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OK, I've been tapped! Need help deciding!!

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#51 RAKing

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Posted 16 April 2009 - 06:35 AM

Dave,

If you don't know this already, you can also tailor your own safety limits in the Gemini.

One of the nice things about this control system is you can go well past the meridian when imaging. That can also be one of those "heart stopping" moments with this control system.

You will definitely hold your breath the first time you watch your scope roll well past the meridian and come *this close* to the pier. :scared:

Take care,

Ron

#52 Bowmoreman

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Posted 17 April 2009 - 08:18 AM

OK, guys... at long last a photo! :lol:

Last night was sorta frustrating. I wasn't totally thinking straight because of this nasty cold I've got... But, darn it, it was freaking clear out!

So, went out... got things all hooked up, etc... and then started to try and learn Gemini...

first, I manually aligned as close as I could on my TMB80SS to polaris (mechanically) having the scope in as close to 90 degrees as possible. I noticed that since I have an SBS setup, the helpful markings that MI put on the RA (and DEC) assembly don't line up, i.e. there isn't one for someone using native SBS. So, I had to eyeball the 90 degree "initial polar setup of RA and DEC axis.

anyways, with that part done, I then used the Alt and Az adjustments to get Polaris as centered as I could. These are much easier to use/adjust than the CGE in that there isn't any "backlash" when you tighten them down (on the CGE there's a bit of backlash/backcreep when you tighten the Alt locking bolts (Az was fine).

OK, so now to power on Gemini...

Got my location setup (Lat/Long), timezone, entered the time, etc...

Did my first Goto Bright star... The first one on the list that I knew was up, was Polaris... so selected it...

The mount slewed about 45 degees to the EAST (!) and pointed in general direction of Polaris (being under Cold Medicine at the time I gave this no thought)... So I then used the HC to get Polaris centered in the TMB... Then put in my 22T4 in the R200CF... not centered, so centered in THAT scope, then adjusted the TMB to match

Good now the scopes are parallel (again)!... At that point then aligned on Polaris...

Then tried another alignment star... no matter what I did I got the "Sorry" error... This was very frustrating...

So... at this point, I then decided to set the home position, and shut down.

Went in and READ the manual (some more)...

I discovered that I made two errors:

1) I entered my LOCAL time, not UTC time :foreheadslap:

That would explain why it was looking for brightstars that wouldn't rise for 3-5 hours, huh?

2) I wasn't using the proper procedure to get to the next alignment star... stupid user error there.

Conclusions from first (sorta) light?

1) My goodness, but this is a solid, quiet, precision mount... the slews were so... PERFECT sounding :)

2) Gemini is going to take some time, although it isn't too hard, just have to get used to it... it is QUITE logical (and comprehensive). I'm certainly going to LOVE having everything PERMANENT - I'd hate to do all this all the time (as, to be fair, I would have with my CGE - I'm LAZY)

3) I'm going to need to give some thought to cable management and mounting my anti-dew system... There's no convenient flat place to mount the Kendricks (like there was with the CGE)... Not a big deal, just needs some thought

Can't wait to get out tonight and SET THE TIME RIGHT! :lol:

As you all can see from the picture, it is so beautiful! (I like how the grey/green color(?) goes with the CF tube too!

Clear enough skies, and more reports tomorrow!

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#53 Bowmoreman

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Posted 17 April 2009 - 08:20 AM

Oh yea, one more simple question:

What is that squarish (about 3/4") electrical tab thingy that is embedded into that black anodized "joining ring" between the CW shaft and the DEC axis of the mount???

There's nothing in the manuals about it???

call me curious

clear enough skies

#54 Jason Glass

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Posted 17 April 2009 - 01:38 PM

Hi Dave,

That electrical thingy is the declination encoder connector. I engaged a blank connector to protect the pins. Just slide it straight down and off to see the pins.

Actually, I installed the arrow stickers on both axis to denote my park position. I doubt they're right on for CWD, but they're close. They are helpful if you set your park position on them, and use them as reference for a warm restart.

Thanks for the glowing feedback on AM. I appreciate it!

#55 David Pavlich

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Posted 17 April 2009 - 03:47 PM


2) I wasn't using the proper procedure to get to the next alignment star... stupid user error there.


Probably the most common Gemini mistake. Sync the first star, goto bright star, select star, center star then enter ADDITIONAL ALIGN. You can do that over and over again until you have a pointing model that is scary good.

Nice picture! It's just a great mount and you are going to be very happy with its performance.

David

#56 Bowmoreman

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Posted 17 April 2009 - 04:29 PM

Yeah - I think I was trying "next align" (or something like that)... The ex-engineer in my thought I could just brute force my way through...

of course, it was somewhat complicated by the fact that my time setting was 4 hours off, and so NONE of the "GoToBright Stars" were "available"... :lol:

My CSC says I can get out tonight, but right now it don't look so promising!
:shrug: :4 :ohmy:

clear enough skies

#57 David Pavlich

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Posted 17 April 2009 - 09:19 PM

You can go to any object in the database and do an Additional Align. It works best with the star database. Just get the ASO number, enter it and slew, center and do an Additional Align.

And once you get your pointing model all set up, make sure that when you power up, you use Warm Restart. Once you do that, goto an object and if it's off just a bit, center and Sync. I wasn't sure what would happen if you did a Sync after a Warm Restart, but it doesn't do anything to your existing pointing model.

It's a good system. You'll have a great time working through the quirkiness.

David

#58 Bowmoreman

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Posted 17 April 2009 - 09:59 PM

Well, the skies cleared up and it was a GREAT night!

I was able to get a really good model built - 5 alignment stars... had no trouble landing M51, M97, M65 and a few others (Saturn was nice tonight - our seeing actually sustained my 3-6 zoom at 3mm in the TMB w/ no issues - very crisp views...

The goto's on this puppy are very accurate, even after the first alignment star... I can't wait to next time, with the Warm Restart...

Next time out, going to try and get a really tight polar alignment, and then setting up the QHY8...

And, I hafta route a bunch of cables for the dew system as well...

Tonight was visual and Mallincam.

And then, back inside in time to watch the Sox actually pull it out (they were down 7-0 when I turned it off to do the dishes and head out to the observatory)...

Yes, a GOOD night!

clear enough skies

#59 David Pavlich

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Posted 18 April 2009 - 09:57 AM

Great news, Dave! I'm looking forward to your image from the 8. Should be terrific!

David






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