Not enough stars visible to 3-star align HEQ5

[parallaxerr]

I took my new HEQ5 out tonight for it's first test run. The aim of the session was simply to get used to Synscan after using Nexstar for years and to practice accurate alignment.

I set the mount up and completed a 3 star align choosing stars from the menu that were visible from my location. I have no view of Polaris, or anything from E through N to W for that matter, due to high trees, but 3 of the listed stars were available, just. The last one was just disappearing behind the trees when I completed the alignment.

Next I drift aligned the mount over about an hour and got next to zero drift in Alt and Az so was quite happy and ready to realign. That's where the problem started, now, only one of the listed stars in the 3-star alignment was visible. It seemed the mount was suggesting shed loads of stars to the North and NW, right where I couldn't see them

Is there a solution to this problem? As it stands, I won't be able to reliably align the mount with very short list of alignment stars that Synscan suggested. I remember Nexstar basically aligning off anything bright in the sky!

 

 

[Knighty2112]

Not a hundred percent here, but can’t you add stars into the alignment library of stars to compensate for this? I distinctly remember I could add stars in on my old Synscan atl-az goto mount.

[wookie1965]

I press down to change the star the handset gives me until I find one I can see.(bottom left button)

[parallaxerr]

7 hours ago, Knighty2112 said:

Not a hundred percent here, but can’t you add stars into the alignment library of stars to compensate for this? I distinctly remember I could add stars in on my old Synscan atl-az goto mount.

That would be handy Gus as there were plenty visible to the South. I think with the 3 star alignment, the mount likes to propose stars either side of the Meridian with maximum separation but that's just not possible from my garden, so I'll look in to adding some. I have noticed there's a user object menu, so perhaps if I add them in there, they'll show up under the alignment menu?

6 hours ago, wookie1965 said:

I press down to change the star the handset gives me until I find one I can see.(bottom left button)

Yup, that's what I was doing, but all stars in the list were behind the trees!

[Owmuchonomy]

Reading your post you mention drift alignment so I'm going to assume you are imaging? In that case a 2 star alignment should be used using stars on the same side of the meridian followed by DA or if you are like me use the handset polar alignment routine. The 3 star alignment is really only for removing cone error from the GoTo.

[parallaxerr]

Good point, thanks Chris. I will indeed be imaging with the mount, although last night was a dry run without the camera. I drift aligned with a reticle eyepiece just to get a feel for the new mount. I just read another thread that confirms your point, stating a 2 star alignment on the same side of the meridian as your target is sufficient, which should make life easier.

I realise now I was making another mistake in parking the mount after DA as it was applying the previous PAE to the subsequent alignment and it's "possible" this may have influenced the alignment star list, so I need to make sure I clear the PAE next time.

[parallaxerr]

A bit more research and it looks like there are several alignment star menu options that I need to take a look at:

1. List alignment stars by magnitude or alphabetically....Alphabetically would be easier for me because I have a limited view and I know which stars are visible. This saves scrolling through painfully slow until finding a recognisable star name.

2. Adv. filter....Apparently this option filters the alignment stars to show what the mount considers the best for an accurate alignment. Great if you have a 360° horizon but not so good for a restricted view. Turning it off supposedly allows any named star to be used but relies on the user to choose suitable ones. Too close together and the alignment will be no good, as we know.

[ollypenrice]

If you have good PA a one star alignment should be reasonable. Can't you then go to one part of the sky and re-synch on an object there? After this that whole part of the sky should have acceptable GoTo precision. (I can't remember all the handset menus.)

Since you have limited horizons you can't exploit the full benefit of 3 star aligment, the purpose of which is to give good all-sky pointing accuracy.

Olly

[parallaxerr]

36 minutes ago, ollypenrice said:

If you have good PA a one star alignment should be reasonable. Can't you then go to one part of the sky and re-synch on an object there? After this that whole part of the sky should have acceptable GoTo precision. (I can't remember all the handset menus.)

Since you have limited horizons you can't exploit the full benefit of 3 star aligment, the purpose of which is to give good all-sky pointing accuracy.

Olly

I think that's a reasonable approach Olly although I'm not sure Synscan offers the sync function like Nexstar does? 

My understanding is that instead it uses Pointing Accuracy Enhancement on each alignment star so in theory, a 2-star with PAE on the second star should achieve the same result. If I can open up the alignment star menu to all named stars, I might be on to a winner, it'll just be up to me to select suitable stars.

[spillage]

Will you be using a pc or laptop when you start imaging? 

[parallaxerr]

Just now, spillage said:

Will you be using a pc or laptop when you start imaging? 

Not to start with. I think I know where you're going though - EQMOD allowing for aligning to more stars maybe?

If the handset options aren't available then my hand may be forced, but I do want to try PC free first.

[spillage]

That is fair enough. You can use cdc and choose any stars you want and any number. You slew to the chosen star center it then tell cdc its correctly centered. You are not limited by the number of stars you use.

I used to use this and found useful as you only need to align stars around your target.

[parallaxerr]

That sounds like a good solution spillage, using a pc certainly opens up the options! I have quite a new laptop but it was bought for web surfing only and is painfully slow. I installed a few astro programs too see how it would cope and.....it didn't!

Going to trawl through the handset menus tonight and see if there's any mileage in making the changes listed above, if that works out then I'm going to give a Synguider/Nexguide a bash.

[spillage]

thats odd as I have an old pc running mine and it only has 2gb of ram. If you really want an easy solution using a pc then platesolve is so much easier. It means you can ditch you eyepieces and not have to spend time moving the mount to align stars. What software did you try? it might be worth listing you kit so its easier to help.

spill.

[Starlight 1]

and if you are going to use a computer , you can make a Star map in EQMOD.

[parallaxerr]

I haven't listed my kit because I'm in the process of moving from vis to imaging so everything's chop & change at the mo I will do so once I'm settled though.

It's a very low spec laptop. 2gb RAM & 1.7Ghz dual core IIRC, running Windows 10 (yuk!). Tried PHD2, digicamcontrol and stellarium and got the feeling it would struggle to guide. CPU usage is up at 90+% most of the time with little memory overhead. I'm pretty savvy with computers so have killed all processes that aren't required etc, but it's still pants. I didn't want to find out the hard way by purchasing a ccd guide cam only for it not to cope.

 

[Starlight 1]

MYcomputer is a lot less then the one you have. and I can run every thing for imaging all at the same time with 2 x5musb leads. but I use the same eqmod in evey progam that open.

[spillage]

That should be fine to run phd2. Its similar to my pc but running windows 7. I run phd2 cdc and apt with no issues as imaging uses very few resources. Its when you get to processing the images that a good rig comes in handy. Although I still use my imaging pc to run DSS during the day.

I would suggest that you give phd2 cdc and apt a go on your laptop and set it up to use the simulation guide cam and mount. This will show you that it works (may be slow to start) whilst giving you the chance to use it a bit more indepth before buying more kit.

[parallaxerr]

15 minutes ago, Starlight 1 said:

MYcomputer is a lot less then the one you have. and I can every thing for imaging all at the same with 2 x5musb leads. but I use the same eqmod in evey progam that open.

 

14 minutes ago, spillage said:

That should be fine to run phd2. Its similar to my pc but running windows 7. I run phd2 cdc and apt with no issues as imaging uses very few resources. Its when you get to processing the images that a good rig comes in handy. Although I still use my imaging pc to run DSS during the day.

I would suggest that you give phd2 cdc and apt a go on your laptop and set it up to use the simulation guide cam and mount. This will show you that it works (may be slow to start) whilst giving you the chance to use it a bit more indepth before buying more kit.

Hmm, well it sounds like I was being a bit harsh on the little lappy then. I was dissapointed as it's a fanless, ultra slim design with SSD and the battery life is excellent, I don't charge it for days on end.

I'd like to run the digicamcontrol software for Nikon DSLR too as it dumps the image files straight to an externall HDD via USB, saves messing about with SD cards. I've got a high end, water cooled, overclocked desktop in the house for processing so just moving the external HDD across would be easy. Aslo, I could run everything remotely from indoors

The nail in the coffin with the laptop though was that, at first, digicamcontrol worked fine, but, the next day after installing it went pear shaped. The splash screen showed up and the program could be seen running in the processes tab, but the program was not visible on screen. I read that sometimes programs can run off screen, I tried everything to get it visible, to no avail. Even re-installed but no joy. If I could fix that issue, it may be game on again.

[spillage]

Just seen that apt 3.37 beta has nikon support!!!! That might be a real problem solver for you.

[parallaxerr]

5 minutes ago, spillage said:

Just seen that apt 3.37 beta has nikon support!!!! That might be a real problem solver for you.

Sadly my D3200 Nikon is not supported. Nikon never released a SDK for the D3xxx series so it's always in the unsupported list

So long as I have this camera, I'll have to resort to doing many things manually which is kind of another reason I wanted to go PC free, it'll all end up a bit of a hybrid affair. Nonetheless, PHD is surely a better option than a stand alone guider and if I can get digicamcontrol sorted I can at least use it for previewing, focusing and transferring images.

[parallaxerr]

UPDATE:

I have turned off the Adv. Filter option on the handset and set alignment stars to list alphabetically. I set the time/date to the same time as last nights session and sure enough, there are more alignment stars available in the list. Not a whole lot more mind, but I'd say about 50% more and plenty more recognizable names, so it's a good start.

I have revisited the laptop too and made some progress. It seems I had a version of digicamcontrol installed that I couldn't really identify. The version number seemed to suggest it was newer than even the current beta release, very odd. Anyway I re-installed the latest stable version and it's working OK. I also installed the latest version of PHD2 and Stellarium, leaving not much room left on the small system SSD, but performance seems much better than previously noted. I now have it running via Teamviewer to see how it copes remotely and it looks good, although I'll need a wifi booster for it to work from the garden.

Definitely opens up the option of a proper CCD for guiding as opposed to a standalone.

 

[spillage]

Sounds like your making good progress. For me it seems to be one of those hobbies that you want things to be made easier (piers, computers, goto, platesolve) but not having so much tech that is all get out of hand and and evenings imaging is more like launching space x after its been put together by bmc in the 70s.

[Geoff Lister]

Jon,

I too had problems when the selected star had the 'scope pointing towards the side of my house or garden fence. I tend to use the "Brightest Star" alignment method, rather than stepping through the whole list.

This is what I have done for my Alt-Az mounts:-

I used "Stellarium" on my PC, and by incrementing the time and date for dusk, in the middle of each month, I produced a table of 26 bright stars, selecting, 3, 4, or 5, for each month, giving a 20 to 40 degree altitude and 60 to 120 degree azimuth spread, and listing them with a general direction (N, NW etc.), in which to find them. As dusk advances, the Stellarium display starts to add the names of the brightest stars, just as you would see them appear as it gets dark. These are the easiest ones to go for, and a single set for the middle of each month gives me adequate information for the whole month. As you know your blind arcs, it should be possible to produce a table compatible with an EQ mount.

You mention that you cannot see Polaris. From my understanding, using Polaris, on a polar-aligned EQ mount, provides little useful information to the Synscan alignment software.

Geoff

 

 

 

[parallaxerr]

On 22/09/2017 at 20:53, spillage said:

Sounds like your making good progress. For me it seems to be one of those hobbies that you want things to be made easier (piers, computers, goto, platesolve) but not having so much tech that is all get out of hand and and evenings imaging is more like launching space x after its been put together by bmc in the 70s.

Haha a BMC rocket, wouldn't that be something! I'm leaning more towards a guidecam and pc setup now the laptop is behaving, what software would I need to align from any star? You mention cdc, does that require ASCOM/EQMOD?

 

21 minutes ago, Geoff Lister said:

Jon,

I too had problems when the selected star had the 'scope pointing towards the side of my house or garden fence. I tend to use the "Brightest Star" alignment method, rather than stepping through the whole list.

This is what I have done for my Alt-Az mounts:-

I used "Stellarium" on my PC, and by incrementing the time and date for dusk, in the middle of each month, I produced a table of 26 bright stars, selecting, 3, 4, or 5, for each month, giving a 20 to 40 degree altitude and 60 to 120 degree azimuth spread, and listing them with a general direction (N, NW etc.), in which to find them. As dusk advances, the Stellarium display starts to add the names of the brightest stars, just as you would see them appear as it gets dark. These are the easiest ones to go for, and a single set for the middle of each month gives me adequate information for the whole month. As you know your blind arcs, it should be possible to produce a table compatible with an EQ mount.

You mention that you cannot see Polaris. From my understanding, using Polaris, on a polar-aligned EQ mount, provides little useful information to the Synscan alignment software.

Geoff

Hi Geoff,

I use Stellarium in a similar way but the problem I have is that, regardless of how many bright stars suitable for alignment there are in my visible field of view, very few of them are listed in the SynScan alignment menu. I did manage to open a few more options up as I mentioned above, but haven't had a clear night since to test.