Exp Sci ED80 Apo Triplet - First Impressions

[cloudsweeper]

It looks good - well finished, smart - but was much smaller than I'd expected.  Not a bad thing, mind you, after getting a Dob which in its box nearly filled the hall!  The smallness is accounted for because of the retracted dewshield, and the need for two extension tubes, besides the inherent short focal length of course.  All this makes it very portable and manageable.  It comes with a high transmission 2" diagonal and a dual speed low profile R&P focuser with tension adjustment and lock.  (I was keen to avoid a Crayford type, as I have had issues with slipping out of focus under load.)  The narrow (Bresser type?) finder shoe had to be replaced with an Omegon mount in order to accept my RDF with its separate, wider shoe.

A couple of days ago I had a quick look at Luna as it dodged the clouds.  The framing was lovely with well over 5deg of field, then at x160, more detail was sharp and clear.  And there was no sign whatsoever of CA.  But no stars yet.....

5.45am this morning (17/1) conditions were good, so enthusiasm prevailed and the ED80 was placed on the Skytee II.  At over 5deg (and x11 - x16), locating objects and hopping were quite easy.  I aimed for M13 in the east and got straight on it.  Surrounding stars were pinpoints, losing just a little sharpness at the edge of the field.  This was restored by focusing, and suggested some field curvature (to be expected).  I noticed that some eyepieces also produced a little astigmatism, except the big Meade 5000s, although I didn't run exhaustive tests.

At x80, tiny specks around M13 were resolved.  After an easy hop, another Hercules GC was easily found - M92.  Again, the fuzz showed some detail at higher mag.

There are other 'scopes for mag and aperture, so I am very pleased with this little addition to the stable with its sharp, widefield views, lack of CA, and steady focus.  It will serve well as a guidescope with the 8" Cat in manual mode.

By 7.00, the sky was getting lighter, so this very satisfactory trial run came to an end. 

Doug.

 

 

[Victor Boesen]

Sounds like a nice first light! Is it the version with the "FCD-100" type glass?

[cloudsweeper]

37 minutes ago, Victor Boesen said:

Sounds like a nice first light! Is it the version with the "FCD-100" type glass?

Hello Victor -

It's FCD 1, air-spaced triplet, alu tube, no finder, no case - but here's a stand I cobbled together for it.................

Doug.

[Victor Boesen]

10 minutes ago, cloudsweeper said:

Hello Victor -

It's FCD 1, air-spaced triplet, alu tube, no finder, no case - but here's a stand I cobbled together for it.................

Doug.

Its really a nice looking refractor and its size is still very manageable. I am considering the FCD-100 type for a nice compact refractor for traveling also because of its 2" focuser capability which would give me absuper wide field with my 24mm 82 degree.

[Astro Imp]

Hi Doug,
Always nice to get the new toys up and running. 
Good to read you're pleased with this little beauty.
As you were out early this morning I'm surprised you didn't point it at Venus or is she hidden from your observing position?

[cloudsweeper]

14 minutes ago, Astro Imp said:

Hi Doug,
Always nice to get the new toys up and running. 
Good to read you're pleased with this little beauty.
As you were out early this morning I'm surprised you didn't point it at Venus or is she hidden from your observing position?

Yes Alan - I only spotted Venus when I put out the recycling at the front of the house!

Doug.

[sloz1664]

Cricky that is tiny. My Altair Astro 80 Triplet looks like a Mother Ship compared to the Exp Sci.

Steve

[michael.h.f.wilkinson]

Very nice first light report. I must say I love my 80mm F/6 APM triplet. Very versatile and sharp. The views with the 31T5 and 22T4 Naglers are just breathtaking.