Astrotrac Results - First Two Weeks With Tracking

[iksose7]

Evening SGL, i recently purchased an Astrotrac TT320X-AG and thought i would give you my thoughts and share my results so far. Any critism and tips or tricks that may help me improve are very welcome.

My Astrotrac arrived probably about a month ago now so i have had roughly 2 weeks of Moonless sky to image. This is also my first tracking platform after doing fixed tripod for about a year so its been a great fortnight, as i feel i have squeezed just about all i can out of 30 second exposures! Dont get me wrong, fixed tripod AP is great but i've had an itch to go deeper for quite a while now.

The images shown are in the order they were taken. I will put the exposure details below each image. All images are taken with a Canon 1100D (un-modded) and either a Canon EF 50mm 1.8 or a Canon EF 70-300mm 5.6 IS USM.

Since my AT arrived just as the Moon was new, i had two weeks to sit and stare at my new piece of gear. I set it up every now and then to get familiar with it. This is a strong point for the AT, i takes 5 minutes to set up and take down. I took advice and also replaced the grub screws in the polar scope with thumb screws to make collimation much easier.

A couple of weeks later, my first image, like 90% of everyone here was of course M42. This was a one hour exposure. I was quite happy with my first neb but the image made one thing obvious - the 70-300mm was ****. As you can see, it produces odd star shapes and is just overall, not well suited for AP. Unfortunately i dont have the money or access to anything better right now so this lens will have to do for now.

Exposure Details - 2 minute subs, ISO 800, f5.6, calibration frames (darks, bias) also took some 10 second subs for the core.

I have also added an hour to M42 but prefer this version for some reason... i think the core looks alot better.

My second night imaging i managed to shoot two targets. The first, M45 the Pleiades Star Cluster - one of my favourites. This night taught me that my Polar Scope needed re-collimated more accurately as i couldnt manage 4 minute subs without trailing. I re-collimated the next day.

Exposure - 19 3 minute exposures, ISO 800, f5.6, calibration frames (darks, bias)

I also got 48mins on Andromeda using the nifty fifty. This lens is awesome, nice round stars. Obviously this image is very heavily cropped.

Exposure - 12 4 minute exposures, f5, ISO 800, calibration frames (darks)

The next clear night i shot an hour on M33 at 300mm and an hour on Orion at 50mm. All that data was useless. The focus on m33 had slipped and light pollution had creeped in on Orion as it approached the horizon. Gutted. I also had to re-collimate after dropping the Polar Scope on the ground i still need to buy a washer to stop this happening again.

A couple days later i set my gear up with a newly bought plug socket power source, so i dont have to buy batteries anymore unless i am shooting in a remote location. I left my camera with the 50mm pointing at Orion. I came back an hour later to find all frames except the 1st covered in a thin layer of cloud... oh well, i had a flick through and found a nice looking shot. The cloud acted as a natural diffusion filter

This was a single 3 minute exposure at f4.5 and ISO 1600.

Next up was the Horsehead or Barnard 33 if you want to get fancy. This was taken two nights ago under the new Moon after failing again to find PANSTARRS. I framed the whole of Orions Belt just to switch it up a bit from most Horsehead images.

Exposure Details - 1 Hour 39 Minutes of 3 minute exposures, f5.6, ISO 800, calibration frames (daks, bias, flats)

And finally, my image from last night. Caldwell 49, the Rosette Nebula. Didnt take me long to find it, took me blumming ages to frame it. I was very surprised when this image popped out of DSS. Since i dont have a modded camera, i as not expecting so much to be picked up.

Exposure Details - 1 hour 42 minutes of 3 min subs, f5.6, ISO 1600, calibration frames (darks, bias, flats)

Overall i think the Astrotrac is an excellent piece of equipment. Yes it is very expensive, including tripod and tripod heads my bill is over £1000. The polar scope lets it down the most but you get used to its flaws and can correct them. I also think portability and ease of use makes up for that. I've had to make some adjustments to my polar scope arm aswell as the polar scope but if you can get it in a sweet spot, you can get some long subs. I can now manage 4 minutes but if i put some more time into fine tuning i could manage longer. I recommend anyone who owns an AT or is thinking of buying one, joins the Astrotrac Yahoo group. There you can find the solution to any problem you may encounter.

Next thing i will be doing is selling my 70-300mm and putting the money towards a EF200L, which appears to be an excellent lens for AP.

Thanks for taking a look, and remember any tips are welcome.

Oh, and sorry about the images being so big. I'm not sure how to make them smaller.

[stan26]

Hi Iksose, Very nice results there well done!, And very encouraging for the likes of me who has just brought an astrotrac and waiting for delivery, albeit a 2nd hand older model off astrobuysell, I can't wait to get it and try it out!

I got mine for £450 delivered complete with Giottos tripod, manfrotto ball head, manfrotto 410 geared head, tripod bag, and polar scope!

I recommend the canon 200 L 2.8 prime, its a fantastic lens in every way, I have one and will never part with it!

James.

[iksose7]

Thanks Stan whoah! Sounds like you got yourself a bargin! Never heard of Astrobuysell, on my way now to check it out.

[sologuitarist61]

Excellent set of images - that Astrotrac is certainly worth the money

[Gina]

Wonderful images

[StuartJPP]

A good selection of images there. Regarding the 70-300mm, you could try stopping it down a little by reducing the aperture. Would be preferable to do with an aperture mask on the front of the lens rather than using the aperture blades to prevent diffraction spikes. This will increase exposure time though.

Like this:

http://stargazerslou...s/#entry1743995

[iksose7]

Thanks Richard and Gina

[iksose7]

Cheers Stuart. Never even thought about stopping the lens down, i guess i thought f5.6 was high enough as it was. Will be sure to give that a go next chance i get.

[Adamar98]

Fantastic images! I have more or less this exact setup. Same lenses too! It's very encouraging to see what can be achieved with it! Only downfall with the Astrotrac is the polar scope. The magnetic fastener is pants. I've stopped counting the amount of times it's fallen out and hit me in the eye! I'm was also looking at the ef200l but I'm starting to sway towards the ts65q. I look forward to seeing more images from you.

[laser_jock99]

Promising set of images there- I love the portability of these mounts.

[x6gas]

Very nice images - well done!

I have an astrotrac that I take on holiday... I find the polar alignment to be a bit of a pain, but once done it's a nice bit of kit (haven't got anything as good as you, though!)

[iksose7]

Fantastic images! I have more or less this exact setup. Same lenses too! It's very encouraging to see what can be achieved with it! Only downfall with the Astrotrac is the polar scope. The magnetic fastener is pants. I've stopped counting the amount of times it's fallen out and hit me in the eye! I'm was also looking at the ef200l but I'm starting to sway towards the ts65q. I look forward to seeing more images from you.

Thanks Adamar. Yes the polar scope is a pain, but i've read you can place a slip joint washer on it to stop it slipping. I always knock it out when adjusting the ball head for framing!

Ooooh, an astrograph? I have my eye on one from Altair. Hopefully should be able to afford it by the end of the year if all goes according to plan!

[x6gas]

Yep Polar Scope is a pain, especially given how expensive it is, but like others I slip an o-ring over it to stop it falling out...

[iksose7]

Promising set of images there- I love the portability of these mounts.

Thank you!

Very nice images - well done!

I have an astrotrac that I take on holiday... I find the polar alignment to be a bit of a pain, but once done it's a nice bit of kit (haven't got anything as good as you, though!)

Cheers x6gas! Yes, a bit of a pain is right. Especially finding that 3rd star. I hope to take mine South at some point this year and get some shots of Southen skies. Something i would not be able to do with a big ol' mount and scope, not to mention the rest!

[iksose7]

Recently expanded my processing knowledge and had a go at reprocessing M42 and M45. Though i would just post them here and save starting another thread.

M42

M45

And heres one from the other night. M81+82 not to long before the sun started rising. Only about 30 minutes worth. Was just testing out my new EF200L. Hopefully i will be giving it a proper test in a few hours

[Gina]

They're very nice

[Coco]

Excellent and great write up

[iksose7]

Thanks guys!

[Welrod50]

A great input with great images. Well worth the read, nice one

[iksose7]

Cheers Scott

Heres a couple more with the new lens from the other night

Comet Panstarrs: 12 minutes

The Iris Nebula Widefield: 48 minutes

[Gonzo]

Very nice pictures.

This astrotrac is on my list of must have..

What do you use for tracking please?

oh and from part of Southern France are you taking those pictures please?

[Gina]

Very nice

[iksose7]

Thanks Gina and Gonzo! Unfortunately i deleted a few images from my gallery before to make room, not realising they would also be deleted from this thread. Any ideas how i can get them back in place?

Very nice pictures.

This astrotrac is on my list of must have..

What do you use for tracking please?

oh and from part of Southern France are you taking those pictures please?

Yes the AT is a great bit of kit, very easy to use aswel which is great. Got it set up outside now waiting for dark

I use the Astrotrac TT320x-AG for tracking, if you ment what i use for guiding then the anwser would be nothing. Although the AT does have an auto guider port. I am in the Dordogne region, a great dark site.

[Gonzo]

I do know (kind off) the Dordogne, I'm from Pau, not that far away

I envy your dark nights

[iksose7]

Hi Gonzo. Yes, i believe i have heard of Pau. I love the clear dark nights, dont think i could live in the UK again!

Heres an image from Sunday night of M101 - The Pinwheel Galaxy. Think i will just keep updating this thread with Astrotrac images so people thinking about buying one can see what kind of results can be had. I know thats exactly what i was looking for when i was thinking about making the investment!

Exposure Details:

56 180 second subs, f3.2, ISO 1600, calibration frames, 200mm