sports video camera zoom image
Gladiator
I have often wondered why a digital/Hard drive/flash drive/etc. video camera can sport up to a 50x optical zoom, whereas the largest digital photo camera zoom i have seen (excluding humongous, extremely expensive SLR zoom lenses) is 20x on an Olympus. Is it too hard to get a high-quality 50x zoom onto a camera, or what?
Answer
There is nothing to guess about. There are two reasons for this.
First, the sensor size. Because most video cameras, regardless of what kind, don't capture video in 6, 8 or 10 megapixels they way a still camera will, the sensor can be smaller.
When the sensor gets smaller, it's easier to get that extra zoom because of a crop factor.
Next, would be size. Along with a tiny sensor, video cameras are generally larger than digital point and shoots. With that larger and deeper size, three is room for a larger lens.
There is nothing stopping you from getting 50x from a digital point and shoot. But the sensor size might have to drop, and it might be a lower resolution, like 2 or 4 megapixels for example. Next, you'll have a huge lens to deal with.
As sensor size increases, like say in a digital SLR, there is no way to get around the fact that you need a huge lens just to match the reach of a decent compact digital zoom. So the bottom line, it's a law of physics that stops you from getting a monster zoom on a tiny camera, it's not because camera companies don't want to do it.
There is nothing to guess about. There are two reasons for this.
First, the sensor size. Because most video cameras, regardless of what kind, don't capture video in 6, 8 or 10 megapixels they way a still camera will, the sensor can be smaller.
When the sensor gets smaller, it's easier to get that extra zoom because of a crop factor.
Next, would be size. Along with a tiny sensor, video cameras are generally larger than digital point and shoots. With that larger and deeper size, three is room for a larger lens.
There is nothing stopping you from getting 50x from a digital point and shoot. But the sensor size might have to drop, and it might be a lower resolution, like 2 or 4 megapixels for example. Next, you'll have a huge lens to deal with.
As sensor size increases, like say in a digital SLR, there is no way to get around the fact that you need a huge lens just to match the reach of a decent compact digital zoom. So the bottom line, it's a law of physics that stops you from getting a monster zoom on a tiny camera, it's not because camera companies don't want to do it.
Are videos on the Canon SX10 as good as the one on the Canon FS100 video camera?
jhoo828
I need a nice (not HD) video camera. I decided that an SD-based Canon FS100 would at least be close to the image quality on my old Sony TRV250 Hi-8 camcorder. Rather than pay for the FS100 alone, would the video quality on a new Canon SX10IS be about the same as well as giving me a nice still cam?
Answer
You can't quite get both in a single model, yet.
By spec, the Canon's movie mode is decent enough... it's recording at 640x480, which is a "square pixel" version of the standard 720x480 that pretty much all NTSC SD camcorders use... slighly lower pixel count, but it's not a huge issue. Canon still recording tends to be in same ballpark as lower cost video camera video... I have not used this particular model, but in general, I can state this. 30fps will be a bit more "movie like" than the 60i (interlaced) you would get with regular video. If you're making DVDs, you might notice this, particularly with sports and other fast moving things. If your goal is computer video, the non-interlaced video from the SX100 might actually be preferable (I don't know if the FS100 has a progressive mode... most of Canon's HD models do today).
So look at compression.. the SX10 can record 1 hr. 30 min on an 8GB flash card, while the FS100 at top quality can record 1hr. 50min.. That sounds like the SX10 is actually using less compression, but we have to check the format. The FS100 records in MPEG-2, as used on all DVDs. At that bitrate, the FS100 is slightly better than DVD quality.
Checking into the SX10, I find that, like most digital still cameras, the SX10 uses Motion-JPEG for video, which is very similar to the DV format. To DV and MJPEG are simpler compression schemes than MPEG-2, so you need more bits per second to get the same quality. DV camcorders use 25Mb/s, while the SX10 is recording around 11Mb/s here. So I would expect this video to be relatively low quality, compared to DVD or the FS100, at least in terms of digital noise (artifacts and other ugly bits due to compression). It might still look fine, but it's probably more like one of the FS100 "long play" modes rather than top quality.
Next is sound.. most digital still cameras have pretty evil microphones, in mono, and no way to add an external one. The SX10 is a bit better than this.. you can't add a mic, but at least it's recording in stereo. Also, the mics are apparently just above the lens housing, and thus less probe to being blocked by your hands (a real problem with many still cameras used for video).
Then there's "features while recording". Traditionally, most digital still cameras with video recording were not good camcorders, even given their limitations, because some features didn't work during recording. The first one I had with this mode, a Canon from the 90s, didn't even keep the viewscreen active. It's more common for autofocus, autoexposure, and/or zoom to not function while doing video. Some do it.. I have a Panasonic TZ5 which does keep everything active during video, and functions as a somewhat reasonable camcorder (with bad sound and too-high compression, but I have used it as a third video camera on shoots from time to time). So I looked it up, and while it's not easy to find, one review (included below) did find that auto-focus/exposure remain active during video, and you can zoom. In general, this camera is better designed for video than most.. for example, there's a separate video button which can be used in any photo mode -- most DSCs make you switch to a different "movie mode", which is a bit annoying (my Panny is like this).
So yeah, I would bet that the SX10 would deliver video comparable to the TRV250, if not quite on par with the FS100. And naturally, the stills will be dramatically better than using the FS100 as a still camera. You are limited to 4GB file sizes, which means you get about 40 minutes at top quality before you have to stop shooting, but you can start again right away if you have an 8GB memory card (my Panasonic is the same way... it's because they use the FAT32 file system on the SD card, which is limited to 4GB maximum). With some limitations, it's going to be decent for casual video use, much better at least than most digital still cameras.
You can't quite get both in a single model, yet.
By spec, the Canon's movie mode is decent enough... it's recording at 640x480, which is a "square pixel" version of the standard 720x480 that pretty much all NTSC SD camcorders use... slighly lower pixel count, but it's not a huge issue. Canon still recording tends to be in same ballpark as lower cost video camera video... I have not used this particular model, but in general, I can state this. 30fps will be a bit more "movie like" than the 60i (interlaced) you would get with regular video. If you're making DVDs, you might notice this, particularly with sports and other fast moving things. If your goal is computer video, the non-interlaced video from the SX100 might actually be preferable (I don't know if the FS100 has a progressive mode... most of Canon's HD models do today).
So look at compression.. the SX10 can record 1 hr. 30 min on an 8GB flash card, while the FS100 at top quality can record 1hr. 50min.. That sounds like the SX10 is actually using less compression, but we have to check the format. The FS100 records in MPEG-2, as used on all DVDs. At that bitrate, the FS100 is slightly better than DVD quality.
Checking into the SX10, I find that, like most digital still cameras, the SX10 uses Motion-JPEG for video, which is very similar to the DV format. To DV and MJPEG are simpler compression schemes than MPEG-2, so you need more bits per second to get the same quality. DV camcorders use 25Mb/s, while the SX10 is recording around 11Mb/s here. So I would expect this video to be relatively low quality, compared to DVD or the FS100, at least in terms of digital noise (artifacts and other ugly bits due to compression). It might still look fine, but it's probably more like one of the FS100 "long play" modes rather than top quality.
Next is sound.. most digital still cameras have pretty evil microphones, in mono, and no way to add an external one. The SX10 is a bit better than this.. you can't add a mic, but at least it's recording in stereo. Also, the mics are apparently just above the lens housing, and thus less probe to being blocked by your hands (a real problem with many still cameras used for video).
Then there's "features while recording". Traditionally, most digital still cameras with video recording were not good camcorders, even given their limitations, because some features didn't work during recording. The first one I had with this mode, a Canon from the 90s, didn't even keep the viewscreen active. It's more common for autofocus, autoexposure, and/or zoom to not function while doing video. Some do it.. I have a Panasonic TZ5 which does keep everything active during video, and functions as a somewhat reasonable camcorder (with bad sound and too-high compression, but I have used it as a third video camera on shoots from time to time). So I looked it up, and while it's not easy to find, one review (included below) did find that auto-focus/exposure remain active during video, and you can zoom. In general, this camera is better designed for video than most.. for example, there's a separate video button which can be used in any photo mode -- most DSCs make you switch to a different "movie mode", which is a bit annoying (my Panny is like this).
So yeah, I would bet that the SX10 would deliver video comparable to the TRV250, if not quite on par with the FS100. And naturally, the stills will be dramatically better than using the FS100 as a still camera. You are limited to 4GB file sizes, which means you get about 40 minutes at top quality before you have to stop shooting, but you can start again right away if you have an 8GB memory card (my Panasonic is the same way... it's because they use the FAT32 file system on the SD card, which is limited to 4GB maximum). With some limitations, it's going to be decent for casual video use, much better at least than most digital still cameras.
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