Tuesday, June 10, 2014

Planetary Imaging

A couple of years ago I bought a Lumenera Lu135 industrial camera and retrofitted it for planetary imaging. All that really involved was putting a 1.25" barrel on it that I bought from Xagyl Instruments (I love supporting Canadian companies!).  Its an amazing camera! For just under $300 I acquired a camera that would have cost me over $2000 if it was specialized for Astronomy.  In fact, you can compare the Lumenera Skynx 2.0 and the Lu135m cameras.  They are virtually identical except the Skynx is marketing for Astroimaging while the Lu135 isn't.  (It also helps that I got my camera used on ebay).

Since its a monochrome camera taking colour photos was a bit of a challenge.  It involved taking on series of photos with a Luminence filter (essentially just a UV/IR filter) and then one each in Red, Blue and Green; hence the name LRGB.  It was a bit frustrating to remove the camera, unscrew a filter, screw in the new one, replace the camera, correct the orientation and then refocus it.  Then about a month ago I bought a manual filter wheel and a cheap set of LRGB filters from Meade.  Right now Meade is selling the LRGB set for under $30.00. Its a steal if you're looking to get into LRGB imaging.  They aren't quite the same quality as something from Astrodon or Lumicon but at 1/10 the price I'm not going to argue.

Anyway, a few months ago I took some decent pictures of Jupiter and then just last week I started pointing my telescope towards Saturn. The 4 images below are the Luminence, Red, Green and Blue images I took.  They aren't in colour, just taken through colour filters.  Then using a program like Photoshop or Nebulosity each image is mapped into a colour channel.  The three colour channels (RGB) are combine with the Luminence image to create a composite colour image.





The composite colour image is below.  I think my exposure time was too long so the images are slightly overexposed.  Its also unfortunate that Saturn is very low in the Southern horizon right now.  Double bad is that because its the middle of summer it doesn't get dark out until around midnight.  This means there are few, if any, really good opporunities to image Saturn.  And even then Saturn is only about 25 degrees above the horizon.  Jupiter on the other hand was well above 60 degrees.  That made for less light pollution and less atmosphere to shoot through.  Ditto for Mars.

Saturn LRGB

I've also included a shot I took of Jupiter and one of Mars.

Jupiter shows a lot more detail because it much bigger than Mars.  In fact even through a small telescope or binoculars its possible to see the four moons Galileo first looked at more than 400 years ago.  Despite the smaller size, the image of Mars is really quite interesting.  You can clearly see the Northern and Southern Ice caps along with some darker highlands and lighter plains.  The white ice caps are actually made not of water but mostly frozen Carbon Dioxide!

1 comment:

  1. The image of Jupiter is fantastic! The level of detail on the bands is pretty amazing