Tag Archive | high speed

Of Gulls and GoPros

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I have written about gulls before, and exploiting their love of potato-based baits to get close up photos, and I have written about using a GoPro. This time, I combine the two, for a 120 fps free-for all, slowed down to 1/4 speed for your edification.

Along the way, I also managed to snap a few other cool shots.

This is a still from the GoPro. Note the extreme distortion and the off yellowish cast.

And here is a shot from my Canon 60D.

A Pigeon Guillemot on a oddly pleasing background.

When the sea looks like this, it is almost like a woodcut.

High-speed Arthropod Week day 4: halteres

Aug9

The flies of the family Syrphidae are some of the most accomplished of all insect aeronauts. Their agility, precision and speed are amazing to see, as they dart about flowers and freeze in motionless hovering flight. Like all winged flies, syrphids have one pair of wings only, (Diptera means “two wings”). Where the rear pair would be, there is a pair of knobbed appendages called halteres. These organs function to inform the fly of perturbations in two axes, allowing precise control of direction, speed and stability.

Without halteres, all flies become unable to maintain flight control. The precise means by which sensory information from the halteres is encoded and transmitted to the fly’s brain are not fully understood, but good physical models have been developed that implicate perception of strains associated with Coriolis forces on the beating halteres (if you hold a spinning bike tire and try to perturb it in planes perpendicular to the rotation, you will feel the Coriolis forces!).

OK, so enough physics! What do beating halteres look like? Have a look at this syrphid hovering and taking off.

It might not be super obvious, but it was surprising to me to note that the plane in which the halteres move differs by an angle of up to 30 degrees from that of the wings.

Syrphids also have high power relative to their mass, and this allows very rapid accelerations (making them difficult to catch).

haltere clean

As mentioned in my other post on wing coupling, other flying insects couple their wings to achieve formidable aerial prowess. Of course, having a single pair of wings is not the only way to be a master of the skies, as dragonflies are undoubtedly one of the most agile and versatile fliers, hovering and accelerating in spectacular fashion.

Syrphids though, with their bright coloration and super high performance enabled by halteres, high power to weight ratio, and fascinating life history, are undoubtedly one of my favorite fly families.

High-speed Arthropod Week day 3: Hop, Skip, and Jump!

Aug8

Doing these high speed videos has been a real eye-opener for me. I am amazed at how slowing down the movements of even common insects brings forth a new world to marvel at. It is reminiscent of the feeling of being a new macro photographer and just photographing insects constantly for the wonder of it all*.

So, the title refers tho the fact that every arthropod in this post displays some degree of hopping, skipping or jumping.

We start with a froghopper, the familiar Meadow Spittlebug, Philaenus spumarius. This insect, when disturbed, takes off at such a high rate that I had to record it at 6400 fps, and even then it was not totally frozen in each frame! I love the spiralling trajectory of these bulletlike insects.

This next video will show you exactly why a skipper (a butterfly in the family Hesperiiidae) is called a Skipper. These butterflies actually skip every few wingbeats, which gives their flight a real unpredictable jerkiness that likely helps them evade predators.

The following videos show a few examples of Neuropterans jumping as they take off, affording them a clear area for the downstroke of their relatively massive wings. The Green Lacewings are often referred to as “fairylike” in the appearance of their flight, as their light wing loading and bright colors make them seem like little winged sprites.

I really wanted to shoot a grasshopper hopping, but for some reason there seems to be a real lack of them (perhaps they are suffering due to our month-long drought in Vancouver)! Anyway, I hope you enjoyed the videos. Let me know which you think is the coolest!

*actually, I am still in that phase!

High-speed Arthropod Week day 2: Beetle Wings!

Aug7

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Most large beetles, in comparison to flies, wasps and dragonflies seem slow and cumbersome in flight. Perhaps this is due to their forewings being modified into protective covers for the abdomen rather than full aerodynamic partners. Instead, many beetles hold their forewings (called elytra) aloft ahead of their membranous hindwings, contributing to stability and lift at high airspeeds only (note that they often hold them at a high dihedral, which is a stable configuration).

Certain beetles have much more agility in flight, and acheive this by closing their forewings across their abdomens after their hindwings are deployed. If you have ever tried casing down a Trichiotinus flower scarab in flight, you can appreciate their advantage!

Putting all that hindwing under the elytra takes a bit of origami. Compare the folding of the soldier beetle (Rhagonycha fulva, Cantharidae) above with the ladybird below.

Beetles are hyper-diverse, and very prominent in all kinds of ecosystems, so it seems that their (on average) less agile flight has not been a big penalty. The way that they gracefully unfold their wings and reach skyward during takeoff seems somewhat hopeful to me for some reason. And however much their flight performance lacks compared to a housefly, I still remember that almost any beetle can fly a lot better than I can!

High speed imaging of jumping spider!

Aug3

Look at this beautiful Platycryptus californicus jumping spider!! She is so nice and plump! She was not always this way. When my labmate Nathan found her she was emaciated and dirty and living on the lab wall. So we fed her some blowflies!

Notice her shrunken abdomen. She is holding her legs clear of her prey while it succumbs to the venom.

Because we have fed her so well, she is now a much more attractive beast.

Anyway, today we started using a really nice high speed camera (for secret science stuff), and I needed to get the hang of working with this beastly machine. I decided a good subject would be this jumper jumping on a calliphorid fly. The videos are below. Please start the video and then immediately click the HD option and view fullscreen, as the default is kind of ugly.

So these videos are not the best in the world, as there is an annoying slowed down flickering from the incandescent light we were using (60 Hz!), but they are pretty cool anyhow. Hopefully I will do better when we get a better light source!

BTW, in both of these instances, the fly escaped. I am not even sure if the spider wanted to catch the fly, as she was already a bit stuffed. I will have to try this again with a hungrier jumper.

High speed Fly Takeoff

Feb21

We had a representative of High Speed imaging Inc. in the lab today to demonstrate some high speed cameras…So what did we record? Some blowflies of course!

Check out how these awesome flies take off:

We have used high speed cameras before, but this one was pretty impressive. This video was recorded at 4000 frames per second, and is slowed down to 30, so it is about 133 times slower than real life. No wonder they are so hard to catch!