Jump to content

  •  

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.

Photo

Neptune & Triton 2015.07.20 with bright spot

This topic has been archived. This means that you cannot reply to this topic.
23 replies to this topic

#1 Marc Delcroix

Marc Delcroix

    Viking 1

  • -----
  • topic starter
  • Posts: 543
  • Joined: 26 Aug 2007

Posted 20 July 2015 - 02:12 PM

Dears,

First try to catch the bright spot on Neptune which was detected on Calar Alto, with my new ASI224MC, and that was a success, first time I could image details on Neptune with my backyard telescope (probably 2 spots):

n20150720i-02h32.5UT-MDe.jpg

 

That camera works quite well in infrared, I even imaged the faint Neptune with the same magnification as I use on Jupiter or Saturn!

I could update the ephemeris for the brightest spot transit:

WinJUPOS 10.2.0 (Neptune), C.M. transit times, 2015/07/20  18:31
Object longitude: L = 222,4° + 23,3313°/d * (T - 2015 Jul 16,5)
Time interval: 2015 Jul 12,0 ... 2015 Sep 01,0
Output format: Date UT (C.M. of System 1)
------------------------------------------------------------------------------
2015 Jul 12   09:49 ( 127°)
2015 Jul 13   02:39 ( 143°)   19:29 ( 160°)   19:30 ( 160°)
2015 Jul 14   12:20 ( 176°)
2015 Jul 15   05:10 ( 192°)   22:01 ( 209°)
2015 Jul 16   14:51 ( 225°)
2015 Jul 17   07:42 ( 242°)
2015 Jul 18   00:32 ( 258°)   17:23 ( 274°)
2015 Jul 19   10:13 ( 291°)
2015 Jul 20   03:04 ( 307°)   19:54 ( 323°)
2015 Jul 21   12:44 ( 340°)   12:45 ( 340°)
2015 Jul 22   05:35 ( 356°)   22:25 (  12°)
2015 Jul 23   15:16 (  29°)
2015 Jul 24   08:06 (  45°)
2015 Jul 25   00:57 (  62°)   17:47 (  78°)
2015 Jul 26   10:38 (  94°)
2015 Jul 27   03:28 ( 111°)   20:19 ( 127°)
2015 Jul 28   13:09 ( 143°)
2015 Jul 29   05:59 ( 160°)   06:00 ( 160°)   22:50 ( 176°)
2015 Jul 30   15:40 ( 192°)
2015 Jul 31   08:31 ( 209°)
2015 Aug 01   01:21 ( 225°)   18:12 ( 242°)
2015 Aug 02   11:02 ( 258°)
2015 Aug 03   03:53 ( 275°)   20:43 ( 291°)
2015 Aug 04   13:34 ( 307°)
2015 Aug 05   06:24 ( 324°)   23:15 ( 340°)
2015 Aug 06   16:05 ( 356°)
2015 Aug 07   08:56 (  13°)
2015 Aug 08   01:46 (  29°)   18:36 (  45°)   18:37 (  46°)
2015 Aug 09   11:27 (  62°)
2015 Aug 10   04:17 (  78°)   21:08 (  95°)
2015 Aug 11   13:58 ( 111°)
2015 Aug 12   06:49 ( 127°)   23:39 ( 144°)
2015 Aug 13   16:30 ( 160°)
2015 Aug 14   09:20 ( 176°)
2015 Aug 15   02:11 ( 193°)   19:01 ( 209°)
2015 Aug 16   11:52 ( 226°)
2015 Aug 17   04:42 ( 242°)   21:33 ( 258°)
2015 Aug 18   14:23 ( 275°)
2015 Aug 19   07:14 ( 291°)
2015 Aug 20   00:04 ( 307°)   16:55 ( 324°)
2015 Aug 21   09:45 ( 340°)
2015 Aug 22   02:36 ( 357°)   19:26 (  13°)
2015 Aug 23   12:17 (  29°)
2015 Aug 24   05:07 (  46°)   21:58 (  62°)
2015 Aug 25   14:48 (  78°)
2015 Aug 26   07:38 (  95°)   07:39 (  95°)
2015 Aug 27   00:29 ( 111°)   17:19 ( 127°)   17:20 ( 128°)
2015 Aug 28   10:10 ( 144°)
2015 Aug 29   03:00 ( 160°)   03:01 ( 160°)   19:51 ( 177°)
2015 Aug 30   12:41 ( 193°)   12:42 ( 193°)
2015 Aug 31   05:32 ( 209°)   22:22 ( 226°)   22:23 ( 226°)
------------------------------------------------------------------------------

Good luck!


Edited by Marc Delcroix, 20 July 2015 - 02:13 PM.


#2 Gabor Kiss

Gabor Kiss

    Mariner 2

  • -----
  • Posts: 222
  • Joined: 20 Jun 2013

Posted 20 July 2015 - 03:13 PM

Excellent image! Thanks for posting!



#3 phileefan

phileefan

    Viking 1

  • *****
  • Posts: 971
  • Joined: 13 Nov 2013

Posted 20 July 2015 - 03:30 PM

Marc,

 

Very cool image! Thanks for sharing. Clear skies......  :waytogo:



#4 Kokatha man

Kokatha man

    Hubble

  • *****
  • Posts: 15,954
  • Joined: 13 Sep 2009

Posted 20 July 2015 - 09:10 PM

Excellent Marc!!!

You beat us on this one - congratulations! ;)

We were out imaging Neptune & Uranus with the 224 yesterday morning - I'm still to process the Neptune images properly, it is actually the first time we have imaged Neptune...but we caught banding & polar brightening on Uranus as well as Ariel & Umbriel...15 millisecond exposures!!!

As you know the iR response for the red without any filters* made us think that it would be worthwhile imaging these planets with this camera - & even the green's response is pretty reasonable...

This camera is quite literally incredible - we imaged Neptune at 33FPS & Uranus at 54FPS...amazing rates!!! :)

Excellent work, keep it up! :)

Imagine when we can have a mono camera with this sort of sensitivity & response!!!!!

*I realise you have used a 685nm filter with the camera - we didn't use any but will probably experiment with the filters the next time we can image. :)

Edited by Kokatha man, 20 July 2015 - 09:12 PM.


#5 Sunspot

Sunspot

    Voyager 1

  • *****
  • Posts: 10,361
  • Joined: 15 Mar 2005

Posted 20 July 2015 - 09:16 PM

Excellent Marc!!!

You beat us on this one - congratulations! ;)

We were out imaging Neptune & Uranus with the 224 yesterday morning - I'm still to process the Neptune images properly, it is actually the first time we have imaged Neptune...but we caught banding & polar brightening on Uranus as well as Ariel & Umbriel...15 millisecond exposures!!!

As you know the iR response for the red without any filters made us think that it would be worthwhile imaging these planets with this camera - & even the green's response is pretty reasonable...

This camera is quite literally incredible - we imaged Neptune at 33FPS & Uranus at 54FPS...amazing rates!!! :)

Excellent work, keep it up! :)

Imagine when we can have a mono camera with this sort of sensitivity & response!!!!!

  :4   :gaah:



#6 Eltanin

Eltanin

    Vostok 1

  • -----
  • Posts: 130
  • Joined: 22 May 2011

Posted 20 July 2015 - 09:40 PM

Excelent! And the predictions too!

Thanks Marc!  :waytogo:  :waytogo:  :waytogo:  :waytogo:

 

My trial image, is a very crude one, used a SCT 11", with the Grasshopper USB3 camera - same Sony IMX174 chip as the ASI174, with far worst IR sensitivity than yours, so I uses the Baader 610 nm filter.

 

Tough target, and the climate is not helping either, so I´m very skeptical on my results.

My "spot" is in the wrong hemisphere, or I nixed things up in WinJupos... :p

 

Anyway, I´ll keep trying (there is a ASI224 on my way too)...

 

BTW, WinJupos does not show Triton, which make things a little harder still...

 

 

Attached Thumbnails

  • 2015-07-20-0731_2-AGEa_001.png


#7 Eltanin

Eltanin

    Vostok 1

  • -----
  • Posts: 130
  • Joined: 22 May 2011

Posted 20 July 2015 - 09:43 PM

Excellent Marc!!!

You beat us on this one - congratulations! ;)

We were out imaging Neptune & Uranus with the 224 yesterday morning - I'm still to process the Neptune images properly, it is actually the first time we have imaged Neptune...but we caught banding & polar brightening on Uranus as well as Ariel & Umbriel...15 millisecond exposures!!!

As you know the iR response for the red without any filters* made us think that it would be worthwhile imaging these planets with this camera - & even the green's response is pretty reasonable...

This camera is quite literally incredible - we imaged Neptune at 33FPS & Uranus at 54FPS...amazing rates!!! :)

Excellent work, keep it up! :)

Imagine when we can have a mono camera with this sort of sensitivity & response!!!!!

*I realise you have used a 685nm filter with the camera - we didn't use any but will probably experiment with the filters the next time we can image. :)

Awww, man! 33 fps?!!! Mine here, with the Grasshopper was 15 MINUTES to get 2000 frames... You KILL me! 



#8 John_K

John_K

    Viking 1

  • -----
  • Posts: 789
  • Joined: 28 Apr 2005

Posted 20 July 2015 - 10:29 PM

Excellent image Marc - looks like the 224 camera is delivering - cannot believe the FPS rates that you and Darryl are getting.

 

Yes, we need a mono version of this camera before the next Mars opposition next year!



#9 Marc Delcroix

Marc Delcroix

    Viking 1

  • -----
  • topic starter
  • Posts: 543
  • Joined: 26 Aug 2007

Posted 21 July 2015 - 02:56 AM

Excelent! And the predictions too!

Thanks Marc!  :waytogo:  :waytogo:  :waytogo:  :waytogo:

 

My trial image, is a very crude one, used a SCT 11", with the Grasshopper USB3 camera - same Sony IMX174 chip as the ASI174, with far worst IR sensitivity than yours, so I uses the Baader 610 nm filter.

 

Tough target, and the climate is not helping either, so I´m very skeptical on my results.

My "spot" is in the wrong hemisphere, or I nixed things up in WinJupos... :p

 

Anyway, I´ll keep trying (there is a ASI224 on my way too)...

 

BTW, WinJupos does not show Triton, which make things a little harder still...

Thanks!

Nice image, what is the date/time (UT) of acquisition (mid point) ? I'll check then...

Winjupos does not show Triton, right, I've been asking Grischa to add this (in the measures and in the ephemeris) since 2 years, hopefully he will sometime find the time to do it ...



#10 Marc Delcroix

Marc Delcroix

    Viking 1

  • -----
  • topic starter
  • Posts: 543
  • Joined: 26 Aug 2007

Posted 21 July 2015 - 03:01 AM

Excellent Marc!!!

You beat us on this one - congratulations! ;)

We were out imaging Neptune & Uranus with the 224 yesterday morning - I'm still to process the Neptune images properly, it is actually the first time we have imaged Neptune...but we caught banding & polar brightening on Uranus as well as Ariel & Umbriel...15 millisecond exposures!!!

As you know the iR response for the red without any filters* made us think that it would be worthwhile imaging these planets with this camera - & even the green's response is pretty reasonable...

This camera is quite literally incredible - we imaged Neptune at 33FPS & Uranus at 54FPS...amazing rates!!! :)

Excellent work, keep it up! :)

Imagine when we can have a mono camera with this sort of sensitivity & response!!!!!

*I realise you have used a 685nm filter with the camera - we didn't use any but will probably experiment with the filters the next time we can image. :)

Thanks Darryl.

 

I'm glad I could beat you at least once, I never thought it could happen :)

I do not understand how you get these framerates: I use a 320mm compared to your 354mm, and I imaged Neptune between 250ms/300ms exposures at a high magnification (with gain 400). What were your parameters and magnification/sampling scale ?

 

In the past I used a R610nm filter, but with that sensitivity I think it is worthwhile to image with a pure IR filter which increases the contrast of the spots.



#11 Marc Delcroix

Marc Delcroix

    Viking 1

  • -----
  • topic starter
  • Posts: 543
  • Joined: 26 Aug 2007

Posted 21 July 2015 - 03:37 AM

PS: Actually I realized on my side the very high sensitivity of all color channels in infrared, this is the reason why I am testing that cam. I thought beforehand it could have a strong interest for Jupiter/Saturn methane absorption band imaging, and Saturn / Uranus and Neptune infrared imaging ... which for what I could do in my first tests proves true ...



#12 Kokatha man

Kokatha man

    Hubble

  • *****
  • Posts: 15,954
  • Joined: 13 Sep 2009

Posted 21 July 2015 - 04:46 AM

 

 

I do not understand how you get these framerates: I use a 320mm compared to your 354mm, and I imaged Neptune between 250ms/300ms exposures at a high magnification (with gain 400). What were your parameters and magnification/sampling scale ?

 

In the past I used a R610nm filter, but with that sensitivity I think it is worthwhile to image with a pure IR filter which increases the contrast of the spots.

 

 

Hi again Marc - oh boy, you want me to calculate arcsecs/pixel..?!? I'm a klutz at those things - remember I'm just a "nuts & bolts" man!!! :lol:

 

Leaving aside what is said in the FC .txt below, & considering the f/l to be about 5300mm (courtesy of Torsten's advice re actual versus FC log values for the 224) with this camera's 3.75 pixel-sized sensor, my maths gives me about 0.14"/pixel as the acquisition value.....I think that's the correct figure...? :confused:

 

Remember, I'm not using any filters with only the AR window in front of the sensor which has a very wide band-pass from just above 300nm to way beyond 1000nm...also I didn't have any of our last year's Uranus capture details with us as a reference for setting the histograms...we used identical f/l's for Neptune & Uranus.

 

We're back home now & according to my FC .txt files from last year's Uranus we were using much greater f/l's previously - but it doesn't look like it from the images, & the 120 & 224 do have identical pixel-sized sensors!?! :confused:

 

The histogram settings for Uranus look fairly similar however...here's a .txt from last year & one from the other morning, ASI120MM-S & ASI224MC respectively - the 224 f/l is about 5300mm according to Torsten's advice, because the 224's pixel-sizing is not recorded in FC it presumes a default of 6uM.

 

However, I am really sceptical as to whether last year's f/l's with the ASI120MM-S are accurate..! :confused:

 

As I said above I should be trying out filters in front of the Bayer matrix sensor as per your 685nm image here - once again a fantastic result!!! :waytogo:  :waytogo:  :waytogo:  

 

.....it was really our first attempt at Neptune & just finding it was for us an achievement - but I'll relate that & additional information in my own thread when I post some images tomorrow. :grin:

 

UranusLogs.png

 

Addendum: just saw your last post before posting this - exactly our thoughts re Uranus & Neptune specifically!

 

Also, in the 224 .txt we paused the capture for defogging the corrector plate at one stage...

 

Finally, those f/l's for the ASI120MM-S are definitely incorrect - I looked at another night's capture with that camera where we used the same imaging train - & FC gives 40,390mm..!!!  ;)

 

Looking at the WMP playbacks the image scales look fairly similar...


Edited by Kokatha man, 21 July 2015 - 05:02 AM.


#13 John Boudreau

John Boudreau

    Vanguard

  • *****
  • Posts: 2,052
  • Joined: 06 Apr 2008

Posted 21 July 2015 - 06:54 AM

Excellent work Marc! I also hope to get some good conditions to start monitoring Neptune soon.

 



Winjupos does not show Triton, right, I've been asking Grischa to add this (in the measures and in the ephemeris) since 2 years, hopefully he will sometime find the time to do it ...

 

Grischa has mentioned to me in the past that the available satellite ephemeris for Neptune is too large for WinJupos. He apparently uses this site as a source, so you can check the huge Neptune files in comparison to the other planets. I wonder if this has to do with Triton's retrograde orbit?:

 ftp://ftp.imcce.fr/pub/ephem/satel/

 

Currently I use this for Triton. Certainly not a convienient as WinJupos:

http://new-pds-rings...iewer2_nep.html



#14 Marc Delcroix

Marc Delcroix

    Viking 1

  • -----
  • topic starter
  • Posts: 543
  • Joined: 26 Aug 2007

Posted 21 July 2015 - 07:12 AM

Thanks for the info Darryl - understood, short exposures due to no filter, sound more coherent for me.

As for the plate scale, 0.14 arcsec/pixel sounds OK to me, although I would personally with a 14 inches go down to 0.1 arcsec/pixel.

 

The IMX224 sensor has a well depth 4 times lower than the ASI174MM, so I thought that I should increase a bit the histogram (38% as in your FC log is a bit low ?), what do you think ?

 

Thanks John - Grischa did not give me that explanation, I know understand why it goes down in the queue. I also use NASA's Neptune viewer, but for the measures it's really a long process to make use of it ... and I'm expecting more and more Neptune's images to be measured !



#15 John Boudreau

John Boudreau

    Vanguard

  • *****
  • Posts: 2,052
  • Joined: 06 Apr 2008

Posted 21 July 2015 - 07:24 AM

PS: Actually I realized on my side the very high sensitivity of all color channels in infrared, this is the reason why I am testing that cam. I thought beforehand it could have a strong interest for Jupiter/Saturn methane absorption band imaging, and Saturn / Uranus and Neptune infrared imaging ... which for what I could do in my first tests proves true ...

 

Yes, the ASI224MC can certainly give a clean looking near-IR result, but sadly misses much of the deep red/near-IR out to ~800nm due to low sensitivity in the G and B in that region--- right where we'd pick up the best resolution of these bright spots and other features for Neptune and Uranus. Because of this, although I plan on using the cooled version as my main camera I won't be using it for Mercury. It's still an incredible camera and may well be the best all-around camera available, but I hope that some machine and/or security market appears to entice Sony to produce a monochrome version of that sensor.



#16 Tbob32

Tbob32

    Explorer 1

  • -----
  • Posts: 53
  • Joined: 21 Mar 2014

Posted 21 July 2015 - 08:44 AM

Great shot. That is one of my goals over the next year, to image all of the planets. 



#17 Kokatha man

Kokatha man

    Hubble

  • *****
  • Posts: 15,954
  • Joined: 13 Sep 2009

Posted 21 July 2015 - 08:59 AM

Thanks for the info Darryl - understood, short exposures due to no filter, sound more coherent for me.

As for the plate scale, 0.14 arcsec/pixel sounds OK to me, although I would personally with a 14 inches go down to 0.1 arcsec/pixel.

 

The IMX224 sensor has a well depth 4 times lower than the ASI174MM, so I thought that I should increase a bit the histogram (38% as in your FC log is a bit low ?), what do you think ?

 

Thanks John - Grischa did not give me that explanation, I know understand why it goes down in the queue. I also use NASA's Neptune viewer, but for the measures it's really a long process to make use of it ... and I'm expecting more and more Neptune's images to be measured !

 

Yes - I agree that the f/l should be a bit longer Marc, increasing the value down to 0.1"/pxl or thereabouts...I have a bit of an issue with adapters atm due to trying to run the 224 & 174 as interchangeable setups...

 

We had good outcomes with the ASI120MM-S last year with similar histograms but I was planning on using the 174 for the reason you intimate above...I thought that similarly to our Saturns this year I could get a good tonal/contrast range with lower histograms for Uranus using the 174MM because of WD as per Karel's comments thereon. (& thus possibly higher FPS or a bit more image scale)

 

I really only wanted to try the 224 on Uranus & Neptune for the same reason you thought it worthwhile...unfortunately our Neptune images from the other morning don't appear to yield anything worthwhile although we did get polar brightening & faint "banding" as well as Ariel & Umbriel with Uranus - this with no filter...which I think at least vindicates both our thoughts as to the camera's possible merits therein...

 

I will try with iR filters in our next sessions (like Almir the weather is pretty bad here in general atm) & I also think John makes some valid points...but your results here (& to a much lesser extent our completely unfiltered Uranus image) also suggest this camera "brings something to the table" in imaging these 2 planets.....when our turret assembly is up & running we hope to have more flexibility again...& now I know where to find Neptune we aren't intimidated by that problem anymore - not employing "Go To" or any other refined targeting...& with a "rough & ready" PA out in the field I was about to give up in the freezing conditions when Pat exclaimed "there it is!!!" as I scanned the field, crouched underneath the finder-scope while she watched the laptop screen!!! ;)



#18 Sunspot

Sunspot

    Voyager 1

  • *****
  • Posts: 10,361
  • Joined: 15 Mar 2005

Posted 21 July 2015 - 09:22 AM

 

Excelent! And the predictions too!

Thanks Marc!  :waytogo:  :waytogo:  :waytogo:  :waytogo:

 

My trial image, is a very crude one, used a SCT 11", with the Grasshopper USB3 camera - same Sony IMX174 chip as the ASI174, with far worst IR sensitivity than yours, so I uses the Baader 610 nm filter.

 

Tough target, and the climate is not helping either, so I´m very skeptical on my results.

My "spot" is in the wrong hemisphere, or I nixed things up in WinJupos... :p

 

Anyway, I´ll keep trying (there is a ASI224 on my way too)...

 

BTW, WinJupos does not show Triton, which make things a little harder still...

Thanks!

Nice image, what is the date/time (UT) of acquisition (mid point) ? I'll check then...

Winjupos does not show Triton, right, I've been asking Grischa to add this (in the measures and in the ephemeris) since 2 years, hopefully he will sometime find the time to do it ...

 

I remember Grischa commenting that the ephemeris for Triton is extremely complex which is why he hasn't put it into WJ. Would be nice though...



#19 sfugardi

sfugardi

    Skylab

  • *****
  • Posts: 4,018
  • Joined: 30 Sep 2006

Posted 21 July 2015 - 12:03 PM

Marc, impressive capture! Congratulations on the image result and thanks for sharing it

 

Regards,

Steve



#20 Eltanin

Eltanin

    Vostok 1

  • -----
  • Posts: 130
  • Joined: 22 May 2011

Posted 21 July 2015 - 06:14 PM

 

Excelent! And the predictions too!

Thanks Marc!  :waytogo:  :waytogo:  :waytogo:  :waytogo:

 

My trial image, is a very crude one, used a SCT 11", with the Grasshopper USB3 camera - same Sony IMX174 chip as the ASI174, with far worst IR sensitivity than yours, so I uses the Baader 610 nm filter.

 

Tough target, and the climate is not helping either, so I´m very skeptical on my results.

My "spot" is in the wrong hemisphere, or I nixed things up in WinJupos... :p

 

Anyway, I´ll keep trying (there is a ASI224 on my way too)...

 

BTW, WinJupos does not show Triton, which make things a little harder still...

Thanks!

Nice image, what is the date/time (UT) of acquisition (mid point) ? I'll check then...

Winjupos does not show Triton, right, I've been asking Grischa to add this (in the measures and in the ephemeris) since 2 years, hopefully he will sometime find the time to do it ...

 

Thank you, but it is grainy as hell...  :p  

 

Nothing even close to yours!  :bow:

 

ASI174 demanded 2 fps at 284.8 ms just to get Triton in the frame... 15 minutes each one of the three 2000 frames videos

 

The midpoint of the derotaded image is 2015-07-20 07:31.2 (each frame at 7:23.4, 7:35.1 and 7:51.1)



#21 mak5

mak5

    Messenger

  • -----
  • Posts: 437
  • Joined: 09 Mar 2009

Posted 21 July 2015 - 10:23 PM

Very nice images, Marc, now you made Neptune a lot interesting to image. I hope to get the spot this Saturday if all goes well, no visibility yet from my site.

#22 Marc Delcroix

Marc Delcroix

    Viking 1

  • -----
  • topic starter
  • Posts: 543
  • Joined: 26 Aug 2007

Posted 22 July 2015 - 12:22 AM


...& now I know where to find Neptune we aren't intimidated by that problem anymore - not employing "Go To" or any other refined targeting...& with a "rough & ready" PA out in the field I was about to give up in the freezing conditions when Pat exclaimed "there it is!!!" as I scanned the field, crouched underneath the finder-scope while she watched the laptop screen!!! ;)

 

... I know what it is, I image with a Dobson on a equatorial platform with a telrad, with no goto, under a suburbian sky...

but I found Neptune not that difficult to find with star hopping (especially since my town decided to turn the light off between 1:00 end 5:30 am.

Uranus I could not do in 10 minutes, it's lost in the Pisces among faint stars ...

 

But that's also a small pleasure to do this "manually" ...



#23 Kokatha man

Kokatha man

    Hubble

  • *****
  • Posts: 15,954
  • Joined: 13 Sep 2009

Posted 22 July 2015 - 02:37 AM

...& now I know where to find Neptune we aren't intimidated by that problem anymore - not employing "Go To" or any other refined targeting...& with a "rough & ready" PA out in the field I was about to give up in the freezing conditions when Pat exclaimed "there it is!!!" as I scanned the field, crouched underneath the finder-scope while she watched the laptop screen!!! ;)

... I know what it is, I image with a Dobson on a equatorial platform with a telrad, with no goto, under a suburbian sky...
but I found Neptune not that difficult to find with star hopping (especially since my town decided to turn the light off between 1:00 end 5:30 am.
Uranus I could not do in 10 minutes, it's lost in the Pisces among faint stars ...
 
But that's also a small pleasure to do this "manually" ...


I agree that there is a "small pleasure" or "reward" in locating these planets without more sophisticated software Marc, & you EQ platform is another step harder than our scenario...

I have no problem nailing Uranus, I hit it straight away after almost a year's absence...but this is in dark skies & I can actually see Uranus with my eyes & averted vision in the Murray Mallee!

Pat (who watches the laptop screen whilst I contort myself under the finder-scope moving the mount & checking various stars in the FOV - I really must put a right-angled finder on the C14!) has her own take on identifying a planet from a star when the exposure is as high as it is when we search - she tells me that planets don't have any "bling" around them!!! :lol:

She is correct btw...there is a sparkle of "snow" around the over-exposed stars - but not so Uranus or Neptune! :)

#24 Marc Delcroix

Marc Delcroix

    Viking 1

  • -----
  • topic starter
  • Posts: 543
  • Joined: 26 Aug 2007

Posted 22 July 2015 - 08:42 AM

 

She is correct btw...there is a sparkle of "snow" around the over-exposed stars - but not so Uranus or Neptune! :)

 

 

Women are always correct ;) In that case that could be a view of turbulence on "speckles" (air cells in the atmosphere), that's visible at high resolution with large diameter on pinpoint stars, and is not visible on objects with apparent diameter like planets, even small Neptune ...

 

I personally like to do the pointing on the eyepiece, an excuse to really look at our lovely planets ;)




CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.


Recent Topics






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics