An exercise in photographic futility?
It’s happened to all of us. You’re out and about shooting video and an unexpected opportunity for a great still suddenly presents itself. Your camera is stashed away in your bag, but you remember that your camcorder has a photo mode. You flick a switch and snap off a half dozen frames, happy that the shot opp didn’t slip away. But later that night, as you review the day’s haul, you come across the stills and find that they’re noisy, poorly lit and badly coloured. You shake your head, switch off the monitor, and wonder where it’s written that all stills taken with video cameras have to suck.
You could blame a variety of things. For starters, camcorders typically don’t provide controls for settings like shutter speed and aperture. Then there’s the hard fact that their processors are generally geared for rendering video, not touching up stills. But while these and other issues bear significant weight, the biggest problem is that camcorder image sensors just don’t capture as much visual information as the sensors inside most digital cameras.
Quick word on image sensors: They’re made up of thousands or millions of tiny photodiodes that capture light. Assuming a shot is captured at the image sensor’s maximum resolution and undergoes no compression, each pixel in the final image represents the light captured by a single photodiode. (Hence, a sensor with five million photodiodes is capable of generating a five megapixel picture.)
The problem with consumer camcorders is that their image sensors typically have far fewer photodiodes than those of digital cameras. Lower end models can have less than half a million, while expensive high-definition models max out at around three million. But wait, you say, my camcorder can take pictures at resolutions of four, five or even six megapixels. The math doesn’t add up.
According to Panasonic Canada’s Dan Kesselring, the incongruity occurs because camcorders often turn one pixel into multiple pixels. “Pixels on a still camera image sensor are basically small and square,” explains Kesselring, “while pixels on a camcorder image sensor are more rectangular and typically much larger. By dividing or shifting individual pixels on a camcorder image sensor we can create more pixels. It’s pretty standard within the industry.”
The upshot is that while your five or six megapixel camcorder photograph might have a few million more dots than the image sensor that captured it, there’s not really any additional image data in the picture. The pixels have just been divvied up a bit.
The moral? “Always take a still camera with you,” says Kesselring. “A camcorder’s camera function can come in handy sometimes, but it just hasn’t reached a point yet where it can replace a digital camera.”
Not that we don’t trust Mr. Kesselring, but we decided to see for ourselves. We test drove three camcorders that have received critical praise for their video quality with an eye to evaluate their photography functionality. Given what we’ve learned about how video cameras capture stills, the results of two of the models we looked at were predictable, but we were modestly surprised by the third.
Canon DC22 ($549) http://www.canon.ca/
This entry level DVD camcorder from Canon has relatively straightforward still photography functionality. You can’t capture pictures while recording video, and image setting options are rudimentary. Just flip from video to camera mode and press the photo button to take 2 megapixel stills. No fuss, no muss. How do the shots look? Let’s just say you probably wouldn’t want to spend the two bits it would cost to print them. The only legitimate situation to use the DC22’s still image mode is if you happen to catch a glimpse of a Sasquatch and haven’t time to pull out your camera - the resulting grainy, off-colour picture will fit right in with all the other photos ever taken of the mythical beast.
Panasonic SDR-H200($1,099) http://www.panasonic.ca/
Panasonic’s premier hard disk camcorder employs a 3CCD system, which basically means it uses three separate sensors to record each of the three primary colours. The difference in video quality can be significant, but it doesn’t really have an impact on stills. Each sensor is made up of about 700,000 pixels, for a combined resolution of 2.1 megapixels, but Panasonic splits these pixels to deliver photos up to 3.1 megapixels. Image quality surpassed the DC22, but not by much; some shots had more authentic colouration and a bit less noise, but they still wouldn’t pass for pictures captured by a dedicated digital camera.
Sony HDR-HC7 ($1,499) http://www.sonystyle.ca/
Hands down one of the best consumer camcorders on the market, Sony’s high-definition, Mini DV HDR-HC7 has a video image sensor with a whopping 3.2 million pixels from which it can generate stills up to 6.1 megapixels in size. However, while test shots showed a clear advantage in image clarity and resolution, the lighting was still on the dark side—even in bright outdoor settings. Still, the HDR-HC7’s photos were easily the best of the bunch, and might even be capable of going head-to-head against shots captured with an entry-level digital camera.
It’s happened to all of us. You’re out and about shooting video and an unexpected opportunity for a great still suddenly presents itself. Your camera is stashed away in your bag, but you remember that your camcorder has a photo mode. You flick a switch and snap off a half dozen frames, happy that the shot opp didn’t slip away. But later that night, as you review the day’s haul, you come across the stills and find that they’re noisy, poorly lit and badly coloured. You shake your head, switch off the monitor, and wonder where it’s written that all stills taken with video cameras have to suck.
You could blame a variety of things. For starters, camcorders typically don’t provide controls for settings like shutter speed and aperture. Then there’s the hard fact that their processors are generally geared for rendering video, not touching up stills. But while these and other issues bear significant weight, the biggest problem is that camcorder image sensors just don’t capture as much visual information as the sensors inside most digital cameras.
Quick word on image sensors: They’re made up of thousands or millions of tiny photodiodes that capture light. Assuming a shot is captured at the image sensor’s maximum resolution and undergoes no compression, each pixel in the final image represents the light captured by a single photodiode. (Hence, a sensor with five million photodiodes is capable of generating a five megapixel picture.)
The problem with consumer camcorders is that their image sensors typically have far fewer photodiodes than those of digital cameras. Lower end models can have less than half a million, while expensive high-definition models max out at around three million. But wait, you say, my camcorder can take pictures at resolutions of four, five or even six megapixels. The math doesn’t add up.
According to Panasonic Canada’s Dan Kesselring, the incongruity occurs because camcorders often turn one pixel into multiple pixels. “Pixels on a still camera image sensor are basically small and square,” explains Kesselring, “while pixels on a camcorder image sensor are more rectangular and typically much larger. By dividing or shifting individual pixels on a camcorder image sensor we can create more pixels. It’s pretty standard within the industry.”
The upshot is that while your five or six megapixel camcorder photograph might have a few million more dots than the image sensor that captured it, there’s not really any additional image data in the picture. The pixels have just been divvied up a bit.
The moral? “Always take a still camera with you,” says Kesselring. “A camcorder’s camera function can come in handy sometimes, but it just hasn’t reached a point yet where it can replace a digital camera.”
Not that we don’t trust Mr. Kesselring, but we decided to see for ourselves. We test drove three camcorders that have received critical praise for their video quality with an eye to evaluate their photography functionality. Given what we’ve learned about how video cameras capture stills, the results of two of the models we looked at were predictable, but we were modestly surprised by the third.
Canon DC22 ($549) http://www.canon.ca/
This entry level DVD camcorder from Canon has relatively straightforward still photography functionality. You can’t capture pictures while recording video, and image setting options are rudimentary. Just flip from video to camera mode and press the photo button to take 2 megapixel stills. No fuss, no muss. How do the shots look? Let’s just say you probably wouldn’t want to spend the two bits it would cost to print them. The only legitimate situation to use the DC22’s still image mode is if you happen to catch a glimpse of a Sasquatch and haven’t time to pull out your camera - the resulting grainy, off-colour picture will fit right in with all the other photos ever taken of the mythical beast.
Panasonic SDR-H200($1,099) http://www.panasonic.ca/
Panasonic’s premier hard disk camcorder employs a 3CCD system, which basically means it uses three separate sensors to record each of the three primary colours. The difference in video quality can be significant, but it doesn’t really have an impact on stills. Each sensor is made up of about 700,000 pixels, for a combined resolution of 2.1 megapixels, but Panasonic splits these pixels to deliver photos up to 3.1 megapixels. Image quality surpassed the DC22, but not by much; some shots had more authentic colouration and a bit less noise, but they still wouldn’t pass for pictures captured by a dedicated digital camera.
Sony HDR-HC7 ($1,499) http://www.sonystyle.ca/
Hands down one of the best consumer camcorders on the market, Sony’s high-definition, Mini DV HDR-HC7 has a video image sensor with a whopping 3.2 million pixels from which it can generate stills up to 6.1 megapixels in size. However, while test shots showed a clear advantage in image clarity and resolution, the lighting was still on the dark side—even in bright outdoor settings. Still, the HDR-HC7’s photos were easily the best of the bunch, and might even be capable of going head-to-head against shots captured with an entry-level digital camera.
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