Orion's Belt mosaic - proof of concept

[MarkS]

Saturday night was full moon so why not try out an experiment as a proof of concept for a future project?

So here is the result - 8 x 5 minute subs taken with the "Banana scope" and stitched together:



Bigger version here:
http://www.markshelley.co.uk/Astronomy/2010/orionmosaicproofconceptv2.jpg

So what did I learn?  The Tak Epsilon is a fantastic scope for making mosiacs.  It is almost totally orthoscopic - there is only a tiny amount of barrel distortion.  When assembling a mosaic of full size Canon 350D images in Photoshop, the maximum distortion I had to apply to each image was 2-3 pixels to make stars overlap.

Here's hoping for clear skies this Winter

[Mac]

Looking good.

Should be a fantastic project for winter.

Although i can just make out the joins

Did you mosaic manually, or use the EQmod mosaic function?

[MarkS]

I don't EQMOD.  So I precalculated the RAs annd Decs and manually slewed to each one.

[Rocket Pooch]

do you think if we all did some data then processed it into one big image and sent it to AN or SAN we would get it published...

[Tony G]

I'll do Vega! .........................eventually. But don't wait for me.

Tony G

[RobertM]

That's pretty amazing for just 8 x 5min subs !!!

From experience you'll will find a number of issues doing this other than just the stitching issue.  For one the sky background will change, sometimes quite drastically, from night to night.  That will mean the backgrounds of each colour will differ and need to be equalised; that's on top of any gradient issues.  You'll need to ensure adequate but not excessive overlap of each frame; I found around 5-10% ideal.  That in itself will mean a fairly accurate polar alignment (to prevent rotation) and camera alignment.  Also try to avoid having bright stars near the edge of frame to reduce artifacts.

All said, I really looking forward to seeing the result, it should be stunning.

Robert

[Ian]

Does a tool exist to add diffraction spikes to an image that big?


Taxi for Ian!

[Whitters]

Roll on winter