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Foxinsox
29-05-2017, 09:21 PM
Can anyone share please with me their experiences and tips to drift align their equatorial mount . I have an EQ6 mount.

kens
29-05-2017, 10:47 PM
For visual, a drift aligmnent should not really be necessary. Do a 3-star alignment with the handset and check the polar alignment error. If its a long way out, follow the instructions and adjust alt/az bolts then redo the 3-star alignment.
For astrophotography, use the PHD2 drift alignment tool.
With the EQ6, take care with the altitude bolts. Carefully take up the weight of the counterweight bar before adjusting those bolts.

glend
30-05-2017, 12:40 AM
Or just use Sharpcap 2.9s polar alignment tool. Much quicker than drift alignment, takes just a few minutes, and its free.

astro744
30-05-2017, 01:28 AM
See https://www.assa.org.au/resources/equipment-reviews/polar-alignment/

http://www.minorplanet.info/ObsGuides/Misc/DriftPolarAlignment.htm

(Follow rules for Southern Hemisphere #1 & #2)

Ensure that the base of your EQ head is level. Note the azimuth of the base should be geographic N-S not magnetic so if using a compass allow for the magnetic deviation. The altitude should be set to your latitude with the polar axis pointing to the SCP.

No 'electronics' needed just RA motor engaged at sidereal rate and and illuminated crosshair eyepiece. Align crosshairs so they point N-S/E-W. Easily done by switching off motor drive briefly. If double crosshair centre star in box, if single crosshair defocus star and centre crosshair on it. May need slightly brighter star if using defocused image.

Once you have aligned mark the position of the tripod feet on the ground so that next time it is quicker to do and don't adjust any altitude and azimuth knobs in the meantime as they will be set for your location with only the slightest tweak if needed.

MattT
30-05-2017, 07:58 AM
One more...http://www.astrotarp.com/drift_method-2.html

I find this one easy to understand and use...trees block the SCP for me.

croweater
30-05-2017, 02:05 PM
Hi , I use this old tip from "Southern Astronomy" to work out adjustment directions for polar alighnment. Makes it a lot easier to avoid confusion.I had to take photo as my scanner is kaput. Apologies a bit blurry. Cheers Richard.

SA_Dolphin_22
11-06-2017, 10:21 PM
If you are able to attach a DSLR to the scope then this will work.
It is quick and really easy to complete and the added bonus is accurate as well. :thumbsup:
Use a red dot finder to determine the direction of nth and east and the others are straight forward.

As has been previously stated your mount must be level, and pointed in the correct direction to start with. Mag variation will come into account but using the D.A.R.V method will also incorporate this (will mean a lot of azimuth movement to start with). I use a length of wood with a 90 degree line marked and then an 8 degree to the right of this to allow for the Mag Var. I do this when first setting up and it means only a small movement is required most of the time. for level I use the mobile phone with a level app which is easy then to set to your current latitude. All in all as the good Alexander the meerkat states, 'Simples'. :lol: ;).

On the preview I am not seeing my attachment so if it did not appear then use google and look up D.A.R.V, Drift Alignment by Robert Vice.

Retrograde
12-06-2017, 07:50 AM
There is a pretty decent summary of drift alignment here on the Ice in Space forum: http://www.iceinspace.com.au/63-405-0-0-1-0.html

I'm rather old-school and use an illuminated cross-hair eyepiece to do my drift alignment. I find it takes roughly 30 minutes to get an alignment good enough for long-exposure photography. As can be seen from the above posts there are many ways to achieve a good polar alignment so find one that works for you :thumbsup:

rrussell1962
12-06-2017, 11:41 AM
I found this one useful. If you look at what the author refers to as the Collins method you can mess around with the formulae, make some approximations and get an idea as to how much you need to adjust relative to the observed drift. Also has nice representations of which way you adjust relative to the drift for different types of telescopes with and without diagonals.

http://shadycrypt.com/pages/Polar/Polar.htm

SuperG
15-06-2017, 10:30 PM
I image from cricket pitches in darker areas. This lend itself to a normally horizontal surface. Sorry writing this on my phone.
1. You tripod probably has an N on one if the legs; point this to the south (use your smart phone or compass.
2. Turn you scope so it points directly north and focus your dslr on a star near the horizon.
3. You have a newt. Using an external/ cable cam trigger and also bulb mode press and hold to open the shutter for 10 seconds. This will serve as a start marker. .
4. Move the star in a vertical direction at a slew speed of 2 for 30 seconds. Then immediately reverse the direction for the same amount of time. I count in my head.
5. Release the cam shutter and view the image. It will probably look like a V shape or upside down v.
6. Lift the mount gently and turn a few degrees to the east or west and repeat steps 2-6 till the v shape turns to a single line.
7. The the scope to the east and focus on a star near the horizon. You will need to respeat the process above but the star needs to be moved left or right rather than up or down. For this step adjust the mount latitude angle up or down till the v line becomes a single line.