Perspectives of a Canadian in the Old/Deep/New/Geographic South: This is where I ramble on about nothing in particular and post a few nice pictures.
These decrypted red Dwagons arrived from Erfworld yesterday. It took a few turns, but they made it just in time for Christmas.
The dogs keep thinking the dwagons are for them, and keep staring and expecting me to toss one to them. I’ll have to find a safe shelf to put them on.
Have I ever mentioned how much I love my HP 28S?
After taking the stats course this semester, I decided it would be nice to have a second one so that I could have one at work and one to use at home. Found a few on Ebay and bid on one. Things were going well until someone came along and ran up the price to $75, but I ended up getting it.
It arrived a couple of days ago, and today I finally made it over to Radio Shack to get some fresh batteries for it. Put them in and turned it on.
Yay, it works!
It’s in great shape and looks practically brand new. Even has the rubber pads still (the pads on mine disappeared long ago). Part of the casing around the battery cover has chipped away, which isn’t unusual for the 28S.
From the serial number (2939A05016), it’s the same vintage as my calculator (1989) made possibly a couple of months after mine was.
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
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.
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.
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.
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.
A first attempt to stack multiple shorter exposures to produce one simulated long exposure.
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.