Astrotrac Adventures

[seeker372011]

Of late all the focus and attention of those who like their imaging gear small (relatively) inexpensive and highly portable has been (deservedly) on the Vixen Polarie.

I have one and love it.

However, I have been having great fun with my Astrotrac which I find is really capable and ticks all the boxes (as far as I am concerned in terms of simplicity, lack of hassle and portability)

I have teamed the Astrotrac with a Borg 45ED (with a 0.8 focal reducer) and a Canon 450D. Occasionally, Ill just use the canon kit lens

I have two ED telescopes, two mounts a CG5 meant be the portable mount and an EQ6), two cooled QHY CCDs and for the past year have not touched any of these, so clearly I must like the Astrotrac. (and Polarie which I use when I cant use the Astrotrac for any reason :))

I plan to image the Messier catalogue with the astrotrac, which given how infrequently I get out is a long term project.

Here are some results to date



http://www.flickr.com/photos/91784720@N00/7261242564/sizes/o/in/photostream/

http://www.flickr.com/photos/91784720@N00/7261243694/sizes/o/in/photostream/


http://www.flickr.com/photos/91784720@N00/7465665776/sizes/o/in/photostream/

http://www.flickr.com/photos/91784720@N00/7465663500/sizes/o/in/photostream/

http://www.flickr.com/photos/91784720@N00/7609173542/sizes/o/in/photostream/

http://www.flickr.com/photos/91784720@N00/8367083340/sizes/o/in/photostream/

if you cant be bothered clicking on links here are are smaller images

any comments or feedback is welcome.

Narayan

[h0ughy]

yes i love my astrotrac as well. how long did you do on each - 90min? you must have got the polar alignment done fairly well

[seeker372011]

Hi Houghy

Usually 90 second subs and about an hour or so in total. Once the astro trac runs out of track and needs to be reset I find it impossible to reframe the target exactly, so am limited by that in terms of total exposure.


I am drift aligning

[sjastro]

Nice set of images Narayan.

Clear skies

Steven

[rolls05]

Wow, fantastic. Nuff said.

[MrB]

Yep, I love mine.
So did the previous owner (well known IIS member)
So does another IIS member that has borrowed it a few times now (and he has already reserved it for another outback adventure in July :lol: )

They are great bits of kit even with the two-hour limit before having to rewind.
The whole kit(pier+wedge+head+counterweights etc etc) is kinda expensive but well worth it in my opinion. :thumbsup:

[seeker372011]

I don't have the pier and head/counterweight but I have seen it in operation most notably at November's eclipse.

It's a nice bit of kit ..and as far as I am concerned has stopped me from sliding down the slippery slope of ever more expensive mounts and telescopes and CCDs. :)

[Ross G]

Great looking wide photos Narayan.


Ross.

[Larryp]

Good work, Narayan!

[gregbradley]

Remarkably good Narayan.

I love the whitish/golden Sagitarrius area shots. A real Canon trademark look on those areas.

Greg.

[atalas]

I can here the excitement in you voice,and I can see why....lovely set of pics Narayan.

[seeker372011]

Thanks for the comments, Ross, Laurie, Greg and Louie.

[rogerg]

Great pics! Good to see such high quality longer focal length shots from an AstroTrac. I also love mine.



How long do you spend on the drift alignment?

Regarding re-framing. I find it easy because I have a ball joint between AT and camera which has two separate adjustments for rotation vs other directions. As such I can rewind the AT then unlock the rotation of the ball joint and rotate it back the appropriate amount (30 degrees if it's the full 2 hours but I usually base it on a star's position in one far corner of the FOV). Just a tip in case you haven't tried that. It's not perfect but it's easy to get very close and there's only variation in the RA because I won't have adjusted it in other directions.

Regards,
Roger.

[naskies]

Fantastic images! I'm the previous owner of Simon's AstroTrac kit... I'd definitely like to get another one again in the future :)

[seeker372011]

Thanks Roger and Dave. It was both your wonderful images with an Astrotrac that convinced me of this mounts abilities.

Roger, drift aligning the astrotrac does take some time. Since I don't have an eyepiece in my set up and I am not using PHD to autoguide, the drift alignment consists of getting close using an altimeter and compass, then pointing at a star at the meridian as you would for normal drift alignment; taking initially 30 sec image, making an adjustment in azimuth till the star is round at 30 sec (guess a direction and see if it is getting better or worse); then going up to a minute and repeating. Usually try to get at least 3 minutes with no noticeable drift, though have gone as long as 7 minutes.

then repeating with a star on the western horizon for altitude correction-usually this doesn't need a huge change as I am back at the same dark site.

Find I sometimes need to tweak again in azimuth after getting the altitude right.

It is not as bad as it sounds but it is not a 5 minute job. And I have the astrotrac wedge

[seeker372011]

I might give this a try next time, thanks

[mbaddah]

Dam it I hate you Narayan :P They are excellent images :D Looks like drift alignment has paid off.

I think im going to have to bite the bullet and do the same with mine as I can't seem to get good alignment without it.

What are you mounting the Borg 45ED on?

[seeker372011]

Hi Mohammed

The Borg sits on a heavy duty Benro ball head, which sits on an Astrotrac wedge, which in turn sits on a heavy duty Benro tripod.

Always hang a weight off the tripods hook to lower centre of gravity and add a bit of stability

Narayan

[mbaddah]

Hi Narayan,

I also have a heavy duty Benro tripod, but use a Manfrotto 410 geared head (which i love) and 486rc2 ball head (which i hate!).

Another question, when you drift align are you running the astrotrac in test mode and following the ccd drift alignment (i.e. run it fordward 1min then backward 1 min etc..) or are you simply just imaging for 30seconds while the astrotrac is tracking normally?

Thanks again:thanx:

[seeker372011]

I tried that running one minute forward and then back but I could never really get it to work

I just start the Astrotrac tracking normally and take as I said first 30 sec then longer images and try to get rid of trailing

The only glitch I have found is sometimes I get to talking with people and forget which way I adjusted in azimuth and invariably guess wrong undoing any progress I was making .. But that's just operator stupidity not a process fault

[Ross G]

Great captures Narayan.

Ross.

[seeker372011]

Thanks Ross!