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Old 18-02-2018, 01:10 PM
Startrek (Martin)
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HEQ5 Alignment

Picked up my HEQ5 and Bintel 150mm F6 reflector scope last week and went out last night and this morning for some visual on stars and planets

I have no line of sight to SCP ( my house and large trees obstruct the view) so I carried out a rough polar alignment using the method I described in a previous post ( compass, magnetic declination and digital inclinometer )

Also made up a shadow stick from a 1metre x 10mm dowel set at 90 degrees and used the sun from 11.00am to 1.00pm to find east west then north south at 90degrees.Scribed a line on my pavers to indicate true north south ( did this 3 times to improve the accuracy of true north south )

When I set up the mount, level it and use the compass with magnetic declination, the scribed north south line on the pavers is almost spot on with the compass mag declination line ( use 2 plumb bobs to check )

Installed the mount head

My latitude was set with my digital inclinometer as per my current location

Set the mount up to achieve a home position.( Used myastroscience.com/homeposition and Astronomy shed ) taking into consideration we are in the southern hemisphere with RA and DEC all locked and marked

Installed the Scope and counterweights then carried out balancing as per Astronomy shed ( with all accessories on board )

Aligned the finder scope ( used the antenna of a 2 story house 40m away )

Collimated the scope spot on !

Set up the Syn scan for initialization

Carried out a 2 star alignment using Sirius and Procyon, had to manually centre the stars with the hand controller in the finder scope and then the eye piece ( I can only see about 8 or 9 stars due to being in a metropolitan area with light pollution )

After "Alignment successful" on the Synscan I chose to locate another object, the star Canopus , the mount slewed towards Canopus , looked in the finder scope nothing there , had to manually slew the telescope again quite a bit to centre the star

I thought with my rough polar aligment method I would at least get the chosen star or object in the finder scopes field of view, but obviously I'm a fair bit off.

The same with Jupiter early this morning, I selected Jupiter in the Synscan hand controller and again I was a fair way off in the finder scope

Although the mount did keep the objects in the field of view of the eye piece for some time once I manually centred them ( I'm use to continually nudging my 10" dob down the south coast at my holiday house )

Is my polar alignment that way off ? ( the Syncan did give a read out of the Mel and Maz values. From memory the Mel was pretty close but the Maz was something like 12deg off ?? )

By the way the Bintel 150mm F6 scope is a treat , great little scope !

Any advice or comments greatly appreciated

Martin
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Old 18-02-2018, 02:11 PM
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MattT
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When I owned a synta heq5pro and neq6 I always moved the mount to centre the first star after it slewed to the area, not the hand control buttons.
Second slew I used the hand control buttons to centre the star....always worked for me.
The other thing is getting the exact time to the second helps.
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Old 18-02-2018, 02:30 PM
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doppler (Rick)
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Quote:
Originally Posted by MattT View Post
When I owned a synta heq5pro and neq6 I always moved the mount to centre the first star after it slewed to the area, not the hand control buttons.
Second slew I used the hand control buttons to centre the star....always worked for me.
The other thing is getting the exact time to the second helps.
+1 the first star gives you an idea how far the polar alignment is out. Another tip I found that works is to choose 2 stars not too far apart and still in the same hemisphere (say Canopus and Sirius). 2 star alignment is all I use, 3 star is very finicky.
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Old 18-02-2018, 04:46 PM
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I have had one go at star align but the clouds hit before I could get anywhere but there was something in the questions about polaris..does that mean anything to anyone if so what do I answer?
Alex
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Old 18-02-2018, 05:52 PM
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I opened a thread asking so others who may be in my position can find by a search.
Alex
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Old 19-02-2018, 03:16 PM
breadfan
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Quote:
Originally Posted by doppler View Post
+1 the first star gives you an idea how far the polar alignment is out. Another tip I found that works is to choose 2 stars not too far apart and still in the same hemisphere (say Canopus and Sirius). 2 star alignment is all I use, 3 star is very finicky.
Thank you both for this. I had to do a double take to make sure I wasn't actually OP and hadn't posted this thread while sleepwalking - I had the exact same experience on Saturday night taking my recently purchased HEQ5 out for a first attempt at a properly aligned viewing.

I look forward to getting out tonight and seeing if I can get a better alignment
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Old 19-02-2018, 05:59 PM
astro744
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I did exactly the same stick trick with my son on Saturday. He marked the shadow every 1/2 hour over a few hour span. I double checked with Stellarium when the Sun crossed the meridian and it lined up nicely with the shortest shadow. (Set alt az grid on).

In Sydney the Sun was on the meridian at 13:10 so between 11:00 and 13:00 you hadn't quite got to the shortest shadow. At 13:00 you are 6 deg out. It may make a difference in your alignment.
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Old 19-02-2018, 09:04 PM
Startrek (Martin)
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I did not think of using Stellarium to find out the exact time when the sun traverses the meridian, I just used line of sight over head around midday or so , marked my time points at 11.00am and 1.00pm and ran a line through them for true east / west ( Like you mentioned I could be out by quite a margin )

What 2 time marks did you dissect to achieve your true east / west line and hence your true north / south ?
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Old 20-02-2018, 03:42 AM
astro744
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I figured that the shortest shadow would give me the true north south line. I put a 600mm piece of 16mm dowel into the ground on the north side of a 600mm x 400 mm concrete paver. I made sure the stick was level north south and east west. In the morning as soon as the tip of the stick's shadow hit the paver I marked the spot with an X, (at least my son did this as it was a little science experiment for him). Each 1/2 hour or so ( interval not critical) we marked the tip of the shadow.

I was curious as to when local noon was and since I had my iPad with me I used Stellarium and set up an alt az grid and looked north at the position of the Sun. I dragged the sky until the Sun crossed zero and noted the time. I marked the shadow at this time and also two more times after local noon.

i then drew a line through all the crosses and measured the distance from the stick to each marked cross and any part of the line they were on and the shortest one was indeed when the Sun was on the meridian as found in Stellarium. I felt that using Stellarium was 'cheating' a bit but since it wasn't for school as my son had already done this experiment it didn't matter and it was a good way of checking the result.

I did the shadow trick a long time ago without Stellarium and marked the north south line but it had washed off over time. This time I also placed another stick on the south side of my paver inline with the shortest shadow line and then also placed a tomato stake near the fence a few metres away. Now all I have to do is stand on the north side of my paver looking south toward the stake and the SCP is up above it.
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Old 20-02-2018, 09:29 PM
Startrek (Martin)
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Thanks for your detailed advice / experience

So therefore to achieve a more accurate true south I should do the following -

1/ install my 12mm x 1m timber dowel at exactly 90deg to the level ground both directions ( pavers )

2/ Jump on Stellarium and find out the exact time of the noon meridian ( 1.08pm )
3/ At 1.08pm mark a line ( approx 500mm ) on the paver from the base of the timber dowel in the exact centre of the short shadow line cast by the timber dowel
4/ The direction of this line should be very close to true south

Correct ??
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Old 21-02-2018, 04:42 AM
astro744
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Correct. I added the other stick near the first (south side of line) and stake a few metres away (southside) as you need three points to define a straight line. When I stand on the north side looking south everything lines up. I left everything in place the first time and then placed my tripod and GEM in place and aligned the polar axis with this new line best I could. Make sure your mount is level and the altitude is set correctly. Also make sure any azimuth adjustment is in the middle of its range.

When all this is done you can fine tune with drift adjustment and then once the tripod is aligned you can mark the position of the tripod feet for easier placement next time.
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Old 21-02-2018, 11:11 AM
jimmyh1555 (James)
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After you have done the 2 star alignment, do a polar alignment - as instructed in the Manual. You must tweak the T-bolts and the azimuth knobs as per instructions, in order to physically correct the alignment of your scope. This gets the Mel and Maz down a bit...... Then..... do it all over again (Polar align) until the Mel and Maz have lots of zero's in them!!
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Old 21-02-2018, 01:37 PM
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jenchris (Jennifer)
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I endorse what Mathew said.
Go for a two star alignment and adjust the mount when it goes to the first star - by doing that it resets the physical aspect - when it goes to the second star it should be really close if you set up the tripod level.
I believe a three star alignment gives you a cone error correction but I may have misinterpreted that .
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Old 21-02-2018, 05:37 PM
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IIS member Trevor Hand wrote up a method that I use.

http://www.iceinspace.com.au/63-498-0-0-1-0.html

This gets to within a degree of the pole.

With the HEQ5 and EQ6 mounts I also chose stars in the same hemisphere.
Canopus and Formahault were always good. Moving the mount with the bolts/screws for the first slew is the key. I only ever did a two star alignment.

Often the first slew was in the finder scope, often 3-4 degrees out. The second slew was often within one degree....then use the hand control to centre.

Phone apps are good enough for levelling the mount and getting a good altitude setting.
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Old 21-02-2018, 09:29 PM
Startrek (Martin)
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I have tested my iPhone compass and level readings against my Accumaster digital inclinometer and Silva ranger 3 compass and the IPhone was out by a couple of degrees, so I opted not to use my IPhone for Astro settings

So there is no issue tweeking the Az knobs and Alt T bolts to manually centre the first star of a 2 star alignment ( in lieu of the hand controller directional buttons ) Does this ensure a better second star alignment and therefore a closer polar

All the responses on this post are great, getting to slowly understand the workings of an EQ mount ( absorbing everything ) You have to just get out there and give it a go , fail, read more advice, try again and again until you succeed.Learning is half the fun, the other half is swearing and throwing eye pieces against your neighbours fence
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Old 22-02-2018, 06:09 AM
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You’ve got it. A frustrating procedure but not as hard as it seems.

Try drift aligning for a bit more refinement, for visual you won’t need it.

http://www.astrotarp.com/drift_method-2.html
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Old 22-02-2018, 10:48 AM
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Robert9 (Robert)
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Hi Martin,
Just been reading through all the great advice you've been receiving. Would like to add one more which you might find also helps.
After turning on your mount and adding general info., before you start with any star alignment procedures, use the controller to go to "Utilities" and select "Park Scope" and go to "Home Position". This will ensure that your mount is always in the exact same "zero" position. There is no need to turn off and turn on the mount afterwards, just return to "Setup" and continue to alignment.
Remember too, that after doing a Polar Alignment, because you mechanically shift the mount in this process, you will need to do a further 2 or 3 star alignment.
Robert
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Old 22-02-2018, 01:00 PM
Startrek (Martin)
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Hi Robert

Thanks for the tip however I have already set up my home position and initiated “park scope”each time I have used the scope

Do you recommend a 2 Star or 3 star alignment ? as most replies have been to perform a 2 Star alignment

Appreciate everyone’s advice, just waiting now for some clear nights
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