Help needed on astrophotography with the Skywatcher 5"

Bergkamp_ · Post by **Bergkamp_** » Sun Feb 20, 2005 10:25 pm

I got a 5" skywatcher setup.. canon a80 + the adapter ring to attach it to the ep.. so what are the things still needed for good long exposure astrophotography beside taking pic of the moon.. my tripod does not have a motor..

Post by **weixing** » Sun Feb 20, 2005 10:57 pm

Hi,
Get a RA motor drive.

Have a nice day.

kayheem · Post by **kayheem** » Sun Feb 20, 2005 11:37 pm

Hi,

I don't think the A80 will be suitable for long exposure photography.

The Canon 350D is coming out soon, so the older model 300D should be quite cheap to get 2nd hand.

If you really want long exposure, get dual axis drives instead of just RA drive.

Kay Heem

Post by **weixing** » Mon Feb 21, 2005 12:06 am

Hi,

If you really want long exposure, get dual axis drives instead of just RA drive.

A dual-axis motor drive is practically useless in EQ3-2 mount... I used it before. My unit take around 40 second to change direction at the slowest speed mode, which is basically the speed need for guiding.

So my advice is, get a RA drive and do a good polar aligment. Forget about DSO imaging, try out planet imaging to gain experience in polar alignment, focusing and image processing.

When you got the extra cash, get a DSLR to do some short exposure(< 1min) astrophotography on those bright DSO to gain more experience. When you got more extra cash, change to a better mount.

Have a nice day.

Bergkamp_ · Post by **Bergkamp_** » Mon Feb 21, 2005 1:14 am

hmm.. canon a80 can open shutter up to 15 secs.. hmm teach me.. if astro stack can help.. if i wonder if etx wif goto.. can solve my problem of the tracking of the things i want to take.. oya.. canon a80 wif batt is pretty heavy.. i wonder if etx gear can take the weight..

Post by **Airconvent** » Mon Feb 21, 2005 1:58 am

Bergkamp_ wrote:hmm.. canon a80 can open shutter up to 15 secs.. hmm teach me.. if astro stack can help.. if i wonder if etx wif goto.. can solve my problem of the tracking of the things i want to take.. oya.. canon a80 wif batt is pretty heavy.. i wonder if etx gear can take the weight..

Hi Wee Ern,
The ETX can track pretty ok if you can polar align it and run on one motor.
That's what the ETX90RA can do very well. However, that's going to be very difficult here since we don't normally see Polaris and you need skill to drift align.
For the ETX goto, it tracks via 2 axis. This is acceptable visually but for astrophotography, the tracking error would blur any long exposure images you take.

You would probably benefit more from an equatorial mount if you want to take long exposures....

Post by **weixing** » Mon Feb 21, 2005 2:21 am

Hi,
As what I mention, get a RA drive and learn how to do polar alignment using drift star alignment... it is not difficult, just take your time to do as accurate as possible. The last time I do it, I took around 45min to do the drift star alignment... not up to standard, but good enough for 1 min unguided prime focus exposure.

Anyway, try image M42 first, you should took as many shot as possible, stack it using photoshop or registrax and you should able to get a decent image of M42.

Happy imaging and have a nice day.

Bergkamp_ · Post by **Bergkamp_** » Mon Feb 21, 2005 2:24 am

thanks alot for both help.. =)
and cool! u can remember my chinese name =P