Saturn & It's Satellites - DSLR Planetary Imaging

As clouds occupied majority of the sky (as usual😓), I was silently observing Saturn & Jupiter with naked eyes…the only things that were visible to me at that time…

Suddenly, I remembered one of my photography Friend’s question : can we image Saturn with a DSLR & Telephoto Lens. We had that discussion long back and I said that it’s highly unlikely…

Since there was nothing else to do, I decided to give it a shot… the sigma 150-600 lens together with my Camera’s 1.6x crop factor gave an effective focal length of 960mm… so why not…

And the result was something I didn’t expect…I was able to resolve Saturn’s rings and 4 of its brightest Moons : Tethys, Dione, Rhea & Titan

We learnt that it’s possible to image Saturn and it’s Satellites with a DSLR + Telephoto lens set up.

Now let’s see How…

  1. Camera Settings

The first thing we should remember is, we cannot capture both Saturn’s ring system and Moons with single exposure setting due to the difference in their magnitude.

Saturn : 0.46, Titan : 8.5, Rhea : 10.0, Dione : 10.4, Tethys : 10.2 (Lesser the magnitude value, Brighter the object)

My settings for Saturn (refer Image 1 posted below) : 1/60 sec, f/6.3, ISO800

  • This exposure is possible without a Star Tracker
  • Make sure you reframe the subject after taking few frames… otherwise, it will drift away from the field of view
    ( I used my tracker to avoid this…i.e, for convenience purpose only)

For Satellites (refer Image 2 posted below) : 1sec, f/6.3, ISO800

  • I used my tracker for this exposure. However, I think it’s possible without a tracker also… you may have to increase the ISO and reduce exposure time.

Focal length was set at 600mm for both.

A word of Caution : these were the settings for my observing conditions ( it was quite Hazy & Cloudy that day)

  • If the seeing conditions are better, you may have to lower the Exposure time and/or ISO to get a proper exposure
  1. Pre Processing
  • This image is straight out of camera. Can you recognise the planet?May be not!

  • My camera records images as 6000 x 4000 pixels. However, Saturn occupies a very small portion in the entire image.
  • when cropped down to 900x600 pixels, the Gas Giant becomes visible.
  • also, this cropping is necessary for the next step - Stacking

(Software used for cropping : PIPP)

  1. Stacking
  • Stacking is used to increase the signal to Noise ratio of the Image : More images, Better image quality
  • Here I have stacked 2 sets of exposures separately

(Software used for Stacking : AutoStakkert)

  1. Editing
  • Edited in Lightrooom Mobile to improve contrast and sharpness
  1. Combining the 2 exposures :
  • used Double Exposure tool in Snapseed to get the final composite image
  • My first choice was stacking the Saturn images & satellite images together in AutoStakkert. The result was not satisfactory, so decided to go with Snapseed.

It’s difficult to cover the entire process in this post. I have tried to do my best. If you guys need any info or have an advice to improve the imaging, please do share here… :slight_smile:

#photonsfromthepast #astronomyforeveryone

Canon 80D | Sigma Contemporary 150-600 | Sky-Watcher Star Adventurer

Chennai, 15.10.2020