Josef “Jeff” Sipek

Stellafane (2016)

Last weekend we drove to Wikipedia article: Springfield, VT to attend the Stellafane Convention. In short, it’s two and a half days of camping, astronomy and telescope making talks, and of course observing. I brought my camera (D750), two lenses (24-70mm f/2.8 and 70-200mm f/2.8), and a tripod. Over the two and a half days, I ended up taking 400 shots of just about everything of some interest. I post processed about 60 and created a gallery. I’m going to include only some in this post, so make sure to check out the gallery for more shots that just didn’t fit the narrative here.

Thursday

Thursday was mainly about arriving in the late afternoon, setting up the tent, and doing some observing once it got dark. Photography-wise, my primary goal for Thursday was to get some sky images at 24mm. I tried some long exposure (657 seconds) to get some star trails:

There was a decent number of people walking around with red lights (so as not to destroy night vision), so a number of my shots ended up with some red light trails near the ground. (That’s that wobbly red line.)

I also took a decent amount of short exposures (10-16 seconds). At 24mm on the D750, 13 seconds seems to be just about when stars start to turn into trails.

This is the only staged shot—I intentionally left one of our red flashlights on in the tent to provide something interesting in the foreground.

Here is our tent-neighbor and friend looking up at the sky. He didn’t actually know that I was taking a shot of the milky way, and I didn’t realize that he managed to sneak into the frame. The trees got lit up by some joker driving around with headlights on. I expected that to ruin the shot, but it actually worked out pretty well.

Friday

Friday is the first full day. I started it by hiking to the other side of the site, which not only sports a nice view, but also nonzero phone and data coverage:

The original club house is there as well in all its pink glory:

The last, but not least, building there is the turret solar telescope:

Right next to it is the location of the amateur telescope contest. Yes, people build their own telescopes and enter them into a competition to see whose is the best. This year, the most eye grabbing (in my opinion) was a pair of scaled down reconstructions of the 8-inch Alvan Clark refractor. Here’s one of them:

I couldn’t resist taking a couple of close-up shots:

Heading back toward the main site, I walked past the observatory set up in such a way as to be handicap accessible:

After a breakfast, it was time to go off to the mirror making tent. I think that every year, there is a series of talks and demos about how to make your own telescope mirror.

The speaker letting an attendee give mirror grinding a try:

And a close-up of the eventually-to-be-mirror on top of the grinding tool:

Fine grinding demo using a glass grinding tool instead of the plaster one:

After lunch, there was a series of talks about a lot of different topics—ranging from digital imaging, to “crowd-sourced” occultation timing.

Between talks, I noticed that one of the attendees erected Federation flags in front of his tent:

Once night rolled around, it was time for more observing. I took a number of milky way shots. They all look a bit similar, with the only real difference being what is in the foreground. Of all of them from this night, I think this is my favorite—there were a couple of people standing around a telescope talking with their flashlights on.

Saturday

The second full day of the convention began with mechanical judging of the telescopes.

Somehow, I ended up drawn to the twin-scopes; here’s another detail shot. You can see a little bit of motion blur of the governor:

The day program was similar to Friday’s—the mirror making talks and after lunch a set of talks on various topics.

The evening program consisted of the keynote, raffles, competition results, and other customary presentations. The sky was completely covered with clouds till about 1am at which point it started to be conducive to stargazing. Oh well. Two clear nights out of three is pretty good.

Sunday

Sunday is all about packing up and heading home. During breakfast time, I ended up walking around a bit and I got this image—with the food tent in the foreground, the handicap accessible observatory near the background, and the McGregor observatory with a Schupmann telescope in the very background.

So, that’s how I spent the last weekend. I’m already plotting and scheming my next astrophotography adventure.

D750 Star Trails

I have tried star trails photography once before—7 years ago. Back then I was using the D70 which was a good camera but there were two problems with it for astrophotography: first, its CCD sensor wasn’t the best at higher ISOs, and second, long exposures were not possible because of some interference (thermal or electric) which resulted in ugly purple fringing. That experience made me not really bother with astrophotography—hence the seven-year hiatus.

A week ago I decided that I should try again with my D750 and the 24-70mm f/2.8 lens. Since they are both significantly newer than my old setup and are superior in just about every way, I thought why not try again and see exactly how much better the results would be.

I ended up with only three shots worth sharing. As always, I made a gallery with them. The one difference from the other photo galleries I make is that I will continue to add star photos to this gallery until the end of the year (when I plan to make a 2017 gallery).

After setting up the camera in the general direction of Polaris, I needed to figure out the exposure. So, I cranked up the ISO to 10000 and took a 5 second test shot at f/2.8. The hope was to see how the sky exposed, and then “trade” the ISO for time to get the same exposure but less noisy and with star trails. (E.g., changing the ISO from 10000 to 160 is 6 stop difference, so the shutter speed needs to change 6 stops in the other direction to compensate. That is from 5 seconds to 320 seconds.) When I viewed the image on the back of the camera, I was blown away:

While there is certainly noise in the image (which you can’t see in the resized version) and the composition is not great, it’s cool how both the foreground and the sky are equally well exposed. The trees are essentially light-painted by the neighbor’s driveway lights which were on at the time. And before you ask, no, that’s not the milky way, that’s just a wispy cloud.

Then, I proceeded to take a back-to-back series of 15 second exposures. After five minutes (21 shots), I was sufficiently bored to try something else. After heading back inside, I stacked the 21 shots using StarStaX. Here is the resulting image (slightly tweaked in Lightroom):

The orange blur on the right of the image is a small cloud that moved across the frame during the five minutes without me noticing. Unfortunately, there is plenty of light pollution to the northeast of us because of the neighboring city of Wikipedia article: Nashua. I am definitely going to experiment with stacking.

The final couple of shots I took were all various long exposures—ranging from 8 to 20 minutes. This is one of the 20 minute exposures:

Again, the light pollution from Nashua is unfortunate.

The 74 degree horizontal field of view at 24mm is pretty good. Of course, a wider lens would provide for an even more interesting shot. For example, a 15mm focal length would produce a 100 degree horizontal field of view. With that said, I am certainly going to experiment more with star trail photography—even if I have “only” a 24mm focal length.

Star Trails

It was a dark and stormy night…wait a minute…it was a clear and calm night; the night sky glistened with the light from thousands of streetlights releasing billions upon billions of photons, only to be scattered by the atmosphere and to rain down upon Ann Arbor — to pollute the otherwise perfect night sky. So, Jeff, a twenty-odd year old who can be best described using Dungeons & Dragons character alignment as "chaotic good," decided that it was time to escape the particle bombardment to attempt the astronomically difficult, and equally arcane, task known as astrophotography…

Anyway…Here are the exposure details and the photos (from February 24, 2009):

826 seconds
f/3.5
ISO 800
Nikon D70
18—70mm @ 18mm (35mm equiv: 27mm)
Location: McCollum Rd, MI

Stars

Here’s the same photo, but with a very well known constallation outlined.

Ursa Major

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