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AP 130 F/6 EDF vs AP 130 GT

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#26 Markab

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Posted 24 August 2014 - 02:41 PM

It is funny to see that late-model Travelers with the FT in excellent condition are selling for the same price approximately as the 130EDF...but it seems reasonable as the Traveler hasn't been in production for a decade with approximately 700 made, and represents the only 4" scope Roland made, while the 5" EDT/EDF/GT keeps getting pumped out.



#27 orlyandico

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Posted 24 August 2014 - 11:35 PM

personally (and yes I must apologise for the sub-5K 130EDF assertion - lowest I've seen in review was 5.2k) anyone who buys a scope for the appreciation value is gonna lose.  We're not even talking inflation here. If I had put that EDF 5.2K in the market (say an S&P 500 ETF) in 2010, it would be 10k today.

 

No scope will ever give that return.  At best you're limiting your losses (because even if it appreciates the opportunity cost still outstrips the appreciation of the Uncle Rollo rarity-special).



#28 dr.who

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Posted 24 August 2014 - 11:45 PM

Sorry folks but this thread has gone pretty far off topic. Please going forward keep it on topic.



#29 jrbarnett

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Posted 28 August 2014 - 11:55 PM

"...but I have a method for figuring that produces great results, so that's the way we are presently making them - newest glass of high quality and hand figuring."

 

Hand figuring by the man himself. Now that is pretty cool.

Unless Roland is schizophrenic or the Queen, it sounds like A-P has more than one optician that does the hand figuring.  (The use of "we" rather than "I".)

 

This  to me sounds like they are aspherizing one or more of the surfaces because of the lack of availability of mating glass types that would allow a simpler all-spherical design.  It is pretty cool, if so.

 

- Jim



#30 JimP

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Posted 29 August 2014 - 08:48 AM

Yes you are correct M13,  Roland is the ONLY one at AP who hand figures the optics. Period.

 

JimP


Edited by JimP, 29 August 2014 - 08:48 AM.


#31 Scott99

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Posted 29 August 2014 - 10:24 AM

Yes you are correct M13,  Roland is the ONLY one at AP who hand figures the optics. Period.

 

JimP

 

the Hand of the Master!   it's like Shaolin Temple of refractors out there in Rockford!   :lol:  :lol:



#32 Derek Wong

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Posted 29 August 2014 - 11:08 AM

Here are two posts that are relevant to the discussion:

 

Link #1

 

Link #2

In this thread you need to scroll down to Uncarollo2's second post.  His first about 4-6" refractors is interesting...

 

Derek

 



#33 Paul G

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Posted 29 August 2014 - 02:57 PM

Here are two posts that are relevant to the discussion:

 

Link #1

 

Link #2

In this thread you need to scroll down to Uncarollo2's second post.  His first about 4-6" refractors is interesting...

 

Derek

 

Interesting to see a post by Todd Gross! Flashback!



#34 Markab

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Posted 29 August 2014 - 04:12 PM

 

Here are two posts that are relevant to the discussion:

 

Link #1

 

Link #2

In this thread you need to scroll down to Uncarollo2's second post.  His first about 4-6" refractors is interesting...

 

Derek

 

Interesting to see a post by Todd Gross! Flashback!

 

 

 

Whatever happened to Todd Gross, anyway? I liked his mini-reviews about AP, Tak, and just about everything else.



#35 The Ardent

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Posted 29 August 2014 - 04:33 PM

I bought or sold something from him earlier this year. Mentioned that I first read his reviews "last century" 



#36 Peter Natscher

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Posted 29 August 2014 - 05:02 PM

Here are two posts that are relevant to the discussion:

 

Link #1

 

Link #2

In this thread you need to scroll down to Uncarollo2's second post.  His first about 4-6" refractors is interesting...

 

Derek

So, reading what Roland says about his newer EDF's since the late 1990's, we observers are wasting our money on his fast APO's that are designed primarily for imaging. We should just buy a good slower refractor that will give us great results.  :smirk:



#37 madcity

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Posted 30 August 2014 - 02:48 AM

Yes you are correct M13,  Roland is the ONLY one at AP who hand figures the optics. Period.

 

JimP

 

In 2007/season 4/episode 10, the American TV series "John Ratzenberger's Made in America" had an episode that included a piece on AP and included a scene of Roland working on a lens cell. Nothing profound, but still quite interesting.

 

It's on youtube. See https://www.youtube....h?v=QX91KAAgFew


Edited by madcity, 30 August 2014 - 02:56 AM.


#38 Schubert

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Posted 30 August 2014 - 04:11 AM

Christen has stated on that Other Site the exact reasons.

N-ZKN7 glass used to be used as the mate for the center S-FPL53.

Schott and Ohara do make it presently, but the glass was and is problematic with striae and above all microbubbles causing scattering.

Not to mention availability in large sizes is sketchy at best.

CDGM makes K4A, the N-ZK7 equivalent, but it has the same problems on a bigger scale with even worse bubbling-problems.

 

Roland and other makers now use N-BK7.

This necessitates the aspherizing to bring in the blue/violet.

N-ZK7 did this of it´s own accord.

 

Airspacing and using a heavy crown like in the AP160 would also be a full-spherical solution. But this necessitates a heavier and thick lens-cell.....


Edited by Schubert, 30 August 2014 - 04:56 AM.


#39 Derek Wong

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Posted 30 August 2014 - 11:35 AM

 

 

 

 

Interesting to see a post by Todd Gross! Flashback!

 

 

 

Whatever happened to Todd Gross, anyway? I liked his mini-reviews about AP, Tak, and just about everything else.

 

 

I also refer to his reviews a lot.  I had an email conversation with him about a year ago.  He said he has been distracted for about 10 years and was working his way back into the hobby slowly.

 

Derek



#40 Derek Wong

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Posted 30 August 2014 - 11:40 AM

So, reading what Roland says about his newer EDF's since the late 1990's, we observers are wasting our money on his fast APO's that are designed primarily for imaging. We should just buy a good slower refractor that will give us great results.  :smirk:

 

 

Link #2

 

 

 

Basically yes, he agrees with many people on this forum.  The problem is that the slower high quality refractors don't sell as well and the few that are made are just as expensive as their faster counterparts.

 

Derek



#41 vahe

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Posted 30 August 2014 - 12:49 PM

 

So, reading what Roland says about his newer EDF's since the late 1990's, we observers are wasting our money on his fast APO's that are designed primarily for imaging. We should just buy a good slower refractor that will give us great results.  :smirk:

 

Basically yes, he agrees with many people on this forum.  The problem is that the slower high quality refractors don't sell as well and the few that are made are just as expensive as their faster counterparts.

Assuming that most of us are primarily after uncompromising performance when we dish out all that $$$$, first and foremost we need to decide, UPFRONT, what is more important to us, resale value or performance.
Once that decision is made, then you are ready hit the market.

 

Vahe



#42 Peter Natscher

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Posted 30 August 2014 - 08:52 PM

 

 

So, reading what Roland says about his newer EDF's since the late 1990's, we observers are wasting our money on his fast APO's that are designed primarily for imaging. We should just buy a good slower refractor that will give us great results.  :smirk:

 

Basically yes, he agrees with many people on this forum.  The problem is that the slower high quality refractors don't sell as well and the few that are made are just as expensive as their faster counterparts.

Assuming that most of us are primarily after uncompromising performance when we dish out all that $$$$, first and foremost we need to decide, UPFRONT, what is more important to us, resale value or performance.
Once that decision is made, then you are ready hit the market.

 

Vahe

 

As I get older past 64, resale potential becomes less important to me as the immediate performance my telescopes provide.  I figure I have 10 years + to continue my observing hobby as I have it presently.  After that, who knows?



#43 Scott99

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Posted 03 September 2014 - 01:19 PM

So, reading what Roland says about his newer EDF's since the late 1990's, we observers are wasting our money on his fast APO's that are designed primarily for imaging. We should just buy a good slower refractor that will give us great results.  :smirk:

 

 

 

Recently I met a member of my astro-club who is the original owner of a 1992 AP Star 155ED f/9.   These were aspherized doublets that had almost perfect color correction in the visual range. (better color correction than Tak's FS series).  I'm kicking myself for not getting the guy's email address, I would love to someday "downgrade" to this scope from my AP160.  This would be the ideal scope I would order today if possible.  An imager would be better off with the 160 and flatteners.

 

But RC has served us pretty well by making the 160 and 175 at f/7.5 and f/8.   Not much to complain about as a visual observer there.  The 160 gets you to 1200mm focal length, significantly more than the 155mm f/7's, and my old Clave Plossls work pretty well at f/7.5.  Not to mention the extra 5mm which is nice.


Edited by Scott99, 03 September 2014 - 01:21 PM.







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