To motorise myself.....

[laurieo]

Hi

Some advice please. I'n new to this game and, once I work out how to drive my 'scope my plan is to do some basic astrophotography. I don't really see myself worrying too much about any deep space objects - too much light polution where I live ayway - but want to get some interesting pictures of the moon and planets, and maybe an interesting galaxy or two if my telescope is powerful enough to see any.

I know I need to motorise my mount but am confused... I have a skywatcher EQ3-2 equitorial mount, but what sort of motors do I need? The options are a single-axis RA motor, duel axis motor or the "enhanced" duel axis (which, as far as I can see has a socket for a alignment/tracking camera but my budget won't stretch to one of those).

Obviously, like everyone else I'm conscious of the cost so don't want to spend more than is appropriate.

So, based upon what I want to achieve can you please advise me or give me pointers on whether the single-axis motor will do the job or it would be sensible to go for the dual axis variety

Thanks

[David Frydman]

Hi,

For short time exposures a single RA drive will do if the mount is well aligned.

However, I don't know the size and focal ratio of the scope or how sturdy the tripod is.

With modern cameras high ISO is easily used.

I used to get good planet photos with one second exposures, 200 ASA film and f/72 with eyepiece projection on an SLR.

Now people use video images and stacking.

It may be more complicated for galaxies, but dedicated astrophotographers will help here I hope.

Regards,
David

[Brian]

Hi and Welcome!
Over the last 30years I have used 3 different setups for (mainly) solar-system astro imaging. Each of these use a polar-aligned EQ mounting with a motor drive in RA .
I have a 102mm f5 refractor on an EQ-1 with simple motor drive to RA and a manual adjustment to Dec. I have used a 203mm Dall-Kirkham Cassegrain on a Vixen Super Polaris mounting with RA motor drive and manual Dec adjustment. My current setup is a Meade 250mm LX90 SCT mounted on a polar wedge. The LX90 has motor drives to RA and Dec axes .

All three setups have been used successfully for solar-system imaging using webcams. I monitor the webcam output in real-time on a computer screen . If the mounting is fairly well polar aligned then the image will only slowly drift out of the field of view. In this case a small adjustment with the motor drive in RA or the Dec drive by hand will realign the target and allow more video to be recorded. I adjust the target between, not during, these videos.

I have also used the Cassegrain on the Super Polaris mounting as a guide scope for a "piggy-backed" 35mm camera and 200mm telephoto lens to get 5-minute exposures of some constellations (wide-field). In this case the telescope was used as a guide-scope, with me doing the guiding by eye . I used an illuminated guiding diagonal with built-in x3 barlow (by Vixen). At high-power I could make tiny adjustments to keep a target star centered without stopping the drive. The tracking resolution was much greater than the resolution of the camera so stars recorded as "dots" rather than "lines".

So yes it is possible to get good planetary, lunar and ( with safety filters ) solar images with just a motorised RA axis.

Regards,

[laurieo]

Thanks for this...

So, I'll first make sure I can properly run my camera remotely (I'm sure I can. It's an Olympus Pen) then go for it.

If it's ever a clear night and I do some pictures, I'll post them on the forum

[jeff.stevens]

Look forward to seeing your photos, and hearing how you get on setting it all up.

Best wishes, Jeff.