TS-Optics Photoline 90mm f/6.6

[jadcx]

I bought this second hand, but it was almost untouched, and a relative bargain to boot.  New it costs 1199 EUR from TS (approx. £1035 as of 08/03/2019 but who has any idea how this might fluctuate).

 

Highlights:

• Apo air-spaced triplet with FPL53
• Multiple focus positions thanks to removable tube segments
• 2.5” rack and pinion focuser, rotatable, dual speed controls, 6kg payload, with printed scale
• CNC tube rings and dovetail supplied
• Retractable dew shield

 

First impressions:

It’s a really nice box.  Whilst it’s described as a ‘transport case’ the supplied storage box is sturdy and well made.  Inside, the foam fit is precise bordering on tight.  It’s actually mildly difficult to get the scope out of the box.  Things get a little easier if you loosen the tube rights slightly, allowing for some tube rotation, and a longer term fix will be some straps to aid lifting the scope out vertically.

The scope itself feels very well made, and is what I’m choosing to refer to as ‘reassuringly weighty’.  At just over 4kg (without diagonal, eyepiece, or finder) there are definitely lighter options available, but it’s hardly a heavyweight.  The finish is powered coat white, which looks and feels very nice.

The focuser is very smooth (compared to my SW ED80) and feels pleasingly solid.  I’m not going to be testing the stated 6kg payload any time soon, but I can easily believe it will be able to handle it.

The dew shield is held in  position with a single thumbscrew, and whilst it’s retractable credentials are clearly warranted, it only seems to extend a couple of centimetres.  As it happens, this takes the overall length down to 450mm which was the very top end of my acceptable range in order to meet my ‘travel’ requirement.  The focuser body also incorporates a finder shoe, but if you wanna  finder then you have to supply your own as there’s nothing included.

The idea of having additional tube segments is that you don’t have to rack out the focuser so far, and so improves stability.  This also allows for multiple reducer/flattener options for imaging use.  The TS website details the specific configurations using their recommended equipment which provide a faster f/4.9 option for sensors up to 36mm, or a full frame flat image at the standard f/6.6.  I might be exploring these options later, but for now, this is going to be for visual use.

 

First light:

OK - this barely counts, but I was impatient.  Predictably enough, first evening with a new telescope and it’s raining.  But I did manage a pretty decent look at my neighbours TV aerial and chimney stack.  They need some re-pointing.

…

The following evening (9th March 2019) was less rainy, but much the same for cloud, all but for about 30 minutes of relatively clear sky, interrupted regularly by patchy cloud.  So still not great.  However, my ambitious setup to allow for cooling paid off and I did manage a few minutes of actual use with a SW 28mm eyepiece.  The Baader Zoom I also treated myself to for my travel use is frustratingly still not dispatched.  And when I say set-up, I mean just carrying everything outside.  I’m using this on the SW AZ-Gti mount, and a Manfrotto tripod I had already, so it’s very easy to pick up and take outside.

I was using the scope with one of the two removable sections in place (this is how it is stored in the supplied case) and was able to achieve focus with a 2" diagonal without having to rack out excessively.

Sirius was an obvious target to the south, and an easy hit.  Brilliantly bright, as expected, and a blue-ish white colour.   The upper half (the rest was below my sightline from home) of Canis Major was easy to see, with several of the background stars also visible.  Despite the less than great seeing, the view was impressive.  Stars were tight and there was no obvious chromatic aberration.   Moving up to Betelgeuse, it’s orange-red brilliance was very pleasing, and again I was able to make out some of the fainter surrounding stars.

Overall the view was very impressive, and bright.  My only real comparison is with my SW80, and of course I now have over 25% more light, so that’s to be expected.  But still, it makes an obvious difference.  I wasn’t able to note any CA or distortion, and a quick full visible spectrum (no filters) star test reflected spot on collimation and no apparent astigmatism.

Alas, the break in the patchy clouds did not last long, and I was soon packing up for the night and heading out for a beer.  I’m looking forward to getting some more quality time with this kit, and who knows, I might even align the AZ-Gti next time and write a brief review for that too.

[mikeDnight]

That's a bonney looking refractor Justin. It doesn't really matter that it clouded over, as you can just sit looking at the scope and imagine what fun youre going to have together. 

[jadcx]

10 minutes ago, mikeDnight said:

That's a bonney looking refractor Justin. It doesn't really matter that it clouded over, as you can just sit looking at the scope and imagine what fun youre going to have together. 

As enjoyable as that may be, I'd rather be outside  

[dweller25]

@jadcx

Great looking scope - the 2cm dewshield extension does not sound much but how much depth does this give to the front of the optics ?

[johnturley]

1 hour ago, jadcx said:

 

The idea of having additional tube segments is that you don’t have to rack out the focuser so far, and so improves stability.  This also allows for multiple reducer/flattener options for imaging use.  The TS website details the specific configurations using their recommended equipment which provide a faster f/4.9 option for sensors up to 36mm, or a full frame flat image at the standard f/6.6.  I might be exploring these options later, but for now, this is going to be for visual use.

 

 

The focuser looks similar to the Explore Scientific 2.5 in Hex Focuser, which has just 45 mm of travel.

John

[jadcx]

9 minutes ago, dweller25 said:

@jadcx

Great looking scope - the 2cm dewshield extension does not sound much but how much depth does this give to the front of the optics ?

There is approx. 23mm from the front of the lens to the end of the tube (with the printed text in picture), and fully extended the dew shield adds a further 36mm.  And wow it looks dusty!

 

[jadcx]

5 minutes ago, johnturley said:

The focuser looks similar to the Explore Scientific 2.5 in Hex Focuser, which has just 45 mm of travel.

John

I don't know about the ES comparison, but with this you get 80mm travel.  I achieved focus with one tube segment and a diagonal at approx. 51mm.

 

[johnturley]

No, I see from the photo that its quite a bit different with a much more adequate 80 mm of travel, the first photo gave the impression of a hexagonal shape, but it looks like that it was just an effect of the light.

John

[jadcx]

8 minutes ago, johnturley said:

No, I see from the photo that its quite a bit different with a much more adequate 80 mm of travel, the first photo gave the impression of a hexagonal shape, but it looks like that it was just an effect of the light.

John

Yes it's definitely cylindrical.

[Stu]

Nice scope @jadcx!

I nearly bought it on two occasions so you saved me from myself! Thanks!

[jadcx]

12 minutes ago, Stu said:

Nice scope @jadcx!

I nearly bought it on two occasions so you saved me from myself! Thanks!

So third time lucky, right?

You know you want to.

[Stu]

Just now, jadcx said:

So third time lucky, right?

You know you want to.

Maybe so. It was a very good deal so you did well. I suspect will end up with one at some point though, specifically for travelling.

[dweller25]

16 hours ago, jadcx said:

There is approx. 23mm from the front of the lens to the end of the tube (with the printed text in picture), and fully extended the dew shield adds a further 36mm.  And wow it looks dusty!

 

Thanks for the info ?

[Highburymark]

Lovely looking scope - I considered it as well before realising that because I already have 80mm and 100mm refractors, perhaps a new 90mm refractor wasn't the most imaginative way forward. Triplet, good for imaging and visual, and I presume aircraft cabin friendly - it's the perfect travel scope.

[jadcx]

4 hours ago, Highburymark said:

Lovely looking scope - I considered it as well before realising that because I already have 80mm and 100mm refractors, perhaps a new 90mm refractor wasn't the most imaginative way forward. Triplet, good for imaging and visual, and I presume aircraft cabin friendly - it's the perfect travel scope.

Yes, it’s all of the above   and whilst I do have an 80mm I’ve justified it because of its travel credentials and “the other one is set up for imaging” which is apparently a believable reason.

[Highburymark]

2 hours ago, jadcx said:

Yes, it’s all of the above   and whilst I do ha e an 80mm I’ve justified it because of its travel credentials and “the other one is set up for imaging” which is apparently a believable reason.

Excellent reasons! Fully justified. Though looking at the pictures you don't need to justify it.