TS Imaging Star71 - 71 mm f/4,9 5-element Flat-Field APO

[gnomus]

What is the difference between this: http://www.teleskop-express.de/shop/product_info.php/info/p7085_TS-Imaging-Star71---71-mm-f-4-9--5-element-Flat-Field-APO-fuer-gro-e-Sensoren.html and this http://www.williamoptics.com/telescopes/2014-WO-Star71-Five-elements_features.php?

[Davey-T]

Nothing 

Dave

http://www.firstlightoptics.com/william-optics/william-optics-star-71-f49-5-element-refractor.html

[knobby]

They look the same to me

[triton1]

I believe their made by WO and then branded TS

[Ibbo!]

something to do with the focuser I think

[gnomus]

something to do with the focuser I think4

That is interesting.  The description of the focuser is similar (if not identical) and the photographs make it look very similar.  Do you remember where you heard this?

[pete_l]

The difference?

• Price (TS have both on their website: €1200 vs €1500)
• availability
• reputation
• sales support
• resale value

basically, the intangibles that a "paper" comparison or review article do not, or cannot, consider.

Whether they are worth paying for is a purely personal choice.

[ollypenrice]

I doubt that there is any way of knowing. The manufacturers of lenses, I'm told, grade their output and it seems unlikely that they would just discard units that were not quite as good as the best. Which of the assemblers get the best and which the rest? Who knows?

What we do know, though, is that some suppliers have better returns policies than others and given the fact that this remarkable scope does not come with a perfectly clean QC record this would be my number one factor in choosing. Don't get me wrong, I think this is a great scope and, if I didn't have this approximate FL covered already, I'd have one.

Olly

[gnomus]

I doubt that there is any way of knowing. The manufacturers of lenses, I'm told, grade their output and it seems unlikely that they would just discard units that were not quite as good as the best. Which of the assemblers get the best and which the rest? Who knows?

What we do know, though, is that some suppliers have better returns policies than others and given the fact that this remarkable scope does not come with a perfectly clean QC record this would be my number one factor in choosing. Don't get me wrong, I think this is a great scope and, if I didn't have this approximate FL covered already, I'd have one.

Olly

Thank you. So do you think it is likely that the TS offering may have lenses of a lower grading than the WO option? [scratch that question. I see you have already answered it with your "Who knows"?]. I notice that TS in Munich also offer the WO version but at 300 Euro more. What I have read about TS as a supplier seems positive - have I missed any postings to the contrary?

[r3i]

Another factor to add into the mix is that WO have made incremental changes to the scope.  For example, the one that I have has tilt adjustments on the focuser which I believe were not present on the very first models and just recently, according to this thread on Cloudy Nights, they have lengthened the dew shield (there was quite a lot of comments and concerns that the dew shield was a bit on the short side).

[Davey-T]

There was some discussion of the short dew shield but I've not found it a problem, the dual mounted WO 110 FLT on the other hand dews up really easily with a longer shield.

Mine fits nicely in a Peli type case with camera, rings/dovetail,  and dew shield retracted, a longer dew shield would require removing the rings/dovetail.

Dave

[gnomus]

There was some discussion of the short dew shield but I've not found it a problem, the dual mounted WO 110 FLT on the other hand dews up really easily with a longer shield.

Mine fits nicely in a Peli type case with camera, rings/dovetail,  and dew shield retracted, a longer dew shield would require removing the rings/dovetail.

Dave

Do you have the WO or the TS version Dave?

[Davey-T]

Do you have the WO or the TS version Dave?

W Optics, super focuser with nice adjustment holds QS1683 solid as a rock.

Just in the middle of putting it in new foam

Dave

[Uranium235]

The WO also has a thermometer built into the focuser, which I think the TS does not. Its useful for checking when the scope has cooled to the ambient temp.

Also, (im not sure if the TS one does) the WO comes with an M48 - EOS adaptor.

[r3i]

There was some discussion of the short dew shield but I've not found it a problem, the dual mounted WO 110 FLT on the other hand dews up really easily with a longer shield.

Mine fits nicely in a Peli type case with camera, rings/dovetail,  and dew shield retracted, a longer dew shield would require removing the rings/dovetail.

Dave

I did have a bit of dewing up once with mine, but the dew on that night was really bad.  Since then I've always used a dew heater strap and have had no further bother.

[Ibbo!]

The WO also has a thermometer built into the focuser, which I think the TS does not. Its useful for checking when the scope has cooled to the ambient temp.

Also, (im not sure if the TS one does) the WO comes with an M48 - EOS adaptor.

That was it the thermomemter on the focuser

[ollypenrice]

That was it the thermomemter on the focuser

I think this was intended to help you focus by noting focal positions and temperature relationships but I reckon I'll let that idea glide past me...!!

Olly

[steppenwolf]

It's certainly a very attractive package and I have always held the view that a minimum of 5 elements are required to both colour correct and flatten a reasonable field. It is a great shame that the 'scope has been tarnished a fraction by some bad reports and I'd second Olly's 'use the right dealer' comment as this will be key if the worst should happen.

I have discussed the issue of similar looking instruments different badges in PM exchanges with Steve but it is a lottery really and much as I am a supporter of WO products (I have two telescopes and two reducer/flatteners made by them) I have no idea if they are at the top or middle of the pecking order with this production line but I have no doubt that there are 'layers' of QC in telescopes just as there are in many other products!

I have the temperature gauge on my little WO Megrez 72 and it is pretty but I wouldn't pay 'extra' for it.

Assuming that the focuser is as well made as that on the WO GTF 102 then it should be surprisingly good and Dave (DaveT) confirms this. Seeing Dave's QSI 683 mounted on the 'scope is making my wallet twitch as I love wide fields and my own QSI 683 would be such a good match.

[StuartJPP]

I must admit I keep looking at these refractors but I will hold out for as long as I can, the one thing that is really appealing is the focuser, much simpler than a lens...

It's certainly a very attractive package and I have always held the view that a minimum of 5 elements are required to both colour correct and flatten a reasonable field.

How does that theory extend to the 17 elements of my Canon 500mm f/4 L IS Lens (+5 if I use the 1.4x TC)

[steppenwolf]

How does that theory extend to the 17 elements of my Canon 500mm f/4 L IS Lens (+5 if I use the 1.4x TC)

Badly! :grin:

[davedownsouth]

W Optics, super focuser with nice adjustment holds QS1683 solid as a rock.

Just in the middle of putting it in new foam

Dave

WOS71.png

Very nice, do you know which Peli case that is?  Do you have the cat code?

[Davey-T]

Very nice, do you know which Peli case that is?  Do you have the cat code?

Not a genuine Pelicase, just a "cheap" Maplin copy, comes with block foam so had to buy new solid piece.

Dave

http://www.maplin.co.uk/p/large-high-impact-case-with-pre-cut-foam-interior-n14gr

[davedownsouth]

Cheers, cheap is good for me

[martin_h]

I have the TS version of this scope, obtained from Ian King. The focuser is fully adjustable and rotatable and holds a 7 position 2" filter wheel and cooled CCD with no problems.