first telescope & camera

[Joel7292 (Joel)]

Hi everyone, I have a Star Adventurer 2i Pro mount and am thinking of getting a REDCAT 51 and an ASI 533 MC Pro camera as my starter scope and camera. These are around the half maximum weight range for my mount. Does anyone have any advice on my choice. My interest is in DSO's.

[OzEclipse (Joe Cali)]

You have made a good choice in terms of payload to mount rating weight.

The only downside is that the image scale for that combination is 3 arc sec per pixel which might not combine well with the large PE of these mounts that vary greatly from unit to unit. A range of 30-90 arc sec gets quoted.

This measurement was almost 90"
https://www.star-watcher.ch/equipmen...eriodic-error/

Phil Hart measured 50"
https://philhart.com/content/star-ad...f%20the%20worm.

I can't find an example but I remember reading some quoting 30".

Thirty arc seconds is a streak of 10 pixels if your exposure is anywhere around 5 mins or 1/2 of the worm period. A ninety arc second PE is 30 pixels of streak.

Are you going to autoguide or use lucky imaging? At 250mm, your lucky imaging subs might need to be very short.

Photos I have seen with the Redcat 51 look pretty sharp with some blue haloes around brighter stars.

See REDCAT 51 examples from Astrobin

[Bassnut (Fred)]

Definitely won't work. The Star Adventurer 2i Pro mount is great with say a DSLR and 50mm lens or wider. The scope and cam you mention are a good start for WF DSO, but with a different mount. ioptron CEM26 perhaps.

[Sunfish (Ray)]

I have the older star adventurer and have used that with a heavy 800mm or a 200mm as a travel mount.

The heavier lense is not ideal unless you spend a lot of time setting it up to prevent slip and get balanced but it can be done by adding additional counterweights. So i think the red cat would work at around 1.5kg for the scope. The limit of exposure is usually about 40 sec or less with good polar alignment so you are limited to the bigger brighter objects. These are also easier to find.

If you check cloudy nights there a lot of people using heavy lenses with star adventurers and additional weights and getting good results.

[Crater101 (Warren)]

Originally Posted by Sunfish

If you check cloudy nights there a lot of people using heavy lenses with star adventurers and additional weights and getting good results.

As someone who is only beginning to scratch the surface of astrophotography, would something like the Williams Optics Z61 work with that setup? Just a thought. I've been considering a similar setup.

[AstroViking (Steve)]

For what it's worth, I have successfully used a Sky Watcher EvoStar 72ED on my Star Adventurer.

Caveats - the exposure times were very short (no more than 15 seconds, but that was due to light pollution) and the polar alignment MUST be spot-on.

The hardest part is finding your desired target and getting the scope aimed correctly.

Cheers,
V

[Sunfish (Ray)]

Yes finding the target is the hard thing and Stellarium on your phone in dark mode helps.

The Williams 71 plus camera would be around 3kg I think so that would work on a star adventurer if you kept exposure short 20-30 seconds , had a south view for good polar alignment and would be an ideal cheap travel setup.

Some cameras and GPS devices can give a south point accurate enough for very short exposures combined with an electronic level for altitude and this helps in the field to find octans.

[Todo43 (Lachlan)]

Very interesting to hear the opinions on this topic. I started on the Star Adventurer 2i and spent most of my time on it using a Canon DSLR and a 200mm camera lens (5.89 arc second/pixel). I wasn't auto-guiding and yet I found I got quite good results from how I felt back then. Attached are a couple of my best images, all of which have approximately 2 hours of integration time.

Most of my images have got exposures of 120-240s. Yes, they had some trails, but it was better than sitting at 5s exposures without the tracker. I was happy with the results back then. I now look back and go "ahh! Why did I choose to do that!"

Let it be known that I spent a while nailing polar alignment and with my U18 eyes, I was able to spot the octans from my Bortle 5 skies and used the polar scope illuminator to align them to the markings on the glass.

Hope this advice helps!