First Light - ES 80mm f/6 - Serendipitous NEOWISE

[Hankmeister3]

Several days ago I rescued my 80mm f/6 Triplet ED APO Explore Scientific refractor that I had stashed in the back of a closet about two years ago and thought I'd piggyback it on my Quattro 8 to see what kind of AP performance I could squeeze out of it. Overall, I was a bit disappointed with the excessive amount of coma this particular triplet glass had to offer. Chromatic aberration was low to non-existent, the central image was good and crisp, but when I post on the DSO forum a sampling of DSO images I grabbed last night and this early morning you'll see what I mean about the excessive coma. However, and it's a big however, my Baader coma corrector for my Quattro 8 f/4 astrograph and my Guan Sheng 8 f/5 might be able to come to the rescue. In a few days I'll attempt another sky safari to see if the coma corrector does the trick.

That said, I did stumble into actually capturing my first images of Comet NEOWISE which wasn't on my to-do list for the evening. I really didn't know exactly where it was in the evening sky and how viewable it would be from my somewhat tree-line horizon location at the Penfield/Middlefork dark site. I had just finished putting my equipment together when a young couple drove up into the parking lot. It was getting pretty dusky and I asked if they were there to to see the comet. Yep. So I pointed them toward the general direction I thought it might be (at the time I had thought it had already set behind some trees) where a line of trees stood about half-a-mile away. After a minute the young man, Ryan, thought he saw it naked eye to the northwest where I had generally pointed. I retrieved a pair of Nikon 7x50 binocularas and let him borrow it. Yep, that was it. When he pointed where it was, I could see it myself. Though I hadn't performed a polar alignment, I knew I was roughly within a couple of degrees of Polaris given the fact I generally set up in the exact same area of the rock parking lot.

So I hurriedly manually slewed the telescope, which originally refused to move (yikes!) and finally got it pointed in the vicinity of NEOWISE. Unfortunately, I didn't shift from BULB mode to AE mode on my Canon 77D so I was shooting blind (though aided by my finderscope which wasn't exactly aligned with the piggybacked ES 80mm refractor). This image is the very first image I grabbed of NEOWISE but the comet was dropping fast behind the trees due to sidereal motion. Unfortunately I lost my 50-50 chance of hitting the right slew button and my next shot had more foreground tree silhouettes and less comet! By the time I was able to roughly frame the comet it's head was already in the tree line. The second image is the last frame I took, all within a span of three minutes.

Despite the troubles, it was still a kick in the pants because I actually captured an image of NEOWISE which I wasn't planning on doing for the next three or four days until it climbed higher into the sky. Now I'm committed to finding a weather/cloud window at sunset somewhere within a two hour drive of my home in order to capture more NEOWISE images. Until I get the coma issue figured out for the ES 80mm, I'll remount my Meade 70mm f/5 astropgraph which yields a wider field of view anyway and try to follow the progression of this comet as it tracks through the sky.

Sorry for the novel-length treatment, but the event was so extraordinary and serendipitous I thought it was worth mentioning in some detail.

Explore Scientific 80mm f/6 APO triplet refractor
Canon EOS 77D unmodified
15.3 seconds, ISO 1600 (I was in such a rush, I didn't think to reset the Canon from it's deep sky Bulb mode at ISO 1600)
No filters, Sidereal rate only

[TheButcher]

Very NIce Henry and I love how you tell your detailed imaging adventures.

[JayTee]

I own that particular refractor and I would highly recommend the use of an FF with it. I own both the Hotech SCA2 and the Astro-Tech AT2FF. Both of these work well but I prefer the AT2FF.

Cheers,
JT

[Juno16]

That is really a cool setup Henry!

I would love to have a ED80 APO. I really like the fov. Looks like it is your guide scope!

Great image! Still haven't been able to spot this bugger. Thanks for the photo and nice write.

[Caddman]

That's a great first image. Hopefully, you won't have to rush on your next attempt.

[Hankmeister3]

Hey, JT. Have you imaged with your ES 80mm? If so, would you mind posting an image or images on this thread?

[JayTee]

Sure,

Here are three images that are in my gallery page.

The Eta Carina Nebula


Omega Centauri Globular


M8 and M20. This is not a composite, the FOV is that wide! Believe it or not, the entire Eta Carina Nebula is larger than the distance between M8 and M20

All three images were taken through the ES 80mm f/6 APO using a Canon T3i and the Astro-Tech AT2FF FF.

Cheers,
JT

[Hankmeister3]

Thanks, JT! It's almost hard to believe that a little ol' 80mm refractor can deliver such wonderful astro-photos like those you posted. I remember back forty years ago when everyone was aperture crazy ... including myself with my 10-inch f/5.5 Meade mirrored Newtonian! Little 70mm, 3-inch and 80mm glass were scoffed at as being "toys". Of course the vast majority of consumer-grade refractors were two-element achromats and not triplet apochromatics, mostly cemented and not air-spaced with Schott glass for one optical element. I don't know if "Schott glass" was even around that long ago for amateur astronomical use, at least not here in the States. I guess it wasn't until after the Berlin Wall fell in 1991/92 that Schott glass optics became more popular throughout the world. Just my limited read on things. I'll stand corrected on this.