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So I get a VERY clear night, and a SURPRISE!!

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#1 SanDiegoPaul

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Posted 11 February 2010 - 12:25 AM

Clear Sky Clock and WeatherUnderground both told me to stay inside tonight. But at sunset I could see no clouds, and the local air was so clear the distant mountains looked like they were in my back yard.

I set up the CGEM and my APO-90, then did my alignment. I'm getting better and better at learning the menu (remember I'm a Meade SCT kinda guy) and getting the alignment done. I then did a Polar Align and decided to see how long I could get exposures before I got star trails.

I started with a 5 minute test. I took six shots of Hind's Variable nebula with no guiding. I was stunned. No drift, no trailing stars and no guiding!

Next I tried a SAC cluster and went for 10 minutes. Three images, and two of them were usable!!!!!! I could NEVER do that on my Meade SCT. never would it happen.

I'll post the pics as replies to this message, when I get them off that computer. Right now, it's imaging the Double Cluster ... :jump:

#2 j.w.white

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Posted 11 February 2010 - 01:12 AM

Paul - sounds sweet!! I'm still waiting for the skies to clear (looks like another week of armchair astrophotography), but I'll be content to live through your picts. I've got a whole list of things I wanted to do once it clears (more practice with PEMPro, working more with SkyX and TPoint, various lens tests - but once I see clear sky again I'll probably crack and just go for the imaging to remind myself of why I like doing this!

#3 SanDiegoPaul

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Posted 11 February 2010 - 01:28 AM

Hey, John thanks. I am doing another PemPro run on it right now. Like you, I need to get used to this piece of software. Not just for this CGEM but also for my Lx200-R which most certainly will make better use of PEC correction. Better than I can with teh Meade Software at least.

#4 SanDiegoPaul

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Posted 11 February 2010 - 02:42 AM

Paul - sounds sweet!! I'm still waiting for the skies to clear (looks like another week of armchair astrophotography), but I'll be content to live through your picts. I've got a whole list of things I wanted to do once it clears (more practice with PEMPro, working more with SkyX and TPoint, various lens tests - but once I see clear sky again I'll probably crack and just go for the imaging to remind myself of why I like doing this!


PemPRO got me under 3 ArcSec/Px tonight! I took a reading consisting of three cycles of PE, and analyzed them. Uploaded the corrected curve, and remeasured - with PEC on this time. Here is the result: :jump:

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#5 SanDiegoPaul

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Posted 11 February 2010 - 03:54 AM

I'll post the pics as replies to this message, when I get them off that computer.


Here is almost raw data from 30min. of 5-minute subs. They were reduced in CCDsoft and stacked but that's all. 5 minute unguided shots of Hind's Nebula with this mount BEFORE the PemPRO correction to PE.

Nice!!! I am impressed wtih the CGEM very much. Obviously 5 min subs were not enough, for an image of this particular object taken in the city. But the point of this picture is to show how round the stars stayed, after 5 minutes of unguided exposure. Times six!

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#6 saadabbasi

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Posted 11 February 2010 - 06:10 AM

Maybe its just me, but the stars look slightly elongated to me.

#7 RTLR 12

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Posted 11 February 2010 - 06:50 AM

Hey Paul,

It looks like you're starting to feel a little more comfortable with the CGEM and finding your way around the software. The pic is great for 5min. unguided. Just imagine how great they will be with closer alignments, PEC, and guiding. Congratulations! I had a pretty good nights viewing here too.

Stan

#8 EricJD

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Posted 11 February 2010 - 07:43 AM

Grats man, nothing like having a mount that works the way you want it to right off the bat.

#9 Starhawk

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Posted 11 February 2010 - 09:06 AM

Progress always feels good.

I am hoping the wake of that same storm system leaves AZ with some clear viewing time this weekend.

-Rich

#10 LLEEGE

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Posted 11 February 2010 - 09:10 AM

Maybe its just me, but the stars look slightly elongated to me.

Me too.

#11 CounterWeight

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Posted 11 February 2010 - 10:40 AM

Maybe the stars look round compared to what you were getting before, but these aren't round in the image you posted. Nothing some guiding wouldn't help, is there a reason to go unguided with your setup?

#12 Gord

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Posted 11 February 2010 - 10:56 AM

I don't think they are round either...

But, isn't this still a very good result considering everything (stock out-of-box CGEM, no drift align, no guiding, no PEC, and a 5min exposure)? How much better would a Tak EM200 do in this same test?

Seems to me like the CGEM quality is pretty decent given the price point and the above results would be a good starting point to work from (guiding, etc.).

Clear skies,

#13 SanDiegoPaul

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Posted 11 February 2010 - 11:25 AM

Maybe its just me, but the stars look slightly elongated to me.


Of course! As I said, the purpose was to just prove how good it was on an unguided 5 minute shot. Those images are not worth trying to make something out of :foreheadslap:

#14 RTLR 12

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Posted 11 February 2010 - 11:29 AM

Gord and Eric got it...Did you other guys read the OP where Paul says this is a TEST? It's not about the stars being perfect, it's about 5min subs, unguided, and Paul's success in getting such great result's for the first time.

Stan

#15 neptun2

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Posted 11 February 2010 - 11:44 AM

Yes for 5 minutes unguided it is definitely good result. Much better than my heq5 pro. When you include autoguide this will be very good imaging system.

#16 saadabbasi

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Posted 11 February 2010 - 11:44 AM

Paul, I didn't really mean to say anything bad about your image. If anything, it says that now your mount is ready to guide.

I just wouldn't call them round, thats all. I didn't mean anything by it.

Sorry if I caused any offense.

#17 chicot

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Posted 11 February 2010 - 11:50 AM

That's a great result. Be interesting to see what you can get your LX200 down to.

#18 DaemonGPF

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Posted 11 February 2010 - 12:44 PM

I think this is quite good at 5 minutes with rough alignment Paul. I know my CG5 would have never pulled that off at 5 minutes unguided.

#19 DaemonGPF

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Posted 11 February 2010 - 12:46 PM

I don't think they are round either...

But, isn't this still a very good result considering everything (stock out-of-box CGEM, no drift align, no guiding, no PEC, and a 5min exposure)? How much better would a Tak EM200 do in this same test?

Seems to me like the CGEM quality is pretty decent given the price point and the above results would be a good starting point to work from (guiding, etc.).

Clear skies,



IIRC a Tak EM200 is at +/- 5" PE and has no PEC ability right? For Paul to pull of +/- 3" on a mount that costs 1/3 as much, I think it's definitely impressive.

#20 chicot

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Posted 11 February 2010 - 12:57 PM

It's better than that - it's under 3 arcsec peak-to-peak.

#21 Tim C

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Posted 11 February 2010 - 04:39 PM

This shot looks very comparable to what i got with my em200 unguided when i tried it after receiving the mount. My em200 has 7 seconds peak to peak. Looks like you have a great sample... Dont ever sell it! Wish i had gotten a sample that good, might have saved me about $4500. I'm interested to see how well it guides with the pec engaged.

#22 DaemonGPF

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Posted 11 February 2010 - 05:10 PM

I agree. Paul, you're just going to have to fire up this thread again when you get your guiding going.
:grin:

#23 DaemonGPF

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Posted 11 February 2010 - 05:28 PM

It's better than that - it's under 3 arcsec peak-to-peak.


http://astronomics.c...oduct_id/EM200U

Every vendor I can find quotes +/- 5". Here's some charts I've found from actual owners:

+/- 4"
http://www.astrosurf...r/equipment.htm

+/- 5"

http://www.kolumbus....equipments.html

< 1"

http://picasaweb.goo...086898249580626

+/- 5"

http://www.astrosurf...e/em_200_pe.jpg

+/- 10 and +/- 20

http://lambermont.dy...g/astro/pe.html



I don't know, it seems it varies quite a bit mount to mount.

#24 chicot

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Posted 11 February 2010 - 05:44 PM

Crossed wires. I meant that Paul is getting better than +3/-3 as his is less than 3 peak-to-peak.

#25 DaemonGPF

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Posted 11 February 2010 - 06:42 PM

Ah. Gotcha.






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