Search found 460 matches

by oopfan
Thu Dec 26, 2019 1:45 pm
Forum: Gallery
Topic: Tadpole Nebula (IC410)
Replies: 5
Views: 239

Re: Tadpole Nebula (IC410)

by oopfan
Sun Dec 22, 2019 12:24 pm
Forum: Gallery
Topic: Tadpole Nebula (IC410)
Replies: 5
Views: 239

Re: Tadpole Nebula (IC410)

Dave, Thanks. Except for the weather the easy part was image acquisition. It was the processing that was the difficult nut to crack. The last key to success was the star size reduction software. One of these days I'll part with the big bucks for a large format giga-pixel CCD but for now I'm happy wi...
by oopfan
Sun Dec 22, 2019 12:14 pm
Forum: Gallery
Topic: Tadpole Nebula (IC410)
Replies: 5
Views: 239

Re: Tadpole Nebula (IC410)

Hi Nick, Thanks. I like your wide FOV. The nebula almost looks like the Monkey Head using that particular camera orientation. Nice! I agree that NB is not for everyone especially if you are into short time frames. Sara Wager routinely uses 30-minute exposures at bin2 but she uses 3nm filters so less...
by oopfan
Sun Dec 22, 2019 3:08 am
Forum: Gallery
Topic: Tadpole Nebula (IC410)
Replies: 5
Views: 239

Tadpole Nebula (IC410)

It's been a long time since I last posted to the SharpCap forum. I still use SharpCap but for purposes other than image capture. I do use it for polar alignment, and for periodic error correction determination of my 50 year old mount, but also recently for guiding assistance. Within the past couple ...
by oopfan
Wed Apr 03, 2019 7:05 pm
Forum: Gallery
Topic: unguided galaxies
Replies: 7
Views: 932

Re: unguided galaxies

Nice!

There is a lot of nebulosity that we are not seeing because you have the black level set too high -- that is why outer space is black. Can you reprocess it so that we can see space as a shade of gray?

Thanks,
Brian

PS: What's worse: the sky glow from San Antonio or Austin?
by oopfan
Wed Apr 03, 2019 4:49 pm
Forum: Altair Cameras
Topic: Altair 290M sensor analysis has dramatically changed
Replies: 1
Views: 640

Altair 290M sensor analysis has dramatically changed

Robin, When SharpCap 3.1 Beta was released October 2017 I jumped on the bandwagon. I kept up with each minor revision and on January 9, 2018 I ran sensor analysis on my new Altair 290M (see attachment entitled "Altair GP290M Sensor Analysis MONO12 2018-01-09.png".) Afterwards I used The Brain a few ...
by oopfan
Tue Apr 02, 2019 4:04 pm
Forum: General Discussions
Topic: White-balancing Optolong LRGB filters with Altair 290M
Replies: 5
Views: 960

Re: White-balancing Optolong LRGB filters with Altair 290M

I decided to try out the empirical approach to find white balance as described here: http://kellysky.net/White%20Balancing%20RGB%20Filters.pdf Last night I took 100x 2s frames with each RGB filter of a magnitude 8.23 G2V star in Ursa Major: HIP 60268. I chose the best 10 frames for each filter, cali...
by oopfan
Sun Mar 31, 2019 9:19 pm
Forum: Gallery
Topic: M101 in LRGB
Replies: 26
Views: 2214

Re: M101 in LRGB

Hi Andy, Thanks for the FITS file. Here is what I discovered: 1. The maximum pixel value of 55920 as reported by FITS Liberator are hot pixels, not stars. 2. The brightest star in the frame that I could match against C2A planetarium software is magnitude 11.015 at maximum pixel value of 22800 ADU. I...
by oopfan
Sun Mar 31, 2019 2:11 pm
Forum: Gallery
Topic: M101 in LRGB
Replies: 26
Views: 2214

Re: M101 in LRGB

Andy, One more thing: In the image screenshot you posted, FITS Liberator set the initial white level at 1800.01 but notice that there are lots of pixels brighter than that in the histogram. One thing you can do is check the box labeled "White clipping (green)" middle right-hand side of the app. Zoom...
by oopfan
Sun Mar 31, 2019 12:58 pm
Forum: Gallery
Topic: M101 in LRGB
Replies: 26
Views: 2214

Re: M101 in LRGB

Hi Andy,

When you are sampling the peak ADU of a star, are you zooming in to make sure that you are picking the right one?

Thanks,
Brian