Wednesday, January 2, 2013

From Gemini with Love...

I recently had the opportunity to photograph the Geminid meteor shower.  I was in luck because the skies were set to be clear here in southwest Virginia.  I chose to shoot at a small field near the Blue Ridge Music center on the Blue Ridge Parkway just north of the Virginia/North Carolina line.
After showing the final photo, some people were curious as to how I managed to capture all the meteors in one frame.  What follows is what a person needs to know should they want to do this themselves.
The items I brought with me were as follows

Canon 5d Mark ii
Canon 17-40mm f4L(your widest lens is recommended)
Tripod
Intervalometer or Cable Release.
Extra Battery(a battery grip would be perfect for this)
A smart phone with a stargazer app.
A good radio station or an mp3 player with 4 hours of music:)

I knew that the Geminids were going to peak around 2am on the night of the shoot.  So I left the house just after midnight to head to my shooting area(about 20 minutes from my house).

Upon arrival, the first thing I needed to do was find out where in the sky the meteors were going to come from.The Radiant(the constellation in the sky that they seem to fall from) this night was Gemini constellation.  Once I found that constellation on my smartphone I had a better idea as to where to point the camera.  It is not recommended to point your camera directly at the radiant point because a falling metoer hitting your lens can cause serious damage.  Just kidding, the closer the meteors are to the radiant, they shorter they appear(think of someone shooting an arrow directly at you from 100ft away, and then someone shooting an arrow to a point 50ft to your left.  The arrow travels the same distance, but you can see much more of it when it is viewed from the side)

From here on out, all that mattered was how I was going to compose the scene.  I opted to put a tent into my scene, so I placed a light inside the tent to help me compose my scene in the dark.

Once my camera was composed, I set the camera to shoot 30 second exposures at 3200iso, 17mm, f4.  I used the intervalometer as a standard cable release and just locked it down.  If you are shooting with a lens around the 24mm length, I would recommend a shorter exposure time, as the star movement will be more apparent on a longer focal length.

Then, all you do is enjoy the show.  I ended up with several meteors showing up in the resulting images.

Before I packed everything up and left, I needed to capture an exposure for the tent.  You can get really creative here if you would like, with any sort of foreground.  For mine, I stood behind my tent and shined the light for a few seconds.

Since I had been shooting for many hours in the early part of the morning, my camera, tripod, and tent were covered in dew and frost!

Now for the boring part....

It's really easy to blend all the exposures together properly.  First I find my tent picture, adjust the white balance to the light of the flashlight, and save it(note that this will look terrible on the top half of your image)
Then I find all the images that have meteors in them, like this...
 and this...

 and this...

Once I have found all of the metoers, I adjust the image for contrast, sharpness, and very importantly, white balance(from here on out you will be working with jpegs), then save all the images in full resolution.

Next you will need to 'blend' them all together.  This is really easy, just a little time consuming.  If you are not familiar with using layers in photoshop or the gimp, make yourself familiar, then keep reading(sorry no screenshots)

I use the Gimp.  It's free, easy, and exactly like photoshop for the things I do.  All I really use it for is layers and masking, all my other edits are completed with Lightroom and Lightroom plugins.

I opened up all the images as seperate projects(you can open them up as layers if you like working that way).  I like working on them one at a time so I keep them seperate.  Then I copy and past one of the images onto another image and add a full transparent layer mask(make a note of where the meteor is in your image before adding the layer mask, because it will disappear).  Then I use the 'lighten only' brush and draw a thin line over the meteor's trail.  This will expose the meteor, and some surrounding stars, so keep it tight!  Flatten your image, rinse, repeat until all of your meteor trails are displaying nicely in one frame.

Then grab your tent image and add it as a layer.  Using the same principle as before, I added the tent into the scene.except I did not use the 'lighten only' brush, I used 'normal').  Since the treeline in my image was black in both the photo shot for the tent, and the stars, blending them together was easy.

There you have it,  an image with two parts.  The bottom part a tent with a white balance set to the flashlight, and the top part a bunch of meteors raining down in a nice cool blue sky:)




Oh and if you take all those photos from your night and blend them together with star trail software, the results are cool as well:)

No comments:

Post a Comment