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gregbradley
23-11-2008, 03:19 PM
I have had a few nice refractors and I thought I would put my view on them in writing as I used to love reading some of those ED Ting reviews of refractors and other scopes.

The refractors I have had are:

1. Orion ED80
2. Tak FS102
3. Tak FS152
4. Tak FSQ106N (fluorite)
5. William Optics 80mm APO triplet with the Lomo lens (erroneously marketed as a fluorite triplet)
6. Tak FSQ106ED with reducer
7. AstroPhysics 140mm with 4 inch focuser and matching telecompressor.
8. Astrotech 66mm ED
9. TMB 65mm Backpacker (several of these).

1. Orion ED80;
The Orion scope is a legend and extremely popular. Compared to an SCT it gave fabulously sharp views although with only 80mm these would be limited to widefield star views not DSO's so much except for the brightest.

It is very lightweight and this makes it handy for piggybacking on an SCT or other scope. Some have had trouble with the focuser and collimation, mine was fine. That was a long time ago and there are so many variations on this scope now I don't know which is which. Different brands no doubt use the same lens but their own touches. If I were to get another one I'd check out Astrotech, Stellarvue or similar for their version.

Because it was lightweight I also used it a large telephoto lens for some terrestial photos. I'd give it about 7 out of 10 as the quality assurance is not really there and the machining and assembly was a bit basic although practical and workable.

2. Tak FS102:

This was my first Tak and the sheer quality and strength of construction is the first thing that hits you. Tak oozes quality construction.
The scope was flawless and only showed a small amount of edge colour on the moon otherwise it showed none visually.

102mm again, is quite dim for viewing DSOs but is great for widefield views of star fields. I remember a spectacular view through this scope using a Binoviewer (Denk) and a pair of 19mm Panoptics.

3. Tak FS152:

I agonised over this choice for a long time as the TOA series had just been released but only the TOA130. They were similar prices but in the end I decided aperture rules and to go with the most aperture.

The scope again oozes luxury and quality. That huge big green fluorite objective is very appealing.

First light was taking out to dark skies near Cowra NSW. Looking around with a large number of high end eyepieces I had at the time was stunning.
Up to that time I had used a Meade LX90 (8 inch SCT). I was stunned that the FS152 was brighter than this 8 inch SCT and the views were so sharp and detailed it was really something. It was particuarly sensational with a 22mm Nagler type 4. A stunning scope, lightweight, easy to use, virtually no cooldown time, fabulous focuser. Everything worked beautifully.

For imaging it was also great although the doublet starts to show its limitations with a tendency to have blue halos around brighter stars. This is blue being out of focus as APO manufacturers try to get green in focus and blue least. Still overall a stunner.
I upgraded mine later to a 4 inch focuser and dedicated field flattener. This enabled the scope to handle any chip up to 16803 and perhaps a bit beyond. The Tak microfocuser which was an add-on was good but a bit spongy. Not as good as others I have used since.

9 out of 10.

4. Tak FSQ106N;

This scope was close to perfection. For imaging it was unrivalled in its time as hundreds of incredible images prove.
The 4 inch focuser and camera rotator and lock were just a pleasure to use. Quite a heavy scope for its size, tanklike is the usual expression describing it. Loved it. Minor optical aberration in FSQ106Ns where bright stars at the edges of the image have a dark tunnel through them. Easily removed with Photoshop but was told it was vignetting. Not just my FSQ but all of them. 9.5 out of 10 for this scope.

5. William Optics 80mm Lomo triplet;

This scope was a disappointment. After reading all the hype about super apo and the false advertising claiming it was a fluorite triplet (WO have never made a fluorite scope and lie about this - they call ED glass fluorite much like Meade called their RCX advanced Ritchey Chretien).

It arrived badly out of collimation. I had to install a metal shim in the rotatable focuser to improve it which it did enormously. The visual back was tad oversized so things tend to be able to pivot (poor machining). The focuser lock did nothing practically. The scope looked nice and the tube was nice but overall a 4 out of 10 for lying about the lens, the really poor collimation, the oversized sloppy visual back and the useless focuser lock which slipped. After the quality of the Taks this was an eye opener as this was an expensive scope.

6. Tak FSQ106EDX and reducer.

I almost didn't buy one of these as I was so happy with my FSQ106N. I also didn't like the look of the initial images that were being posted on the net using these scopes. They seemed sharp yes, but the colour seemed harsh and a bit greenish. The earlier FSQ gives more colourful images, the newer FSQ gives sharper images.

As a scope everything works very well. The captains wheel rotatable focuser system is probably a waste of time and Tak should not have bothered as I think most people keep theirs locked down.

The microfocuser is absolutely superb and even better than the Feathertouch one on my AP which is fabulous.
The focuser lock though is not as good and if you fine focus and then lock it shifts the focus a touch. So you have to keep the focus lock partially engaged and then tighten it once focus is spot on.

The dewshield slides better than the FSQ106N which was a little sticky. The scope is more compact and super well made.

The F3.64 reducer is an optical marvel and will handle cameras as large as the Apogee U16M. I am not aware of any other scope that has a reducer that handles large chips. They typically cause coma and you are stuck to using a flattener and no reducer. The only other one is the AP 155TCC. That costs US$2,300 or so. So I give the reducer a 10 out of 10 and the scope a 9 out of 10 with the focuser lock and the captains wheel setup the only minor criticisms on an otherwise near perfect scope. Importantly, the optics are perfect.

7. AstroPhysics 140mm with 4 inch focuser and 155TCC:

Believe it or not I bought this scope on a whim! I had already ordered a TEC180mm fluorite triplet and knew it was going to take a while. But after reading all the praise for AP scopes over the years and having seen the absolute best images from these scopes I thought it was a rare chance to get one. One was for sale on Astromart that was only 3 months old and had the telecompressor which is a work of optical art.

First impressions of the scope were stunning. This is super quality. You can see the years of experience Roland has in developing his scopes to being the most practical, useful, built for purpose scopes around. Even compared to the super high quality of the Taks I'd have to give the nod to the AP. It is another step up.

A largish scope, heavier than I expected with a huge beautiful greaseless 4 inch focuser that has a coppery golden gleam to it. The feathertouch microfocuser is fabulous. The focuser lock works well, the machined compression ring system is very secure and solid. Everything about the scope is very solid and well made. The heart of the scope though is the lens. A Roland Christan FPL53 ED triplet with the correct matching glass lens made to his exacting standards and hand figured by him personally. He has super high standards.

I was also impressed by the rings and dovetail plates etc. All really practical and super well made.

First views through this scope were equally impressive. It is F7.5 and around 900mm focal length (from memory). So it gave a wider view than the FS152. I was stunned at how small and pinpoint stars looked. The Tak FS scopes are super sharp, this was in another league. Tiny pinpionts, the Jewel Box was super super sharp.

Also for imaging this scope really shows its stuff. A huge 100mm illuminated field, the huge focuser and luckily I was able to attach my Tak FS152 dedicated flattener which worked perfectly giving pinpoint stars to the corner of an STL11 or Apogee U16M camera. No hint of false colour at all. All stars show their natural colour and no blue halos.

This scope is a 10 out of 10 and you realise why Roland's scopes are so sought after.

8. Astrotech 66mm ED. I use this little scope for a guide scope and admire how well made it is for the money. It was the cheapest scope I have bought and it really is incredibly well made. It does a very good job as a guide scope.

9. I bought a few TMB 65mm ED Backpackers from Burgess Optical as they were going for US$20 without a focuser. I since have bought a couple of focusers for about $30 each. I gave some away as gifts. I now have a couple with focusers and it seems to be a nice little scope but the Astrotech 66mm ED is much higher quality.

There's my experience so far with refractors. I hope you find it helpful.

Greg.

Miaplacidus
23-11-2008, 04:08 PM
Well, I'm not sure about useful. But entertaining, enjoyable — definitely.

Thanx,

Brian.

AlexN
23-11-2008, 04:53 PM
Im sure it will be useful to anyone looking to buy a refractor in the future...

I must say, it does point out one obvious factor. You get what you pay for.

Bassnut
23-11-2008, 04:57 PM
Very enlightening Greg, a great read.

GeoffW1
23-11-2008, 06:40 PM
Hi,

Thanks for this, very interesting as I am making long-range plans for a good-quality refractor, and these particular comparisons are quite relevant.

Cheers

MrB
24-11-2008, 02:22 AM
^ +1

Omaroo
24-11-2008, 07:29 AM
LOL! I'm at #2, with a #6 in my plan, but it just goes to show how thin the air is up there in top quality refractor land when you start on Astro Physics gear. One day.... one day..:doh:

DJDD
24-11-2008, 08:25 AM
I am just at a variant of #1 and i can see an expensive path ahead.:lol:

thanks (for the article not for making me think about a life of crime!) :lol:

gregbradley
24-11-2008, 01:09 PM
Its an interesting choice isn't it? Obviously its cost vs what you want to achieve. And yes these scopes are very expensive with most having US dollar price tags.

When you consider the costs of losing when reselling then there is a case for saving up and getting a really good scope once and using the hell out of it.

Another point I should have mentioned.

The Tak scopes etc are very liquid in the sense that they will resell quickly and for a good price. Lower end scopes devalue much harder and you will lose more on resale. So you can use a high end scope like an FSQ for a few years and sell it and you will only lose a few hundred dollars which you could consider "rental".

In fact one strategy if you can plan it out and have the patience - is to buy an expensive scope when our dollar is strong and then later if you tire of it you can sell it for a profit if our dollar goes down again (pretty reliable that it will at some point).

Greg.

netwolf
24-11-2008, 03:25 PM
Greg, great review. Could you please provide more details about the Lomo Triplet model. I recently got a WO Megrez EDII 80 triplet, its not the Lomo one. I have not had a chance to test it yet, weather is not co-operating when i have time.

gregbradley
25-11-2008, 05:10 PM
The Lomo lens itself was probably great. Although I doubt the marketing term of super APO applied. Super APO means 4 colour lines cross meaning at a point 4 colours will be infocus. APO means 3 colours in focus - Roland Christen has written this up at various times and there are symbols they use to depict various colours but from memory it was green, blue and I think red. Often in "APO"s it is only green and red and blue is off - hence the violet halos. With Achromats I believe green is usually in focus (as green is more present in eyesight) and red and blue would be out of focus hence the violet and reddish/yellow fringes.

It was the rotatable focuser which apparently was either mounted onto the tube not in a square fashion or the machining of the rotatable focuser was off so that it was out of square to the tube. I attached a red laser to the eyepiece holder and rotated it. I held a ruler over the dewshield to locate where centre of the lens should be - it was about 15-20mm off which is a huge error. Visually I was seeing seagull type stars off from the centre of the field. This wasn't what I was expecting from a "Super APO" best lens in its class scope.

I was told by another person who had the same scope he had a similar problem.

So it probably was the William Optics tube and focuser at fault.

This same lens is fitted in others tubes like Stellarvue, TMB/APM.

I'd go the APM version if I got another one.

Once I corrected the poor collimation it became very sharp and colour free and that was with the collimation still of by about 5 or 6mm.

So an APM version with a feathertouch would be the go but again it costs more but not that much. The focuser was OK but not great. It slipped under load, was machined slightly too large with poor consequences, only had 2 tightening screws when it needed 3 and the focuser itself would slip when trying to focus and you had a bit of weight in it. A long way from a Tak.

This was about 2 years ago now and I may have simply gotten a bum one. These are made by Pern Long who now sells to anyone not just William Optics.

Greg.

gbeal
25-11-2008, 05:42 PM
I have a Lomo/TMB 80/480 triplet (well that is what it says on the outside), and it is a stunner. It was for sale a while ago here, and I considered it the steal of the century.
Mine now has a Feather Touch, as the stock focuser while OK, wasn't as good as the FT. They sell for damn good money on Astromart used, and the new price from the likes of Teton is astronomical.
Nope, I'll never get shot of it, LOL.
Gary

AlexN
25-11-2008, 05:46 PM
I saw the TMB 80/480 for sale here, and messaged about it but was too late!!! Now I know who to blame!! :P :D

I bet its a real ripper!

Rigel003
25-11-2008, 06:44 PM
Thanks for the report, Greg. I'd love to upgrade my Tak to something larger in the future so this is interesting reading. An AP would be nice but don't think I'll have much chance despite over 7 years old the waiting list. Did you buy the FS-152 2nd hand?

GrahamL
25-11-2008, 06:52 PM
Refractorman :thumbsup:... Are you on the wait list for any other a/p scopes ?



Love it :) :)

anj026
26-11-2008, 08:39 AM
Thanks for sharing your experiences Greg :thumbsup:

gregbradley
26-11-2008, 04:59 PM
Yeah that'd be the one to have.

I bet it is beautiful.

Greg.

gregbradley
26-11-2008, 05:02 PM
No I got the FS152 new. This was about 2.5 years ago when Tak was still making them.

Tak has its lenses made by Optron a company owned by Canon. Optron still makes some fluorite lenses apparently. TEC makes a fluorite lens and so does Stellarvue. They use Schott Glass from Germany as their supplier.

I visited the TEC factory in Golden Colorado in March. Golden is really a suburb of Denver - a bit like Penrith is to Sydney. Yuri showed me the fluorite blanks. About 1 inch thick and a big milky disc. They grind and polish the discs with a computerised polishing machine.

Greg.

gregbradley
26-11-2008, 05:09 PM
I have been on the wait list for an AP160 for about 3 years now. I haven't heard of anyone receiving one in the recent past. I think Roland concentrates on a particular model for a while.

AP really don't have a wait list anymore for their mounts and could be considered to really be a mount manufacturer more than a refractor manufacturer. But Roland has posted that he does about 200 scopes a year which is nothing to sneeze at. But he does runs of particular models. He did a run of about 100 I think he said of AP140s when they were first released about a year ago.

He recently released the 130mm F6 Gran Turismo compact APO.

There are a few AP160mm around but not very many. The 155EDF is the one that comes up occassionally (one just sold on Astromart for US$9000 and I think it had a 2.7 inch focuser which would have to be replaced with a 4 inch to be ideal for imaging).

TEC is more accessible and is really the same type of scope to much the same standard. Yuri and Roland seem to be friends and Roland respects Yuri's work so that is high praise.

So if you don't want to wait get yourself a TEC. Anacortes was recently promoting they could ship 160mm or 180mm in Jan. I hope they are not selling my one! (I better call Yuri again).

A TEC160ED or even better a TEC160 fluorite would be a dream scope and no doubt matches the AP blow for blow or the differences would be minor indeed. TEC has ardent fans much like AP does.

Having said that I have not seen TEC140 images around that are as good as AP155 images. Not sure why. Perhaps the AP155 has a bit more focal length or perhaps Roland has added his own expertise to make his scopes just that more perfect for imaging as he is an imager himself.

Greg.

Rigel003
26-11-2008, 05:56 PM
I've been reading up on these of late.The last people to receive AP 160 EDFs were on the waiting list from 1999. (I've been there since 2001). However, there have been no production runs at all of the 160s since 2005 - only the 130 and 140. TECs have very high praise but are said to be optimised as visual instruments. There are quite a few photos on the web taken by the TEC 140 which is apparently not quite colour free. There are very few around from the larger TECs but I've also been disappointed with the images I've seen. In particular there seems to be quite a bloom around bright stars.

gregbradley
26-11-2008, 09:54 PM
Hi,

Interesting data about the wait list.

The TEC range is completely free. I have never read anyone who has one say otherwise. They are almost identical to the AP 155/140/130 line - FPL53 oiled triplets. I am sure you would find former AP owners who would swear their TEC was as good if not better than their AP. And vice versa. At this high level of quality it can become personal preference. Also Tak owners would also say theirs is just as good and I am sure TMB/APM owners would also assert their scopes are the best. It seems to me the differences at the high level are far less. A bit like Ferrari versus Porshe or BMW versus Mercedes.

I am not sure blooms around bright stars comes from the scope. That would be the camera, filters. Any scope will show a bloom around bright stars. That is the camera overexposing. Some scopes minimise it more than others and I'd say that is more a function of baffling and possibly light scatter. Some cameras show a bloom more than others (ST10 has microlensing artifacts).

I have seen some impressive TEC160 fluorite images. The 140 users seem to be mostly visual as you mention but there are plenty of examples. Johannes Schedler has some nice images with a 140.

Here is an example of Eta Carina with a TEC 200mm fluorite triplet (no longer made). To me this is the best image of Eta Carina by anyone.

Greg.