Red Planet Star Trails Final

This was taken from the side of the Caldera Colorada volcano, near Masdache, Lanzarote. There is a 45 minute walk round the base of the cone. One side is an unusual rich red, made up from cinder, rich in iron oxide.

There is a story associated with this image. I had finished one hour 44 minutes of 2 minute Star Trail exposures. I put the lens cap on and did a 2 minute dark exposure for noise reduction. Then I tripped and fell against the Tripod, grabbed it to try and save the camera but over it went with me on top of it. The amazing thing is there was not a scratch on Camera or lens and both work perfectly. I was also holding a smartphone using the torch app and that was undamaged. I had only a few minor cuts. You might say I had an argument with a Tripod and the Tripod won.

I had with me an HTC Android Smart Phone with the Google Sky App. This enabled me to locate the pole star while there was still light. The foreground comprises an HDR image taken while there was still light. With the Camera and Tripod locked in position the star trail images were taken later when the stars were out.

I used my Interval Timer and set the camera at ISO 200 and bulb and the timer at 2 minutes at f3.5. The lens was a Samyang 8mm fish eye.  I set the timer to take images for 1 hour 44 minutes. I use software to stack the star trail images. There are a number of free programs available though I use http://www.startrails.de/html/software.html

In the end there was too much light in the first 10 minutes of exposures. I used 47 images or 1 hour and 34 minutes worth. There was still enough light to get a little blue in the sky which I wanted.

Note that here is distortion in the image due to the fisheye lens pointing up which curves the landscape up from the sides. This was exaggerated with the processing where I used the clone tool to add to the curve on the right to remove light from a town and also on the left to remove an over bright area in the sunset direction.

I took a dark frame. This has to be taken at the same time and place. The reason is that with long exposures the sensor will produce hot pixel noise which will be the same as for the star trail images if taken for the same length of time and crucially at about the same temperature. The stacking software can then automatically subtract that noise from the final blended image.

The circular pattern is formed by pointing the camera towards Polaris the Pole Star near the Plough. As the Earth turns stars more above the pole do not appear to move as much as those more above lower latitudes.

All the settings and equipment were as follows

- Sony A700 Camera.

- ISO 200, f3.5, 1 minute 59 seconds, 8mm. 1 second between each shot set in the timer.

- Long Exposure and high ISO noise reduction set to off. Otherwise the Camera would take One minute and 59 seconds between each shot for its own noise reduction resulting in great gaps in the Star Trails.

- Samyang Fisheye lens 8mm.

- Tripod.

- Interval timer

See this post for a review of this Timer

http://edwinjonesphotography.com/blog/2012/5/timer-interval-remote-review

Post Processing

For the Star Trails the stacking software works on jpegs which are then saved as a Tiff.

After opening in Photoshop some extra detail was brought in with Topaz Adjust  Vibrance presets group and Dramatic2 preset.

The Star Trails were brightened with adjustments in curves levels, contrast and brightness.

Saturation magenta and reds reduced to tone down the purple shade of the light pollution on the right applied with a layer mask.

After flattening the image duplicate layers were brought up to sharpen and then apply Noiseware Pro. 

For more contrast and brightness in the stars Unsharp mask was used with settings of amount 49 and radius 49.

For the foreground this was a standard 3 shot HDR taken with light still in the sky.

After opening in Photoshop some extra detail was brought in with Topaz Adjust Vibrance presets group and Clarity preset.

 Adjustments were made in levels to darken a little.

Vibrance  increased 39 points.

Saturation reds plus 18 points.

A little sharpening and Noiseware Pro.

For more contrast and brightness in the landscape unsharp mask was used with settings of amount 49 and radius 49.

On the Star Trails image I selected the sky using the quick selection tool. Then I copied the selection and pasted it in to the foreground HDR image. I used the move tool to line it up with the foreground.  Some pixel level cloning was done along the line of the join to remove some bright areas which came across from the foreground image

BEFORE AND AFTER

Below are the Before and After images. First the HDR image of the foreground after Photomatix but before other processing. Then the Star Trails Image after merging of the frames but before other processing and then the final result.

Tonemapped Foreground

Red Planet Star Trails Tonemapped landscape

Merged Star Trails image

Red Planet Star Trails Original Stars image

Star Trails image after editing

Red Planet Star Trails Stars after editing

Final Image

Red Planet Star Trails Final

For licences see Red Planet Star Trails

Edwin Jones