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SharpCap 2.9 - Polar Alignment


Andyb90

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1 hour ago, alcol620 said:

Hi Robin

Do you have any suggestions of how this software might be used to polar align a Skywatcher Star Adventurer? Presumably you would need a light weight guide camera and guide scope? Or is there another way?

Thanks for your help

Alec

I have done this with my ST80 and Altair Gp cam. Couldn't get it as close as with a eq5 type mount. But probably still useable. 

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I haven't actually tried capturing any images yet. But I could only get to within "minutes" of alignment rather than "seconds" with the heavier mount. 

I used the SA to familiarise myself with the sharpcap polar alignment prior to getting the bigger mount set up to use it on. 

I have used the SA previously with the ST80 and DSLR though. Thought using sharpcap may help achieve some longer exposure times.  

Edited by Bobby1970
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Well the bits have been ordered and I'm almost ready to try this with my AstroTrac setup where Polar Alignment using the provided PA Scope has been very unpopular and has been the subject of thousands of forum posts. Some users have

engineered the QHY PoleFinder to fit the AT Head but after a successful PA they have to remove it and carefully attach the cameras etc which in itself given its a lightweight setup will push it out of PA.. Now with SharCap and an Altair GPCAM plus

finder scope I'm going to be able to nail this and get plus  20mins  at  300mm  unguided and much more using the guiding using AT's auto-guide capabilities. All I'm waiting for now is the German Postal Service and a few clear nights. I will post my

results as soon as I've processed them. Well done to Robin this is a superb piece of software .

 

Regards

 

Chris 

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10 hours ago, Crose01 said:

Well the bits have been ordered and I'm almost ready to try this with my AstroTrac setup where Polar Alignment using the provided PA Scope has been very unpopular and has been the subject of thousands of forum posts. 

Thousands of posts, really? The AstroTrac polar scope is far from ideal but it is still very useable after some minor tweaking...well the two that I own are and probably "millions" of others.

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Hi Robin

 

Similar experience to Nebula from Madrid.

I PA'd the other night using SharpCap and the software said I was within 10", as I said I ran a 30 minute sub and found little in the way of star trails. Tonight I ran PHD2 drift alignment and had and error of 2.9' (25px) for the AZ adjustment and about 4' (52px) for the Alt adjustment. I am on a pier with and ED80 scope with Atik 383 camera, so I don't think there is any problems with flexing.

Any ideas?

Thanks Alec

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When you are seeing the 'Step 1' UI there are a whole range of options that you can tweak to adjust the parameters for star detection - have a play with those and you will probably be able to fix the problem. If not save a couple of sample frames and send them over.

cheers,

Robin

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Thanks Robin, I also tried running the focus utility, and that saw only Polaris, and only when it was out of focus. Is the chip in the Lodestar interlaced? the stars had that single field look to them when I zoomed in

When I get some more stars I'll grab a frame

Huw

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For guiding, I use an ST80 and QHY5l-IIc. The fov is a little over half a degree, so it's not wide enough for the Sharpcap polar alignment routine. I wondered, though, whether using a 0.5x focal reducer would work. It would bring the fov to over a degree, which is within the spec for the polar alignment routine. Does anyone have experience with this setup?

Robin - Sharpcap is a fantastic program, and I'd like to echo the appreciation others have shown here. Awesome :blob9: :hello2:

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1 hour ago, Ant-33 said:

For guiding, I use an ST80 and QHY5l-IIc. The fov is a little over half a degree, so it's not wide enough for the Sharpcap polar alignment routine. I wondered, though, whether using a 0.5x focal reducer would work. It would bring the fov to over a degree, which is within the spec for the polar alignment routine. Does anyone have experience with this setup?

Robin - Sharpcap is a fantastic program, and I'd like to echo the appreciation others have shown here. Awesome :blob9: :hello2:

I had a go with my ST80, GP Cam + 0.5 focal reducer. On my Star Adventurer it seemed to work ok. 

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@Horwig

I guess you are using the ASCOM driver for the Lodestar - sometimes that can lead to odd effects when the ASCOM driver does things in a way that SharpCap doesn't expect (like some ASCOM drivers claim that colour sensors are really mono, etc). Seeing a frame would help, but if you have a colour sensor but see a mono image and can see a grid pattern when you look at the pixel level, try playing with the 'Debayer Preview' control to force debayering - one of the options should look right colour wise.

cheers,

Robin

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Tried this last night but had a bit of a challenge.

Can get the first image to solve but then rotate around the RA axis and cant ever seem to get the second image to solve. Have tried starting in different places but does not seem to make any difference.

I am manually unlocking the RA and then rotating.

More than likely to be user error but i will be buggered if I can work it out.

Using an AZ-EQ6GT, Altair Starwave 80 with the Altair Starwave 50mm Guider and a GPCAM Colour. Running ASCOM 6.2.0.2774, EQMOD, APT 3.2, Sharpcap 2.9

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Failure to solve in one orientation is usually a result of either not enough stars being detected or hot pixels being picked up as stars and ruining everything.

Best thing to do is to leave the scope in the problem orientation and restart the polar alignment procedure. On the first page you will see lots of controls that allow you to tinker with the star detection parameters. Hopefully playing with one or more of those will get you going. Also have a try with increased or decreased exposure and/or gain. If all that fails then save a frame or two and fling them in my direction.

cheers,

Robin

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I tried sharp cap 2.9 last night with a 50mm canon lens and zwo 120c with 2 second exposures and found it very easy to use......just followed the instructions and nailed polar alignment on my SWSA down to 00.09" took just minutes.

WELL IMPRESSED 

Regards

Graham

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finally managed to get my scope out for a play tonight... fired up sharpcap and (although i've never used it before) within minutes had the best polar alignment i've EVER had...

Robin, you're a goddamn hero :D

wasn't intending to try any AP as, with my personal situation meaning it's been 2 years since i did any, i'm rusty as hell, but fired off a few subs anyway. no guiding whatsoever, balance was questionable and the dew was starting to form at -3 degrees at 2am this morning but what the hell... for totally unguided, i'm really impressed with sharpcaps abilities :D

even managed a small amount of detail my new favourite, Barnards Merope Nebula lol

just a quick stretch and not much else. got a bit of distortion in star images but thats probably down to having to clean the mirror and it needing a bit more poking and prodding to get into shape, but all the software updates/new stuff apart from phd2 (which totally refused to calibrate and failed every time on the clearing backlash phase) worked flawlessly.

m45_zpsuqbfe4z6.png

Edited by Dave_D
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On 06/11/2016 at 21:48, rwg said:

@Horwig

I guess you are using the ASCOM driver for the Lodestar - sometimes that can lead to odd effects when the ASCOM driver does things in a way that SharpCap doesn't expect (like some ASCOM drivers claim that colour sensors are really mono, etc). ...

Robin

The Lodestar is becoming increasing popular for video astronomy using real time frame stacking software (such as Starlight live) and the Lodestar is in widespread use as the guide camera of choice.    Surely Sharpcap's excellent real time frame integration functionality and the new polar alignment routine would both be enhanced greatly by having a specific (non-ASCOM) drivers available for the Lodestar.  Is this possible?

Edited by michaelmorris
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@michaelmorris

It would definitely be possible to add direct support for the lodestar - probably wouldn't even take more than a couple of evenings to do if I had one to play with. Trying to add a new brand of camera without one to work with is a pig of a job - no matter how good the documentation there are always things that aren't included that you have to find out by trial-and-error and that doesn't work well if you are sending repeated trial builds to some long-suffering tester who has the camera.

Of course the other thing that it needs is time, which I seem to be incredibly short of recently :(

cheers,

Robin

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After struggling with an over zealous Windows Defender I finally managed to download the ASCOM drivers for the Lodestar.  After configuring the ASCOM drivers for the Lodestar, Sharpcap recognised my Lodestar 2. 

Wow, this polar alignment tool is seriously neat. Following the on screen instructions (something I didn't do the first two times I used it :BangHead: ) it worked like a dream.  I had my mount aligned really well within about 1/2 hour.  Even with my Lodestar 2, I still had to use 7 second exposures, but it worked.  The next time it gets used it should be a lot quicker.  

Thanks for a great program Robin.

Edited by michaelmorris
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