Astro-Physics 206mm for $100K USD

[Hans Tucker]

Interesting..Tony Hallas is selling his Astro-Physics 206mm (8") f/7.7 Refractor via Auction on Astromart. Opening bid starts at $48K USD
or you can buy it now for $100K USD...apparently it is only one of two ever made by Roland Christen. Looks like a real beauty and of recent vintage..2008.

[Bassnut]

Youde have to have rocks in yr head.

$78,700 buys you a CDK24" OTA (thats 24 inches!) AND an AP3600 mount with high precision encoders.

Please tell me an 8" refractor gives higher res than a 24" compound scope!, and is better value than a 24" WITH a seriously tricked up mount.

[jenchris]

The 8" is more of a grab and go though - LOL...
I can imagine that I could buy a used canvas from the Tate Gallery for 5 million and a brand new one from an art shop for 20 dollars .

I imagine the second hand one being really dirty too.

Horse for courses - but value is not really a good comparison.

[Kal]

Wishful thinking on the price I reckon.

With a quick search of previous auctions on Astromart, you can see that there have been three previous occasions when people have listed AP 206mm refractors.

The first listing was in 2005, it was serial #206EDF04, an F7.75 scope made in 1993 that was passed in at auction after getting a maximum bid of $37,676

Second listing is the same scope a couple of months later and it passed in at auction with a maximum bid of $23,600

Third listing was earlier this year with a 1995 manufactured scope serial #206EDF17, it passed in at auction as well at $36,101.

Also, going by the serial number, it appears as though AP made at least 17 of these 206mm F7.75 beasts

[Octane]

I'm looking at you, Greg Bradley. You know you want to. : P

H

[Waxing_Gibbous]

Who's Tony Hallas?

[asimov]

If I had that amount of money to play with astronomically, It wouldn't be spent on a refractor that's for sure.

[Kal]

an astrophotographer

http://www.astrophoto.com/

[Lester]

If I had that kind of money, it would be spent on a good "cloud filter" and a "steady seeing conditions machine".

ps, any left over would go for a deposit on anti sleep therapy.

[Geoff45]

Refractors are never about value for money. If you are one of those people who want an 8" refractor and you are rich, you indulge yourself and buy it.

Note added: Maybe he's taking your advice Fred and raising the dough to buy a 24" etc etc

[asimov]

Ok, I'll start building the first 2 straight away Lester. As with anything astro that is expensive, that'll be 20% up front though please sir. Cheque or money order is fine with me.

30K sounds like a nice round figure:thumbsup:

:P

[strongmanmike]

Res? res? sheesh it's all about res with you huh? :rolleyes: what about field of view man :eyepop:

1600mm fl = big beautiful field to fit lots in your shots = versitile yeh baby :thumbsup:

4800mm Fl = looking through a straw at a postage stamp :lol:

He he :P

I'd go the 24" on an El Capitain too though :whistle: ;)

[gregbradley]

:rofl: That's funny Humi!

The differences between APOs close together in aperture are not that great. Once you hit a high level of Strehl and accurate figuring and as long as it is a proven formula like oiled triplet then you are not going to get massive differences.

See these 2 test images. Same camera, same site, same conditions, AP140
TEC180. Both high quality, high strehl, oiled triplets, one fluorite (the TEC) one FPL53 (AP140):

http://www.pbase.com/gregbradley/image/115775756 TEC180
http://www.pbase.com/gregbradley/image/115775760 AP140

Do you see massive differences there apart from image scale?

Obviously the TEC180 will show more detail as it is larger. But stars, pinpoint sharpness to the corners of a large chip (Apogee U16M camera), lack of colour aberration seem the same to me.

How much better could an AP206 be over a TEC180 fluorite? It'd be better, but how much? Not a lot really in my opinion.

I see Tony Hallas uses a CDK17 now. Maybe he likes that better. It also has a reducer to make it F4.5 available so it is very versatile. It also is good for planetary and visual. As Fred says $100K buys a lot of high end gear.

There was an AP206 on Astromart recently that did not sell at US$45,000.
I think he is dreaming but you never know unless you ask.

I personally feel that the sweet spot for refractors is 155mm and my 180 is at the upper end of APO size for portability, performance, colorfree, large corrected image circle, high strehl etc etc. There was a TEC200mm fluorite recently for sale on Astromart for $36,000 that didn't sell. That would be very similar to the AP206 almost for sure. I don't know how much difference the coatings make - I am sure noticeable but the TEC has fluorite and if you've ever used one of the Tak fluorite scopes you'll know how nice fluorite is.

Having said all that it would still be an awesome scope and would be an amazing imaging machine as AP are simply the best bar none and the manufacturer all others are compared to. My AP140 is an amazingly perfect piece of optical and mechanical engineering with some incredible accessories like its unbelievably good reducer/corrector. What's not to love?


Greg.

[Octane]

I still think you need to add an AP206 to your war chest. : P

H

[strongmanmike]

Yep! I agree Humi :thumbsup:...com'on Greg :poke::poke::poke:

:lol:

[Geoff45]

No Mike
Fred doesn't go for what he calls "wide field rubbish". Postage stamp rules!

[Barrykgerdes]

And "narrow band" rules so chromatic aberation is not a real problem. Lots of captured light is what is required.

Barry

[Hans Tucker]

It get better people. An Alvan Clark Co 4 inch refractor with wood case has also come up on the Astromart auction...or buy now for $16K USD..you know you want it.:D .....1911 vintage

[Bassnut]

Res?, is there anything else that counts? (apart from the massive extra photons captured for a given time, duh). On the 17" with a 0.66 reducer (cant see one for the 24") the FL is 2270mm. Out of the oh-dear, another-soso-WW-done-that zone and short of the postage stamp size gear you bang on about :thumbsup:.

[strongmanmike]

Arhem, massive extra photons yes but from only a postage stamp size bit of sky :whistle:

Yeh the 17" + reducer would be a bit better...buuuut that wasn't what you suggested :D ;)

he he

[gregbradley]

I see noone had placed a bid for the AP206. A telling sign of the US economic state.

There was another for sale a month or so ago that didn't sell for US$45,000. Maybe the market is "saturated" with AP206 scopes!:lol:

Greg.

[Peter Ward]

Figure/strehl aspects of various scopes being equal, seeing gets you most nights.....

At sea level, larger aperture often simply means more data in less time.

The pro's don't site 10 metre class scopes at serious altitude because they like mountain air ;)

[Kal]

On a sidenote, that little 4" Alvin Clark refractor is going alright - 23 bids currently at $8100 with 11 days left

[rally]

Greg,

You said " . . . as AP are simply the best bar none and the manufacturer all others are compared to."

Was that a typo - didn't you mean ". . . bar one . . ." ;)

Looking at the colour correction of the Takahashi triplets - TOA series and the FSQ Petzval, compared to AP scopes, I think they have set the current bar height.
The image contrast is enhanced because these refractors can focus from IR to UV - a wider range of wavelengths and more accurately.

But I am not really wanting to get into the "this is better than that" argument, just to say that there are definitely more players than solely AP !

And as stated by PW the seeing, tracking, guiding and other errors are likely to be larger and more variable than the differences in chromatic aberration and as such not easily specifically measureable/detectable in the average amateurs images.

So the reality is for us mere mortals at sea level ! there are much bigger fish to fry than just OTA optical design and manufactured quality, but it is still good to eliminate what you can to reduce the total noise in the system.

Cheers

Rally

[strongmanmike]

Ah you know how it is Rally, us AP owners are like those American Mom's who put their little girls in those beauty pagaents...ours is our lill darlin no matter what and we cry and get angry if she don't win.

:lol:

[gregbradley]

Ah yes the fabulous Tak versus AP competition.

They are both wonderful scopes but having owned both I would have to give the edge to AP.

AP makes the incredible 155TCC corrector which is a reducer and flattener in one and corrected even for 16803 chips. I know Tak has a super reducer but I am not sure it has the same standard here.

AP focusers are superior to Tak ones. Tak is now playing catchup with its focusers as the number of complaints roll in about flexure with FSQ106ED's and heavy camera trains. It can't handle it without flex. I see a TOA150B with a heavier focuser to address this so they are handling it slowly.

FSQ106ED has no competitor really in the AP stable except for the 130 and its reducers. But that's a different price and availability and aperture. The FSQ106ED must be Taks biggest seller. I wonder why they don't bring out an FSQ130 or even an FSQ150. Now that would be unique and they could exploit their edge in Petsvals.

AP now has a Honders Riccardi astrograph which is unique and I suppose eventually the Mak astrograph Roland has made.

AP threads are infinitely superior to Tak ones which routiinely jam and are too fine/ too frictioned after their black coatings.

Having said all that I do love Tak scopes and have had several that I really like.

Of course the main advantage of Tak over AP is you can actually get a new one fairly easily!

I don't know that is true that Tak has the edge over AP on correction? You think? AP does .99 strehl on its optics. I doubt Tak does. Its lenses are made by subcontractors not by them.

Another aspect of AP scopes is the fact that Roland images himself. I have not seen images posted by Mr Takahashi - I have by Roland. This means he really knows what is needed and it shows in the attention to detail in his scopes. They are immensely practical and superbly thought out and engineered. For example the corrected illuminated circle from an AP155 or 140 with a flattener is around 100mm!!!! That provides a lot of future use when super large chips come out. They will still work when other scopes will vignette.

TOA series is an incredible imaging scope though. I have often been amazed at the resolution Marcus achieves with his TOA150. An amazing scope. Is AP155 a lot better? Probably not. You'd need a TEC180 to be better there hehehehe.:lol:

Greg.

[Hans Tucker]

I would think that the complex design (obtaining precise colour correction plus flat field) of the Petzvel would make a FSQ130 or FSQ150 cost prohibative. The largest Petzvel APO that I have come across was made by Televue and it was a 5.5" (140mm) and only a handful were made. Now Televue only offer the NP-101 & NP-127 in this design.

If I were to choose a AP refractor I would go with a AP-140..one day I'll own one..maybe I should place the order now given the long lead time.