Search found 1321 matches

by oopfan
Mon Apr 27, 2020 11:20 am
Forum: Live Stacking
Topic: Dark universe swamped by colured pixels
Replies: 13
Views: 4425

Re: Dark universe swamped by colured pixels

Hi, I hate saying this but my ASI120MC died within a year. It doesn't even make a good doorstop. It just sits with my stack of stuff reminding me of the 'bad old days'. I think I pushed it beyond its comfort zone. In other words, I may have killed it taking 120s exposures. either that or ZWO has pro...
by oopfan
Mon Apr 27, 2020 3:32 am
Forum: Deep Sky Imaging
Topic: Recreating Edwin Hubble's discovery of a Variable Star in the Andromeda Galaxy
Replies: 4
Views: 1579

Re: Recreating Edwin Hubble's discovery of a Variable Star in the Andromeda Galaxy

Hi Steve, AAVSO's official designation is "M31 V0619". They report that its magnitude fluctuates between 18.5 and 19.8V. That is faint. I've known that my scope/cam can see down to 18th magnitude at my Bortle 5 site but can it see down to 19th magnitude? What makes things worse is that the...
by oopfan
Sun Apr 26, 2020 9:28 pm
Forum: Deep Sky Imaging
Topic: Recreating Edwin Hubble's discovery of a Variable Star in the Andromeda Galaxy
Replies: 4
Views: 1579

Re: Recreating Edwin Hubble's discovery of a Variable Star in the Andromeda Galaxy

Hi Robin, Yes, I wondered the same. I searched and found an answer: https://www.nasa.gov/mission_pages/hubble/science/star-v1.html There is lots to read but allow me to pull a quote: The astronomer [Hubble] spent several months in 1923 scanning Andromeda with the 100-inch Hooker telescope, the most ...
by oopfan
Sun Apr 26, 2020 8:34 pm
Forum: Gallery
Topic: M13 & M51 LRGB, each 2h 55m integration
Replies: 2
Views: 993

Re: M13 & M51 LRGB, each 2h 55m integration

Gorgeous color, Dave! You nailed the exposure on M13, individual stars in the core, nothing blown out. Great work!

Brian
by oopfan
Sun Apr 26, 2020 5:12 pm
Forum: Deep Sky Imaging
Topic: Recreating Edwin Hubble's discovery of a Variable Star in the Andromeda Galaxy
Replies: 4
Views: 1579

Recreating Edwin Hubble's discovery of a Variable Star in the Andromeda Galaxy

On October 6, 1923 renowned astronomer Edwin Hubble discovered a pulsating star in the Andromeda Galaxy which quickly led to the revolutionary discovery that M31 is a galaxy unto itself 2.5 million light-years away, and not a gaseous cloud of stars within our own Milky Way. I dipped into my archive ...
by oopfan
Sun Apr 26, 2020 2:24 pm
Forum: Live Stacking
Topic: Dark universe swamped by colured pixels
Replies: 13
Views: 4425

Re: Dark universe swamped by colured pixels

Like Dave I too started with the ASI120MC. I've attached a single 120-second light frame of M33 Triangulum Galaxy so you can see how the sensor was swamped by hot pixels. This camera is not designed for Deep Sky. It's best for Lunar, Planetary, and for guiding. You can still get decent Deep Sky imag...
by oopfan
Sun Apr 26, 2020 1:08 pm
Forum: Deep Sky Imaging
Topic: Eclipsing Binary Star System: GK Boo
Replies: 5
Views: 1692

Re: Eclipsing Binary Star System: GK Boo

Today's NASA Astronomy Picture of the Day (APOD) is a celebration of the 100th anniversary of astronomy's Great Debate held at New York's Museum of Natural History between Harlow Shapley and Heber Curtis. Shapley argued that the Milky Way was the size of the known universe and that the Andromeda Neb...
by oopfan
Sun Apr 26, 2020 12:17 pm
Forum: Polar Alignment
Topic: Polar aligning from ANY part of the sky
Replies: 14
Views: 11639

Re: Polar aligning from ANY part of the sky

This has got me thinking...

Let's suppose I was able to actively guide in both RA and DEC. If my polar alignment is off by 1 degree can I still get decent astrophotos using guiding software like PHD2? In other words, how critical is PA when you can guide?

Brian
by oopfan
Sat Apr 25, 2020 10:41 pm
Forum: Polar Alignment
Topic: Polar aligning from ANY part of the sky
Replies: 14
Views: 11639

Re: Polar aligning from ANY part of the sky

I visited the website. Accuracy within 30 arc-seconds is not good enough for me. I can only speak for myself and one other person but we do not actively guide. We rely on the accuracy of our polar alignment and periodic error correction. My mount is 50 years old. I have no control over the declinati...
by oopfan
Sat Apr 25, 2020 9:35 pm
Forum: Deep Sky Imaging
Topic: Eclipsing Binary Star System: GK Boo
Replies: 5
Views: 1692

Re: Eclipsing Binary Star System: GK Boo

Thanks everyone for your encouragement. I was hoping to capture more data last night but the forecast fell apart as time approached. In the meantime I wanted to briefly discuss the differences between the two applications I used in my original post: 1. AstroImageJ, aka AIJ, allows me process my raw ...