Astrophotography trip report – Lake Brown September 2016

I went for a trip to Lake Brown again – north of Merredin in Western Australia.  I assumed that there would be water in the lake.  After carefully considering weather conditions across multiple locations – I assessed that the wind speed here would drop to still conditions.  I was concerned that there was a large amount of cloud originally forecast – while this was scheduled to clear, it’s always a bit unpredictable.  Checking the forecast conditions – I monitored several weather sites and two different cloud prediction sites.

The driving trip there was actually a bit of a mess.  I was being a lazy and used a new gps system rather than using familiar routes.  It led me on a merry drive through ungraded (gravel) roads across the country side.  This meant that rather than driving at 110kmph – I was much more severely restricted – frequently 40-60kmph.  Note to self – common sense > technology.

I managed to get to location around sunset – I feel that it’s important to get to the location while it is still light to scout properly.  I wasn’t disappointed – about 100m walking into the lake – I found some very shallow areas – pressure ridges in the salt lake bed were showing through the shallow water.  Pressure ridges are usually evident where the water level is dropping and the dry salt lake bed contracts, causing the surface to contract and start to crack.  This was a rather unusual situation for me.  I’m certainly no expert, but thought that this wouldn’t be the case until sometime in the summer when the lake dried up.  I marked a couple of locations with my handheld gps – it’s very difficult wandering around in the dark with no landmarks.

In the setting light loads of mosquitos and bugs while I ate and prepared my gear for the shooting ahead.  As it got dark – the sky was still heavily overcast and I was getting concerned about whether it would clear as forecast.  Occasionally I would go stand in the lake away from the car – for me, it’s very important to just absorb the peaceful locations and appreciate them.  People are often so focused on taking the photos that they don’t feel the location.

Getting closer to the shooting time – I trekked out into the lake.  The challenge of shooting on a lake, is that you’re limited how much gear you can take out because you can’t put things down onto the ground (lake).  So I carried out two tripods – one to act as a light stand and one with a levelling base and a skywatcher star adventurer attached to it.  Other gear I carried was the camera, speedlite, remotes, compass, gps and light sources.  I had already strapped a couple of hand warmers to the bottom of the lens just in case.

I conducted a couple of full panoramas and did a range of testing.  I always try and have a few things on my list of things to experiment with so that I can try and improve how I do things.  Theoretically some of these things work – but you don’t know till you put it into practice.

The problem about shooting this late in the season and the MW so low is you start to lose clarity of the core of the MW due to more interference from the atmosphere.

Post processing the image – well the image took longer to stitch – this is he problem about using the top level with the tracking mount while keeping the bottom level static – after a couple of hours matching control points – got it sorted.  A quick overview of my post processing.

  • In Lightroom removed sharpening
  • Small amount of luminance noise control
  • Lens correction
  • Exported as tiff
  • Stitched in PTGui Pro
  • Exported a rather large file into photoshop
  • Layer of noise control with topaz denoise – this is a fairly recent addition to my workflow.  This is because some of the adjustments later on increase contrast – and therefore typically the noise.
  • Created masks for the sky vs the land
  • Curves adjustment for the sky – I really liked it at this point and could probably have just left it at that actually.
  • Colour balancing the sky.
  • Curves adjustment for the land.
  • Colour balanced the land.
  • I then started refining the image including but not limited to
  • Black and white luminosity layer
  • Star reduction
  • Some more curves adjustments etc.
  • Graduated curves filter on the land.
  • Another noise reduction layer.
    Flatten the image and put it back into lightroom.
  • Crop and apply a slight vignette.

That’s probably 95% of the post processing.  I don’t hold secrets how I do things, but there is a lot of playing around and experimenting.  That’s why I don’t really keep a completely consistent workflow.

The Explorer