IC 5070 the Pelican Nebula

[Pete]

Tuesday, 26 Jul 2022

I’d done the Pelican last year thru the Hyperstar and the results were not pretty. It’s well positioned for a re-do.

The lower dome shutter and all other light trespass tools were utilized. And with the 102 mm refractor the Optolong LP filter is mounted.
Tonight’s sky is a clear and dark and moonless.

Initial imaging attempt was 3 min, 120 gain, -5°C. But as with the previous time out with this setup there’s just not enough exposure. Changed over to 5 minute frames.

Imaged from 21:24 – 00:24 with a total exposure of 37 X 5minutes. 36 frames used. That’s 3 hours even.

In at 00:32. It’s 66°F.

Upon firing up the laptop on 7/27 THE FILES ARE MISSING. Looks as if I’d forgotten to save? Really bummed.

Saturday, 30 Jul 2022

Tuesday’s live stack looked lovely. Gonna try the Pelican again. The sky’s clear, dark and moonless. Imaged from 21:09 – 00:23 hours, with a total exposure of 40 X 5 minutes. 7 frames then discarded.

IC 5067 full size lo res b.jpg (2.13 MiB) Viewed 673 times

IC 5070 – the Pelican Nebula
21:09 – 00:23 hours July 30 – 31, 2022
40 X 5 minutes (with 7 frames subsequently discarded) unbinned, -5C, 120 gain, 1 sec guiding.
Explore Scientific 102mm triplet with Optolong LP-pro filter and ASI 2600MC-P camera
Wishing Star Observatory Barrington RI USA

While I’m sure that folks imaging throughout the night doing LRGB will have a whole different image this is spot-on as far as my imaging goals. And drastically superior to last year’s image taken with the Hyperstar.

Analysis:

While saving the live stack frames I noticed that the frames were being saved to a completely different location than what I’d programed. And I was unable to change the SharpCap file saved location. Exploring further, the images from 7/26 were also hidden in this new file.

Processing the recovered data:

220726 IC 5070 11X8 lo res.jpg (828.66 KiB) Viewed 673 times

Same quality as from 7/30 but perhaps a bit better processing.

2 birds with not 1 stone but 77 exposures.


IC 5070 the Pelican Nebula
IC 5070 (aka the Pelican Nebula) is a cloud of hydrogen gas some 1,800 light years distant. This nebulosity bears a resemblance to a pelican, giving rise to its name. IC 5070 is classified as an emission nebula because light from young energetic stars is slowly transforming cold gas to hot and causing the gas to ionize and glow. (Red is the primary spectrum emission line of Hydrogen gas.) Particularly dense filaments of cold gas are seen to still remain. The Pelican is much studied because it has a particularly active mix of star formation and evolving gas clouds.
Millions of years from now this nebula might no longer be known as the Pelican, as the balance and placement of stars and gas will leave something that appears completely different.

[Bruce D]

Very nice Pete! Have you given up on the hyperstar? The LX? You are getting beautiful images out of that little refractor!

[Pete]

No Bruce, I've not given up on the Hyperstar. It does suffer from some strange flare and rainbow striations, but only on some objects. To coin a phrase: When it works it's very very good, but when its bad it's horrid. Just gotta figure out which targets are appropriate.

[menardre]

Pete

Great job with the Pelican nebula. Vibrant colors and nice pin point stars.

Well done !!

I really enjoy imaging through my refractor for extended objects such as nebulae. Looks like you are getting good results from your refractor.

Roger

[Pete]

Hi Rog,

I'd been looking at piggyback refractors because of the ongoing frustration with the Hyperstar. The custom camera to Hyperstar mount solved much of the problem but I was getting tired of the struggle. Bought this Explore Scientific 102 mm f/7 Essential Triplet in February when it went on sale. A steep 25% discount. While not a high-end triplet such as yours this little scope is color free and relatively sharp. Plus the focal plane image circle just covers the camera's C size chip. Weight was my primary piggyback constraint but considering that the Hyperstar and counterweight total more than 20# going with a 9# piggyback was probably conservative. While Explore Scientific strongly advocates a field flattener the coma is, to me, minimal and acceptable.

While my triplet works, I'd be open to upsizing to 120 - 130mm if they had faster optics. But they're also all f/7 or slower. Like most things in life, it's a trade-off.

[Bruce D]

Pete I have a Baader field flattener, not even sure where I got it- I was fiddling with it at Stellafane and it's too big for a 1.25" EP, too small for a 2" EP. I was trying to figure out what the heck I could use it for as it turns out to be for a DSLR as it has a T2/M42 connection. Long story short (I was thinking about giving it away- sorry Tom) it turns out my fiddling revealed if you remove the nosepiece on your ZWO camera it screws right in, and the OD fits a 2" EP holder perfect. I was invigorated (and frustrated) at Stellafane and hope to get active again soon BUT, you are welcome to borrow this for a week or so and see if it works for you and if the improvement is worth the investment. I think your pictures look great, but I don't know if you had to crop the edges because of aberrations.

[Pete]

Thank you Bruce. I'd like to give it a try. The images I post are usually the full frame ones but I crop everything to 8.5 X 11 for printing and sometimes its the cropped image that gets posted. Either way there's very minimal coma. Also while giving this a try I'm a bit pessimistic regarding the correction. Every telescope has a different degree of coma, depending on f/ ratio and other stuff, so I suspect that you need a specific optic for a specific telescope/camera combo and it may not be one-size-fits-all.

That said, let's give it a try. Your offer is appreciated.

[Bruce D]

Sure Pete, perhaps I can drop it off tomorrow morning- I'll text you