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CGEM results while guiding

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#1 tboss70

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Posted 11 March 2012 - 10:27 AM

For the CGEM owners who are using their mounts for guided, or unguided, astrophotography, what have been your results?

I'm curious if you have success at 500mm? 1500mm? How long have the subs been?

Thanks for the info!

#2 Mapleton

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Posted 11 March 2012 - 02:57 PM

Unguided with a Televue 76, I've gotten pin point stars up to 4:30 seconds. With the 102, I've gotten 3 minutes. Hypertuned I truly believe I could do better because my mount is not the smoothest (came that way new).

#3 SureshotPL

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Posted 11 March 2012 - 07:58 PM

I routinely take 20 and 30 minute guided subs with my ED80.I can post a 100% crop of a sub if you'd like.

#4 tboss70

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Posted 11 March 2012 - 09:43 PM

Thanks for the comments. I would love to see the sub.

#5 SureshotPL

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Posted 11 March 2012 - 10:26 PM

This is from a 30min Ha sub i took a few weeks ago:

Posted Image

#6 tboss70

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Posted 12 March 2012 - 07:10 AM

Nice, thanks Kyle.

#7 Orion58

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Posted 12 March 2012 - 08:14 AM

My (autoguided) imaging has been done at 1280mm (f/6.4). If my rig is balanced/aligned properly and the wind is calm, I can take 4 min subs with few problems. I have not attempted longer subs. Wind is the biggest issue for me...if it is calm, things just seem to go SO much better... :grin:

#8 sparky123

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Posted 10 June 2013 - 03:18 PM

im using a "stock" cgem and run guided 10 minutes subs with no problem.

#9 orion69

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Posted 10 June 2013 - 03:24 PM

Almost all my images are 30 min subs @ 765mm or 900mm (Equinox 120, now sold), to this day never dropped a single sub because of mount error.

Sorry, just saw this is old thread...


#10 Raginar

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Posted 10 June 2013 - 08:20 PM

I was able to do 8 and 10 minute exposures with my CGEM at 1600, 1200, 800 and 650mm.

The key to it was keeping the weight down to a manageable level (around 20# for my particular one).

It improved significantly after hypertuning it.

#11 dksolar3294

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Posted 11 June 2013 - 01:16 PM

I've got a 3yr old CGEM & routinely see a lot of "eggs". Besides the main mount, guide quality is also dependent on guider hardware (scope, mount, camera) & software. For you guys getting nice round stars at 10+ min, what guide equipment / software are you using ?

#12 orion69

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Posted 11 June 2013 - 02:42 PM

I've got a 3yr old CGEM & routinely see a lot of "eggs". Besides the main mount, guide quality is also dependent on guider hardware (scope, mount, camera) & software. For you guys getting nice round stars at 10+ min, what guide equipment / software are you using ?


Hardware is in my signature, software is PHD.

#13 gmartin02

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Posted 11 June 2013 - 05:33 PM

Hi Knez,

I noticed you are using a SX Lodestar + TSOAG9 combo for guiding. I am currently using a guide scope, but I am thinking of getting this combo myself for guiding with my AT8RC. I also have shorter length scopes I use for AP (Tak FS-60CB & Orion 110 ED).

Is there any reason not to also use an OAG for the shorter focal length telescopes?

Greg

#14 orion69

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Posted 11 June 2013 - 08:20 PM

OAG is always recommended (at least I'm recommending it to everyone, but everyone is not listening :)) no matter which FL.
It's the best way of guiding.

#15 Whaleboy

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Posted 12 June 2013 - 01:47 AM

Before the local sky went bad on me a few months ago (clouds roll in every night, or *BLEEP* seeing), I was doing Narrow Band at 952mm and 760mm (5" refractor and 6" Mak-Newt), OAG, with 20 to 30 min exposures, and didn't lose a single sub. I did hypertune though (with the kit). My first attempts at imaging were mixed (although all in all I was pretty happy). Once I went to CCD with OAG, and hypertuned, any minor issues went away. Although to be fair, I got the ccd OAG setup and hypertuned at the same time (if memory serves), so it may have performed just as well without the hypertune, although I can tell it smoothed things out for sure.

I've since upgraded to an AP Mach1, which I've barely had a chance to image with due to the previously mentioned weather. As soon as I have a little free time, I need to sell the CGEM, but for the time I used it, it worked great.

-David

#16 PhilCo126

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Posted 13 June 2013 - 06:54 AM

10 minutes should be no problem with a good CGEM :p

#17 Raginar

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Posted 13 June 2013 - 01:29 PM

Honestly getting a good guider (lodestar) and switching to a finder-guider really helped. Other things to look for is how much weight you have on the scope (lower is better) and if you're using a finder guider, attach it to the scope it's guiding... for some reason that reduced differential flexure for me.






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