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AT102EDL doublet v. AT115EDT triplet

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#1 bwhitton

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Posted Yesterday, 07:44 PM

Looking for opinions.

 

I've got an AT102EDL (F7) and case on order with Astronomics for $1225.  The scope is FCD-100/Lanthanum F/7 doublet with a guaranteed minimum Strehl of .95.
 

While poking around on the Astronomics site tonight (it's raining!) I came across the AT115EDT triplet (which includes a case) for about $175 more. It's an LD glass F/7 triplet.
 

I plan to use the scope for both visual and ap and was drawn to the 102 because of the glass and Strehl ratio.
 

Here’s my question: the triplet design basically eliminates chromatic aberration, right?  And with the 115 I'd get more aperture. Why wouldn’t I spend the extra money and buy the 115 triplet instead of the 102 doublet?

 

I've got an EQ6-R pro, so weight is not an issue either way.

Thanks for your thoughts!


Edited by bwhitton, Yesterday, 08:01 PM.


#2 photoracer18

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Posted Yesterday, 08:11 PM

All triplets are not totally color free. On that note they are generally better than doublets but not always specifically better. You have to look at the quality of the parts also. If you price out a telescopes parts what's left is the cost of the optics. And in the cost of the optics is the amount they spent in polishing time. The more time you spend the higher the Strehl ratio and the more they will cost. Everything else being equal. I can't tell you about those 2 scopes even though I used to own an AT115EDT. I never used it. It was owned by a person who lived out west close to my brother so I had the seller drop it off for him. Sent him a mount and some parts but he never got the chance to use it much so I resold it away from him a year or two later.

And from what I saw the difference is about $300 between those 2 scopes ($1095 vs. $1399).



#3 bwhitton

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Posted Yesterday, 08:58 PM

Thanks for the input.
 

The case is included in the $1399 AT115 price. The AT102 case is extra so $1225 for scope and case.


The triplet and larger aperture is what caught my eye about the 115.  But I really like the FCD-100 glass and .95 Strehl on the 102.
 

Too bad you can't take scopes out for a test drive!


Edited by bwhitton, Yesterday, 09:01 PM.


#4 Starlancer

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Posted Yesterday, 09:07 PM

I have been extremely happy with my AT115, there are examples of photography on my astrobin in my signature



#5 bwhitton

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Posted Yesterday, 09:22 PM

Fantastic images, Starlancer!

 

I ran some FOV simulations of both scopes and there is not a huge difference between the 102 and 115.  Would there be increased detail, contrast or something else?


Edited by bwhitton, Yesterday, 09:27 PM.


#6 Auburn80

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Posted Yesterday, 09:42 PM

Fantastic images, Starlancer!

 

I ran some FOV simulations of both scopes and there is not a huge difference between the 102 and 115.  Would there be increased detail, contrast or something else?

Based on your intentions, check to be sure a reducer/flattener is available for each. FAPP, I have both of those although my 4" is the Stellarvue Access 102 - FPL53/Lanth @ f7 and the AT115EDT. No AP though, just visual.




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