Playing with the Jewel Box - Drift Alignment problems

[Andy01]

Hi All,

Had another go last night with the Drift alignment. It's still not quite right, so any and all advice is welcome.

I'm trying to use the technique from Pete's Astrography http://petesastrophotography.com/ind...alignment.html (http://petesastrophotography.com/index.html?mainframe=http://petesastrophotography.com/polaralignment.html)

I'm using a Saxon ED 120 on a go to EQ5 - I purchased a 20mm illuminated recticle eyepiece to try getting more accurate alignment - it's an improvement, but I still struggle with this..Tips?

All the long exposures showed too much movement, so I have here a sharpish frame of the Jewel Box. 3 secs @ 1600iso.

Not perfect so I played with it photoshop (a lot) and so it's more of an Artist's impression than reality, but it looks ok.

Thanks for looking : )

Andy

[DarthWombat]

Very nice!

I have an identical telescope and I'd certainly be happy with that shot.

Did you use prime focus to get that? I am still trying to get to grips with my gear so I'd be interested in swapping notes.

Hooroo,

Alex

[Poita]

What is the camera? You may need to unbalance the scope slightly, but if using a DSLR the movement could be vibration from firing the shutter.

Post a 30 second exposure and we can see far more clearly where the issues lie.
Using a camera is a far better way to do drift aligning, or a 12mm or smaller eyepiece, 20mm is a bit too inaccurate I find.
Even a webcam can do wonders.

[Nico13]

Yes a web cam is a very quick way to drift align using PHD even if you don't actually use it for guiding you can use it to do your initial setup and drift checks.
Once you're happy with your alignment take the web cam off and away you go.

To use that to drift align in PHD turn guiding off and forced calibration off then in PHD tools select the graph it will show your drift then pick a star in the PHD window and hit guide.

The graph will draw two lines RA and DEC they should track along close to center if polar alignment is close, as long as you have your latitude/DEC angle set pretty close it will mainly be the RA line that will wander off up or down.

All you need to do is adjust the mount on its base left or right to stop the drift and it happens quite quickly so it's easy to see it happening and make adjustments. If you adjust it one way and it gets worse then you've gone the wrong way so just go back the other way an equal amount by x 2 and you can fine tune it in a matter off minutes. The same can be done with the DEC axis adjustment.

For RA pick a star around the ecliptic and for DEC one more South, I usually cheat and just pick one in the south east and do both there for a quicky and that works pretty good if you,re guiding.

Hope this helps if decide to try it.:)

[Andy01]

Hi Nico & Poita,

Thanks for the tips :)

Sorry but I'm very used to photography after a lifetime of working in it but I'm an absolute newbie at astrophotography. What's PHD?

I'm using a Fuji S5 Pro Dslr, manually focused by eye. I'm using a remote release, mirror lockup and a 10 sec delay between locking up the mirror and firing the shutter.

I do have a mac laptop so maybe I can have a go at connecting the little celestron webcam that came with the 'scope 2nd hand if I can find a mac compatable driver for it. Not sure if one exists - unfortunately it looks like most of the astro software is written for PC's and Canon cameras! But I'm determined to succeed, the universe is just so cool!

On the other hand, I've only been doing this for a few weeks, so maybe I'm just impatient!

Thanks for your input, it really helps!

Cheers
Andy

[Nico13]

Here you go Andy
Have a look at this site, a lot of people use it and it works well.

PHD (Push Here Dummy) They said that not me :P

http://www.stark-labs.com/phdguiding.html

This will tell you all about it and it runs on MAC so if you can get a driver for the webcam you're set.

Oh and don't worry about your FUJI I use a Pentax and do exactly what your doing. :thumbsup:

[Andy01]

Hey thanks Nico!

I had avoided Stark/Nebulosity as it wasn't Nikon (I also have a D700) or Fuji compatible, but will research the webcam idea, that's cool.

I was sort of hoping that I wouldn't need to use the laptop or a guidescope yet, but it seems an inevitable next step to get the results you guys are showing on this site, oh well- another negotiation coming up with the finance minister methinks!

All good for one's Neuroplasticity eh?

Cheers
Andy

[The_bluester]

Hey AC. If you can come out to Kilmore we can try the webcam using my (PC) laptop so you can see if that helps you before worrying about trying to find ways to do it with a Mac or buying a PC based one.

Also, if your 20mm reticle is 1.25" (Assuming it is) we could use my barlowe to up it to 10mm equivalent so any movement in the alignment is more pronounced.

[Andy01]

Hey Bluester, that's a tempting offer! (Yes the 20mm is a 1.25" eyepiece).

I'll do a bit of research on PHD today, thanks Nico.

Darth Wombat, I'm happy to compare notes. I have a FB page with some diary notes & images from my Astrophotography adventures with the Saxon to date.

https://www.facebook.com/AndysAstropix

[Andy01]

Hey Poita,

Here is a 20 sec exposure from the same session FYI.
What do you think?

Cheers
Andy

[Poita]

I can loan you a 12.5mm illuminated eyepiece if you email me your address I'll post it on up. (click on my name and choose send email)

I can help you get your mac involved as well, drop me a line.

[Poita]

BTW, do you have the synscan controller? What version firmware is it running?

[Poita]

I'm guessing that your initial alignment is way off before you start drift alignment. It may be worth getting the physical alignment a little closer before starting the drift alignment.

How are you determining that your mount is pointing south (compass? Solar Noon method?) and do you have access to an inclinometer or a protractor and plumb-bob? The markings on the mount are often out by a number of degrees, so that is worth checking too.

[Andy01]

Hi again,
Synscan V 3.27
I'm using the compass in the iPhone.
Only problem is its a bit hard to really tell If the tripod "South" leg is actually pointing due south.
Maybe I need to knock up a makeshift alignment Gadget?
Seems a bit manual, but I'd like to find a more consistent method.
Cheers
Andy

[scagman]

Hi Andy,

When setting up your mount, are you pointing to true south. You need to point your tripod 11deg east of south. I may have my terms mixed up a bit but you point your tripod to true south and not magnetic south.

Cheers

[pixelsaurus]

Apparently this should also be called digital south.

[tlgerdes]

Have to say Andrew, your thread title is a little............. open minded;) :P

[silv]

Trevor :lol:

Andy, if you look closely at the star trails: are they even lines or do they show bumps? Maybe take a 30 secs exposure to see it better.
I'm asking because the EQ5 is listed with 9kg max load and the tube alone weighs 5.13kg - not including rings, finder, camera, dove tail bar etc.
The mount might be "aching" while tracking the load and that also adds to the trails.

Just saying... good to keep that in mind and not to expect too much :)

Your first image looks really pretty. Impressive what can be done with 3 secs exposures!

[Poita]

To get lined up, one of the easiest ways is to use the Solar Noon method.

For Melbourne from today through to Sunday 19th Solar Noon is at 12:24 (i.e. 24 minutes after midday).

If you have a plumb-bob you can hang it up where you want your mount to go, and at 12:24 the shadow the string casts on the ground will be perfectly north-south.

Or use a tomato stake or similar if you drive it in and check that it is perfectly vertical/level and it will cast a North-South shadow at 12:24.

If you stand up straight, your own shadow will do the same :)

This will let you check your alignment in a quick and fool-proof way.

(If in Sydney Solar noon will be at 11:59)

If you mark the line on the ground, you will always have a reference point. I hammered two long roofing screws into the ground so just their heads are visible, marking the north-south line on my lawn.

If you then use an inclinometer to set the mount as well, you will be pretty close before you begin drift alignment.

[Andy01]

Great suggestions everyone, the astronomy community is amazing!

Here's my drift alignment fix action plan -

- check the 'scope balance
- mark Due South on the Lawn
- upgrade the Synscan firmware to v3.28
- try PHD & the webcam (assuming I can get the Mac book to talk to it.)

Hopefully that should solve the problems so I can get on with taking some decent pictures!

Many thanks for all of your valuable input & tips! I'll keep you updated.
Now if only these clouds will go away....

Andy

[Poita]

Only thing to remember is that it is easier if you lay down some paper or white fabric to see the Sun's shadow more clearly on the ground.

Also, make sure your adjustment bolts are set back to the 'middle' so that the mount is actually pointing evenly along its axis.

I know some people use a line-laser attached to the mount to shine a line onto the ground to make it easier to align.

[Nico13]

Yep, highly recommend using the solar noon method, works a treat. :thumbsup:

[loki78]

With a few recommendations to the solar noon method, the question has to be asked, how do you determine it for any given time of the year and any location?

[silv]

you can look it up here for your location and date. :)

http://www.esrl.noaa.gov/gmd/grad/solcalc/

[Andy01]

Progress report...

1- rebalanced scope - tube was slightly out of balance
2- successfully upgraded Synscan firmware to v3.28 b21
(that was hard work, had to borrow an IT savvy mate and his PC and find a ton of drivers on the net but job done now!)
3- installed macam and PHD to the Mac laptop
(Celestron neximage talks to macam, looks like that will work, but it won't talk to PHD or the mount, any ideas?)

Anyway, if the Melbourne clouds ever lift, I'll get on with some imaging!
It's not an easy road to travel, but if was, everyone would do it!

Thanks again for the suggestion everyone!

Best regards
Andy

[Nico13]

Hi Andy,
It won't have to talk to the mount to do the drift alignment checks.
Does PHD connect to the camera ok?

[Andy01]

Hi Nico,

No unfortunately PHD isn't seeing the camera or the mount, they're not appearing on the drop down list.

Any suggestions? The macam seems to be working with the camera ok.

Cheers
Andy

[Nico13]

Sorry mate, not a Mac user, closest I go is an iPhone and a iPad :D

[silv]

PHD on OS X needs a kind of translating software to be able to see the mount and guide it.
Look at the Feature list on the PHD website: http://www.stark-labs.com/phdguiding.html
It lists 3 or 4 different options for OS X.

That page also lists the cameras supported in PHD on OS X.


I have not done this, yet, and can't give any more info. :)

Do a search here on the forum for PHD and mac.

[silv]

alternatively, you could run Windows on your Mac and use PHD on that platform - which is a far more common setup and help is easier to get.
If you're not particularly computer savvy the initial setup would be worth it so that more people here can help you along once that is configured.

Virtual Box (https://www.virtualbox.org/)is free. It lets you run a virtual Windows environment "in a box" on your Mac.
You'd need a CD with a true licence of WinXP or higher - an OEM version which came with a PC would not work.

:)

If your camera is supported by PHD on OSX then I'd stay on OSX. But if you find that your camera is not supported then Windows in Virtual Box would be the way to go.

Hope you friend is still your friend! :thumbsup:

[Poita]

For solar noon I like this site, as it lets you print out a year calendar worth.

http://www.solar-noon.com/

[Andy01]

Still too cloudy in Melbourne to get the scope out : (

Meanwhile, I tried hooking up PHD to the Mac, downloaded & installed the Keyspann serial port driver to connect the EQ5 mount via the USB adapter- but I'm stuffed if I can configure it! It keeps looking for a modem, what the? Wierd.
Also downloaded & installed Equinox Pro which talks to the mount ok through the serial port adapter. Supposedly it works with PHD but they're not talking to each other!

I don't get it, 95% of the worldwide professional photography community including my own studio use macs, but most astrophotography software is written for the PC! D'oh! Guess its just different.
It's doing my head in but I'm going to persevere : )

There are some incredibly talented people on this site, taking some beautiful and inspiring images, and I'm very keen to learn!

But if it was easy, everyone would do it eh?

Rant over, hope the clouds clear again soon!

Warmly
Andy

[cjamo9]

hi, your gear is much better than mine i dont understand how come you cant get longer exposures, do you do a 3 star alighnment with the goto. is your scope faceing true south not magnetic south, properly leveled and at the right angle. id be thinking about the coordinates for your global position etc being put into your mount. only other thing would be balance unless some problem with the software. go figure you really should be able to get a lot longer than several seconds out of that gear even without guiding. a longer exposure would be good to see the movement. is the movement always the same.

[cjamo9]

your iphone compase is badly affected by any metal but not alloy. get a 1 meter lenght of aluminium angle and put your phone on that and hold it against a flat part of your mount at the other end of the angle. make sure you callibrate your phone as well by doing figure eights away from the mount.

[cjamo9]

keep your phone away from say a digital wrist watch and if its in a flip case get it away from the magnetic latch.

[Andy01]

Hi Clinton,

Thanks for your input :)

- Yes, can do 3 star alignment with goto no problem
- yes, believe I'm facing true south, not magnetic - but can't confirm by polar noon method as it's been too cloudy in Melbourne lately.
- yes, tripod is level.
- interesting about the iphone compass, will rectify soon as the sun is out!
- hoping for better results now that Synscan firmware v3.28b21 is installed
as it has a polar alignment function.

Come on Melbourne, give us a couple of clear nights please!

Andy

[Poita]

Hopefully the sun will come out and you can do a solar noon check, you might be surprised how far off your mount is pointing. Make sure the adjustments on the mount bolts are 'zerod' i.e. that they are equal so the mount is centred.

[bazaud]

Thanks for the solar noon method.... my back deck now has dots and lines all over it. :thanx: :D

Barry

[Andy01]

10 cloudy nights in a row in Melbourne : ( D'oh!

[Rex]

Hi Andrew,
If you need some help with drift alignment there is a great simulator at the link below that I found really helped me. You can set it to simulate the type of scope you have, ie. reflector or refractor as the directions of drift and directions of corrections will be different depending on your scope type. Anyway you may find this helps, I did.

http://www.petesastrophotography.com/index.html

[Andy01]

Thanks Rex - already been practising that one! I'm probably just impatient.
Hoping the Synscan firmware upgrade will help with the new polar alignment function on board.

Biggest problem is Melbournes weather right now, cloudy nights 13 days in a row, even getting up @ 4am to check so no chance to practise : (

Probably nice in Townsville though I'm betting!

[Nikolas]

So sick of Melbourne's weather currently