Sample images of what can now be done with the ultra-high shutter speeds with high-speed flash sync.
A Drop in a Bucket, in a Sink, I mean in SYNC![edit | edit source]
These images were taken with the new high-speed shutter override option.
1/10,000 second, Manual mode, f/3.5, flash manual at lowest output, +4 diopter close-up lens, subject distance approx. 10 inches (25cm), room lights and lights above sink all turned on.
Notice the greenish rectangular highlight in one of the drops. That is the fluorescent light over the sink. Giving these high-speed shots the appearance as if taken in available light alone. I really didn't spend any time learning to use this feature. Right after downloading Fingalo's Alpha build I popped it in the camera and headed to my kitchen sink to test it out. Some of these are within the first 5 shots taken. I got so enthralled I must have fired off another 40 more, then selected a few favorites from the bunch. These are just downsized images of the full frames, slightly cropped to get rid of some empty space around them so they look a little nicer. (I just did a hunt to see what the fastest shutter speeds are available on any other commerical digicams, the $2000-$20,000 ones go up to 1/8000 shutter speeds. And that's with the crippling limitation of using a focal-plane shutter so there's no high-speed flash sync. :-) )
On further investigation by others, it now appears that while the CCD electronic shutter timing is at (approximately?) 1/10,000th of a second duration, the flash is firing at speeds up to 1/60,000th of a second duration!! (see Dremel-drill speed test below) The CCD timing cutting out any blur from ambient lights and the flash freezing the motion. (Wow!)
This clearly shows the highlight from the fluorescent lamp above the sink. The other images also catching the greenish fluorescent ting. Giving these photos that available-light quality. I like the way that the back out-of-focus splash-ring from the previous drop is being refocused into clarity by the suspended drop that's next to hit. Very zen and fractal-like. The basis of optics and photography being performed by the inanimate(?) subjects themselves. :-)
I saw this one go by as I was taking shots and had hoped it would have turned out better. The drop still in shape but the bottom half already exploding beneath it. It's so hard to focus on running blurry water! Try it sometime. :-)
Looks like the typical milk-drop high-speed flash image that we all grew up with in photography and high-school science textbooks showing how the invention of xenon flash could show us things we never knew. And a fitting closure to this sequence.
Dremel-Drill Shutter/Flash Speed Test(s)[edit | edit source]
This image from an S2 IS PowerShot camera was submitted to test the true speed of the new ultra-shutter-speeds. However flash was used, so it is a better indicator of the flash-duration than shutter speed. What is important here to consider is that the camera's own flash synced with this high-shutter speed, extinguishing all ambient light from ruining the exposure and providing for optimum detail. Also, as the calculations will show, revealing some surprising results.
A smaller well-defined highlight at the very edge of the disc's abrasive, one with easily discernible starting and stopping points, was used to better measure the angle of rotation. This way the measurement wouldn't also be thrown off by the diameter of that highlight that moved during the exposure.
Dremel Drill: 30,000 rpm = 500 rotations per second = 1 revolution every 1/500th second.
Motion blur: 2.97 degrees, let's safely round that to 3 degrees = 1/120th of a revolution.
This means that 120 units of measure can fit into a 1/500th of a second rotation.
500 x 120 = 60,000
The highlight's motion blur occurred during an exposure of 1/60,000th of a SECOND!
The image above is not just of a 1/8,000th nor even a 1/10,000th of a second exposure, but of 1/60,000th of a second effective shutter-speed. Xenon flash units usually control their flash output by duration rather than output level. So when used on the dimmest setting these cameras are shortening the flash output to 1/60,000th of as second.
How's that for high-speed flash-sync photography?
- [Addendum: It has now been discovered that these high CCD-shutter (as opposed to flash duration) speeds are F-stop dependent. In the same way that the camera's own firmware will only allow a shutter speed of 1/3200 at F/8.0. (On typing that just now, the camera's fastest native speed of 1/3200 seems agonizingly slow compared to the speeds we've been using and enjoying.) Aperture dependent: meaning CCD-shutter speeds of 1/8000 to 1/10,000 are only available at widest aperture. At smallest aperture f/7.1 - f/8.0 then CCD-shutter speeds as fast as 1/50,000 to 1/64,000 are available. That's yet another 8, 1/3EV steps. It has been very difficult to determine why some people were getting higher shutter-speeds during random testings. The only way to be certain is to use available-light sources alone (no flash). At F-stops that small and shutter-speeds that fast the light intensity has to be extreme, to say the least. Much brighter than sunlight. Once this new range of shutter-speeds are added to the CHDK Menu "Shutter Override" then high-speed flash will be able to be used as the light source for even more precise motion-stopping effects. The CCD-shutter matching the flash-duration and effectively obliterating any detail-smearing blur from ambient light sources completely.]
I have since been investigating other uses of high-speed flash on the internet, and ran across this little discussion, when someone was enquiring about photographing shot-gun spread-patterns from the side, and how fast of a flash would be needed. The reply is rather appropriate for this photo. They compared the edge speed of a Dremel-drill cut-off wheel with ballistics speeds.
I guess this means that if you wanted to, and had a way to sync your camera to a rifle shot, you could get one of those spectacular images of a bullet ripping through a playing-card, edge-wise.
Also worth noting in my net searches, most "high speed" flash units on the market rarely go above 1/50,000th of a second, more commonly about 1/20,000th to 1/30,000th of a second, at exorbitant cost.
1/60,000 Shutter-speed With CHDK "AllBest" Build[edit | edit source]
Well, the results are in. These were taken with the new AllBest CHDK build. Set at 1/60,000 of a second shutter speed, and testing various f/stops and flash-output levels. You can tell by an absence of any greenish highlights from the fluorescent light above that only flash was illuminating the water this time. The second image here was taken at f/8.0, so the flash had to be raised to the 2nd level of output. Much brighter and therefore a much longer duration than the previous images of 1/60,000 flash duration. But as you can see, this time the CCD shutter alone was able to stop the motion just as crisp as if the 1/60,000 of a second flash was used to halt all motion. I'd say that pretty much confirms that high of a shutter speed. Maybe it's time for a new battery of dremel-drill tests.
- 1/60,000, f/8.0, real shutter speed presumed 1/60,000
High-Speed BIC® Lighting[edit | edit source]
Inspired by some interesting photographs done by Alanq at the CHDK Forum, here's some macro shots taken of a BIC® lighter using the ultra-fast shutter speeds. The one of the mushroom bubble is pretty interesting. I like how the uneven combustion that's starting around the perimeter as well as the little flecks of hot flint acting as highlights make it look as if it's a bubble made of glass or liquid. It's just igniting butane gas.
True shutter-speed is unknown in both these instances because these were pulled out of many frames taken during extended bracketing sequences. A +4 diopter close-up lens was used to allow for some photography working-distance while the camera's own lens was zoomed in (tele-macro mode). The lighter was held at an approximate manually focused distance (not always successful to hold the lighter at the right spot with repetitive attempts to light it). The camera's shutter-button held depressed with one hand while lighting the lighter continuously with the other. Out of 300 or so frames there were about 10 fun and interesting ones like these.
Shutter Speed Test by Laser[edit | edit source]
Inspired by the Dremel-Drill method, and a post in the CHDK forum where someone mentioned that a scanning laser beam might be a more reliable method (when photographing an oscilloscope display failed, due to phosphor luminosity lag (fluorescence vs. phosphorescence)), here's another way.
This image is a many many layered composite of all the frames from one burst-bracket sequence.
Each frame rotated so the consecutive shorter shutter speeds would follow one another for easier viewing.
See text below, which also explains the accompanying shutter speeds.
Layer of wax-paper rubber-banded over the open end of the filter adapter tube. So it will act as a rear-projection screen as I shine a laser light on it.
Camera set to:
Super macro mode, focused on the wax-paper rear-projection screen.
A loupe precariously balanced in front of it so as to focus the laser beam to a small point of light that will be reflected off of a fast revolving mirror. (Without a magnifier in the path then the laser light is ungainly huge, even when projected onto paper using normal front projection methods. It had to be reduced to get any accuracy whatsoever, or they were just misshapen smears that changed size and brightness greatly depending on what arc of the circle they were in. This still happened a bit when focused but not as much.)
In front of the loupe is a hand-held hobby-drill (the label claims it should run at 16,250 rpm, but I doubt it).
On the end of the drill is a small square of 1st-surface mirror affixed to a grinding bit. If attempting to duplicate this method (vs. this slap-dash hand-held just to see if it works attempt), use as small a piece of mirror as you can focus the laser on. The smaller the better so its mass, if off-balance the slightest bit, won't cause the high-speed drill to dislodge it while it is spinning. When gluing the mirror flat to a grinding disc, cut-off wheel, or whatever, you need to have the mirror lay at a small angle, so as it rotates around its axis the laser-light bouncing off of it will move in a circle. If the surfaces are too flat when gluing mirror to grinding-tool you can get away by inserting a small piece of needle between one edge of the mirror and the mounting surface to tilt it at a slight angle (as I did), filling the gap between all with a slightly thicker layer of strong adhesive. If your cut-off wheel or grinding bit has some tilt of its own, this may not be necessary. [Aside: This is the very same way that spirograph patterns are made for laser-light shows. By using two rotating mirrors facing each other a short distance away, the laser bouncing off of one and onto the other. The two mirrors tilted at slightly different angles from perpendicular to their axis of rotation, One mirror for tighter circles the other for larger circles. When spun at different speeds will, when adjusted to the right speeds create those nifty mathematically perfect and complex curves. Even when not synced the spirigraph patterns will spin. These are fun to build, try making one after doing this speed-test. You can make your own laser-light show from a couple batteries, 2 small motors, a rheostat, a laser pointer, and 2 small bits of mirror in less than 30 minutes, from junk.]
Back behind the camera is set up a laser pointer, aiming in the general direction of where I'll be hand-holding the drill and rotating mirror. A piece of tape is used to hold the laser-pointer's switch closed.
Camera set to: ISO800, f/8.0, 1/3200 starting shutter speed, with high-speed bracketing set to 1/3EV increments to shorter and shorter durations.
Turn on drill, try to get the circle of light to evenly pass through the loupe and somehow fill most of the FOV of the camera (articulating LCD to the rescue in trying to align all this by hand). With the free hand press the shutter and take a sequence.
See this rough-layout diagram on how things are arranged.
NOTE: Due to the alignment of the laser, doing all this hand-held, do NOT misconstrue the brightness of the laser-arcs as shutter-speed differences. Length of the arcs should be the only factor here. Keep in mind too the varying width of the laser light as it laid-down its arc. Note the width of 1/6502 and 1/13004 compared to the others. The laser in those arcs traveling perpendicular to its width, in some others the laser traveling in the same orientation as its width. (Causing huge margin of error for measuring.) Also due to misalignment of the laser with the mirror, the loupe, and the wax-paper, some segments were brighter than others. For the curious, and those noticing the tapered exposure in some arcs, the light here was traveling in a counter-clockwise direction. The shutter was open at the beginning and closed slower at the end of each exposure.
I think, from looking at this, that it's safe to say that the S3 IS camera tops out around 1/40,000 of a second or so. There is the anomalous 1/20,000 (1/19,911) shutter speed that appears shorter, but I think that's due to discrepancies in how I held everything aligned when that particular frame was shot. The other shutter speeds afterward are decidedly shorter than the 1/26,000 and 1/32,000 ones. I included lines from the center in case anyone wants to measure the angular distance of each laser arc. I didn't bother to do that. The shutter-speeds listed by each sector were taken directly from the MakerNotes EXIF info where the override shutter speeds are recorded more accurately than Canon's generic values that only go as high as 1/3200.
In any case, a neat way to test shutter speeds!
(if adding new images, please place them above this section, and leave this one at the bottom, thanks)
Links to other interesting high-speed flash photography:[edit | edit source]
(in progress of hunting down some of the best, wanna help?)
- High-speed flash photography of water and milk drops, done in stereo-pairs.
- Camparison shots of falling milk-drops (just the drop, no neat splashes) using various flash units and power settings.
- These are mildly interesting but as with all images of hummingbirds taken in the last half-century with high speed flash to stop their motion they all look completely and totally fake and plastic. No amount of composition nor iridescent feather colors will save them from being worth only one quick glance. The photographer there might as well have used some museum's freeze-dried specimens and set up those birds and flowers in an indoor photo studio or used CGI (computer graphics) to generate those images. He even gives editing pointers on how to remove the fake looking catch-lights in their eyes caused by flash. Even that didn't save them from still looking 100% fake and worthless for decent nature photography. Here's where CHDK will finally come to the rescue. You'll be able to now stop a hummingbird's wings without the need of complex flash arrangements. You won't have to embed an artificial background to try to hide the pitch-black background caused by a half-century dependency on flash. At long last, the high shutter speeds now available with CHDK will make your stop-wing images of hummingbirds in flight look totally natural by using available sunlight alone. A typical setting for catching fairly sharp humming bird's wings in sunlight might be something like ISO 200, F 2.8, 1/8000.
- Wow, cool site. A page of about 100 high-speed photography. (And other specialty "Schlieren" photography, look it up, it's interesting stuff, I used to do this using old telescope mirrors.) An excellent resource to give you some ideas of subjects you might want to try with your new high-speed possibilities. Be sure to visit the author's homepage for even more ideas of specialty photography ideas. Here's a link to his text articles describing more detail on how these methods are used. (The site is a little confusing so this link will help get you to that page.)
- The holy grail of beverage photography is the ability to sync a flash at a high enough speed to stop the liquid, and beverage photographers have been using exotic and expensive lighting to achieve these results. Beverage photographers have traditionally used very high power strobes, dialed to the minimum power settings to create the shortest flash durations. I have rigged a Broncolor Mobil with a meatball delay to create flash photos at 1/8000 of a second.