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How do I have a steadier image for astrophotography?


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My garden is my almost permanent setup, and it's not completely ideal. My overall setup probably weighs 45kg as a own an neq6 sitting on what I call 'crazy paving' the slabs don't move currently but they are thin.
I aim to have a large circular slab set up for chairs in the summer and the telescope at night, without spending thousands on thick concrete and a permanent pier are there any other ways I can have that will improve my setup?
Anything like tripod upgrades? anti vibration feet or something along those lines? thanks.

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You don't have to go mad on concrete to make a pier - a hundred quid or two and some shovelling, or another hundred to pay someone to shovel, and you can make a fairly shallow but functional pier foundation. Concrete chemical anchors or pre-set rebar and you're set for a pier mount (which can literally be a steel tube, optionally filled with sand/concrete, right up to fancy anti-vibration models).

Alternatively, use a wide pad with moderate thickness (say 10cm) and plonk a free-standing pier on it. This will generally perform better than a tripod and be a substantial improvement. Antivibration pads will only help decouple from local noise, generally, like people walking around on softer ground etc etc.

The other thing to consider is - is your "wobble" measureable right now? Is it an issue? Is it actually due to vibration in the ground or is it your mount? Are you guiding? There may be other areas to improve before ground is a limiting factor. I am still using the steel tripod my EQ6-R Pro came with on soft grass, albeit with no local noise sources, and guiding gets me sharp images down to 0.4"/px resolution...

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28 minutes ago, discardedastro said:

You don't have to go mad on concrete to make a pier - a hundred quid or two and some shovelling, or another hundred to pay someone to shovel, and you can make a fairly shallow but functional pier foundation. Concrete chemical anchors or pre-set rebar and you're set for a pier mount (which can literally be a steel tube, optionally filled with sand/concrete, right up to fancy anti-vibration models).

Alternatively, use a wide pad with moderate thickness (say 10cm) and plonk a free-standing pier on it. This will generally perform better than a tripod and be a substantial improvement. Antivibration pads will only help decouple from local noise, generally, like people walking around on softer ground etc etc.

The other thing to consider is - is your "wobble" measureable right now? Is it an issue? Is it actually due to vibration in the ground or is it your mount? Are you guiding? There may be other areas to improve before ground is a limiting factor. I am still using the steel tripod my EQ6-R Pro came with on soft grass, albeit with no local noise sources, and guiding gets me sharp images down to 0.4"/px resolution...

My main issue is tracking, I can only get 10 seconds with PA, my PA isn't 100% because I'm not guiding, recently purchased an adaptor to use my 120asi to get into guiding as a first timer. I just mentioned this topic as the warm weather is around the corner and the garden is due to be done up and the patio is the main feature because I have limited space to walk around at the moment. Just worried that the patio wont be stable enough.

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1 hour ago, Quetzalcoatl72 said:

My main issue is tracking, I can only get 10 seconds with PA, my PA isn't 100% because I'm not guiding, recently purchased an adaptor to use my 120asi to get into guiding as a first timer. I just mentioned this topic as the warm weather is around the corner and the garden is due to be done up and the patio is the main feature because I have limited space to walk around at the moment. Just worried that the patio wont be stable enough.

I'd 100% spend money on guiding before you start mucking around with concrete.

You can probably do better than that on your PA, too, depending on your imaging scale. PHD2's drift alignment is pretty much the gold standard in PA but a Polemaster will get you close enough for rock and roll, especially guided. You'll get a huge amount more value out of guiding and accurate polate alignment than making a super thick patio - guiding corrects for a lot more than movement of the ground, such as mount errors and mechanical inconsistencies more or less anywhere in your system. Polar alignment done with tools like a Polemaster is infinitely more accurate in a short period of time than doing it by eye and requires a lot less crawling under your mount, which is always good!

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While you're at it with your patio maybe consider making some subtle tripod markings / indentations so that you know exactly where to put the tripod feet every time.  I agree with discardedastro - there's no reason I've heard of why your NEQ6 shouldn't be able to track more accurately without the need for a pier.  You may want to look at the mount itself - investigate regreasing the gears and making sure they're meshing the best they can.

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On 06/03/2021 at 09:11, jonathan said:

While you're at it with your patio maybe consider making some subtle tripod markings / indentations so that you know exactly where to put the tripod feet every time.  I agree with discardedastro - there's no reason I've heard of why your NEQ6 shouldn't be able to track more accurately without the need for a pier.  You may want to look at the mount itself - investigate regreasing the gears and making sure they're meshing the best they can.

I was thinking about that, I already have marking at the moment but the patio will go over the top, I'll make them subtle enough so it doesn't ruin the tiles somehow. I'm not sure exactly what the mount is supposed to sound like, wish i could compare with someone on a night out but that's impossible at this current climate. When I try to fix things I always seem to make them worse so I'll leave the gears till guiding is sorted.

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1 hour ago, Quetzalcoatl72 said:

I'm not sure exactly what the mount is supposed to sound like, wish i could compare with someone on a night out but that's impossible at this current climate. When I try to fix things I always seem to make them worse so I'll leave the gears till guiding is sorted.

Some good advice above but if you are worried about the noise your mount is making then you may have an issue there.

Can you make a video (with sound) on your mobile without any background noise?

I should think a NEQ6 should sound similar to a HEQ5 which I have used in the past and when slewing at high speed do make a fairly loud whirling noise, but it should be like a pretty constant noise not really a worrying gears clashing noise (difficult to explain) but when tracking is should be almost silent, if you get close you hear a high pitched ticking noise, around every second or so, but really you have to get close it is quiet.

Are you sure your scope is balanced well in both Ra and Dec ?
Balancing a telescope

And I totally agree with investing in some guiding, but first get the basics right.
You cannot expect guiding to put everything right.
You need all the basics right before you apply guiding. Guiding is just the last step to achieving long exposures and just applies a small adjustment to mount tracking to overcome small issues such as periodic issues of the mount, or issues due to not 100% perfect PA etc.

What scope are you using ? 
Without guiding you should get more than 10 seconds without seeing any real visible star trails when tracking.
This I think does depend to some extent on the focal length of the scope but with a good NEQ6 I should think 30 seconds should easily be possible and even 1 minute if a relatively short focal length (only a guess but I think I managed 3 to 5 mins with 430mm focal length scope on a HEQ5 without guiding) .
I suggest you look into why longer exposures are not possible.

Your mount needs to be stable and a NEQ6 should be stable if all is correct.

So a summary of things to get right before guiding:

  • Scope needs to be well balanced in Ra and Dec.
  • Do not walk around the mount when exposure is in progress if you think the base is dodgy. But a good solid base is ideal (even a flattish lawn or grassed area is better than wobbly pavers or patio) 
  • Polar Alignment needs to be good, I am not saying perfect but you need a polar scope and check you are setting it correctly (Polaris is close to earth axis of rotation but not exact so needs an offset that is time and date dependent) check you are polar aligning correctly with polar scope or use PHD2'2 Drift Alignment or other methods of polar alignment.
  • Is mount 2nd hand - could it be faulty ? If 2nd hand and is making weird noises whilst tracking then this needs correcting. Make a video and post with good sound and no background noises (could do inside during day - just slew using handset at max speed and also put into tracking mode).

If all the above are good then you should be able to get reasonable unguided exposures (I would think anyway) and certainly 30 seconds. Then when unguided exposures are good look into guiding and then 5 mins or more may be the normal but do not expect guiding to take you from 10 seconds to 10 minutes that just does not happen.

I am not expert on Astro-photography by any means and only took it up 3 years or so ago but the above is based on my short experience so far, I think it is correct and hope it helps.

Steve

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On 08/03/2021 at 07:03, teoria_del_big_bang said:

Some good advice above but if you are worried about the noise your mount is making then you may have an issue there.

Can you make a video (with sound) on your mobile without any background noise?

I should think a NEQ6 should sound similar to a HEQ5 which I have used in the past and when slewing at high speed do make a fairly loud whirling noise, but it should be like a pretty constant noise not really a worrying gears clashing noise (difficult to explain) but when tracking is should be almost silent, if you get close you hear a high pitched ticking noise, around every second or so, but really you have to get close it is quiet.

Are you sure your scope is balanced well in both Ra and Dec ?
Balancing a telescope

And I totally agree with investing in some guiding, but first get the basics right.
You cannot expect guiding to put everything right.
You need all the basics right before you apply guiding. Guiding is just the last step to achieving long exposures and just applies a small adjustment to mount tracking to overcome small issues such as periodic issues of the mount, or issues due to not 100% perfect PA etc.

What scope are you using ? 
Without guiding you should get more than 10 seconds without seeing any real visible star trails when tracking.
This I think does depend to some extent on the focal length of the scope but with a good NEQ6 I should think 30 seconds should easily be possible and even 1 minute if a relatively short focal length (only a guess but I think I managed 3 to 5 mins with 430mm focal length scope on a HEQ5 without guiding) .
I suggest you look into why longer exposures are not possible.

Your mount needs to be stable and a NEQ6 should be stable if all is correct.

So a summary of things to get right before guiding:

  • Scope needs to be well balanced in Ra and Dec.
  • Do not walk around the mount when exposure is in progress if you think the base is dodgy. But a good solid base is ideal (even a flattish lawn or grassed area is better than wobbly pavers or patio) 
  • Polar Alignment needs to be good, I am not saying perfect but you need a polar scope and check you are setting it correctly (Polaris is close to earth axis of rotation but not exact so needs an offset that is time and date dependent) check you are polar aligning correctly with polar scope or use PHD2'2 Drift Alignment or other methods of polar alignment.
  • Is mount 2nd hand - could it be faulty ? If 2nd hand and is making weird noises whilst tracking then this needs correcting. Make a video and post with good sound and no background noises (could do inside during day - just slew using handset at max speed and also put into tracking mode).

If all the above are good then you should be able to get reasonable unguided exposures (I would think anyway) and certainly 30 seconds. Then when unguided exposures are good look into guiding and then 5 mins or more may be the normal but do not expect guiding to take you from 10 seconds to 10 minutes that just does not happen.

I am not expert on Astro-photography by any means and only took it up 3 years or so ago but the above is based on my short experience so far, I think it is correct and hope it helps.

Steve

Thanks for taking the time to write that extensive information. I'm almost positive I have all the basics right, I balance my scope in 3 directions (ED80 btw), I was told to have it slightly east heavy. When slewing at max speed it makes a crackling and whirring noise at the beginning and just whirring until I slow it down to stop that's where the crackling begins again otherwise it's just a high pitch hum when tracking.
I bought it brand new in 2016 but I've only used it a dozen or so times, I worry that carrying it around the way I do could damage the mount (cradling like a baby, arm under the largest part, bottom piece hanging downward) I have no carry case they cost just as much as the mount itself!!. I did get the original bolt stuck in the mount day one and had to bend the screw and unscrew it back out which threaded it a little bit, I bought professional az-alt screws and it seems solid so I don't know why that should have an effect. I know I'm polar aligning correctly because the go-to functions more than it used to when I didn't PA the right way(goes right to the objects every time). I have recently upgraded the handset for the first time, I've yet to try it out.
 

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Hi, Yes sounds like you have everything right but with an ED80 you should get much longer than 10 secs with just mount tracking and unguided.

I stress I am still pretty new to all this so not like some of the experts on this site but I initially really struggled guiding even though I had the camera and guidescope (in the end was just me), I cant even remember what the issues were now but couldn't get PHD2 to work in the first few sessions and trying to guide was taking me all night so just decided to get some images rather than messing about with guiding and I got up to 3 mins, with a very similar scope, and no huge star trails (stars not perfect but looked reasonable at normal viewing). 
So with that scope I think you should do similar (walk before run and all that so say aim for 1 min).

Now if the other stuff is right is it just your wobbly patio ????

Do you have a sub longer than 10 seconds you can upload maybe that will give a clue (to someone on SGL at least if not myself).
Above all do not despair, if I can do it then it is not too hard believe me.

Steve

Edited by teoria_del_big_bang
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I agree with the advice about getting things right before adding guiding, there is a fun learning curve when you add a guide camera into the mix. It's superb when you get it working right though. That said, if I were you I would put the guide camera on and run the PHD2 guide assistant to help point you in the right direction. 

 

" I can only get 10 seconds with PA, my PA isn't 100% because I'm not guiding"

Note your polar alignment does not improve with guiding.

 

The noise of the NEQ6 sounds normal, mine is the same.

 

A few bags of postcrete and a metal tube offcut will see you have a pier, I built mine for 10s of £s not hundreds. The best bit is you polar align once and leave it forever, set up is a dream! Note that even with a concrete base, vibrations from walking around will work their way through if you have long focal lengths (same with a camera on a tripod)

 

Per the advice above, regardless of how good you think the polar alignment is, if you are getting drift then that has to be a consideration. 

 

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Just looked back over my early data to make sure my memory wasn't playing tricks on me regarding the exposure length.

Before guiding it looks like 3 minutes was pretty normal for me without significant star trails on images like Orion, Andromeda, Bodes rosette.  The stars are not perfectly round as you would expect when properly guiding but you have to zoom in pretty close to see they are a bit oval.

Below is an unstretched single 3 min unguided image  I took and a significant zoom on the two ringed stars and you can see they are oval but still make a reasonable image at normal frame size. 

image.png.b747b67288972aef4d1cf0e32376ec23.png

 

image.png.b701d51a66c687cb41ca78654dc8c620.png
I think I did do some 5 minutes but cannot find the actual images at moment so maybe there was beginning to show significant star trails and so I limited myself to 3 mins until I were guiding.

So maybe my thoughts about 5 minutes unguided were a bit ambitious but still I really think with your scope and mount 1 to 2 mins unguided should be achievable, there maybe signs of mis-shaped stars very slightly when zoomed in but to look at normal frame size should be pretty good, hopefully somebody will either back that up or correct me if I am wrong.

I think a posted single frame will really help somebody see what your issues may be.

Steve

 

Edited by teoria_del_big_bang
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