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HEQ5 Pro star trailing issues

Gohan75

By Gohan75
in Getting Started With Imaging

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Gohan75

Gohan75

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Hi all, recently took the plunge on a second hand HEQ5 Pro, i am happy with it but having a few issues with regards to tracking.

1. Polar alignment : I use the polar scope to get Polaris in the centre of the circle, however if i go back to check it later Polaris has moved out out the circle?? Am i doing something wrong? I had assumed the circle would move as time input into handset progressed?

2. - When doing 3 star alignment i find that often i am limited to stars that i can choose from. Last night when doing 2nd star alignment i found that all the choices were in one section of the sky, a part completely out of view from my location, is there anyway around this?

3. Having done a 2 star alignment and polar alignment (i think correctly) i could only get about 30 seconds before star trails emerged which was frustrating! Any reasons for this? Am i doing somehting Wrong?

Thanks.

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Matt Scunthorpe

Matt Scunthorpe

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1. How are you doing the polar alignment, also do you level the tripod. People say it doesnt matter so much, but to me personally, i find it does make a difference.

You need to turn the RA around, so that the circle that polaris sits into is at the bottom as you look through the scope. Then using your dials, set the time that the handset tells you (HA 1620 for example), using the BOTTOM set of numbers. This will turn the circle to its correct position, then you can put polaris into the circle. The circle will move as you move the RA, so it will move out of the circle as you slew around.

There is a video guide to this on astronomyshed, that i will try to find if you dont do it this way and dont understand my ramblings (which is very likely).

There also may be other ways to do the alignment correctly, but this is the way i use.

2. If you look on the setup options, there is one called alignment stars, you can choose for it to automatic, or choose it list all stars by magnitude or alphabetically. I have the same problem in that when i set up in the garden, i dont have many stars to choose from. A star map is handy here, so you can choose stars you know you can see.

3. This can only be your tracking, which is back in part 1.

I will search for the video now, but im at work so probs wont be able to get to it.

Hope that helps.

Matt.

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Gohan75

Gohan75

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Thanks Matt, it seems that maybe i have not been Polar aligning properly, i just get Polaris in the circle n assume that its done. I have not been using the RA circles or anything like that. Perhaps this is the reason for bad tracking then? 

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Matt Scunthorpe

Matt Scunthorpe

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I think its worth remembering that Polaris isnt the north pole, its just close to it, polaris orbits around the pole as all the other stars do, its just not obvious because its such a small orbit. So, its not always going to be in a set position in that circle.

Let us know how you get on after youve read it, and hopefully will get a clear sky to test it. I still struggle sometimes, but i can get about 1min to 1min and a half without trails, but i am using the 200p on the heq5, which like i said in a post yesterday is pushing it, and kinda acts like a kite when theres a breeze!

Matt.

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lensman57

lensman57

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Hi all, recently took the plunge on a second hand HEQ5 Pro, i am happy with it but having a few issues with regards to tracking.

1. Polar alignment : I use the polar scope to get Polaris in the centre of the circle, however if i go back to check it later Polaris has moved out out the circle?? Am i doing something wrong? I had assumed the circle would move as time input into handset progressed?

2. - When doing 3 star alignment i find that often i am limited to stars that i can choose from. Last night when doing 2nd star alignment i found that all the choices were in one section of the sky, a part completely out of view from my location, is there anyway around this?

3. Having done a 2 star alignment and polar alignment (i think correctly) i could only get about 30 seconds before star trails emerged which was frustrating! Any reasons for this? Am i doing somehting Wrong?

Thanks.

Hi,

The mount should be level, you need to move the polaris from center the and place it on the circle surronding the + mark. There is a little circle on the larger one it is not necessary to place Polaris in this but what is necessary is to make sure that when you turn the RA axis Polaris stays on the larger circle, if it deviates then you are not aligned properly. If it stays on the circle then you are good for observing and short exposure AP up to a minute or so depending on the FL of your scope. To really get the mount polar aligned you either need to do a drift align routine ( good you have an obsy ) or use the skywatcher's polar align routine after a 2 or 3 star aligment. This is what I do each time I use the mount for imaging.

Regards,

A.G

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CedricTheBrave

CedricTheBrave

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the latest version of firmware on the handset gives you the option to perform a polar alignment if you have performed a two or three star alignment first.

it moves the scope away to a position and asks you to adjust the RA and then moves again and asks you to adjust the DEC.

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Gohan75

Gohan75

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Yes i did see an option for polar alignment under the star alignment settings and wondered what it was?  I have not checked what version the synscan is on so would be worth checking that out also. thanks.

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Russe

Russe

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What I do with my HEQ5 is, I use "polar finder" on my laptop to show me Polaris' position, then I look through the polar scope without turning the little circle to the right position. I then just place Polaris at the position on the little circle, where "polar finder" is showing to put it to.

then I put my scope in the home position manually (using a level I make sure that the dec axis is level to the ground too (holding it on the side).

Then I use "alignmaster" to slew to two stars and correct my polar alignment.

Then I pop in the camera and focus with a Bahtinov on this second star. Then I repeat the alignmaster routine with my camera.

And then ... I slew to my target, stick on a finder guider camera. Calibrate it in PHD and start guiding. Then I start imaging.

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laser_jock99

laser_jock99

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Have you checked to see if your polar scope reticule is properly aligned to the RA axis?

Good description of the procedure here:

http://www.nightskyimages.co.uk/polar_alignment.htm

If the polar scope is not pointing in the same direction as the RA axis of the mount- you won't get PA no matter how well Polaris is centred in the circle!

Mounts DON'T need levelling for good PA btw.

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lensman57

lensman57

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very unlikely that

Can you go into this a bit more, ive not heard of a polar alignment after doing the 2 or 3 star alignment.

Matt.

Hi Matt,

First thing, if you just want to polar align for observing then a simple crude alignment with the polarscope will do, even if the polarscope is not aligned with the axis of the telescope properly. If you wish to align for imaging then no matter how much messing around you do with the alignment using the polar scope is a waste of time. As I said before you have two options, do a manual drift align using stars ( long winded and needing unobstructed view all around) or let the handset do it for you. You  need firmware version 3.35 to be able to do that. This is how I do it., first do a 1 star alignment, for now I use Vega, then  do a 2 star align using Vega as the primary, for  the 2nd one I choose either Alioth or Dubhe for my horizon. Once the Star alignment is done and successful the hand set will show two different sets of figures with Degrees, minutes and seconds, these are the errors in the polar alignment. Press enter and then scroll down to the Polar align routine under alignment and press enter. The handset will give you an option of a star to perform the polar alignment with. I pick Vega for my location as I am centered on it and press enter. The mount will slew to Vega and will ask you to use the direction keys to center the object, do this ( it is best if you invest in an illuminated reticle EP, about £50.00 for  good ones  as accurate centering is the key) and once you press enter the mount will slew to some place in the sky,  the handset will ask you to use the ALT T bolts only  to bring the star as close as possible to the center of eyepiece, do this and make a  note of the position of the star and press enter. The  hand set  will then slew  out again  but this time it will ask you to use the AZ knobs to bring the star close to the location that you made a note of. Once done press enter again and perform another 2 or 3 star alignment ( Mandatory  after each polar align cycle ) with the same satrs as before and go through the routine again. After 2 or 3 cycles, about 5 minutes each, you should be within 30 seconds of error, I find that this is good enough to get a very flat graph in PHD if the set up is well balanced in both RA and DEC axis and this balance is crucial. The good thing about this method and even the drift align  is that you do not even need to see polaris in the first place so long as your initial rough alignment is close enough. BTW 2 or 3 star alignment has nothing to do with polar alignment, it only maps the sky for your location to the mount. If you manage to do a 3 star align then this will take care of the cone error,misalignment of the tube with the axis of the mount. Hope this helps .

Reagrds,

A.G

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Gohan75

Gohan75

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A lot to consider here, my trailing is clearly related to poor polar alignment then. I hadn't realised how complicated polar alignment could be, not that it has put me off as i am very determined to get some great shots having seen the amazing quality of images on this site! Thanks for the advise all, I will be downloading the polar finder software and having a go using the guides that you guys have sent me, now just waiting on some clear skies, not looking good in the UK at the moment! 

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Astrosurf

Astrosurf

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I found the only site that worked was this one http://ca.skywatcher.com/_english/05_service/01_download.php

Many thanks! So I choose V3.35??

The problem i have with star alignment is that most of my horizon is blocked in my garden making it difficult to get a 3 star alignment. Will 2 be sufficient or will this reduce accuracy? 

I only use two and have been advised it's enough. Three sometimes fails for me!

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Astrosurf

Astrosurf

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The trouble is, i find i pick a star that i dont know, and its hidden from view, and then you can't choose another, you have to exit out the entire alignment and start again.

Matt.

I've certainly not figured out a way to get out of that either. Maybe someone has and could help? If that happens to me, I just hope for the best, press Enter and then go to the next star. When I start guiding it's OK. It's just that I then have a job getting my target centred as my handset's not quite 'sure' where it is and is slightley off-target. The finderscope is too magnifying and the object is out-of-view so that's why I use a Telrad on my 200P and a red dot finder on my Megrez. I couldn't be without them now!

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