Jump to content

1912116577_Solarchallenge2022banner.jpg.913a200cf105ddeae9f37765cb1d0c73.jpg

FS60Q vs Zeiss Telementor


Recommended Posts

This is just a teaser really. I mentioned in another thread that I wanted to compare these two scopes when I get the chance ie a 60mm f10 Fluorite apo vs 63mm f13.3 Zeiss Achro.

I’m fully expecting the Tak to win this one but it will be interesting nonetheless. Colour correction will certainly be much better on the Tak, but targets such as doubles will likely be a closer comparison.

I’ve set the scopes up on my Giro-WR mount on the Gitzo so it’s ready to go as a grab and go setup. Just need some of those rare clear skies to give it a go.

1C4B1B39-E4D0-4ACB-A572-DDB63D42E61B.jpeg

BA70DD69-1437-4D78-BFB6-512F7BCB7070.jpeg

116FAEEB-ABE0-45C9-99CC-9538FC7528D5.jpeg

  • Like 9
Link to comment
Share on other sites

Presumably the FS-60Q is the same scope as your FC-76DCU(Q) but with the FC-76 objective unit replaced with the FC-60CB objective unit ?

Look forward to your comparison reports against this lovely Zeiss.... at f/13.5 even as an achromatic it could compare very well against the (slightly) shorter focal length apochromatic 🤔

 

 

Edited by HollyHound
  • Like 2
Link to comment
Share on other sites

47 minutes ago, vineyard said:

On a pound-for-pound basis, my money's on the Zeiss.

Probably true! The Telementor cost me £200! Hard to quantify the differences though. I suspect the Telementor will show most of not all that the Tak does, it will come down to the aesthetics of the view in terms of CA I should think.

  • Like 2
Link to comment
Share on other sites

1 hour ago, HollyHound said:

Presumably the FS-60Q is the same scope as your FC-76DCU(Q) but with the FC-76 objective unit replaced with the FC-60CB objective unit ?

Look forward to your comparison reports against this lovely Zeiss.... at f/13.5 even as an achromatic it could compare very well against the (slightly) shorter focal length apochromatic 🤔

 

 

Yea, exactly that. It’s amazing how much shorter the 60mm is. Can try the CB too to make it a bit fairer.

  • Thanks 1
Link to comment
Share on other sites

Just now, Mr Spock said:

I had a look through a Telementor a few years ago. I found it 'colourful' 😜

They definitely are Michael, despite their excellent reputation. Viewing the Moon is pretty good, and doubles but they are certainly not colour free by a long way in my experience.

  • Like 1
Link to comment
Share on other sites

Interesting that the 63mm F/13.5 should show noticeable false colour. According to that chart that we post quite a bit an achromat of that spec should be practically colour free :icon_scratch:

It's probably very nicely figured and polished though.

  • Like 2
Link to comment
Share on other sites

14 minutes ago, Mr Spock said:

It was nice and sharp for 60mm, but for a long focal length I found it a bit disappointing. From memory my '70s Prinz 550 was much better controlled. Though that was f15.

I do see mention from some people that colour is well controlled, but it is not what I experience. As I recall it is mainly in the blue end so perhaps people who are less sensitive to this don’t see it?

Link to comment
Share on other sites

Well, that was unexpected in a number of ways. Firstly I had no expectation of doing any kind of observing as I was expecting cloud! Secondly at 10.30pm when I looked out to lovely clear skies, the Moon and Orion I doubted I would be bothered to put a scope out. Lastly I was quite surprised by the results I got when I did!

Having set the FS60Q and Telementor up on the Giro-WR/Gitzo upstairs in my office, I managed to carry the whole lot downstairs and out into the garden, with an eyepiece case in one go! Now that’s grab and go with two scopes!

I didn’t really give them much chance to acclimatise before starting, but was out for around an hour and a half so they had plenty of time while I was observing, and after the first ten mins or so I didn’t really see any change.

Kit wise, I used a Baader Zeiss T2 prism in the Telementor and a Baader BBHS mirror in the Q. Seemed fairer to give the prism to the slowest scope.

To try to keep the mags similar, I used either an 18mm and 12.5mm pairing giving x46.7/1.3mm exit pupil in the Telementor and x48.3/1.2mm exit pupil in the Q, or a 9mm and 7mm giving x93.3/0.7mm and x86.2/0.7mm respectively. So, not exactly the same but hopefully close enough to allow meaning comparisons.

The mount was a little grabby, I assume because it was quite unbalanced due to the lightweight Tak trying to compete weight-wise with the tank barrel Telementor! It was useable though, so I stuck with it. The AZ75 would have been far better.

Moon first, looking fab naked eye and stunning through the scopes. I used the Telementor first, at the lower power and was spellbound for quite a while, thinking it can’t really get any better than this. Having agreed that it is ‘colourful’ earlier in the thread, it looked anything but colourful now. No visible CA so long as eye placement was correct, and beautiful renditions of the lunar surface, with different shades and colours. Standouts for me were the Apennine Mountains, Rupus Recta and just the terminator in general. Switching to the Tak the view looked slightly less bright, and a shade cooler or cleaner if that makes sense. I don’t think I preferred either view, they were both highly engaging and ones that I could look at for hours.

Switching to higher power in both scopes and things began to change. On the Telementor, the CA became apparent, but not everywhere. Along the terminator it seemed very well controlled, barely present, but towards the limb by Clavius and Tycho, where it was brighter perhaps, it was awash with a blue haze. That’s not to say the view was bad, but the CA was definitely there.

In the Q, CA just wasn’t a factor, I couldn’t see any. A lovely clean and clear view, still slightly dimmer than the Zeiss. Again the view felt cleaner, a little more clinical if you like, cooler than the Telementor and likely a truer representation of the lunar colours.

I then spent ages comparing very fine detail along the terminator to see if I could see more in one than the other. The surprise was that if anything I could see a fraction more detail in the Telementor. I guess there is a 5% increase in aperture giving slightly more resolution and brightness which may explain it, and also the Telementor was operating at slightly higher mag which will also have helped. I will try again another night and give the Tak the mag advantage and see whether it can utilise that in the same way, but last night there was just that little bit more structure visible in the Telementor, and some of the threshold peaks and crater rims right on or over the terminator were easier to see.

Moving on the Rigel, I found the Tak to hold the advantage here. The primary was cleaner as you would expect, though still showing some atmospheric CA. The secondary was easier to pick out, still relatively close in but quite clear. In the Telementor, the primary showed quite a bit more CA and was just that bit more flary as a result, and whilst I could still see the secondary it was a little harder, and came and went with the seeing.

M42 was pretty similar between the two, although the Telementor’s brightness showed up here and one or two tiny threshold stars in the nebulosity were easier to see. Could be a mag thing, but felt more to do with brightness, again perhaps aperture?

Finally I tried Castor. In the Tak they presented as beautiful, hard white uneven bullseyes on black, with a clean diffraction ring. Clear separation and a really nice view. The Telementor presented a more yellow view in comparison and with a little CA surrounding the stars, but otherwise the optical quality was similar in terms of airy disks and diffraction rings. Clear separation albeit filled with a little CA.

I’m attached some images and crops which may illustrate the points. The Telementor is first in each pair, as you can likely tell from the CA. These were the best of four or five images in each case, so will still be subject to seeing variations but are fairly representative I think. The CA showing on the Tak images was not visible visually, and the Telementor did show just that bit extra in terms of  brightness and detail, possibly aperture related or due to magnification differences. It does show that the old girl (Telementor) is still very capable and has excellent optical characteristics, CA aside. Not bad for £200!

More to follow 👍

Just to add that the images are totally unprocessed, just as they came out with similar setting between the two.

A862673C-6A14-4D4E-AF61-072652F701B9.jpeg

DF15DCBE-F169-4BC0-BEE2-D9C1391D3241.jpeg

C575C23D-918A-4F55-B620-1BD0F01C94FB.jpeg

E664D8ED-8E31-4D5D-99F2-AC74AD080CDE.png

6879A220-8128-4AF6-9212-C6FCD1FAA641.png

22986468-ABF4-4864-A62A-FACD927978D2.png

6538B026-63EA-4CF1-84BF-489CF0FEEDB1.png

  • Like 8
  • Thanks 1
Link to comment
Share on other sites

Nice report @Stu & yes a lovely setup.  I'm v much taken w my Telementor - a lovely scope.

On the CA, what EPs were you using?  I did a comparison with an old Vixen 6-O (0.965") and a Nag zoom at 6mm in my TM a while back (after getting a lovely V 6-O from another SGLer).  I did notice more blue flare with the V 6-O than w the Nag (but equally it felt like I noticed more detail w the V 6-O which I wasn't sure might be psychological: with a more restricted FOV than the Nag maybe I was concentrating more)?

Anyway, that difference in blue flare then reminded me that I can't recall noticing blue flare when I use CZJ 0.965" orthos w the TM.  I will double-check that again tonight (I was doing a quick lunar session a coupe days back & expecting blue flare when I put in the CZJ 10-O & I didn't notice any).  I may be mis-remembering but I think I once read that the CZJ ortho EPs were designed to work w the TM to offset any residual CA so that the combination of the two gave a colour-free image.  Does that sound right?  I can't for the life of me remember where I read that though (I know its the case w some types of CZ microscope EPs where those are designed to correct for specific objectives?).

Will double check the colour w a 10-O tonight (sadly no CZJ 6-O in the armoury :) ).

Nice report - yes the difference in price is such that I could never justify it (maybe an FOA-60Q though 😂...)

  • Like 3
Link to comment
Share on other sites

Nice report Stu! Your findings confirm mine when it comes to the 60Q. I am very bothered by CA and was very worried about it in a fluorite doublet. I was very pleasantly surprised at how well the 60Q does.   

  • Like 1
Link to comment
Share on other sites

3 hours ago, vineyard said:

Nice report @Stu & yes a lovely setup.  I'm v much taken w my Telementor - a lovely scope.

On the CA, what EPs were you using?  I did a comparison with an old Vixen 6-O (0.965") and a Nag zoom at 6mm in my TM a while back (after getting a lovely V 6-O from another SGLer).  I did notice more blue flare with the V 6-O than w the Nag (but equally it felt like I noticed more detail w the V 6-O which I wasn't sure might be psychological: with a more restricted FOV than the Nag maybe I was concentrating more)?

Anyway, that difference in blue flare then reminded me that I can't recall noticing blue flare when I use CZJ 0.965" orthos w the TM.  I will double-check that again tonight (I was doing a quick lunar session a coupe days back & expecting blue flare when I put in the CZJ 10-O & I didn't notice any).  I may be mis-remembering but I think I once read that the CZJ ortho EPs were designed to work w the TM to offset any residual CA so that the combination of the two gave a colour-free image.  Does that sound right?  I can't for the life of me remember where I read that though (I know its the case w some types of CZ microscope EPs where those are designed to correct for specific objectives?).

Will double check the colour w a 10-O tonight (sadly no CZJ 6-O in the armoury :) ).

Nice report - yes the difference in price is such that I could never justify it (maybe an FOA-60Q though 😂...)

I don’t know for sure, but guess it’s quite possible for an eyepiece to be optimised to compensate for a specific scope’s characteristics.

I was using Baader Genuine Orthos to try to keep things as even as possible, trying to match the mags and using the same eyepiece type in each.

Like you, I do enjoy the Telementor, fun to use, some historical interest to it, built like a tank and very enjoyable views, particularly of the Moon.

 

  • Like 1
Link to comment
Share on other sites

A great read Stu, with some great "bits of bait" laid out for us to pick up!😂.

Ok, I'll have a nibble. A few thoughts:

- I personally much prefer the look of the Telementor..no disrespect to the baby Tak, but just as nowadays I prefer grown up adults to small children, I also prefer my Taks "grown up"🤭😂..

- From your photos, the Tak clearly wins on CA, and the Telementor clearly wins on detail seen- as you say, it could be due to the extra 3mm aperture!

- from a grab and go perspective, the Tak clearly wins, far more easy and practical to take on holiday, on planes etc.

- "Bang for Buck" value for money..an easy win for the Zeiss. A Zeiss scope for £200 is by any measure a snip!

Finally, when you think that the Telementor was designed and marketed originally as a "School Telescope", and sold in communist East Germany and beyond in thousands, it's just remarkable that even now 45-50 years on, it acquits itself so well against the best modern technology has to offer.

Full respect to El Telementor!👍

Dave (F13.3Rules)😋😊

 

  • Like 3
Link to comment
Share on other sites

18 minutes ago, F15Rules said:

A great read Stu, with some great "bits of bait" laid out for us to pick up!😂.

Ok, I'll have a nibble. A few thoughts:

- I personally much prefer the look of the Telementor..no disrespect to the baby Tak, but just as nowadays I prefer grown up adults to small children, I also prefer my Taks "grown up"🤭😂..

- From your photos, the Tak clearly wins on CA, and the Telementor clearly wins on detail seen- as you say, it could be due to the extra 3mm aperture!

- from a grab and go perspective, the Tak clearly wins, far more easy and practical to take on holiday, on planes etc.

- "Bang for Buck" value for money..an easy win for the Zeiss. A Zeiss scope for £200 is by any measure a snip!

Finally, when you think that the Telementor was designed and marketed originally as a "School Telescope", and sold in communist East Germany and beyond in thousands, it's just remarkable that even now 45-50 years on, it acquits itself so well against the best modern technology has to offer.

Full respect to El Telementor!👍

Dave (F13.3Rules)😋😊

 

Dave. I’m really not sure our friendship can survive you saying you don’t like my baby. You’ll be saying he’s ugly next!

🤣🤣🤣

I do agree though, the Telementor looks excellent, a proper scope, and very robust, just pretty hopeless for taking around with you.

I am a bit mystified actually by such a difference in brightness, despite the higher power. Can it be the aperture difference? I know from playing around with lots of these little scopes that seemingly small differences are quite big in percentage terms so do make a difference. It will be interesting to see if more mag on the Q allows for more detail but I suspect perhaps not.

You are right about the Telementor being amazing for the price, and for its age. It’s still a very competent scope with plenty to offer. I made the mistake of selling my first, but won’t do that again! A bit like the Genesis and FL102S! When will I learn? 🤣

  • Like 4
Link to comment
Share on other sites

1 minute ago, mikeDnight said:

I wonder if prism vs mirror played a part in perceived brightness?

Yes, always a possibility when not using identical kit in each one. I’ll switch them around next time.

  • Like 1
Link to comment
Share on other sites

Great write up Stu, the photo's demonstrate your writing very well. 

I am tempted to point my Skylight at the moon and compare to your telescopes. If I use a 20mm eyepiece I get 1.2mm exit pupil, and if I use a 12mm eyepiece I'd get 0.71mm exit pupil. Hmm the gauntlet has been thrown down ! 🙂

  • Like 1
  • Thanks 1
Link to comment
Share on other sites

2 minutes ago, Dave1 said:

Great write up Stu, the photo's demonstrate your writing very well. 

I am tempted to point my Skylight at the moon and compare to your telescopes. If I use a 20mm eyepiece I get 1.2mm exit pupil, and if I use a 12mm eyepiece I'd get 0.71mm exit pupil. Hmm the gauntlet has been thrown down ! 🙂

Thanks Dave. Sounds like a plan 👍

Obviously the visual views are sharper than my ropey old smartphone shots but they do illustrate the points as you say. I just noticed actually that the first close up Telementor pic even shows how the CA is more noticeable on the bright areas and the limb than on the dimmer terminator.

Link to comment
Share on other sites

20 minutes ago, mikeDnight said:

I wonder if prism vs mirror played a part in perceived brightness?

Interesting Mike.. last night I used my 2" dielectric diagonal Cyclops with some large 2" eyepieces for the first half of the session.

Looking at M42 with the dielectric and an excellent 23mm Axiom LX eyepiece, I could look to the North East of the Trapezium (right way up reversed diagonal view) and see the two faint stars immersed there in the nebula..the "right hand side" star was visible with direct vision, the left hand side star was visible only with averted vision.

Half an hour later, I switched to my Revelation binoviewer in a Baader Zeiss BBHS T2 prism and a pair of Kson 16.8mm orthos, and was very surprised to see both these stars, very clearly, with direct vision!

To be fair, I was using a higher magnification with the bv, which made the contrasting sky background darker, but set against that, the binoviewer is usually held to lose around 0.5 to 1.0 order of magnitude due to the light beam splitting..so, I tend to think that the BBHS prism was reducing light scatter and possibly having better transmission than my dielectric diagonal? I believe the Baader website claims 98% transmission for the BBHS T2 prism..I don't know what the claimed transmission of my Astro Tech diagonal is though..:glasses12:

Dave

 

Edited by F15Rules
Typo
  • Like 1
Link to comment
Share on other sites

Very enjoyable read @Stu, and all the other comments too.

I've just watched Masterchef final and found it very tense. But nothing compared to Tak vs Telementor :)

I must admit to rooting for the baby Tak the whole way through :)

Malcolm

  • Like 1
  • Haha 1
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.