PHD2.6.9dev2 released

[Jonk]

I've just seen this on another site, but PHD2 latest dev build can now do multistar guiding.

They reckon an average of multiple stars yields a big improvement.

I'll try it out next time I can see stars!

Get it here -> https://openphdguiding.org/phd2-2.6.9dev2-installer.exe

• New: Multi-star guiding
• New: Moravian camera support
• Bug fix: ensure Dec comp is applied when meridian flip is accompanied by a Dec slew
• ZWO: update ZWO ASI SDK to version 1.16 - Windows, Linux, and Mac
• SBIG cameras: remember choice of whether to use the tracking CCD
• ZWO / INDI / ASCOM cameras: use binned frame size reported by camera
• ZWO camera: fix possible crash when changing binning
• INDI cameras: discard stale video frames when switching binning
• INDI cameras: improved verbose INDI logging
• Fix crash when cancelling AO port selection
• Fix crash when new profile created with mount set to None
• Fix incorrect pixel size change warning when new profile is created
• Updated French, Polish and Traditional Chinese translations

[sloz1664]

Cheers Jonk, Just downloaded it and hopefully I'll be able to try it out sometime this year 

Steve 

[Skipper Billy]

I used it for the first time last night - in poor seeing - it worked flawlessly and turning the multistar feature on and off revealed about a 10 - 15% improvement with it switched on.

The large green box is the primary star and the small green circles are the secondary support stars.

 

 

 

[sloz1664]

Thanks David, and guess what? The weather forecast for the next week looks woeful.

Steve

[fireballxl5]

I also had opportunity to try the new multi star option last night. Seeing was poor but thought that it performed better than it would have normally, giving more consistent guiding over the couple of hours that I was out.  Didn't think to try a with/without test though, just selected it from the off and it worked very well so very promising. 

[Freddie]

1 hour ago, Skipper Billy said:

I used it for the first time last night - in poor seeing - it worked flawlessly and turning the multistar feature on and off revealed about a 10 - 15% improvement with it switched on.

The large green box is the primary star and the small green circles are the secondary support stars.

 

 

 

10-15% as measured by what? I assume something like FWHM on the subs?

 

[Skipper Billy]

8 minutes ago, Freddie said:

10-15% as measured by what? I assume something like FWHM on the subs?

Total RMS - averaged about 0.5" over 30 mins without it on and about 0.4" with it on - not scientific but certainly noticeable.

[Freddie]

Thanks, so all your reporting is a reduced RMS when calculated for multi star Vs single, which does no necessarily mean you will see an improvement in the actual image. It may be the case that multi star averages out the seeing and allows for shorter guide exposures and ensures guide commands are only issued when really needed but all I'm seeing being reported is that the RMS improves and therefore it must be better but no evidence from measuring something on the resulting images.

Will be interesting to see how this all progresses and if images are improved or it just makes people happy because they see a lower calculated RMS and a better looking graph!!

[Skipper Billy]

54 minutes ago, Freddie said:

Thanks, so all your reporting is a reduced RMS when calculated for multi star Vs single, which does no necessarily mean you will see an improvement in the actual image. It may be the case that multi star averages out the seeing and allows for shorter guide exposures and ensures guide commands are only issued when really needed but all I'm seeing being reported is that the RMS improves and therefore it must be better but no evidence from measuring something on the resulting images.

Will be interesting to see how this all progresses and if images are improved or it just makes people happy because they see a lower calculated RMS and a better looking graph!!

Yes that's what I am reporting.

I was just bringing this new facility to peoples attention in case they weren't aware of it and giving some first hand practical feedback as I thought it might be helpful and of interest.

My own outfit tracks at a level where the improvement I saw will make no difference whatsoever to my images. To others it may be the difference between fat bloated stars and nice tight ones.

[Freddie]

Thanks. Yes, let's hope it does actually improve the image for some people rather than just make people feel good about a new RMS number. Will be interesting to see the situation develop over time as more people start to use it and we get some actual image comparisons rather than RMS comparisons.

Would be good if a bit of free software can save people the expense of having to upgrade mounts or replace old worn ones. Time will tell.

[Jonk]

Don't forget, guiding figures of 0.7" RMS or 0.3" RMS won't have much if any of an effect on the image if the image scale is 4" for example (as per David's point above).

However, a zig zaggy guide graph is fine, as long as you understand what's going on. Lower RMS numbers are good, and are more important to look for than the graph.

The conditions play a huge part in guiding and I've also see that a small movement of the mount (i.e. to the next panel of a mosaic) changes the guiding 'result' massively.

The final image is where to look for the result.

[groberts]

Thanks for the update, looks very promising + just what I need.

[stash_old]

when it can see a cloud coming and pause image taking or make the clouds skip around my area of sky - thats when it will be a fantastic piece of software until then its just great free piece of software 🙂

[tooth_dr]

Thanks @Jonk  hadn’t realised this update was available.

I tried it night before and last night and it recorded an RMS about 20% better than my usual. It was sitting at 0.50” total, 0.35” per axis. Normally it’s 0.6”. I never really bother too much because I image at 2.2”/px so anything 1”/px or under  is good for me.  It will however prove useful though for my longer scope which images at 0.95”/px.

👍🏻

[Jonk]

1 hour ago, stash_old said:

when it can see a cloud coming and pause image taking

There is software available to do that but I can’t remember the name at the moment. It was expensive if I remember rightly.

[Jonk]

I’ve just read this elsewhere, and certainly worth mentioning.

In the guiding tab of advanced configuration, check your “Reverse DEC output after meridian flip” setting before and after installing the development version.

Apparently the setting might be changed so it should be checked.

I suppose this advice should be followed for all settings after an upgrade.

[tooth_dr]

3 minutes ago, Jonk said:

I’ve just read this elsewhere, and certainly worth mentioning.

In the guiding tab of advanced configuration, check your “Reverse DEC output after meridian flip” setting before and after installing the development version.

Apparently the setting might be changed so it should be checked.

I suppose this advice should be followed for all settings after an upgrade.

Ive only just got my mesu behaving itself after a MF a few weeks ago, as the dec was going out of control post-flip.  I since have installed this new version, and the mount is still doing MFs properly, so from my perspective, this hasnt changed.   But cheers for the heads-up.

Edited December 11, 2020 by tooth_dr

[Jonk]

Another reason for a non flip pier! 

[blinky]

I’m not doubting that it’s improving things, but has anybody got any images to show? Really interested in somebody like myself, my mount averages around 1” and my imaging cam/scope combo gives about the same, so any improvement should be visible in the images. I’m in Scotland, weather is crap as usual so who knows when I will be able to try it out!

[tooth_dr]

2 minutes ago, blinky said:

I’m not doubting that it’s improving things, but has anybody got any images to show? Really interested in somebody like myself, my mount averages around 1” and my imaging cam/scope combo gives about the same, so any improvement should be visible in the images. I’m in Scotland, weather is crap as usual so who knows when I will be able to try it out!

Sorry I can’t help. My imaging scale is over 2.2”/px so the improvements haven’t been noticeable. 

[Jonk]

 I've been running multi star for about an hour, and it's reporting 0.65" RMS. not sure if this is an improvement, as the sky conditions aren't great and I'm only on a temp tripod setup.

[Jonk]

It dropped to 0.58" RMS for a while, probably conditions, and it has dithered a few times since the screenshot above.

  

[smashing]

Well...I'm running it at the moment and I don't believe the numbers  being shown for my bog standard HEQ5...too good to be true, I must have some settings wrong somewhere...subs look good though

[Jonk]

Maybe do a comparison between a sub without multi star and new sub with (just turn the option on / off in PHD).

I set up my AZ-EQ6 to test something last night with a misty sky and the seeing was incredible, PHD2 reported 0.5" RMS with multi star on.

[tooth_dr]

I have recently been plaqued with glitches from just about every piece of kit I have - cameras not connecting, the mesu going into 'blinky' mode, dome not working - I have ordered a new PC.  Anyway last night midway through last my session I realised that PHD multistar was off, so I flicked it on in the settings, and the guiding settled down almost immediately after a poor beginning to the session.

In the first image I turned it on just to the right of the half way mark.  Image two is from later on in the evening.

 

(Also what it the blue target thing - it just appeared the other day)

 

 

 

Edited January 2, 2021 by tooth_dr