Aligning camera in RA and Dec

[SteveBz]

I'm trying to align the camera in RA and dec on my Newtonian so that up is North.  This is what I've done, do you think it's correct?

1)  Polar align scope.

2) Align eyepiece tube with camera mount on telescope mounting rings like so:

3) Mount camera upside down to invert image like this:

That's it. 

Do you think that is right?  How should I test it?

Thanks

Steve

[billyharris72]

I would think if the tube is pointed at Polaris and the tube rotated so that the eyepiece is facing straight up then you can just plug the camera in "square" (so to speak) and the alignment should be pretty close. In that respect I think what you've done looks mostly right.

However - and here is where I might get it totally wrong - I think the camera needs to be the other way round (i.e. right way up) since a camera lens, like a Newtonian tube (or a frac used straight through), gives an inverted image. So the camera should "turn it around" for you.

Try it and see.

Billy.

[SteveBz]

Hi Billy,

Well it's an easy idea to test.   It sounds right to me. I did try to test my original idea it out yesterday, very quickly between rainstorms, but I got confused about the results when I realised that the familiar "face" of the Moon does not point North anyway!!

Next good forecast is for Wed night.

I'll post back when I've tried it again.  I have a few other tests to do too, like focussing, PC connectivity and so on.

Thanks,

Steve.

[wimvb]

I have my camera on the mount side of the scope. Since the camera is quite heavy, balance isn't affected as much when the scope rotates in RA during imaging.

[SteveBz]

3 hours ago, wimvb said:

I have my camera on the mount side of the scope. Since the camera is quite heavy, balance isn't affected as much when the scope rotates in RA during imaging.

You mean on the underside when pointing North?  I may try them both.

Thanks

Steve.

[wimvb]

Yes, "hanging" when in Park position. And for some reason I usually align RA with the long side of the sensor. But ideally that should depend on the target.

[iapa]

On ‎12‎/‎12‎/‎2016 at 22:16, SteveBz said:

You mean on the underside when pointing North?  I may try them both.

Thanks

Steve.

If you take an image at night, you could plate solve with Astrotortilla - it shows the rotation of the image, and whether it is 'lipped' or not.

[iapa]

Oh, another thought before you 'lock' it down.

You may need to check your balance - AstronomyShed video explains how to do this.

Reason I mention is if the tube needs to be rotates in the rings, you may need to adjust the camera's rotation to bring it back to 'true'.

 

 

 

 

[ollypenrice]

I agree with Wim. Most experienced New imagers have the camera hanging when pointing at Polaris. It consderably reduces the amount of counterwight for one thing. I'd rotate your tube 180. As for orientation, just take a short sub while pointing at somthing obvious like M42 and compare it with the charts. A 180 rotation can be doine in software in a click. Not all capture programmes give you the image the same way up, either. Nebulosity presents captures normally for me but saves them flipped horizontally and rotated 180. Lord knows why!

Olly

[Owmuchonomy]

Aim at a bright star, switch on live view on the camera screen and use the N, S, W, E keys on the handset to determine orientation.  If you have EOS utilities you can use that instead and switch on the reticle function.