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Hadi Sapre

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Aug 4, 2024, 6:59:32 PM8/4/24
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Onmy ArduPilot quad-copters that carry Sony alpha series cameras like a Sony a6100, I operate at a much higher speed. This camera can store each image in less than a second. I operate at speeds where the interval between images is usually 0.8 seconds. At 50 meters altitude, this works out to about 7 to 8 meters per second.

Pix4D maintains a massive rolling shutter readout database, which might be why it appears they determine it from analysis, but as far as I am aware, they do not derive readout from the data experimentally.


Has anyone applied pauses for photos? I think I read that a 1/10-1/5 second pause for a photo suffices to rid the rolling shutter problem. Can a drone really stop that fast, stop wobbling, then take a photo while the camera is not moving?


Exactly. I typically use the ArduPilot Mission Planner program - which calculates a minimum shutter speed for the altitude and ground speed. I use shutter priority and set the shutter speed accordingly. At high meters per second speed and low altitude this can be 1/1600 or faster.


It looks like you are running a time lapse with 100 ms intervals, but only 30ms exposures. The MM Acquisition engine will close the shutter in between exposures to prevent photo-damage. If you really want to continuously expose your sample, you can uncheck the autoshutter checkbox in the main window and open the shutter manually. Alternatively, you can increase your exposure time to be the same as your interval (set exposure to 100 ms, interval to 0 ms), and your camera will acquire data as fast as it can (with 100 ms exposures). If you do so, you may want to reduce the light intensity.


I was under the impression that keeping the option unchecked would result in the shutter closing in between exposures, while keeping the option checked would override this. In either case, the option checked or unchecked result in the same acquisition, which is what confused me. Also, I had set the interval to 0 ms (and also changing the exposure to shorter or longer) and the shutter still opens and closes in between shots with the option checked.


What happens for multi-channel acquisitions where there are 2 different shutters? The microscope has a shutter for bright-field and a different shutter for fluorescence. I am not worried about photo-damage from the bright-field lamp, but am worried for the fluorescence lamp. I would want the bright-field shutter open while imaging in bright-field as fast as possible, but for fluorescence I would want the typical behavior of closing the shutter in between exposures. What settings could I change to do this? I am worried that unchecking the autoshutter would result in both shutters being always open.


However, I am not sure why you still see the shutter opening and closing when you only select Time Points and the interval is lower than the exposure time. That should result in a sequence acquisition where the shutter stays open.


The issue now is sustaining a fast frame rate. For frame rates >200 fps, how can I ensure a sustained frame rate? I have noticed that the DeltaT parameter stored in the tif stack xml is not a series of constant increasing values, but rather a series of monotonic, repeating values.


I made the photograph at the top of this post during our recent redwoods workshop, as big waves crashed against a rocky shore. We were happy to see those large swells, as seas in this area are typically rather placid in June.


I made many exposures with fast shutter speeds, freezing the spray of some big wave splashes. But late in the afternoon the hazy/misty atmosphere grew thicker, softening the light, and creating beautiful pastel colors. I remarked to our group that it looked rather painterly.


So I stuck with one second, and fired off frame after frame as waves splashed and receded. Some of the best moments with that one-second shutter speed came when a wave poured off a rock, creating a waterfall effect. The photograph above actually has both a splashing wave (in the distance) and a receding wave (in the foreground) in the same frame.


I started off using very-slow shutter speeds (10 to 30 seconds) to blur the motion of not just the water, but the streaming fog. Then the sun rose higher and started to break through the fog and light the breaking waves.


When you see an opportunity to make an expressive photograph, you want to use every tool at your disposal to enhance its message. Those tools always include light, composition, and the moment you capture, but sometimes camera controls can also play key roles. If something in the frame is moving, think about how you can use the shutter speed to control not just how that object looks, but how its appearance affects the story and mood of the image.


Michael Frye is a professional photographer specializing in landscapes and nature. He lives near Yosemite National Park in California, but travels extensively to photograph natural landscapes in the American West and throughout the world.


Great piece. It starts out with some basic principles (reminders for many) and then you explain the multiple approaches can create. Good piece for beginners thru more advanced photographers who know the skills and are encouraged to think about a variety of approaches


ISO 400, f/22, 0.4 second. The shutter speed here was a little longer than I wanted. I needed a faster speed to stop the trillium from blowing in the wind, but I needed f/22 for maximum depth of field (there still isn;t enough DOF to render the distant trees sharp). I shot this many years ago. In hindsight, I should have raised the ISO to increase the shutter speed.


I shoot full manual 98% of the time. Recently, whenever I set up a shot (for example, f/2.8, 1/500th, ISO 320) I will press the shutter half way to focus and the camera will revert my shutter speed to 1/180th of a second and not let me shoot any faster. I do not have any sort of external flash set up - there's nothing in the hotshoe at all. I've checked all my settings and can't quite figure out why it won't let me shoot over 1/180th. I have a wedding to shoot tomorrow and I'm getting really frustrated. Any help is appreciated!!


I've been having a problem recently with the R6. On occasion, I press the shutter button to take a photo and the shutter fails to work. It has failed when using AF and also using MF. It's failed with my Canon 100-400mm and with my Tamron wide-angle. Turning the camera off and back on usually fixes the problem for a while but the problem eventually recurs. Removing the battery and reinserting them works temporarily.


I'm using the current firmware. In fact, I upgraded to that firmware a week or so before the problem started. Canon customer service suggested I clear all the custom functions. Problem with that is I want to use those functions.


kvbarkley's suggestion is about all you can do. I suspect that Canon may not take the camera for repair until you do what they suggested. Even if they do, they will reset it themselves, so you'll loose those settings anyway.


The shutter controller accepts a TTL signal with a max voltage of 42V. Currently it is hooked up to a digital port on the NI USB-6009, and I have been able to manually controll the shutter throught the NI USB-6009 software.


The USB-6009 is a relatively new device, and LabVIEW 8.5.1 is rather old software. You need to check to be sure that you have drivers (DAQmx) for your version of LabVIEW that support this hardware. It sounds as if you have it set up in MAX and are controlling the output manually, which is a good sign. I don't have access to version 8.5.1 and I don't remember exactly what features it supported, but the attached picture shows a simple block diagram in a new version of LabVIEW that would do what you want. Of course you should test it with shorter times and fewer iterations because this one takes more than 2 weeks to complete! Add any controls, indicators and error-checking that you want.


Thank you! This is exactly what I was looking for. I modified your design slightly, including the DAQ assistant at the beginning. I also changed the constants to variables so I can adjust to timing and number of cycles as needed.


Here is a great example of when to turn off the electronic shutter and switch to mechanical. I was shooting a music festival this weekend and the drummer in this one band was off the chain. He was really good, tight, and fast. I walked around back-stage so I could get closer to him with the FE24mm f/1.4GM and my new a7CII camera. I had been shooting all day on electronic shutter but then I previewed a few frames that I had just shot and noticed the drum sticks were really distorted. As they are made of wood and not rubber, I quickly changed over the mechanical shutter and kept going. Once I finished those images, I switched back to silent shutter just to conserve my battery. I shot from 8a through to 6:15pm on one battery and also did four video interviews in 4K!


To your point, Alex, you are 100% right in terms of making noise while shooting. The other side of the coin though, is battery life and when you use electronic shutter the cameras sip rather and drink. The three cameras that make up the a7C series are the most battery efficient of all of the Alpha lineup.


Background - I don't use a flash, and I had been wandering around with the FE 24-105mm F4 G OSS, taking candid shots with the silent shutter. Everybody was fine with that, but my sister was not alone when it came to hearing the shutter for group shots. Mind you, I got some of the best shots just after I had taken one, thanked folks, everyone relaxed, and I grabbed a few more.


Wow! I had no idea the impact and difference with mechanical vs silent.... O_O hmmm... I wonder how many missed opportunities would have been easy fixes... The mechanical shutter is so noisy though... I've been pretty much shooting permanently electronic shutter when doing wildlife, I would up the shutter speed.


Universe is here for the makers, the doers, the people who dream in colors. You bring your curiosity and ideas, we'll provide the knowledge, the inspiration, and the state-of-the-art imaging tech to help you make dreams reality.

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