Jump to content


Photo

Neptune + Triton f10 IR685 9/4/13

  • Please log in to reply
17 replies to this topic

#1 sfugardi

sfugardi

    Gemini

  • -----
  • Posts: 3059
  • Joined: 30 Sep 2006
  • Loc: CT

Posted 04 September 2013 - 12:25 PM

Taken last night in 3/5 seeing at Neptune's transit approx 34deg altitude. Good collimation and temperature stability did not seem to override the average seeing. I first tried the Flea3 at 4fps but for some reason the actual was stuck at 1.2 so I went back to the ASI120MM. I also tried 16bit but the brightness went strange and so did the frame rate. So going back to avi mode, I focused off Triton with a temporarily extended exposure, then went back to 4fps collecting 9,999 frames with an average histogram of 45%. The video was cropped with the Castrator before stacking 5K frames in AS2!. I processed Triton separate from Neptune using slightly heavier Reg6 sharpening, then combined in PS. I tried different size stacks and drizzle settings, but could not find the white spot being reported here. I suspect, 4/5 seeing or better is needed to have a legitimate chance.

Regards,
Steve

Attached Files



#2 corpusse

corpusse

    Viking 1

  • -----
  • Posts: 810
  • Joined: 11 Apr 2010
  • Loc: Mississauga, Ontario, Canada

Posted 04 September 2013 - 12:55 PM

Still a nice capture giving trying circumstances. Are you sure the white spot was facing us at the time? I still gotta try my scratched to hell 685 filter as I wait for a new one...

#3 bunyon

bunyon

    Gemini

  • *****
  • Posts: 3206
  • Joined: 23 Oct 2010
  • Loc: Winston-Salem, NC

Posted 04 September 2013 - 01:48 PM

Very nice. Neptune is a challenge.

#4 Kecktastic

Kecktastic

    Skylab

  • *****
  • Posts: 4179
  • Joined: 16 Jan 2010
  • Loc: Broken Hill NSW Australia

Posted 04 September 2013 - 06:04 PM

Nicely done Steve, a top effort for the alt.

Cheers
Trevor

#5 Kokatha man

Kokatha man

    Fly Me to the Moon

  • *****
  • Posts: 6780
  • Joined: 13 Sep 2009
  • Loc: "cooker-ta man" downunda...

Posted 04 September 2013 - 07:26 PM

If your efforts count for anything you'll crack something with Neptune re the "bright spot" for sure Steve..! :waytogo:

#6 sfugardi

sfugardi

    Gemini

  • -----
  • Posts: 3059
  • Joined: 30 Sep 2006
  • Loc: CT

Posted 05 September 2013 - 10:15 AM

Andrew, Paul, Trevor, Mo, Thanks for the compliments and support! I'm not real sure of the white spot orientation vs time. While it is fun to try imaging these distant planets in search of finely resolved detail, usually you just end up with nice disks...

Regards,
Steve

#7 Pete Gorczynski

Pete Gorczynski

    Messenger

  • *****
  • Posts: 411
  • Joined: 09 May 2008
  • Loc: Oxford, CT USA

Posted 05 September 2013 - 06:26 PM

Nice work, Steve. Have you tried a stack of less frames? You are probably right about having at least 4/5 seeing to have a reasonable chance with this planet.

Regards,

Pete G.

#8 John Boudreau

John Boudreau

    Viking 1

  • *****
  • Posts: 857
  • Joined: 06 Apr 2008
  • Loc: Saugus, MA

Posted 05 September 2013 - 07:16 PM

A capture that gives a clean image of both Neptune and Triton with low noise such as this one is always a nice piece of work! At this time, I don't know if there is a predicted drift rate for this spot--- or if it's indeed a spot or spots. The image from PDM may be showing a bright section of a band---- we simply may be seeing that feature, and it could just be appearing as a simple spot to us due to our limited resolution with our smaller aperture scopes.

Your image certainly shows the southern hemisphere as being brighter than the northern, which is correct --- at least for this year.

#9 sfugardi

sfugardi

    Gemini

  • -----
  • Posts: 3059
  • Joined: 30 Sep 2006
  • Loc: CT

Posted 06 September 2013 - 06:12 AM

Pete, thanks for the feedback. I went back and reprocessed stacks ranging from 500 to 5000. I also reverted to Reg5 since the brightness on Reg6 kept changing for some reason. My new Neptune sharpening is simple, slider 6 max. For final sharpening, I used Images Plus 13x13 adaptive Lucy Richardson. This time no noise reduction was applied since it would smooth out any detail. Using this method, there is clearly a white spot in all images!

John, Thanks! By focusing the camera on Triton with an extended expoure time, you are guaranteed of the best possible focus, at least at the start of the avi run. As the temperature cools during the 40min run, you need to slightly tweak the focus count higher to compensate.

I've got legitimate good seeing tonight and will repeat this on Neptune and Uranus. Attached is my Neptune/Triton with "white spot" matrix by frame stack. I am convinced that this data must be carefully processed in order to bring out the detail.

Regards,
Steve

Attached Files



#10 sfugardi

sfugardi

    Gemini

  • -----
  • Posts: 3059
  • Joined: 30 Sep 2006
  • Loc: CT

Posted 06 September 2013 - 06:14 AM

Here is my Neptune processing procedure. Please reply back if you can make improvements.

Step 1: Precastrate the data to make sure AS2! aligns properly

Attached Files



#11 sfugardi

sfugardi

    Gemini

  • -----
  • Posts: 3059
  • Joined: 30 Sep 2006
  • Loc: CT

Posted 06 September 2013 - 06:17 AM

Using AS2! You need to choose planet gradient 6, global and the smallest px box of 25 adjusting the normalization % to avoid burning in Registax post processing, 1.5x drizzle.

Attached Files



#12 sfugardi

sfugardi

    Gemini

  • -----
  • Posts: 3059
  • Joined: 30 Sep 2006
  • Loc: CT

Posted 06 September 2013 - 06:18 AM

Using Reg5 and gaussian, crank slider 6 to 100

Attached Files



#13 sfugardi

sfugardi

    Gemini

  • -----
  • Posts: 3059
  • Joined: 30 Sep 2006
  • Loc: CT

Posted 06 September 2013 - 06:19 AM

Final sharpening with adaptive 13x13 LR using Images Plus

Attached Files



#14 AstroDan2015

AstroDan2015

    Viking 1

  • -----
  • Posts: 606
  • Joined: 09 Aug 2014
  • Loc: Racine, Wisconsin

Posted 06 September 2013 - 03:13 PM

Really great processing Steve! Looks like you captured the white spot, that's remarkable work!

Clear skies, Dan :)

#15 sfugardi

sfugardi

    Gemini

  • -----
  • Posts: 3059
  • Joined: 30 Sep 2006
  • Loc: CT

Posted 08 September 2013 - 09:11 AM

Dan, thanks! It's been fun trying to image these sub-5" disks so hopefully my latest refinements will help with Jupiter as it eventually will rise above my tree line. Hope all is well with you and go Packers!

Regards,
Steve

#16 sfugardi

sfugardi

    Gemini

  • -----
  • Posts: 3059
  • Joined: 30 Sep 2006
  • Loc: CT

Posted 11 September 2013 - 08:01 PM

Here's my reworked 3K stack showing the white spot using my posted processing method.

Regards,
Steve

Attached Files



#17 bunyon

bunyon

    Gemini

  • *****
  • Posts: 3206
  • Joined: 23 Oct 2010
  • Loc: Winston-Salem, NC

Posted 11 September 2013 - 08:39 PM

Excellent work, Steve.

On regi 6: if the histo is less than half full, it automatically stretches the data. And, in my opinion, badly. I usually have these dim things normalized to 55% in AS2, then stretch manually after regi.

Although, I thought LR deconvilution gave a better result than regi wavelets in my data.

#18 ToxMan

ToxMan

    Mercury-Atlas

  • *****
  • Posts: 2766
  • Joined: 23 Jan 2011
  • Loc: Tucson, Arizona, USA

Posted 11 September 2013 - 09:06 PM

Great images and wonderful contribution. Thanks, Steve. I settled for a visual on Neptune last night before setting up to image Jupiter. And, I thought that was difficult...






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics