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sulaco

DIY Polar Align Camera...Sort of

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I've often wanted to get a camera attachment of some sort to make a a DIY Polar alignment method and  noticed a review of the SharpCap 2.9 Polar alignment function, so I ordered an adapter for a well known brands Polar Camera to fit my HEQ5.

I then made a separate adapter on the lathe with a 1/4" x 20 thread for a camera tripod screw that would then fit my ASI120mm and then a Pentax takumar 85mm 1.8 lens with a spacer, Bob's your uncle it works a treat so far.

I need to try it again but my alignment was so quick and my PHD2 graph much flatter.

Not as compact a package as a purpose built camera but works well with Sharpcap 2.9.

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Edited by sulaco
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Neat job!  I was going to go this way until I found that SharpCap works just as effectively with my ASI120M coupled to a 60mm finder/guide scope attached to the existing finder mount.  Just seemed an easier thing to do I'm not good at mechanics!)

 

 

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2 hours ago, kaito83 said:

HI this is good but you have centralize the camera to your mounts axis

Not so. The routines used by Sharpcap and Polemaster allow for off centre camera installations - as long as the camera is attached firmly and stays fixed in relation to the mount.

 

 

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When you are looking at things many light years distant, a sideways offset of 30cm really doesn't matter ;)

cheers,

Robin

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Am I missing something here, shouldn't the mount be aligned to the polar axis through the mount axis. Does Sharp caps design need it to be mounted off central?

 

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2 hours ago, sulaco said:

Am I missing something here, shouldn't the mount be aligned to the polar axis through the mount axis. Does Sharp caps design need it to be mounted off central?

 

If you were using the camera to augment the existing polar scope (so that you didn't have to kneel down) then the polar scope would have to be perfectly aligned with the rotation axis in RA.

However SharpCap and PoleMaster use a method to determine where the mount is pointing by rotating the mount in RA. So as long as you are pointing in the general direction of the NCP and rotating in RA keeps the NCP in the field of view of the camera it doesn't matter if it is perfectly aligned with the mount or offset...

So in answer to your question, no it doesn't have to be aligned but it doesn't cause any harm if it is.

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Hi Sulaco - i was looking at doing something very similar with the ASI120mc. Looks a nice professional job!

I bought the ZWO CS Lens 2.8mm-12mm f/1.4 lens also. Do you think that would work?

I have a hobby cnc machine that I sued to make a bung style mount for my Ioptron ZEQ25 and it works great, just need to know if the ASI lens would work.

If not, do you have any more info on the spacer for the pentax lens? I can pick one of those up from Ebay for £60, which is a hell of a lot cheaper than the QHY polemaster.

Thanks


Dave.

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Hi Dave,

Thanks, not sure how accurate that would be I'm sure the pole master lens has a pretty short focal length working in conjunction with it's software but when using the Sharp cap software a longer focal length is better from what I understand.

I'm using a Takumar 85mm 1.8 and it works well, StuartJPP mentions above that simply attaching the guidecam off axis on the scope works just as well. 

I'm a Jeweller so I just love fiddling about on the lathe, I find it a nice little attachment though.

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Thanks again Sulaco. You mention a spacer for the Takumar lens - do you have any link to that or the name so I could look at purchasing?

Does the spacer fit on the lens and then that connects to the ASI120 or does the lens connect direct to the ASI120?

I'm the same with the cnc machine - love designing & tinkering - hence why I made the adaptor for the ZWO.

Edited by Geordieboy46

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Hi Geordieboy,

You know, I've no idea why I wrote spacer as there isn't one just the polemaster attachment and the turning I made. Sorry for the confusion.

Campbell

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