7 replies to this topic

[EdDixon]

First real test of the SkyGuider Pro with a Nikon D5600 and 70-300mm zoom lens.  A rocket club member printed a 3D device to get an initial polar alignment using PS Align Pro app for iOS.  Then used a right angle finder to set Polaris at the right position.  This is the initial setup with that attachment and an iPhone 12.

 

https://www.dropbox....ew=IMG_0012.png

 

https://www.dropbox....w=IMG_0051a.png

 

 

This image is taken about 8PM at 260mm zoom, f6.3, ISO 100, and 73 seconds.  Camera mounted via ball head direct to front of SGP.

 

 

https://www.dropbox....=DSC_0577b1.png

 

 

Doing a second alignment, using the SGP bracket and counter weight might have been better.  That would figure the camera and all weight into the mix.  That’s a test for another night.

 

Because of a family member injury, I’m at home at night now for a few months.  With a street light 75 feet to the left, a porch light 20 feet straight ahead and building lights 75 feet to the right, it’s pretty well light polluted.  I looked for any object I could see in the sky and tried to point to that.  Was pretty much total guesswork.  It wasn't until afterwards, and I compared the images with Stellarium, that I figured out what I had an image of...

 

[D_talley]

Cant see your photos using your links.

[AdrianoMS]

The links don't take us to your photos, but to a sign-in page.

[EdDixon]

The links don't take us to your photos, but to a sign-in page.

I dont use Dropbox often.  Let me see what I can do.

[EdDixon]

See if these work:

 

https://www.dropbox....0577b1.png?dl=0

 

 

https://www.dropbox....G_0012.png?dl=0

 

 

https://www.dropbox...._0051a.png?dl=0

[D_talley]

Got them. Links are working now. Thanks

[lakeorion]

Is the picture of Rigel intentionally black and white?  It looks monochrome and very binary.  Possibly stretched to the point of all stars are saturated?  Or overexposed?

 

The good news is the stars aren't apparently leaving trails, the bad news is, your zoom appears to have chromatic aberration.  Brighter stars in the corners are leaving comet trails.  Try a 35mm to 85mm prime lens, stop it down 1-2 stops from wide open and that goes away.

 

Focus, polar alignment, and tracking look pretty good, you're most of the way there.

[EdDixon]

Is the picture of Rigel intentionally black and white?  It looks monochrome and very binary.  Possibly stretched to the point of all stars are saturated?  Or overexposed?

 

The good news is the stars aren't apparently leaving trails, the bad news is, your zoom appears to have chromatic aberration.  Brighter stars in the corners are leaving comet trails.  Try a 35mm to 85mm prime lens, stop it down 1-2 stops from wide open and that goes away.

 

Focus, polar alignment, and tracking look pretty good, you're most of the way there.

 

Yes, the shot was forced as B/W.  My only real reason for the test was for accuracy of polar alignment and lack of star trails for longer exposures with higher mag settings. 

 

The lens I will normally use for this mount is either a 10mm f2.8 or a 35mm f1.8.  The lens for this shot was a mid range Nikon 70-300 zoom I usually only use for nature shots.  This taken last Jan on a South Africian photo shoot.

 

https://www.dropbox....G_0234.png?dl=0

 

I do plan a few more shots on a different night using the 10 and 35 lens.  My plan is to use them for meteor showers where a series of time lapse shots are done over some hours.

 

Later this year I do hope to get a William Optics GT71 scope for wide angle shots with higher mag.  That will be mounted on an AVX mount with guide scope and ASI cooled camera.

Edited by EdDixon, 24 February 2021 - 08:21 AM.