Software that does meridian flips

[gregbradley]

I am finding too often the need to do a meridian flip keeps me up at night when imaging or I am missing out on a few extra hours of imaging because it needs to be done in the middle of the night.

I am using a Planewave CDK17, PME and SBIG Sti guider.

I just did a 330 point T-point model so accurate go-tos are working (target almost in dead centre of the frame - amazing really when its 3 metres of focal length).

What software is good for this? I am not looking to do full automation as this is at my home observatory. I may want to add a refocus routine as well but the CDK tends not to change focus through the night much.

Greg.

[RickS]

Greg,

ACP handles all this very well but may be more than you want or need. I tried several alternatives but it was the one that gelled for me.

CCD Autopilot, CCD Commander and Sequence Generator Pro are all probably worth considering too.

Cheers,
Rick.

[DavidTrap]

I've had good results with CCD Commander. Meridian flips work well, depending on how orthogonal your OTA is - although a T-point model might negate that.

CCDC does a plate-solve and resync after a meridian flip (although you could turn that off if you wish). I've left it run overnight unattended with a 600mm focal length, but it often needs a bit of supervision with my 1800mm scope - this is on a temporary setup with no pointing model.

Once you've used scripted imaging, you won't go back to manual. It can click the buttons, slew to a focus star, refocus, slew back to your target, start imaging again with a new filter, park and the end of the night, wake itself up when it needs to take dawn flats, etc, etc, far more efficiently than you can!

Even when I'm up at Leyburn, I still run a script so that I can wander around and chat, watch a DVD or catch some Zzzzzzs.

DT

[marc4darkskies]

+1 for CCDAutopilot - it does the lot.

Cheers, Marcus

[allan gould]

SG Proo does a meridian flip with ease and back on target to within a few pixels even with a EQ6 mount. Quite cheap but fully functional.

[gregbradley]

Some great advice here. Thanks for the replies. I'll have to get some software installed and start using that as I am missing out on too much data when the mount hits the tracking limits.

Greg.

[Hans Tucker]

Buy a Chronos Mount.

http://www.chronosmount.com/ :D

[lazjen]

Ack, price. :eyepop: Looks good though. :)

[gregbradley]

$50G's for a mount! Wow, who are they selling to?

I doubt it would outperform the PME for 1/4 the price except for the meridian flip aspect.

Speaking of that is it possible to change the software limits for the PME so it goes 1 or 2 hours past the meridian like the PMX will?

Greg.

[naskies]

My poor man's version is to do an inverted flip as early as I can, and set the mount to park on horizon limit. For in-season targets that transit around midnight, I can go to bed at a reasonable hour (10 pm) and still get a full night's worth of data in.

[gregbradley]

That's a good idea. I am not sure if the PME will let me do that though. I'll have to experiment with the software limits.

There are a ton of pretty galaxies, all quite small and dim though, near Acamar and below Sculptor. So that means for me where east is where the light pollution is I need to start imaging them around midnight +.

Greg.

[rogerg]

+1 for ccdcommander.

the only thing I make sure of is that the maximum exposure time is less than the amount of time the PME will guide past the meridian. I set the meridian limit to zero such that I can comfortably fit in 10 minute exposure times. It checks the meridian position at the start of taking each image.

[Joshua Bunn]

I guess you can change the software limits, but the PME has physical hard stops just after the mount has gone through the zenith that cant be changed. Give it a try, disengage the worms and slowly rotate the RA axis slowly past the zenith, you will hit a stop and thats as far as it will go.

Josh

[jase]

+1 for ACP (http://acp.dc3.com) (and +1 for ACP Scheduler (http://scheduler.dc3.com/) - there is no better combination for maximising imaging time).

I don't think there is automation software on the market that doesn't handle a meridian flip. If thats all you are looking for, take your pick. Its not a complex task, even with a rotator flipping 180 degrees so you pick up the same guide star in the OAG - all basic stuff.

I used CCDAP in a remote operation for a few months. I like the simplicity in particular the sky flat routine. It drastically needs a web interface so that you can remotely control the observatory on absolutely any device. Very handy with a remote set up. ACP continues to be ahead of time and highly customisable, some would say too customisable but then there is a need for such flexibility. Take a look around at the rental scope market (itelescope, lightbuckets, etc), and many universities, they'll all be running ACP.

[gregbradley]

Thanks for the good advice. I'll check out ACP and CCD Commander as well.

Greg.

[alistairsam]

Hi

I know this software below isn't specific to meridian flips, but this is an automation software that can do pretty much everything including dome control, and best of all, its free.

I was pretty impressed with all the features and it does automated meridian flips, dome closure, focus, g2v, auto centering and a lot of other stuff.

The website is in french but the software has english.
The control panel is like an aircraft cockpit with so many options, I think its worth a whirl.

of course support isn't that great like the other mainstream software, but looks like there's a lot of work gone into it.

here's the CN thread on it
http://www.cloudynights.com/ubbthreads/showflat.php/Cat/0/Number/5169793/page/0/view/collapsed/sb/5/o/all/fpart/1/vc/1

http://www.felopaul.com/software.htm

only downside is it needs thesky or pinpoint for plate solves. if it could have used Elbrus, would've been perfect as it works with CDC.

so handy for people like me who just wants to load a target list in the evening, and let it take care of things.

Cheers
Alistair

[alistairsam]

looks like it can also do skyflats based on a target adu at a specific time, all automated.

[White Rabbit]

Interesting. I'm looking at going down the automation route but dont really want to spend $300 for CCDAP when all I really want is meridian flip and perhaps slew to a couple of targets during a session.
The basic version of CCD at $100 does all I need but you need to have the full version as the basic doesnt support TSX camera addon. WTF!!! That really pissed me off.

I cant seem to find the cost of the software you linked to in your post above, whats the cost?

Thanks

[alistairsam]

Its free. That's the best bit!!

Alistair

[alistairsam]

Hi,

CCD commander does it all as well and that's $100. so does sequence gen pro.
the key to all this automation is plate solves. I've been struggling with plate solves in maxim recently, when it was working fine for me sometime back.
a few others have issues with plate solves in theskyx, but other times it works. so i don't think there's a guarantee unless your setup is fully permanent, very well polar aligned, several sync points etc where the plate solve just works every time.
key to the meridian flip is the solve and center after the flip.

but this maxpilote seems to do it all and for free. yet to try it out.

Cheers
Alistair

[White Rabbit]

Very interesting, I've downloaded it so I'll give it a spin fist chance I get.

Thanks for posting the link.

[White Rabbit]

Well, I'm somewhat speechless regarding this Maxpointe software.

I downloaded it last night and had a bit of a poke about (not connected to the mount or cameras) and it does just about (just about) everything that CCDAP basic does and a bit more and it's free. Best of all it will use PHD for guiding, I get much better results with PHD and I get to back to my Meade DSI II for guiding and I can get rid of that **** SSAG. I swear that is the noisiest camera in the world.
I've just spent that last hour reading through the three page thread over at Cloudy nights, and author, Laurent has done a bang up job with supporting this free software. It's quite astounding.
In some cases people are asking "hey it would be cool if you could implement xyz feature" and the next post he's offering an update day "done".

Quite amazing. If it works they way it's advertised, he'll be getting the money I would have spent on CCDAP.

Thanks

[multiweb]

I use Cirque du Soleil v1.3. :juggle:

[alistairsam]

my thoughts as well. very good effort from one individual.
how will you be plate solving though
it uses skyx or pinpoint.
wish it could use elbrus.

Alistair

[White Rabbit]

I have TSX and the camera add on so no problem there. Tomorrow should be a clear night so I'll get out and give it a go.

[RobF]

Must check out Maxpilote.
Have had a couple of tries at SGP but laptop problems were a higher priority to sort. My last few outings have been very manual, which gets tedious - New Year's Resolution - must get automation back up to speed!

[naskies]

It seems that there are many good options available :thumbsup:

Does anyone with a backlash-prone mount, such as an EQ6, have experience with automation software?

[DavidTrap]

You shouldd talk to Mark Lewis first Dave - he's pretty happy with the lack of backlash after installing belts on his EQ6. Might make the automation task easier. I'm happy to show you through CCDC at Leyburn some time.

DT

[alistairsam]

hi

automation relies on plate solving and it should work fine provided your PA is good and you have atleast 4 or 5 sync points.
errors due to backlash does add up when you slew a lot, but should be within the plate solve engine's search field.

Once my PA is as close as I can get, I slew to a known star, loosen the clutches, center manually, then park. reset power and the next slew is very close even without a sync point. i then sync atleast 5 stars.
after that, plate solves in maxim work straight away either side of the meridian. so no reason why other automation software wouldn't be able to auto center your target.

I've had decent results with SGP and Elbrus, and am trying out pinpoint with the USNO-A2.0 catalog.
this would then work with a variety of automation software.

once crucial bit is the side of pier reporting. I believe eqascom has a fix for it? not sure if its included in the latest version. so if that's relayed correctly to your software, centering targets after a flip would work without issues.

cheers
Alistair

[naskies]

Thanks David. I think I'll have to try the belt mod out over the summer - I'm still waiting for the no-mechanical-mods-required kit from the UK, but it sounds like Mark's mod only requires minimal filing.

Yes, I'm keen to see how you have CCDC set up.



Thanks for that Alistair. Yes, I've been using plate solving in MaximDL to centre targets and an N-point model in EQMOD usually does a good job of landing me very close anywhere in the sky (close enough to plate solve with PinPoint).

The problem is that even with iterative plate solving and re-centering, I can sometimes still be up to 30'' off-centre due to backlash. This wouldn't be a problem if I were imaging wide fields, but with a 38' x 28' FOV and native 0.67''/pixel, imaging on both sides of the meridian, across multiple nights, and with dithering enabled... I find that accurate re-centering is important, otherwise I can lose huge amounts off the edges after stacking (from experience).

I think applying the belt mod to eliminate backlash will be the best way ahead.

[alistairsam]

found this very interesting discussion on issues with meridian flip using ccdcommander, specific to autoguide failure after the flip.

It covers issues and settings in maxim dl, ccdsoft, and direct guiding with paramount mounts etc.
64 post discussion. worth a read.

http://groups.yahoo.com/neo/groups/CCDCommander/conversations/topics/10163

Cheers
Alistair

[RobF]

You can tell CCDC to keep recentering and solving until within a certain error, but backlash is tricky. I suppose you could slew to one side of the object, then solve to get your gear/worm on one side of its backlash possibly? I guess once you start doing iterative solves you'll be back at the mercy of the backlash again though.

PMX is the answer Dave!?