Basic alignment

[Uriabraham (Uri)]

Hi everyone,
I started making my first steps into this hobby...
I am still struggling with the initial alignment and have problems with the Goto mount not positioning correctly to the selected object and I need to slew manually to it + the mount tracking is drifting. I have a few questions

1. The mount latitude scale: Melbourne is about -38 degrees so the mount latitude scale needs to be adjusted to 38. I am not sure about my mount accuracy so I prefer using iPhone Inclinometer. I do this by measuring the slope of the OTA or the dovetail and adjust the mount screws to get 38 degrees displayed on the inclinometer, I assume this should be correct, am I right here ?

2. I am using a compass which I believe is accurate enough to setup the tripod towards the south pole (12 degrees east), how important is this direction when it comes to the initial alignment of my Goto mount ?

System: Saxon ED120 OTA, Celestron CG5 Goto mount

any help appreciated
Uri

[mplanet62 (Michael)]

Hi Uri,
Welcome to the Forum!
First - phone inclinometer is not precise, especially near some mass of metal (which the scope is). Does your EQ (I assume) mount have a latitude scale? If not, buy a simple mechanical inclinometer off e-bay (10-15$). It's not hard to make the simplest one from a protractor.
The same goes for a compass. Don't put it on the tube. Magnetic declination figure for Melbourne is generally correct. Mind it, magnetic alignment is pretty rough - so you will need to adjust the view occasionally - depending on magnification.
Cheers,

[Uriabraham (Uri)]

Thanks Michael,

I believe the iPhone Inclinometer uses a gyroscope and unlike a compass is not affected by metal. I get getting same reading regardless of position on the scope
My mount does have latitude scale but I am not certain how accurate it is so that’s why I thought using the Inclinometer instead
I put the compass on a piece of timber attached to the tripod about 1m far so this should be ok ?

The problem I am having is the scope not slewing close enough to the selected object and drift in tracking, could bad alignment be the cause ?
cheers, Uri

[MattT]

Hi Uri,
In at the deep end... a bit. It took me a year to work out my HEQ5pro so here goes.
1. Look up IIS member Brendan Mitchell's web page. His set up of synta mounts is easy to read and understand.You can find him just about everywhere on the forum
2. Is the mount level before you use the inclinometer? It needs to be.I use that app too and it works .
3.11-12 degrees east is correct.
4. I always find that I have to move the mount physically with the alt and atz controls to get the first star centred in the alignment procedure, no matter how accurate I think I have done the set up.
5. The synta manual is next to useless, a lot of trial and error and asking questions is the way to do it.
So after all that last night( first for a while) I set up and got Acrux as my first star...so far so good, 2nd star I chose Sirius only to have the thing go way out Acrux turned out to be Gacurx, I also need brain power which some days is sadly lacking.
Cheers Matt

[Uriabraham (Uri)]

Thank you Matt,

The mount is levelled (based on my iPhone Inclinometer which is think is more precise than the bubble on the mount)

In my areas these days Sirius and canopus are suggested by the Goto mount and I am pretty certain I aim to these stars. I tried also with star calibration to see if I get better results but no luck either, after alignment the mount slews close to the object (e.g Saturn) but not close enough,
Yes, perhaps learning the hard way by trial and error is the way

Cheers, Uri

[mplanet62 (Michael)]

Google for meridian flip to resolve slewing issue. I'd rather trust latitude scale over mobile phone level - but that's just my opinion.
Good luck!

[Uriabraham (Uri)]

Thanks Michael, I will do some more reading re meridian flip, however i am expecting the Goto mount to be smart enough to only suggest relevant stars for alignement. Uri

[mplanet62 (Michael)]

Now I see - It's actually a GOTO problem. It might have nothing to do with magnetic alignment, but with South/North hemisphere switch and time settings. Cannot give any advice on that - have no practical experience. Hopefully, someone will follow.

[bmitchell82 (Brendan)]

Your issues are more to do with polar alignment than anything else! So learn how to polar align and your life will be alot better...

If you go to my website I go though how to set up a eq6, but this is easily transfered to other types of mounts!

www.brendanmitchell.net

Navigate your way to resources and look for the EQ6 setup

[mikerr (Michael)]

Uri, I think you sould be setting the lattitude to 52 Degrees when resting your inclinometer on the tube or dove tail. This is the Co-Latitude for your location. 90 minus 38 = 52 degrees.

Can someone else chime in if I have got this wrong!!!

Michael.

[Uriabraham (Uri)]

Hmmm, I don't think you are right here. The angle showing on the mount scale is very close to 38*. However , 90-38=52*would be the angle of the weights axle, makes sense ?
Thanks Mike

[Uriabraham (Uri)]

Thanks Brendan, I have looked at your polar alignment guide, however my understanding is that if you setup the tripod to point to the true south 12* east to the magnetic south then no need to do polar alignment , cheers , Uri

[seeker372011 (Narayan)]

With the CG5 and for visual you need only rough polar alignment

What you must do is add at least one calibration star
Two is better

Once you have star aligned you can if you wish improve your polar alignment bu using the CG 5 all star polar alignment feature

But you shouldn't have to do it for visual

Have you checked to see that the mount is set for sidereal tracking and that hasnt inadvertently been turned off?

[Uriabraham (Uri)]

Thanks Narayn, I will check to see the tracking mode is set to sidereal
If I position the tripod 12* east from magnetic pole and do 2 star alignment and add one calibration star , would that be all I need to do for the goto to be precise and slew right to the selected object ?
Cheers and thanks, Uri

[seeker372011 (Narayan)]

With the CG5 and for visual you need only rough polar alignment

What you must do is add at least one calibration star
Two is better

Once you have star aligned you can if you wish improve your polar alignment bu using the CG 5 all star polar alignment feature

But you shouldn't have to do it for visual

Have you checked to see that the mount is set for sidereal tracking and that hasnt inadvertently been turned off?

[bmitchell82 (Brendan)]

...

Just use your phones inclometer to get you in the ball park
Use a compass (not your phone one they are not reliable) to get your basic south bearing. if you have a kick ass magnetic offset just remember it for your location. Perth has 1.2 deg or so, I don't bother with it because its too small.

If you are just doing visual, slew to a star near the SCP, physically move the mount to where the mount points the scope. aka Slew to Acrux, put the hand controller down. loosen the Azimith (two knobs at the front of the mount) grab the mount and twist. loosen the front altitude adjustment off completely then use the back one to adjust the mount up or down. Using a combination of both align the star in say a 10 or 12mm eye piece. You will be close enough to the SCP then to do visual with reasonable accuracy.

If you are learning to do photography use either the latest update for the synscan hand controller or alignmaster to get your polar alignment. You can use drift alignment but it takes a lot longer to get it right. Within 10-15 minutes I have good enough Polar alignment land every target on within 10 arc min on a small sensor. Generally drift alignment you have to wait 10 minutes each adjustment. Dont get me wrong if you are in a perm setup then drift aligning is good unless you have a PME type of mount with Tpoint or Maxpoint where it actually models your mount and a whole heap of other things. once again not needed in a set up and shoot every time system

I wouldn't fart around with getting protractors and the like as your time would be spent better haivng a cold beer! I don't have protractors and other fancy gizmos with plum bobs and what not because you don't need them with the technology thats about today!

BM

PS. you should be around the 35-40 deg in altitude just go off the side disk...
Just read your response. unless you have utter faith in your compass (I don't) use the method i state above or it will do you over 9 times out of 10...

[seeker372011 (Narayan)]

Sorry for the double post I am trying to do this on a Vodafail phone and it's is shocking

Yes you should have no problem landing objects in a 20 mm eyepiece

I have an EQ6 as well as a CG5 and my experience has been with sufficient calibration stars the CG5 was more accurate in landing stuff in the eyepiece
Especially deep space. Slightly less reliable for planets but not terrible by a long chalk

[Uriabraham (Uri)]

The tracking settings are: mode=eq-south
Rate=sidereal
Is this right ?
Thanks heaps

[mikerr (Michael)]

Uri, this might make how the Latitude setting relates, a bit clearer...

http://www.iceinspace.com.au/forum/s...ad.php?t=73387

Michael.

[seeker372011 (Narayan)]

Originally Posted by Uriabraham

The tracking settings are: mode=eq-south
Rate=sidereal
Is this right ?
Thanks heaps

Yep