SharpCap Forums

Greetings to all!

35 degrees altitude, right above a streetlight, and Moon at half-phase. Bortle 8

So not the greatest conditions, but I am pleased with this 'save as seen' EAA capture.

21.6 minutes total, 5 sec sub, 400 gain.

Using Beta version of Sharpcap just released. Tracks comet, and lets the stars trail. Code has the ability to eliminate stars, but the brightest part of the nucleus of the comet is about the same dimension as some stars, so they remained to trail.

The length of the trails shows the 'speed' in RA/DEC this particular comet is traversing through the solar system, never to be seen again (parabolic trajectory, not closed, not even 50,000 years).

AT80ED(480mm FL)/asi294mc-pro(-10C) (parameters attached)

Can clearly see both the dust tail (sublimation from sunlight and interaction with the solar wind) and the ion (plasma) tail (solar wind electrons ionize the gas) which is tied to the magnetic field lines from the Sun.

I do not think I could have gotten the ion tail at 80mm/480mm unless I was able to track the comet for as long as I did (over 20 min).

Bob
https://www.cloudynights.com/topic/8576 ... p=12457319

https://www.cloudynights.com/topic/8576 ... p=12457319

Great capture Bob!
I want to test the tracking here too but sadly it's only clouds and clouds alone here. Haven't seen the comet at all

Menno

Thanks for the compliment

Yes, even in AZ the clouds have been quite dense for some time. Today (Sunday) is the last clear day for some time.

I hope it clears up for you soon!

Bob

Excellent capture under difficult conditions!

Until you pointed it out I hadn't realized that one of the advantages of Robin's comet tracker is that the length, start and end of the star trails (if you choose to leave them in) are themselves useful for measuring the DEC and RA velocity of the comet.

Tim

"are themselves useful for measuring the DEC and RA velocity of the comet"

precisely! Thanks for mentioning it!

Bob

Hi,

nice image - I do have an idea to introduce the option to try to stack the stars separately in the future (providing I can find a nice way to separate the stars out from the rest of the image).

I got a similar result from about 12 minutes total exposure on my first chance to test this out for real last night.
cheers,

Robin

To isolate stars and stack separately would be a GREAT feature!

Please, if you have the time and inclination it would be wonderful if you were to consider it!

Excellent image, bTW. What scope/camera/bortle index was this taken? The ion tail is awesome!

thanks for all you do,

Bob

Hi Bob,

this was taken with an SVBony SV605CC camera (IMX 533 chip) and an Altair 70EDQ f/5 quad apo. No darks or flats, but the camera set to -5C. I think the individual exposures were 8s

I would guess our skies are about Bortle 5 - I really should do a measurement some time.

I was very pleased with how well this came out (although the stretch to bring out the tails does tend to make the star trails a bit fat).

cheers,

Robin

Thanks for the info! I agree, it is an excellent capture. Those svbony cameras really are very nice!


Bob

Finally got some decent weather in Wisconsin last night. Clear but quite cold.

Full moon was an issue so any details in the tail were washed out. Also i'm Bortle 7 (ugh).

Camera is a ZWO ASI183MC.
Comet tracking feature (beta) is a nice addition to the sharpcap software.