Starsense or better mount - can't decide!

[RobertI]

I'm planning to do as much EAA/Video as I can this winter. I currently have a CG5 which I operate from inside the house - it does the job, but polar alignment plus goto alignment takes a little while and it is potentially pretty noisy for the neighbours. I'd like to simplify and speed up my setup time, and am thinking I have two options:

1. Add Starsense to my existing setup - about £360 including special cable required for CG5 - I have been told this produces accurate enough alignment to get objects onto the tiny chip of my Lodestar and should speed up setup time, also believe I will have to find an alternative to Nexremote for remote control of mount. I feel there are a few risks with this approach.
2. Buy a nice quiet modern altaz/eq goto, such as the AZ-EQ5 - about £950 (or £820 clearance on FLO) - easier to align than an EQ, can use EQ Mod for remote control, nice and quiet, but no Starsense (cannot stretch to new mount and star sense...yet), possibly not saving as much setup time as with option 1 - I would need to sell a couple of my lesser used scopes as well as my current mount to fund this.

Head says StarSense, heart says new mount.  Any sage advice from the forum to help me decide would be appreciated! 

Rob

 

[Handy_Andy]

I've had a starsense on my AVX since the get go and tbh it isn't that much faster than doing two star alignment and adding a couple of calibration stars. The main advantage to star sense is that it's far less involved when setting up once I've polar aligned and gives me a couple of minutes to faff around with the gear I have. There is also a drawback when switching scopes, each time you swap telescope you will need to re calibrate star sense to match the center of your FOV. It doesn't take much time but enough that you would be better off aligning off your handset instead.

[BlueAstra]

Check the usual second hand sources. Starsense units come up for sale from time to time, so that might help with the budget. That's how I got mine.

 

 

[CrashEd]

Yep, mine is still available in the classifieds if you are interested (thanks BlueAstra). I've gone from an Evo 6 to an AZ EQ-5 GT mount, but I've bought the Skywatcher version of Starsense as it speeds up the process no end. 

Re swapping scopes; you can save up to 10 calibration profiles in the handset negating the need to re-calibrate everytime you swap. The StarSense mount is repeatable enough to just swap the unit over and load the appropriate profile. 

[Thalestris24]

Hi Rob

How much of the sky can you see? I live in a 2nd floor flat and am effectively restricted to imaging via an open window. It's far from ideal and, as well as a limited view, the thermals pay havoc! I can only see east with my 115mm apo on an avx. I just drift align in alt using phd2 and point the mount true north with a compass app (Takes 10-15 mins). Small errors in Az PA have little effect when only imaging in the east. I can see a span of about 78 to just over 100 deg in Az. I'm lucky in that I can leave everything set up so only do PA occasionally. I'm usually slightly off target but use platesolving to get targets dead centre.

Louise

[newbie alert]

The starsense won't help you with polar alignment..yes it has the ASPA feature on the handset  but it's not as accurate as proper PA..

I was highly disappointed with mine and has put me off celestron as a brand because of it..

[CrashEd]

25 minutes ago, newbie alert said:

The starsense won't help you with polar alignment..yes it has the ASPA feature on the handset  but it's not as accurate as proper PA..

I was highly disappointed with mine and has put me off celestron as a brand because of it..

That's funny, I love mine and have bought one for my new mount. Different strokes and all that. I find it far better that the Starwatcher HC and setup is much easier. Guess I'm lazy! (or just like to do other things whilst it's doing its thing). 

[Thalestris24]

Yeah, as I understand it the Starsense just helps you align stars, doesn't do PA. But it's redundant if you can use platesolving.

Louise

[CrashEd]

8 minutes ago, Thalestris24 said:

Yeah, as I understand it the Starsense just helps you align stars, doesn't do PA. But it's redundant if you can use platesolving.

Louise

Yep, that's how I understand it. 

What carries out your plate solving? Do you require a separate camera or do you use your imager/guidescooe?

[RayD]

Starsense is for star alignment only and will not do PA. If you do visual it is very good and makes alignment a doddle, but for imaging it isn't necessary as you can plate solve. For plate solving there are various methods. I use SGPro with Pinpoint and this uses your main imaging camera to take a sub, check this against where you want to point (planetarium software or coordinates etc) and then moves the scope to that position and checks again. You can synch this position with you planetary software. 

[Thalestris24]

8 minutes ago, CrashEd said:

Yep, that's how I understand it. 

What carries out your plate solving? Do you require a separate camera or do you use your imager/guidescooe?

I just use Astrotortilla. It takes an image via the imaging camera using APT, solves it, then moves the mount to where Stellarium is actually pointing, then does a second exposure to confirm. Exposures are only 2-3 secs so the whole thing takes seconds. Once set up it makes centering targets very quick and easy. Some people use 'platesolve' which APT supports.

Louiss

[newbie alert]

2 hours ago, CrashEd said:

That's funny, I love mine and have bought one for my new mount. Different strokes and all that. I find it far better that the Starwatcher HC and setup is much easier. Guess I'm lazy! (or just like to do other things whilst it's doing its thing). 

Yes, we are all different.. but had a totall nightmare with mine..and wasn't ever going to do what I wanted it to do..as in polar align..

I only ever got it to align once..and then it clouded up!!

[RobertI]

Thanks @Thalestris24, @RayD, @CrashEd, @HandyAndy, @BlueAstra and @newbie alert.

To answer a few questions and clarify, my main goal is really to get observing with the camera as quickly as possible, and reduce the likelihood of problems. Typical problems include:

1. I cock up the polar alignment (I'm pretty adept but still get it wrong sometimes) and I don't find out until I realise that tracking is not good. Occasionally the polar scope becomes off-centred too, so I feel I have to check that each time too, adding to the setup time.
2. Goto alignment does not work first time. Usually I do manual alignment indoors using a homebrew electronic finder I have, but sometimes initial alignment gotos are way off for some reason, and alignment stars are not even in the field of view of the electronic finder, so I have to start again. Also manual alignment can take time as you have to select alignment stars which you can easily identify and you feel are in the right place, just a bit tedious.
3. The gotos are not quite good enough and do not get the object in the field of view - this is terminal as I have no way to find the object.

So I believe an altaz mount would solve problem 1, Starsense would solve problem 2 and platesolving through the main camera would solve problems 2 & 3. 

If I am being honest problems 2 and 3 are the biggest issues.

Although I like Starsense, I do worry about it's ability to get accurate enough alignment so that the gotos can get the image into a tiny camera chip. Also not everyone seems to get on with it. It would appear that platesolving using the main cam is the answer, but how quick and easy is it and how well will it work with a tiny field of view? Do you need a fast computer? I have an i3. 

Sorry if I have rambled, but it helps to talk it throug, so thanks for being patient! 

[RayD]

14 minutes ago, RobertI said:

Thanks @Thalestris24, @RayD, @CrashEd, @HandyAndy, @BlueAstra and @newbie alert.

To answer a few questions and clarify, my main goal is really to get observing with the camera as quickly as possible, and reduce the likelihood of problems. Typical problems include:

1. I cock up the polar alignment (I'm pretty adept but still get it wrong sometimes) and I don't find out until I realise that tracking is not good. Occasionally the polar scope becomes off-centred too, so I feel I have to check that each time too, adding to the setup time.
2. Goto alignment does not work first time. Usually I do manual alignment indoors using a homebrew electronic finder I have, but sometimes initial alignment gotos are way off for some reason, and alignment stars are not even in the field of view of the electronic finder, so I have to start again. Also manual alignment can take time as you have to select alignment stars which you can easily identify and you feel are in the right place, just a bit tedious.
3. The gotos are not quite good enough and do not get the object in the field of view - this is terminal as I have no way to find the object.

So I believe an altaz mount would solve problem 1, Starsense would solve problem 2 and platesolving through the main camera would solve problems 2 & 3. 

If I am being honest problems 2 and 3 are the biggest issues.

Although I like Starsense, I do worry about it's ability to get accurate enough alignment so that the gotos can get the image into a tiny camera chip. Also not everyone seems to get on with it. It would appear that platesolving using the main cam is the answer, but how quick and easy is it and how well will it work with a tiny field of view? Do you need a fast computer? I have an i3. 

Sorry if I have rambled, but it helps to talk it throug, so thanks for being patient! 

Platesolving, like everything in AP, takes a little getting used to and a little practice, but once you've downloaded the catalogues and have it running it is very easy indeed.  Accuracy is as good as it gets as you use it to sync with your planetarium so it is very accurate (within a few pixels if you want).

i3 is fine.  The catalogues can be a fair size (around 70mb or so) but it isn't very hard going on the processor.

[Thalestris24]

Hi again Rob,

I'm afraid I think I kind of mentally skip over your EAA intentions! You've not mentioned guiding? I'm also not sure which scope you're using? I assume you're using the Lodestar for the EAA? That will give you a tiny fov with any scope. That will make it difficult to get on target and to stay on target. You might be better off getting another camera with a larger fov and use the Lodestar for guiding? I think there are some other cmos cameras out there with fairly high qe. I suggest this cos I've thought of doing it myself

Louise

ps platesolving might be difficult with a very small fov

[CrashEd]

I have an Atik Infinity and I use the Starsense with it. It places the target bang in the centre every time - pretty faultless. Not sure why others have had issues, but it's not designed for polar alignment as far as I know. You can do an ASPA (All Star Polar Alignment) with it, but I have no idea how accurate it is. Probably better with a Polemaster or similar. I'm sure I'll move on to plate solving at some point, but I'm keeping it simple for now.

[RobertI]

On 11/3/2017 at 21:38, RayD said:

Platesolving, like everything in AP, takes a little getting used to and a little practice, but once you've downloaded the catalogues and have it running it is very easy indeed.  Accuracy is as good as it gets as you use it to sync with your planetarium so it is very accurate (within a few pixels if you want).

i3 is fine.  The catalogues can be a fair size (around 70mb or so) but it isn't very hard going on the processor.

Thanks Ray, it sounds really good, I think I need to have a go to really see if it works for me. Another BIG advantage I guess is that I can use any of my scopes and not worry about having to switch the electronic finder/starsense accessory. Presumably would need different catalogues for the different FOVSs? My setup involves Nextremote s/w controlling the mount and sometimes Stellarium talking to the mount. Would Astrotortilla or SGPro work seamlessly with that setup?

On 11/3/2017 at 21:38, Thalestris24 said:

Hi again Rob,

I'm afraid I think I kind of mentally skip over your EAA intentions! You've not mentioned guiding? I'm also not sure which scope you're using? I assume you're using the Lodestar for the EAA? That will give you a tiny fov with any scope. That will make it difficult to get on target and to stay on target. You might be better off getting another camera with a larger fov and use the Lodestar for guiding? I think there are some other cmos cameras out there with fairly high qe. I suggest this cos I've thought of doing it myself

Louise

Hi Louise, I don't guide as most exposures for EAA are less than 30 seconds, so one less problem. As for scopes I use three scopes, the C8@F10, the RC6@F4.5 and the 72mm@F3 depending in the object. The RC6 is the one I use most but I do switch, so anything that makes that easier would be good. Good suggestion about the larger chip, that is something else on the list, I guess the downside is the potential coma like effects on the bigger chip at the massive reductions I use...another unknown!

On 11/3/2017 at 21:40, CrashEd said:

I have an Atik Infinity and I use the Starsense with it. It places the target bang in the centre every time - pretty faultless. Not sure why others have had issues, but it's not designed for polar alignment as far as I know. You can do an ASPA (All Star Polar Alignment) with it, but I have no idea how accurate it is. Probably better with a Polemaster or similar.

That's really good to hear, and very reassuring. Which scope do you use and at what F ratio?

[Thalestris24]

2 minutes ago, RobertI said:

Thanks Ray, it sounds really good, I think I need to have a go to really see if it works for me. Another BIG advantage I guess is that I can use any of my scopes and not worry about having to switch the electronic finder/starsense accessory. Presumably would need different catalogues for the different FOVSs? My setup involves Nextremote s/w controlling the mount and sometimes Stellarium talking to the mount. Would Astrotortilla or SGPro work seamlessly with that setup?

Hi Louise, I don't guide as most exposures for EAA are less than 30 seconds, so one less problem. As for scopes I use three scopes, the C8@F10, the RC6@F4.5 and the 72mm@F3 depending in the object. The RC6 is the one I use most but I do switch, so anything that makes that easier would be good. Good suggestion about the larger chip, that is something else on the list, I guess the downside is the potential coma like effects on the bigger chip at the massive reductions I use...another unknown!

That's really good to hear, and very reassuring. Which scope do you use and at what F ratio?

Hi

The guiding suggestion was simply to keep on target. The longer the focal length, the quicker you'll drift off target, however good your PA might be. I have a qhy minicam5s on an 80mm apo (on an heq5 syntrek with belt mod - very smooth and quiet!) and guided with an AA GPCam. They work quite well together though I've not been able to get platesolving to work with the minicam5s. I've thought that was because of the small fov but it might just be a catalogue issue, so it might yet work if I fiddle with it! Still, I get good images with the cooled cam. I have very little time these days and the Glasgow weather has been abyssmal! The zwo ASI178mm looks a possible alternative camera, there may be others

Louise

[Thalestris24]

Just thought I'd post this link - it's a handy/useful zwo cmos camera guide

[RobertI]

26 minutes ago, Thalestris24 said:

Just thought I'd post this link - it's a handy/useful zwo cmos camera guide

What a useful guide, thank you! I must admit that I have been bamboozled by the ever changing model numbers of ZWO. I know that the ZWO CMOS cameras are becoming very popular for EAA, and I think Sharpcap now does live stacking and is pretty good for EAA (though not as good as Atik and SX s/w which have camera & software packages dedicated to EAA). A bigger chip is definitely on the list though, thanks for the advice.

[CrashEd]

1 hour ago, RobertI said:

That's really good to hear, and very reassuring. Which scope do you use and at what F ratio?

C8 F10 mainly but also an ES ED80 F6 ?

[RayD]

10 hours ago, RobertI said:

Thanks Ray, it sounds really good, I think I need to have a go to really see if it works for me. Another BIG advantage I guess is that I can use any of my scopes and not worry about having to switch the electronic finder/starsense accessory. Presumably would need different catalogues for the different FOVSs? My setup involves Nextremote s/w controlling the mount and sometimes Stellarium talking to the mount. Would Astrotortilla or SGPro work seamlessly with that setup?

I use SGPro and its plate solving features are excellent.  Yes it will work fine with your different set ups and, as you make different profiles for each, the FOV is set in each so whichever kit you are using you select that profile and away you go.  It sounds far more complicated than it is.  I was a bit daunted before using it myself, but now can't express enough just how simple it is but how useful also, particularly if you use something like SGPro which has all the features of plate solving and acquisition rolled in to one place.

I think SGPro still do a trial version so worth trying it with Plate Solve 2 (free) and see if it works for you.  Nothing to lose.

[allotmenteer]

I'm looking at the Starsense accessory too with the aim of simplifying trying to take basic shots. The odds of achieving good alignment, getting the tracking software running well (PHD) and sorting out focus and capture software settings before the dew sets in are usually quite long for me.

Can anyone comment on whether Starsense removes the need for the tracking element - I've read several threads and some seem to comment that the image is stable enough without and others (in this thread too) refer to retaining the tracking option. I have been trying to use a finderscope with a camera to track with so guess if the finderscope goes I'll lose this anyway?

Any help welcome before I spend the money!

Thanks

[RayD]

2 hours ago, allotmenteer said:

I'm looking at the Starsense accessory too with the aim of simplifying trying to take basic shots. The odds of achieving good alignment, getting the tracking software running well (PHD) and sorting out focus and capture software settings before the dew sets in are usually quite long for me.

Can anyone comment on whether Starsense removes the need for the tracking element - I've read several threads and some seem to comment that the image is stable enough without and others (in this thread too) refer to retaining the tracking option. I have been trying to use a finderscope with a camera to track with so guess if the finderscope goes I'll lose this anyway?

Any help welcome before I spend the money!

Thanks

No Starsense will do nothing at all for your tracking or guiding.  It will only help you with an initial star alignment for Goto's.

To get good tracking you need to work on your polar alignment, which is effectively pointing the RA axis of your telescope at polar north, so nothing to do with star alignment (Starsense) which just tells the mount where the telescope is actually pointing, as it is probably not perfectly aligned with it (cone error).

[allotmenteer]

Thanks, I have a CPC800 so guess this isn't as relevant as with other mounts. Wasn't sure if the camera arrangement was giving dynamic feedback to the mount as per with PHD but not from your reply.

Guess the saved 15 mins and reduced faffing around might be worth the cost, particularly when its all done and then loose power and have to start again!

Thanks