ES 102mm FCD100 Triplet APO Refractor First Impressions

[rwilkey]

Hi Sky Daddy, if it was me I would go for the ES82, a very good, sharp view through this, can't see how it would be bettered by a 100% FOV, you don't need that for planets or even the Moon.

[Alan64]

On 4/17/2017 at 15:27, Sky Daddy said:

Hey What's Up Alan64, Recieved The Dew Shield From High Point Scientific, Fits Like A Glove, I Don't Much Like The Look It Gives The Scope, But It's Not About Looks. Care And Performance Is The Motivation..... I Also Had A Question For You, I Have A Choice To Make, Concerning Eyepieces. If I Buy This Week I Can Only Afford ES °82 Series, If I Wait A Month Or So I Can Spring For The TV Ethos, No Matter Which Brand I Choose I'm Going With The 4.7mm 2 Inch Barrel Offering..... Should I Bite The Bullet And Wait Or Get The ES °82 EP This Week?  Note* Currently I Don't Have Any High Mag EP's In My Arsenal The Highest I Can Go Right Now Is A 15mm TV Plossl And Barlow It With A TV ×2 Barlow..... I Need A High Mag EP..... Your Wisdom Is Always Greatly Appreciated, Thank You In Advance.....

Glad to hear that the shield fits, and just so.

I'd get this one over the Ethos...

https://www.astronomics.com/televue-35mm-nagler-type-6-eyepiece_p3564.aspx (204x)

Or, the 5mm Nagler... https://www.astronomics.com/televue-5mm-nagler-type-6-eyepiece_p3695.aspx (143x)

...82° they are; nice 'n' spacious.  With the CG-4, you'd have only the RA-axis slow-motion cable to tweak to track anyway, if not motorised.

Otherwise, are you certain you'd want the Ethos sticking this far up out of the diagonal...

https://www.astronomics.com/images/Product/large/19527.jpg

That's entirely up to you, of course.  I like the low-slung oculars myself.

I know that the refractor comes with a 2" mirrored diagonal, but at f/7 you can also make use of a fine 1.25" prism, and for the higher and highest powers...

http://www.highpointscientific.com/baader-t2-maxbright-diagonal-housing-t201c?utm_source=google&utm_medium=cse&utm_term=BAD-T2-01C&gclid=Cj0KEQjwldzHBRCfg_aImKrf7N4BEiQABJTPKEFQDLSd0MpuaAELnfLMlsBMBFyHU34sRRC2MKkOyQoaAvE48P8HAQ

A choice of either a 1.25" or 2" nosepiece when inserting the diagonal into the visual-back...

http://www.highpointscientific.com/baader-planetarium-nose-piece-1-25-t2-t2-14

http://www.highpointscientific.com/baader-planetarium-2-t2-nose-piece-t2-16

...and for the grand finale, this helical eyepiece-holder...

http://www.highpointscientific.com/baader-planetarium-1-25-t-2-focusing-eyepiece-holder-eyehold-2

With that holder, it has a fine-focus helical adjustment, and right there at the diagonal.  Now, the focusser is a two-speeder already, so you might want the click-lock holder for the diagonal instead...

http://www.highpointscientific.com/baader-planetarium-clicklock-1-25-t2-eyepiece-holder-t2-08

...although I have read of some complaints about the click-lock; some like it, some don't.  I think it has something to do with its catching on the barrels of certain eyepieces, making them difficult to remove.  I'd have to research that further in any event.

There's also the bare-bones Baader 1.25" Zeiss-prism...

http://www.highpointscientific.com/baader-t2-diagonal-with-zeiss-prism-t201b

...which can also accept the aforementioned components.  I have the Zeiss-prism myself, and for my 4" refractor...

There's also a 2" Zeiss-prism diagonal, but reviews have it that the 1.25" is slightly better in overall image quality.

...just a wee something to mull over if you're interested.

[Stu]

On 18/04/2017 at 18:28, Louis D said:

Split the difference and get a Lunt Engineering HDC 5 mm 110° x-treme Wideangle Eyepiece.  Reviewers on CN report there isn't much to differentiate it from the 4.7mm Ethos.

That looks interesting Louis. Do you know what the eye relief is light on it? I struggled with the 3.7 Ethos SX even without glasses.

[Chris]

On 4/13/2017 at 13:39, Sky Daddy said:

... Do You Know Where I Can Purchase A Dew Shield Extender? ..

This is how I make dew shields for smaller telescopes. They work well for telescopes up to about 5-6" in aperture, above which you need something a bit thicker/sturdier like camping mat material.

http://www.insideastronomy.com/index.php?/topic/520-diy-dew-shield-for-the-ed80/

EDIT: Forget that, just read that you've bought one.

[Louis D]

9 hours ago, Stu said:

That looks interesting Louis. Do you know what the eye relief is light on it? I struggled with the 3.7 Ethos SX even without glasses.

Probably about the same based on eye lens similarity between the two.

If you're looking for comfortable eye relief with or without eyeglasses and a wide field of view, consider the ES-92 line.  I'm hoping ES comes out with (as Don Pensack reported on CN) 8.8mm and 6.5mm versions of their ES-92 line.  I love the 17mm version.  I'll probably be getting the 12mm version if it goes on sale this Christmas.  If you don't wear eyeglasses, just leave the eye guard flipped up.  It holds your eye at just about the right distance.  With eyeglasses, the view is easy to take in with the guard flipped down.