Planet positions and imaging with C11 XLT + Neximage 5.

[WicklowSkies76]

Hi there. I am based in Ireland so my Latitude is 53 degrees North.

I recently purchased a used C11 XLT and it came with a Neximage 5 for planetary imaging. I am planning on trying to image Jupiter and Saturn over the coming nights but still wrestling with the setup and GoTo features of the mount (AZEQ6 GT). I have a bit of a niggling feeling before getting started that I am going to be disappointed with the quality of the image I can capture due to the low position of the planets relative to the horizon. I also read somewhere that the planets are going to be like this for the next decade or so... is this true? If so, I feel I may have made the wrong decision in opting for such a powerful scope to focus on Planetary imaging as it's possibly going to be overkill and the seeing will limit the image quality based on planetary positions. You see I had the option of going for an 8" Edge HD for a similar price but opted for the C11 instead. Is it true that planetary imagers in UK/Ireland are in for a bad stretch?

[Cosmic Geoff]

To answer your last question, there has been some discussion about this on the forum, and in particular I remember a graph which shows the altitudes at transit for the next few years - Mars & Jupiter improve rapidly, Saturn more slowly.

An ADC (atmospheric dispersion corrector) will counteract some of the malign effects of the low altitude.  A C11 will probably do fine, and you've got it now ... some suggest that a C9.25 is the sweet spot for lousy UK conditions, but some members here post fine pics taken with C14's. 

Seeing is key, and if you are in a rural location with vegetation under the light path you may have better luck than those in urban locations.

As for your mount, it is perfectly possible to planet image with an Alt-az GoTo, (avoiding the hassle of polar alignment) and since you have the option, I suggest that you accurately level your tripod, set the mount in alt-az mode, and solar system align it on the planet you want to image.  That process ought to be quick and painless.   The only downside of using guided alt-az for this is that the image may be tilted (which may not bother you at all)  You may get less drift with a two-star align.  I presume that an AZEQ6 GT can do a two-star align in AZ mode - I don't have one so I wouldn't know.

[geoflewis]

Hi @WicklowSkies76 the planets are definitely not well placed this year, but it is still possible to get reasonable images in good seeing and your C11 is an excellent scope for that. Next year Mars will be pretty well placed at about 40 degrees altitude and almost as big (c 24") as it was last year, so that will definitely be a very worthwhile target. Jupiter and Saturn will also be starting to gain altitude albeit still at around 15 deg, with Saturn the slightly higher up of the two, but by 2021 Jupiter will be at 25 degrees and climbing rapidly the following few years.

As Geoff @Cosmic Geoff says, it is worth investing in an ADC and planetary imaging is perfectly OK using an altaz mount as you will be taking video of only 1-2 minutes duration, so not much sky rotation during that timeframe.

Good luck, I look forward to seeing you post some images. Practice now and you'll be ready for Mars next year.

Geof

[WicklowSkies76]

59 minutes ago, Cosmic Geoff said:

To answer your last question, there has been some discussion about this on the forum, and in particular I remember a graph which shows the altitudes at transit for the next few years - Mars & Jupiter improve rapidly, Saturn more slowly.

An ADC (atmospheric dispersion corrector) will counteract some of the malign effects of the low altitude.  A C11 will probably do fine, and you've got it now ... some suggest that a C9.25 is the sweet spot for lousy UK conditions, but some members here post fine pics taken with C14's. 

Seeing is key, and if you are in a rural location with vegetation under the light path you may have better luck than those in urban locations.

As for your mount, it is perfectly possible to planet image with an Alt-az GoTo, (avoiding the hassle of polar alignment) and since you have the option, I suggest that you accurately level your tripod, set the mount in alt-az mode, and solar system align it on the planet you want to image.  That process ought to be quick and painless.   The only downside of using guided alt-az for this is that the image may be tilted (which may not bother you at all)  You may get less drift with a two-star align.  I presume that an AZEQ6 GT can do a two-star align in AZ mode - I don't have one so I wouldn't know.

 

34 minutes ago, geoflewis said:

Hi @WicklowSkies76 the planets are definitely not well placed this year, but it is still possible to get reasonable images in good seeing and your C11 is an excellent scope for that. Next year Mars will be pretty well placed at about 40 degrees altitude and almost as big (c 24") as it was last year, so that will definitely be a very worthwhile target. Jupiter and Saturn will also be starting to gain altitude albeit still at around 15 deg, with Saturn the slightly higher up of the two, but by 2021 Jupiter will be at 25 degrees and climbing rapidly the following few years.

As Geoff @Cosmic Geoff says, it is worth investing in an ADC and planetary imaging is perfectly OK using an altaz mount as you will be taking video of only 1-2 minutes duration, so not much sky rotation during that timeframe.

Good luck, I look forward to seeing you post some images. Practice now and you'll be ready for Mars next year.

Geof

Thank you both - very reassuring and great info also. Huge thanks. I got the following links which will help me keep an eye on the altitudes for the moment.

https://in-the-sky.org//article.php?term=Saturn&skin=1

https://in-the-sky.org//article.php?term=Jupiter&skin=1

Regarding ditching the Polar Alignment, I have tried the mount in AltAz mode but wasn't sure how to do Solar System alignment. I might try that later because I don't know if my Polar scope is calibrated correctly and I don't want to waste a good nights seeing unnecessarily grappling with Polar Alignment.

Regarding the Solar System Align, is the general process there that you select a planet and then manually slew to that planet using your eye and then center, then confirm on the handset then do the same for another planet? Does the mount need to be in any particular position before you start? Wondering how the mount can get it's bearings in this mode without Polar Alignment...?

Edited July 3, 2019 by WicklowSkies76

[Cosmic Geoff]

19 minutes ago, WicklowSkies76 said:

Regarding the Solar System Align, is the general process there that you select a planet and then manually slew to that planet using your eye and then center, then confirm on the handset then do the same for another planet? Does the mount need to be in any particular position before you start? Wondering how the mount can get it's bearings in this mode without Polar Alignment...?

 With any Goto system, one celestial object is enough for alignment provided that the mount is accurately leveled. I can only speak for the Celestron version as regards how to go about it - start with mount leveled and scope pointed at random, enter date, time, location, select solar system object, traverse to it, coarse and fine align, job done! I suspect that the Synscan is not so simple, and you may have less of a fight with it if you start with it crudely indexed in a northerly direction. If in doubt, RTFM 🙂

[geoflewis]

36 minutes ago, WicklowSkies76 said:

Thank you both - very reassuring and great info also. Huge thanks. I got the following links which will help me keep an eye on the altitudes for the moment.

https://in-the-sky.org//article.php?term=Saturn&skin=1

https://in-the-sky.org//article.php?term=Jupiter&skin=1

Well they are 2 excellent resources that I've not seen previously, so thanks for those .

Geof