break out the cigars??

Just take a look at it once again.......  And don't forget that happy chap who owns it! 

The tube assembly looks physically larger in the pic than it does in the flesh, due to perspective. 

Edited February 16, 2019 by mikeDnight

[paulastro]

On ‎15‎/‎02‎/‎2019 at 20:07, mikeDnight said:

I think paulastro has the original version of the Astro Tech 102ED.  I've used it numerous times and the one thing that strikes me when thinking about it, is that nothing strikes me! In other words, if the CA were objectionable I would definitely have noticed it. If the star images were anything but perfect it would have jumped out like a sore thumb. And if its lunar and planetary performance was In anyway lacking, I would defiinitely have noticed it!

Consider also that Paul's scope had its focuser replaced with a feathertouch by its original owner. It must have been very highly thought of as noone would go to that expense for a mediocre scope............

 

 

Mike, this isn't quite accurate.  The FT focuser came with the scope when it was sold new - nearly eleven years ago.  I have the original invoice.   It was fitted from new, and says  on both sides of the focuser that it was made for both Astro-Tech and for this particular telescope.  The focuser has a 9:1 reduction fine focus.  The original price when bought new on 21st April 2008 was £825 including VAT.  It was sold in this country by SCS Astro Ltd.  The scope also came with a nice hard case which I still have.

[paulastro]

23 hours ago, parallaxerr said:

Same thoughts here, but I have reservations about the length. Last thing I want is to have to up-mount again.

Apart from the physical length of course the focal length is much longer,  the optimum focal ratio for a four inch refractor is f7 for me.  This is because I like to do widefield sweeping as well as planetary, and the combination with my 17.5mm Morpheus is made in heaven for me - literally .

[mikeDnight]

Thanks for the correction Paul. So the manufacturer's felt the scope was worthy enough to warrant a top class focuser. That's got to be a good indicator! ☺

[parallaxerr]

18 hours ago, mikeDnight said:

Does this mean you're going to become the daddy of a new 102ED?  Shall I break out the cigars?? 

Well, it is certainly top of the list Mike. I can't help thinking about another ST120 purely for the aperture for DSO, which makes up 95% of my observing, but I'd want to upgrade the focuser which would push the spend to the same as a new AA 102ED. Also, from experience I know that option would weigh over 1kg more than the spec weight for the 102, which may push the AZ4 beyond the level of stability I'd like.

I guess I'm trying to convince myself that I wouldn't miss the extra aperture, though many argue that the better colour correction and figure of the glass would negate it.

 

[John]

17 minutes ago, parallaxerr said:

.. though many argue that the better colour correction and figure of the glass would negate it.

 

It would for planetary / lunar/ double star viewing but not really for observing DSO's.

[Stu]

How about this one? Same scope I assume but with an FT focuser for £600. What's not to like?

https://www.astrobuysell.com/uk/propview.php?view=146651

[parallaxerr]

23 minutes ago, John said:

It would for planetary / lunar/ double star viewing but not really for observing DSO's.

Just when I thought I had it all worked out! I must admit, the ST120 went much deeper than I ever expected.

If I had another, I'd have to upgrade the focuser so the cost would be near the same as the 102ED. From experience I know this would put the scope at least 1kg over the specified 102 weight and I've become very sensitive to vibration, so I fear the 120 may push the AZ4 a bit further than I'm comfortable with?

16 minutes ago, Stu said:

How about this one? Same scope I assume but with an FT focuser for £600. What's not to like?

https://www.astrobuysell.com/uk/propview.php?view=146651

It's on the radar Stu, the FT is very alluring. I wonder how old the scope is? May have to enquire. Enquiry sent.

Edited February 17, 2019 by parallaxerr

[Mark at Beaufort]

I was the original owner of the Astro Tech 102ED before I sold it to Shane. It was brilliant in ever way and I highly recommend this size scope. I only sold it because I had far too many scopes at the time. It still looks great Paul.

[parallaxerr]

1 minute ago, Mark at Beaufort said:

I was the original owner of the Astro Tech 102ED before I sold it to Shane. It was brilliant in ever way and I highly recommend this size scope. I only sold it because I had far too many scopes at the time. It still looks great Paul.

Are you referring to the Stellarvue on ABS Mark, or Pauls Astro Tech?

[rhw1967]

Been following this thread with great interest. Actually been looking at the AA's new ones, both the F7 and F11 as have been mentioned in this post, for myself. Trying to find out a little more info, however cannot find any reviews or anything in depth.

[Mark at Beaufort]

39 minutes ago, parallaxerr said:

Are you referring to the Stellarvue on ABS Mark, or Pauls Astro Tech?

Sorry Jon I was referring to the scope that @paulastronow owns. However, I have had a look the Stellarvue on offer on ABS and it does look very nice. I am sure this is a similar Stellarvue that I looked through in California viewing the Venus Transit 2012. If it the same model it was an excellent 4" Frac.

[paulastro]

27 minutes ago, Mark at Beaufort said:

I was the original owner of the Astro Tech 102ED before I sold it to Shane. It was brilliant in ever way and I highly recommend this size scope. I only sold it because I had far too many scopes at the time. It still looks great Paul.

Mark, good to hear your comments.   I did wonder if you might see this thread and recognise the scope as once being yours.    I agree with your sentiment, I love it and it's performance is fabulous.  I think this particular telescope proves the point that it's not just the type of glass that makes a good doublet, it's far more to do with the quality of the objective in its' manufacture and that it has a well made cell and nicely darkened/baffled tube to accommodate it.  It was in really good condition when I obtained the scope from Shane and I assure you I'll continue to do my best to maintain it in the same way.  Thank you for looking after it so well when you were its custodian .  It's in safe hands.