A gathering place for astronomy enthusiasts

Observing Report - First Light - Explore Scientific 24mm 100 Degree eyepeice

I received the UPS package at my office. The shipping carton was the typical cardboard carton but this one was dyed jet black. I slit the cellophane packaging tape with my knife and lifted the carton flaps. Beneath pale green cushion pillows  was a interestingly constructed box that was covered in the graphics of a colored star chart. The lid of the box was hinged and articulating so that it lifted and then dropped back away from itself. Interesting box. I was immediately reminded of the beautiful design in packaging of Apple Products. This box was definitely a keeper. :)

The eyepiece was held securely inside by two pieces of molded Styrofoam. It was of considerable size and weight (the eyepiece, not the Styrofoam.) (heehee) It's two inch barrel was machined with a bevel at the top to help keep it from slipping out of a diagonal or focuser tube. At 41.5 oz it'll require a rebalancing of your mount, but trust me when I say it's worth it.

First target was M45 (the Pleiades) - the Seven Sisters turned into a field of much more. For the first time I could view all seven of the main stars in a single field of view. In the 6" refractor I started counting stars and gave up when I reached 80. There were at least 100 stars visible. I had to strain my eye from side to side and up and down in order to see the stars out at the edges of the field of view. Imagine that you're peering out of a ship's porthole trying to see the bow and stern from your mid-ship's cabin and you'll understand what it's like to view through this eyepiece. It's impossible to take in the entire field of view but what I quickly realized is that framing a wide-field object with lots of space around it really adds something to the view. Steven Aggas emailed me that the field of view was nearly what he would have with his 31mm Nagler but with a nice boost in power. He was impressed with the 14mm 100 degree eyepiece that I took to the Overgaard Star Party last year and he is anxious to try this one too. I'm anxious for that view myself. Steven owns a 36" f/4.5 scope with unforgettable views.

The double cluster was easily framed inside the field of view with lots of space around the edges. M42 filled a large portion of the eyepiece with the trapezium stars showing up as four tack-sharp pinpoints of light. The CG-5 mount was a little shaky and bumping the eyepiece cup caused some vibrations that took a second or two before they settled out. I couldn't really study the view and look for a fifth or sixth star. On bright objects like the moon and Jupiter I could see some color fringing that moved around the edges and changed color as my eye drifted off-axis from the light cone. I would think that the fringing is more a result of the Doublet lens then the eyepiece. I just never noticed it changing dynamically or moving around an object as obviously as now. The scope is relatively new to me so I'm learning it's nuances.

The 16" Lightbridge primary is due back from Nova with new coatings and I'm super-psyched to slip this eyepiece into the light path from a dark sky site. :)

This was just first light and more chances to observe will reveal things that I love and maybe some things that I don't but so far I love this eyepiece. It's not a huge surprise since the 14mm 100 degree eyepiece rarely was taken out of the scope over the past three years. Very soon I'll be ordering the 9mm and at some point in the future I'll get the 5.5mm. That will complete my eyepiece collection for years to come. :)

Explore Scientific ROCKS! imho :)

Views: 62


You need to be a member of StarParty to add comments!

Join StarParty

Comment by Stephen Krell on April 8, 2014 at 11:18am

Good to hear, I,ve been looking this line over and several Club members swear by these as well

Comment by Stefan on March 18, 2014 at 5:12pm

Joe, nice report on the EP . It looks like you are gearing up for the spring and summer,  good luck with the new and newed gear. Clear skeis, Stefan

Comment by Richard A Flinn on March 18, 2014 at 7:56am

"Explore Scientific ROCKS!"

I'd certainly have to agree with that statement. I love my ES82 24mm and can only imagine what the 100* is like.

Great report Joe. So whats the lowdown on the new scope? 

I didnt know you had sent your 16" mirror off to Nova. Did you get it tested first? I'd be interested in hearing how it worked out!

Congrats on all the new gear and the "like new" mirror! :)


StarParty created this Ning Network.

© 2016   Created by StarParty.   Powered by

Badges  |  Report an Issue  |  Terms of Service