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Shadowalker
Apocaloptimist


Reged: 11/23/04
Posts: 10857
Loc: Carriere, Mississippi, USA
First Starlight Sigma DC 18-200mm zoom
      #854008 - 03/04/06 10:55 PM Attachment (32 downloads)

First starlight, Sigma DC 18-200mm zoom.

I put the Canon as the sole passenger on my LXD75 mount. This was really a test shot for Pojmanski tomorrow morning and to see how this lens does.

There was a fierce gradient from the LP from Picayune. It's really getting bad. Had to try all sorts of things to fix it.

10x60, ISO800
Lens set wide open (F3.5) and FL=18mm
dark applied, no flat

I'm running an Alnitak now with the lens at FL=200, Exp =180s

Attachment

--------------------
"The truth rarely gets in the way of a good story. ~ R. Woods


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JakeJ
Carpal Tunnel


Reged: 08/31/04
Posts: 1556
Re: First Starlight Sigma DC 18-200mm zoom new [Re: Shadowalker]
      #854014 - 03/04/06 11:02 PM

Tom -

It looks pretty well-behaved at the corners, especially for a zoom lens! Hard to say about the CA, though, as your image appears to be a bit clipped.

--------------------
12.5" Discovery TD
Vixen ED103S

...and way too many eypieces to list!


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JakeJ
Carpal Tunnel


Reged: 08/31/04
Posts: 1556
Re: First Starlight Sigma DC 18-200mm zoom new [Re: JakeJ]
      #854015 - 03/04/06 11:02 PM

BTW - are you getting a new mount, or sticking with the LXD-75?

-Jake

--------------------
12.5" Discovery TD
Vixen ED103S

...and way too many eypieces to list!


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Shadowalker
Apocaloptimist


Reged: 11/23/04
Posts: 10857
Loc: Carriere, Mississippi, USA
Re: First Starlight Sigma DC 18-200mm zoom new [Re: JakeJ]
      #854037 - 03/04/06 11:15 PM Attachment (28 downloads)

yes, it's clipped. I'll re-do it and leave the gradient so you can evaluate for CA.

ARGGGHHHHH cry of anguish...

My G11 arrived yesterday. With a dead electronic board. Seller will make it good, but we need to wait till monday to make the arrangements. I'm paying for overnight.

First impression - this mount is rock solid. Different class from my GP and GP clones.

I'm keeping this LXD75 for things like this. seems well suited for it.

Here's my new ride...

Attachment

--------------------
"The truth rarely gets in the way of a good story. ~ R. Woods


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fellers
Pooh-Bah


Reged: 12/29/05
Posts: 1094
Loc: NY by ADK park
Re: First Starlight Sigma DC 18-200mm zoom new [Re: Shadowalker]
      #854075 - 03/04/06 11:53 PM

I am looking forward to seeing your comet photo. Hopefully it all comes together for you Tom.

--------------------
MVAS Observatory

Old Forge

The farmer allows walkers to cross the field for free, but be aware that the bull charges.
"SUA SPONTE"


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comets4tom
professor emeritus


Reged: 02/08/05
Posts: 638
Loc: Texas
Re: First Starlight Sigma DC 18-200mm zoom new [Re: Shadowalker]
      #854165 - 03/05/06 01:00 AM

That battery has a familiar look to it. It sure does the job doesn't it ?

Tom Hopkins

--------------------
Vixen R200SS,Meade 2045D, Orion Explorer 90mm, Orion Starblast Imaging Reflector, Vixen Great Polaris DX with iOptron Goto Nova, Meade LX200GPS 8 Inch, AT72ED
Canon 1000D,Orion Starshoot II Monochrome, Atik 16IC


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JakeJ
Carpal Tunnel


Reged: 08/31/04
Posts: 1556
Re: First Starlight Sigma DC 18-200mm zoom new [Re: comets4tom]
      #854255 - 03/05/06 02:48 AM Attachment (24 downloads)

Looks very similar to my old setup!

Hope you get it running again...

Attachment

--------------------
12.5" Discovery TD
Vixen ED103S

...and way too many eypieces to list!


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Shadowalker
Apocaloptimist


Reged: 11/23/04
Posts: 10857
Loc: Carriere, Mississippi, USA
Re: First Starlight Sigma DC 18-200mm zoom new [Re: Shadowalker]
      #854354 - 03/05/06 06:49 AM Attachment (26 downloads)

Here's the full frame, minimally processed - you can see the gradient I was battling.

Attachment

--------------------
"The truth rarely gets in the way of a good story. ~ R. Woods


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Shadowalker
Apocaloptimist


Reged: 11/23/04
Posts: 10857
Loc: Carriere, Mississippi, USA
Re: First Starlight Sigma DC 18-200mm zoom new [Re: JakeJ]
      #854355 - 03/05/06 06:51 AM

Quote:

Looks very similar to my old setup!

Hope you get it running again...




What can I say? Great minds think alike? lol

Oh, I'll get it running if I have to put LXD55 motors on it. In fact, I might anyway.

--------------------
"The truth rarely gets in the way of a good story. ~ R. Woods


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Fordracer1
scholastic sledgehammer


Reged: 12/05/04
Posts: 949
Loc: Springfield, MO
Re: First Starlight Sigma DC 18-200mm zoom new [Re: Shadowalker]
      #854604 - 03/05/06 11:33 AM

Tom,

Once you get things worked out you'll love the mount! I really like mine. It made a world of difference in my photography. Looks like yours is a non-Gemini like mine. Something I really like about my G-11 is the DSC setup. I can push the scope a lot faster than a GOTO could slew it. I just shove it to the general area of my target, then look at the DSC display to get it right on. It seems the DSC is more accurate than my Autostar set up was. Congrats on the mount!

--------------------
John Moody
Losmandy G-11
Orion 8" Newt w/Moonlite CR1 motofocus
Baader MPCC
NS11 GPS Starbright Carbon Fiber
Orion 120ST
Meade 5000 80/480 Triplet APO
WO .8 Reducer
15X70 & 25X100 SkyMasters
Modded Canon 40D
Stiletto IV Pro
WO Binoviewer
http://panthercreekastro.mysite.com


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Fordracer1
scholastic sledgehammer


Reged: 12/05/04
Posts: 949
Loc: Springfield, MO
Re: First Starlight Sigma DC 18-200mm zoom new [Re: Fordracer1]
      #854626 - 03/05/06 11:44 AM

Tom,

I meant to mention that the most common mistake I make since getting the G-11 is setting the slew speed to 16X for moving the scope around when getting my framing right and forgetting to set it back to guide speed before starting the exposure. GuideDog really goes nuts when it thinks it is guiding at 2X but the controller is set to 16X!! It makes some really interesting looking trails

--------------------
John Moody
Losmandy G-11
Orion 8" Newt w/Moonlite CR1 motofocus
Baader MPCC
NS11 GPS Starbright Carbon Fiber
Orion 120ST
Meade 5000 80/480 Triplet APO
WO .8 Reducer
15X70 & 25X100 SkyMasters
Modded Canon 40D
Stiletto IV Pro
WO Binoviewer
http://panthercreekastro.mysite.com


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c131frdave
Post Laureate


Reged: 01/17/05
Posts: 4376
Re: First Starlight Sigma DC 18-200mm zoom new [Re: Fordracer1]
      #854628 - 03/05/06 11:46 AM

Looks great Tom. I love the mass of aluminum and glass on one side, and the lone little weight on the other.

I didn't realize you had the Skywatcher version. Is it the same as the Orion, or a little different?

Nice looking setup.

--------------------
Tak NJP

Various sizes and shapes of formed glass


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