Tag: star trails

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Folly trails

I ventured out to the Washout area at Folly Beach with camera and tripod to do some more star trails. It wasn’t quite as dark out there as I expected because of the street lights, but it does offer unobstructed views of the sky. The sea breeze also helped keep condensation from forming on the lens, so I was able to do a much longer exposure.

After finding a nice spot shaded from the street lights, I pointed the camera east-ish and let the camera shoot for an hour. Finished up with 122 30 s frames that I combined into this image

Folly trails

If you look really closely (easier to see on the full 3450×2308 image) there are a few lines of dots going across the middle of the image. Those are the blinking lights of some planes flying by at high altitude.

While I was waiting, I managed to see a few meteors streak by. Unfortunately none of them were where the camera was pointing.

Now I need to find a place with an unobstructed view of the northern sky.

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More stacking

A little more internet searching led me to a suggestion to use GIMP’s Lighten only mode for combining layers.

This is the same image from yesterday, only using Lighten only to combine the layers.

A photo of star trails composed by stacking shorter duration photos

I also found this great set of GIMP plugins that someone wrote for processing astronomy type images. It’s the ‘Set mode for all layers’ script that I was most interested in.

My third attempt at stacked images for star trails (the second attempt was all out of focus). This time I put the camera on burst mode, 30s exposure (the longest exposure my XT will do before bulb mode), f/3.5 and left the remote trigger locked down. This is Orion streaking through the sky, composed of 58 images.

Stacked star trails

The much shorter exposure and wide open aperture gives a much darker sky and brings out a lot more stars. It also means a lot more images to process: 60 images for a 30 minute exposure. Loading all those images requires a computer with lots of RAM.

Good thing I bumped the memory in my computer up to 24GB. The computer hardly breaks a sweat when I ask GIMP to load that many images (at 3456×2304, GIMP says each image takes up 71MB).

Now I want a wider angle lens for my camera.

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Stacked star trails

A first attempt to stack multiple shorter exposures to produce one simulated long exposure.

Stacked star trails

This is composed of 4 images, ~10 minutes each, f/7.1 ISO 400. Loaded each image in GIMP using Open as Layers and combined each layer using the Hard Light mode. It seemed to give me the best result. Switched the image to Grayscale mode and saved.

The really bright streak is Jupiter.

One of these days I’ll make the effort to venture out to some place darker than my back yard.

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Star trail experimenting

More experiments with star trails

43 minute exposure, f/13 ISO 100, camera noise reduction on. The lower ISO definitely helps with image noise, but combined with light pollution from city lights and the rising full moon, most of the fainter stars are lost.

Star trails from a 43 minute exposure with a large tree in the foreground.

20 minute exposure, f/13, ISO 100 camera noise reduction off. The bright streak at the bottom is Jupiter. Lots more noise without the camera noise reduction, but you get the image in half the time and get a more shooting time out of your battery.

Star trails from a 20 minute exposure with some trees and power lines in the foreground.

It’s going to be really hard to get good star trail photos in the middle of the city anyway, but it seems like something between f/7.1 – f/11 and ISO 400 gets me some pretty nice shots with my camera.

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An attempt to capture Geminids

Thought I’d try some long exposures this evening and maybe see if I could capture some Geminid meteors streaking through the sky.

Being inside the city and with a full moon out, I knew it was going to be a challenge. It might look dark outside, but city lights and the full moon can make long exposures look bright as day.

21 minute exposure, f/11 ISO 400. Had to knock down the brightness quite a bit.

No Geminids

Although I didn’t get any Geminids on camera, I did get to see a few streak overhead. Always cool to see. Got a couple other photos before condensation built up, but they didn’t turn out quite as well.

Perhaps another attempt tomorrow night.