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1st refractor

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#1 svsalako


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Posted 17 January 2020 - 07:53 AM

Hi All --


I am looking at buying my first refractor. It will be used 50/50 for visual and beginning astro photography. I am looking at the ES ED102 Essential series triplet, which is on sale at the moment. However, I have seen many folks also recommending the Astro Tech 102 ED doublet. The AT is less expensive, although you need to also buy a diagonal for an additional $120  for a total of $720 to be a fair comparison. The ES is on sale for $959, and they also have a package deal with their EXOS 2 mount. On paper the ES seems to be the better choice, but sales descriptions can be misleading, so I am soliciting thoughts and advice before pulling the trigger.


Thanks in advance.

#2 SeattleScott


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Posted 17 January 2020 - 08:10 AM

For visual or EAA you could go with either one. For imaging the ES will be much better. The AT102 is more of an entry level visual apo. It isn’t really corrected well enough for serious imaging, unless you just want to do narrowband and solar. There is a reason why it is cheaper.

But ultimately, for learning long exposure Astrophotography, you don’t want either of these. Keep the focal length at more like 400-500mm to start, then you can work your way up. So think 70-80mm not 102. And use your savings from getting a smaller scope to get a suitable mount.

Your suggested scope and mount are not good for learning traditional long exposure AP. They are good for visual, or even EAA/“casual imaging” but for any serious AP you want a smaller Apo on a bigger mount. For AP, if your mount costs less than your scope, you are probably doing something very wrong.


Edited by SeattleScott, 17 January 2020 - 08:16 AM.

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#3 Jeff Struve

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Posted 17 January 2020 - 08:56 AM

If I was going to start over again... and AP was a key component of my plan... Id go with the ES 80 Essential and an Orion Sirius mount (or the SkyWatcher equivalent)... the 80 is great for wide FoV visual and imaging... is very forgiving when learing AP... is a great grab n go... and if you get a large scope, does well as a guide scope... 

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#4 925chicago


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Posted 17 January 2020 - 09:07 AM

I've had the ES ED102 essential series triplet for about a year and I've been very happy with the quality of the image for both visual and AP. The quality of the build is very good - the focuser could be better but meets my needs with no issues. It's pretty much all purpose for galaxies and nebulas in term of FOV.  Here's an image of M31 with a 0.8 reducer/flattener:




Good luck with whatever you decide on.

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#5 Devonshire


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Posted 18 January 2020 - 09:44 AM

No opinion on the ED102, but if you get an EXOS2, I'd suggest that you make it the PMC8 model, not the handset model.  The handset model has had a checkered history, but the PMC8 model can do very well.

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#6 SilverLitz


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Posted 19 January 2020 - 01:01 PM

I would not start with the ED102. 


My initial scope choice was not as good a choice; I got an ED102CF after watching some of Trevor Jones excellent AstroBackYard.com videos (highly recommended).  The 714mm FL is a tweenier, too long for most nebulas and too short for most galaxies, and its focuser is seriously lacking.  Last spring, I corrected this by getting an Esprit 100, which I have used mostly with a 0.75x FR/FF at 413mm, f/4.13.  This is an AP killer scope and a terrific bargain (even at $2500), the ED102CF is not.  The Esprit is significantly heavier and requires a beefier mount than the ED102CF (EQ6R-Pro, minimum).


As most will say, for AP you are better off with a 70-80mm APO triplet for your 1st scope, as the FL fits many DSO targets, and they are lighter and easier to guide than longer scopes.  I agree, though I think of the Esprit 100 with a 0.75x FR/FF at 413mm, f/4.13, as a faster, more resolving 80mm (similar FL, but at 100mm for speed/resolution).


A scope that looks very interesting, at a little over $1,000 is the new Sharpstar 76EDPH, with its FR/FF, with a great nebula FL of  ~340mm, and fast f/4.5.



I did much better with my 1st mount a few months later, after more research, much of it on CN, when I got an opportunity to get a ES/Losmandy G11 at a significant NEAF Demo discount.  This has ES's PMC-8 controller system.   PMC-8 works well, and ES support has been great.  Granted the G11 is MUCH more expensive.  In mounts, the SW EQ6R-Pro is the value leader, at $1595 ($1345 sale).  The SW EQ6R-Pro is my beginning AP mount recommendation, as its value cannot be touched.


ES EXOS2 (w/ PMC-8) at sales prices do offer some attraction, but they are much more limited than the EQ6R-Pro, much less an iOptron CEM-60 or G11.  For AP, I expect an ED102CF is its limit, as with cradle, camera, guidescope/cam, FF, and DSLR you will be ~15 pounds; the metal ED102 will add a couple more pounds.  This weight and 714mm FL could pose a challenge for the EXOS2.

Edited by SilverLitz, 19 January 2020 - 01:04 PM.

#7 rkelley8493



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Posted 19 January 2020 - 02:09 PM

Another company to consider is TS Optics over in Germany. They make some very good quality instruments at affordable prices. I've done some business with them a few times, and each time was a success. Despite being over seas, every item I've ordered from them has arrived to my door in less than a week [about 4 days on average].




Edit:  Another thing I forgot to mention, the mount. This decision will be the most important, especially if you plan on getting into astro-photo. Optical tubes come and go, but the mount is your foundation. Orion and Sky-Watcher make some excellent mounts that are affordable and rock solid. 

Edited by rkelley8493, 19 January 2020 - 02:59 PM.

#8 gunfighter48



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Posted 27 January 2020 - 07:32 PM

I have the ES 102 APO and love it. Excellent views with NO color showing with any magnification that I have used. The detail is excellent on the Moon and planets. I don't do astro photography so can't advise you on that.  But for me it was a great choice and it was on sale when I bought it.

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