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I’ve been working on some electronics and software to do precisely timed photography setups. One of the issues I encountered was that I seemed to have a lot of unpredictability in the delay between when I fired the shutter signal and when the shutter opened. I took some measurements to find out what range of shutter lag I needed to account for when calculating trigger times, and once I got setup it quickly became clear that there were two delay modes I was seeing: a short, very predictable delay, and a much longer and much more varied delay. It didn’t take much longer to realize what the difference was between these mode, and that this was what was causing my problems:

The D90 has a very predictable shutter lag; When it is ready to go. When the display is still active showing the image from the previous shot, there is a much longer shutter lag, and it varies a lot. So, when precisely controlled timing is required, you need to make sure the display is off before triggering. This can be done by either waiting for the shooting info display to turn off, or half-pressing the shutter button. In my setup, I wired the half-press and full-press together, because I didn’t think I’d have any reason to command a half-press. In the future, I think I will wire them both to be controlled separately, so that part of the sequence can be to send the half-press command early enough to ready the camera before sending the full-press shutter command.

The Setup

I controlled the camera via the remote shutter cable input. I had both the half-press and full-press wires connected together, so that both were shorted at the same time to the common wire with a FET. I used a microphone to detect the shutter, and connected both the trigger signal and the audio signal from the microphone to an oscilloscope to measure the delay.

The Results

When the display was still on, the shutter delay was around 210 ms. It varied a lot. At least 20 ms, probably more, but to be honest once I figured out what was going on I didn’t really record measurements for this case.

When the display had turned off, the delay was 70.2ms, +/- 0.5ms.

The capture below shows the sequence. The camera was set for 1/5 shutter time, or 20ms. I’m fairly sure that the first long sound is the mirror opening, and then the is a quick sharp sound which is the first shutter blade opening, followed 20ms later by the second shutter blade following it to block the sensor. The time between these two pulses varies as it should with exposure time.

As you can see here, the bulk of the shutter appears to be taken by the mirror movement, which takes around 40ms. It is possible that there is something else going on that the camera would have to wait for anyway, but I have to wonder why they don’t have a mode to hold the mirror open to begin with. Even in live-view, where the mirror is normally up, the D90 closes the mirror when you press the shutter button, then opens it again to take the shot. I’ve no idea why they would do that.

This weekend, I made another attempt at photographing fire, and this time got much better results. I have seen some really cool burning beverage photos on flickr recently, and I wanted to try one of my own. Conveniently, I have a whole bunch of martini glasses laying around. When I put one in front of a white background and illuminated the background, it looked awesome, and I knew I was on to something. A key difference from the previous flaming ice shoot is a change of fuel: I used white gas that I had for my backpacking stove instead of the vodka I used last time. It burns MUCH better. I was an idiot for trying to do this with vodka. I have feeling that when I go buy some lighter fluid and try that, I may find that I am an idiot for using white gas, because the camp stove fuel burns DIRTY. It leaves a sooty grime very quickly, and I was constantly cleaning the glass. I hope (though I haven’t tried yet) that lighter fluid will burn cleaner.

This is the setup in my living room:

You can’t see it in the setup shot, but on the floor behind the glass is an SB-600 flash, with a blue gel, pointed up at the white background. Except for the flames (which were surprisingly bright) this was the only illumination. Because the pop-up flash fires in order to trigger the remote SB-600, I had to tape a piece of glossy white paper over the pop-up. The paper stood out an inch or two in front of the pop-up, at a 45 degree angle. That way, the pop-up light was re-directed so it didn’t shine on the martini glass and reflect back to the camera, but the light from the pop-up could still reflect off floor, walls, etc enough to trigger the SB-600.

When I started friday night, the only thing I  had on hand for a table to put the glass on was a  piece of white foam board. This worked OK, but the fire reflections on the foam board kind of bothered me. So Saturday I ran some errands and bought both a black foam board, and a mirror. Both of these worked better than the white, but I really liked the shots with the mirror.

A shot from the first set with white foam board:

Then, with the black foam board:

Then finally, with the mirror as table:

While I was shooting these, I really liked the blue. Then while processing the photo above, I tried getting rid of the blue by selectively de-saturating the image, and I REALLY liked it. So, now I’m a bit torn, but I think if I had to pick only one flaming martini image, this is it:

I set out to capture a cool fire and ice shot tonight. I didn’t have a lot of success with that; I think I need a better burning surface, and maybe a better fuel. However, I thought the melting ice made a cool animated gif! The last chunk of each cube really went out in one quick pop. Not sure why that is.

That’s a plate of vodka, in case you were wondering. I had several problems getting a decent shot:

1) The plate is kind of convex, so the vodka wanted to be on the outside, not with the ice. I really want the opposite.

2) The plate is not ideal for a background. I think I want a piece of glass on black background…maybe? ‘

3) Vodka just isn’t that great a fuel. It has to have sufficient quantity, and be warmed in order to burn at all.  Two bad it wouldn’t burn cold, because when I pulled it out of the freezer it was nice and syrupy and would actually stay where I poured it.

For a brief moment the thought, “Can I build a still out of what I have in my kitchen?”,  did cross my mind.

On the day we left Zion, we drove through the tunnel and out the east entrance. On the other side of the tunnel, we stopped to explore a frozen riverbed, and spotted a herd of a dozen or so Big-Horned Sheep.

I had read on an internet forum that Coral Pink Sand Dunes State Park was worth a visit. It’s fun to climb sand dunes, and they often make for nice scenes, so we figured we would head out of the park, stop by the sand dunes, and continue home from there. I wouldn’t say I regret going, but the dunes were not exactly spectacular, either. Kelso Dunes in Mojave, or the Mesquite Flat dunes in Death Valley are both a lot cooler places. For one thing, the dunes here were not very extensive. There were really only two peaks worthy of mention. Secondly, they were inhabited by off-road vehicles, with accompanying tracks and noise. When you walk in from the parking lot, there is a small section of sand fenced off, with a few openings. At the openings, there is a sign which doesn’t forbid walking around the dunes; it just says it may be dangerous, and suggests maybe you shouldn’t, or at least be careful. We decided to trust the kids on ATVs not to run us over and walked out to climb up the tallest dune. We climbed it. We watched the ATVs ride around, took some photos, then headed back towards the picnic area to make some lunch before heading to Vegas for the night.

After we left the park, we crossed over into Arizona. As soon as we did, the pavement ended. My first thought was, “Maybe we’re on the wrong track here?” But, no worries. The dirt was smooth, and 5 miles later the pavement re-appeared.

I spent Thanksgiving with Mary and her family at Zion National Park in Southern Utah. It was quite cold while we were there, and we had a really good time. It snowed the day before Mary and I arrived, so everything was still covered in a dusting of snow, and it was cold enough that wherever there was water to freeze, there was ice!

On Friday, Mary, her father, and I hiked up to Angel’s Landing. This is probably a really awesome hike any time of year (although I bet it is ridiculously crowded at peak season). With the snow and ice when we were there, it was the most fun I’ve had on a trail in a while. First the trail goes through a canyon, and then up two sets of steep switchbacks. Then you double back on the ridgeline above. This is where it gets awesome. It is a fairly technical trail with a lot of scrambling along a sometimes narrow ridge.  However, there is  a chain installed along all of the sketchy parts, so it really isn’t that bad. With the ice, it was still a bit of a challenge in spots even with the chain (just enough to be a lot of fun, as long as you are in reasonable shape, and not terribly scared of the heights).

The first really interesting part of the hike was at “Walter’s Wiggles”. This is the second, and the steepest, set of switchbacks, which take you up to the ridgeline. For us, they were completely covered over with snow and ice. The best part though was actually on the way down. On the way up, it was passable. By the time we had come down, it had re-frozen, and was super slick. The whole canyon was filled with hilarity. I thought it would make great inspiration for a mario kart track. The canyon echoed with people laughing, owws!, and general chatter. A group of kids was having a great time sliding down each segment. One of them was a strong supporter of the “penguin style” belly slidel. Adults were falling constantly, some stoically insisting on getting back up and walking again (until they fell again), and others just giving in and sliding down. It was all out comical.

After getting up the wiggles, there is a bit of up and down along the ridge line, out to the landing. There are some flat part, some steep parts, and a lot of good views!.

This is taken while climbing of the last bit of ridge, looking back along where we came:

Now I will leave you with a quick video clip of the wiggles:

I never really loved the beach when I lived on the east coast. For whatever reason, I like it a lot more now. Wandering the PCH has become one of my most popular ways to spend a bored afternoon. Today I started out for Santa Monica, but ended up at Malibu Lagoon instead. Perfect weather, nice scenery, and lots of activity. It was a good chance to try out the new telephoto lens some more. I still love it. It lets me get in soo much closer to a distant subject. Check out the sea gull, which was taken at 170mm…super sharp (and it is at original sensor resolution, just cropped).

I sat and watched these surfers in front of the sun for a while. I might have lost a bit of my vision in the process, but I really like these:

Check out this well-polished bi-plane:

The seagull:

Lots of dogs (of which this is one):

And a paddle boarder, riding a wave. Love the wetsuit and trucker hat!

Paddle boarding looks like something I want to try. Standing up high above the water and paddling down the coast…looks nice.

While surfing the interwebs tonight, I came across a silly stop-motion video about, well, stop-motion. My first thought was, “That must take freakin’ forever!”. Or does it? How hard is it really? Suddenly, I wanted nothing more than to try my own stop motion animation. I really didn’t want to mess with clay characters, or a plot, or a little set. I just wanted to try moving some letters around. So, here it is below (or view it on flickr):

The first thing I did was start cutting paper letters. Actually, I cut one letter. Then I said to hell with this, and set off trying to find a quicker path to forming words. Scrabble! Perfect. I have a letter set right here.

So I put up the camera, a flash, and pointed it at a black foam  board. First lesson: Don’t use a flash, if you can help it. The flash can only cycle so fast, and this limits the rate you can take pictures. I could move things faster than the camera could take photos.

Second lesson: Check your exposure, ON A COMPUTER SCREEN, before you capture the entire scene. I got fooled by the camera LCD into dramatically underexposing. This just meant I had to correct all the shots later.

Third lesson: Set the camera resolution to something lower. You don’t need 12MP images to create a 640×480 video. Everything goes slower with the larger file, so just shrink it down from the beginning.

Fourth lesson: You really do need small movements. My video is jerky as hell. Downright amateurish. I guess I wasn’t patient enough, but I didn’t really have a good feel for how small motions needed to be. Also, I guess I could have made the text a little straighter. And, all of the “letter flying in” frames for the top row failed miserably, because the letters were off the top of the screen.

I cannot imagine doing a full-length stop-motion film, but a few minutes really isn’t that bad. It is strangely satisfying. In fact, I spent a lot more time and got a lot more frustrated with the editing of this clip than I did with the shooting. A lot of that frustration was just figuring out how to do it though, and would go a lot faster on the second try.

iMovie is crap. A pain to use, and it would not let an image in a slideshow have a duration less than 0.3seconds. Further evidence that there is just no reason to use MacOS. I ended up using two things: VirtualDub to piece the still frames together, and Windows Movie Maker for the final editing, adding the end credits, and overlaying audio. It was a somewhat tedious process getting the still images all ready, but virtual dub will quickly take a sequence of numbered JPEGs and combine them to a movie. Irfanview came in very handy for generating these numbered sequence. For example, if I wanted to repeat a frame, say IMG_0527.jpg, I would create copies named IMG_0527_2.jpg, IMG_0527_3.jpg, etc, and then use irfranview to batch rename these into take2_1, take2_2, etc. so that VirtualDub would read them correctly.

The next problem I hit was the sound effects. I used my Blackberry to record the scrabble pieces splashing across a table, and the file was a .amr file format. wtfmate? A little googling, and I found the Moble AMR Converter on free-codecs.com. OK, so now I have a wav file. BUT, Windows Movie Maker won’t allow multiple audio tracks, and I’ve already used the audio track for the music. For this, I had to encode the movie without sound effects (just music), then open that video and add the sound effects in a new project and re-encode the final cut. Easy enough.

Total camera time: ~80 minutes.

Total editing time: ~150 minutes.

Total animation length: ~90 seconds (and the second half isn’t really stop-motion at all, so really ~40 seconds)

Production minutes per animation minute: ~350

That was fun! Now it is quite late, and I should probably get some sleep.

Last week, I got a Nikon 70-300mm VR lens. Tonight when I got home, I found my new Manfrotto 190XPROB tripod and a Manfrotto 222 joystick head waiting at the doorstep. I put the new lens on the tripod, and love how stable and easy to adjust this thing is, it is FAR superior to the cheapo tripod I picked up at REI last year. On the down-side though, the weight is more than doubled (at a little over 5lbs, I think), and I’m not sure I REALLY want to add this thing to an already heavy backpack. In any case, once I got bored of the novelty of slewing the joystick around, the search began for a subject to photograph. After scouring the apartment for random objects, I ended up with these two:

As for the lens: So far I’m giving it two thumbs-up. The VR is noisy. It turns on when you half depress the shutter button, and turns off a while after (to save power, presumably), and it makes a hell of a lot of noise when it “clicks” on. However, I really don’t care, because it does a hell of a job. I can take 1/30th exposure shots at 300mm with reasonable success. It is sharp. Sharper, I think, than the 18-105mm VR kit lens that I got the with the D90. And finally, I’m really happy with the depth-of-field you can get at the long focal length. I guess if you can’t afford an f2.8, just back up and go longer.

A while back I saw some pictures on flickr looking, from above, out over Ventura from the north-west. This evening around sunset I went to check out the overlook spot for myself. The place is called Grant Park (google map), and it has a great view both up and down the coast. My recent reading still has early California at the forefront of my mind, so while I sat on the hill waiting for twilight and watching the constant stream of cars down the 101, I couldn’t help but imagine what it must have looked like to the first person to climb up the hill and look out over the region. Surely someone must have drawn the same view before the Ventura mission turned into a city?

Just for fun: