Tuesday, September 17, 2013

The creation of Star Trails...

Speaking of star trails, the post about the shoot the other night coincides nicely with the awarding of Contest Finalist to the image, appropriately enough, "Star Trails" on Viewbug.com. I remembered I'd posted a little "how-to" shortly after I put this together and thought now may be a good time to repost for those who may be interested but didn't get a chance to see it before. So, here it is again.

While I'd love to claim that this image was inspired in my head, as with just about all of the things I've done up to this point, the idea came from a book. Harold Davis has some wonderful night photography pieces, and he's from this area so a lot of the shots he presents are local. And most are in the Pt. Reyes area. His star trail image of a similar shot in one of the books is really nice, but the boat is darker than I like. As such my goal here was to capture the trails and have the boat more visible.

I went out late Friday night and the sky was quite clear, especially for that area. However, I soon found that the wind was whipping around too much for long exposures. While I have a pretty sturdy tripod, it's not the best for real windy conditions. Any little shake with those kinds of long exposures is not good. I also had the tripod at full extension so it's exposure to the wind was even more pronounced. I doubt if lowering it would have made any difference, though. The winds were steady at 10-15mph with gusts of at least 30mph.

Heading out at 12:30 a.m. probably wasn't the best time to try this, but I was awake and excited. Once I got there I was glad I made the trek (a little over an hour from my place) as it was very quiet and peaceful. The boat is located in Inverness, on the way to the tip of Pt. Reyes. It's is a quiet little community with a couple of hotels, a store, and a restaurant/bar. It lies at the southern end of  Tomales Bay. I've been to this area on many occasions and asked a few of the locas, but haven't yet gotten a clear answer on the history of the Point Reyes.

So, I arrive and start hauling my gear out to the area by the boat. It sits on a sand bar about 100 yards behind the local store and is very easy to get to. I have my camera setup, chair, and flashlight and all is well.

I'll wrap up this part of the project fairly quickly. I used a manual trigger, light the boat with my flashlight to help get things framed, set the focus to infinity at f/4, and fire away. The wind is making things difficult, not to mention unpleasant, so after six exposures I figure I'm not going to get anything useful and decide to head home. I downloaded the files and saw right away that things, as expected, hadn't turned out. However, the trails were there, which gave me incentive to head out again the next night. What I also learned was that I needed to make sure the long exposure noise reduction function was turned off. When on, the camera works on the image to reduce noise. Makes sense given the name of the function. However, while it's working on this the shutter remains closed for as long as the original exposure. For instance, in this case, that's four minutes. What happens then, as you can see, is that the star trails become star dashes. That may be kinda cool, but not what I wanted. By disabling the function the camera immediately begins the next exposure.

I decided to get out there before sunset so I could better see the shot, and be able to get the boat focused (rather than setting to infinity). I arrived around 6:00 and got everything set up, fired a couple of test shots to make sure everything was framed and in focus, and sat down to wait for night.

One major difference for this evening was that I traded the wired, manual trigger for a wireless, programmable remote trigger. What that allowed me to do, in a nutshell, is set up the shooting sequence, press the button, and then spend the next hour and a half trying to stay warm. After a few hiccups, and the realization that the remote and the camera have to "see" each other to communicate, I settled down to let the equipment do its work.

Although the wind was far more calm on this night than the previous, thank goodness, I decided not to fully extend the tripod, or extend it at all. I figured lowering the center of gravity and lessening it's exposure to the wind would all help reduce the effects of any wind.

However it was probably 10 or more degrees cooler, and there were more clouds. It wasn't complete cover but enough to concern me. I could see the stars but they were much less bright than the night before.

I did end up having to go back to the Explorer and grab my down sleeping bag, rated at -15. Needless to say that made things much more bearable. And, having the remote trigger doing it's job meant I didn't have to stop anything to get the bag, or get out of the bag for any reason once I was warm and cozy inside.

The shooting finished around 9:00 and I headed back to the casa to start processing. I'd taken 17, four-minute exposures with a Canon 7D and a Sigma 17-70 2.8-4 Macro set at 17mm. Stacking is pretty simple, the program does the work - all I need to do is tell it which images to stack. I won't go to deeply into the details of how this is done as it's a lot of geek-speak, but it begins with 17 images that look very similar to this one, the only difference being that the stars are in different areas of each image. If you look closely you can see the trails forming.

The results were far better than I expected. The cloud cover that was present did have an affect, but not as great a I feared.

Once the program had finished stacking the images, I saw the boat was dark but I had taken a couple of shots while it was still relatively light knowing I would most likely want to mask one or more of them in during editing. That was the ticket. Another hour or so doing some additional toning and editing and you see the final outcome. A lot of fun for sure.

I may have to break down and get a more sturdy mount, though. Many of the places I like to shoot are exposed, therefore windy. My carbon fiber tripod does okay in a light wind, but anything over 15mph (common in a lot of areas around here) is going to require something more stout. Problem is, as with anything photo-related, is cost. The good ones start around $650 and go up from there. (UPDATE: I still have the same tripod and it works just fine).

I'd appreciate a favor. If you like the image, please tell your friends, have them like the Facebook page and let them know they are welcome to contact me about pricing. I have this on a canvas and it looks very sharp.

Don't forget, I'll be showing at the RAW Artists Ecompass event at 1015 Folsom in San Francisco. It would be great to see you there. It's quite an exciting time for my work and it's nice to see it getting attention. I will be joined by a wealth of other up-and-coming local artists. Tickets for the event are $15 pre-event, $20 at the door, and you can pre-order at - http://www.rawartists.org/photoworksbydon

Also, please let me know you're coming at PhotoWorks by Don at RAW Artists

Those who pre-order will entered in to a drawing to win a 32x24 signed canvas wall piece! Out-of-area folks are eligible*!

*No purchase of art necessary. Drawing will be held at the event and the winner need not be present. However, if the winner wishes to have their canvass shipped, they will be responsible for shipping costs. If local they can stop by PhotoWorks by Don Studios to pick up the prize. Winner will be responsible for any local and state taxes.

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