Sony 4k camcorder with 1" sensor

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By ā€œlow end indie-filmā€ you mean gonzo porn?

Youā€™ll have to enlighten me, Rob.

From the specs: Imaging Sensor : 1" (13.2mm x 8.8mm) back-illuminated Exmor RĀ® CMOS Sensor

How do they get 1" from 13.2mm x 8.8mm? Do they add the two numbers? Itā€™s still not quite 1".
Itā€™s not a 3MOS sensor (from what Iā€™ve gleaned) so itā€™s not 13.2 x 8.8 x 3 = 348.48 ā‰  645.16 = 25.4 x 25.4.

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Itā€™s a 1" type, not actually 1": http://en.wikipedia.org/wiki/Image_sensor_format#Table_of_sensor_formats_and_sizes as well as http://www.dpreview.com/news/2002/10/7/sensorsizes

Still, I think the dirty secret among consumer-grade video devices is that regardless of the actual resolution, it says nothing for the quality of the actual video. I remember being excited when I got a Nikon D90, which could take 720p video. I did some test shots and yeah, I can shoot 720p video. But for it to look at all decent and not grainy and low-contrast, I need to have such an overwhelming amount of light that it only works outside on a sunny day or in an overwhelmingly-bright room (bright enough to shoot a movie in).

All I know is that 1" is smaller than APS-C, which is smaller than full frame, which is smaller than medium format, which is smaller than large format.
PS: 1inch is still smaller than [micro]-four thirds.

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Keep in mind those sensor sizes in the comparison graphic are for cameras, not video cameras. Video cameras are a very different best, even though movie capability is now coming in everything, itā€™s traditionally been a very different world. The number of megapixels in even a 4K video frame is very small compared to a modern DSLR or mirrorless camera. Approximately 8mp per frame in a 4K video, vs 16 and waaaay up for a digital photo out of a DSLR/mirrorless camera. The sensor size equation is very different for video. Sure, weā€™d all like to have a full-frame 4K movie-making monster of a camera, but those are made by Red, and have dragon-size prices to move that much data.

The image sensor size nomenclature for video cameras dates WAY back to the days of Vidicon tubes. The 1" refers to the diameter of the glass envelope that held the imager, not the size of the imager itself.

Thatā€™s why it seems like such a ripoff. It is.

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Seems pretty sweet but Iā€™m holding out a little longer.
The Sony sounds good and all but it records to XAVC-S or AVCHD.
HDMI out, so maybe thereā€™s an uncompressed 4:2:2 signal to grab?
But the only bit that really grabs my attention is the 120fps. That would be nice.

Some of the major motion picture film formatsā€¦ (very roughly)

8mm: 4.5 mm x 3.3 mm
Super8: 5.79mm x 4.01 mm

16 mm: 10.26mm x 7.49 mm
Super16: 12.52mm x 7.41 mm

35mm: 21.95mm x 18.66 mm
Super35: 24.89mm x 18.66 mm

Imax: (runs horizontally through the camera) 70mm*48.5mm

So technically, 35mm motion picture film is closer to APS than it is to ā€œfull frameā€, and 1 inch is sort of close to 16mm.

Imax is more ā€œmedium formatā€ territory.

I suppose it doesnā€™t much matter-- though the shallower depths of field associated with larger sensors can be annoying.

Thanks. Jeepers, like would it kill them to give useful information - say, the diagonal of the sensor?

35mm motion picture film, when first used in still photography, eventually was called ā€˜half-frameā€™. You can find some old ā€˜half-frameā€™ cameras out there, mostly Exactas and a Minox or two.

Conventional 35mm print negatives in still photography should have been called ā€˜double-frameā€™ but were called ā€˜full-frameā€™. Horizontally running 35mm movie film, which ends up using the same 24mm x 36mm frame as in conventional still photography, is called, logically enough, either VistaVision or Technirama.

Iā€™ll probably get this, as I adore my current Sony camera. Great sound and a great picture. And the zoom button makes a clicking sound which can be used to fool male cicadas into singing (and odd feature, but one I use).

What I really want is a consumer friendly priced slow-mo camera. Think a Phanom Flex camera in the $2K range.

http://edgertronic.com/ Not quite $2K, but getting closerā€¦

4k has been around for a while, just not at the consumer level. NHK showed it many many years ago and it is indeed gorgeous.

The problem is that 4k, like HD, will be compressed by the time you get it -more or less so depending on how you view it. Like HD it looks great coming off the camera but gets stomped on so much that a good deal of HD on cable is not that much better than NTSC.

The cable companies also compress more or less, depending on the content. The Super Bowl is compressed less than say the Spoiled Housewives of Whine County.

Iā€™m not saying 4K is a gimmick -on an appropriately large enough screen and even mildly compressed itā€™s pretty cool. Itā€™s just too bad most people wonā€™t ever see it in all itā€™s glory. Or even HD in full quality for that matter. Hint, set up a UHF antenna and compare the HD from your local stationā€™s over the air broadcast to the same image from the Evil Comcast.

How has click-bait title literalism already filtered down into product names?

ah it was an un-rememberable code number name too :frowning:

Comparisons to the D90 are unfortunate because that camera scales the picture by dropping pixels from the frame. It does not have enough processing power to do a full scaling that newer cameras do. So the camera wastes most of the light.

The sensor size has zero impact on the picture quality. It is the size of the lens that determines low light performance and depth of field. This type of camera is not going to be any use for shooting video with shallow depth of field in any case. You need to have a camera and lens setup that allows a second operator to work as the focus puller.

This camera is a bit pricey though. For $2000 I would want interchangeable lenses. something more like the Nikon 1 CX line (which has essentially the same sensor size).

Modern sensors deliver good enough response that a small lens is now more than sufficient for shooting in daylight even indoors. But there are times when you need more light and that means a bigger lens.

For the sake of easy math, imagine that the focal length multiplier is 2x. So a 50mm lens on this camera has an effective focal length of 100mm. Great, reach is good. But just as when you use a teleconverter, narrowing the field of view means you are throwing away light. Since a quarter of the light is thrown away you need a lens two stops faster to ensure the same amount of light falls on the sensor. Instead of an 100mm f/2.8, your 50mm needs to be an f/1.4. Both lenses have the same aperture though - 35mm.

Cameras are tools for measuring light, you want to measure in lower light, collect more of it.

Umā€¦ I donā€™t think thatā€™s quite correct. Have you tried using an external light meter?

Letā€™s say you use a point and shoot camera with a crop factor of 6 (I think thatā€™s about 1/2.5"). Any way, to get a equivalent field of view of a 35mm normal lens, the camera uses a 6mm lens.

Now, letā€™s imagine taking a picture of an object 3 meters away at f2 with a Canon 5DMarkIII using those two lenses: a 35 mm normal, and a 6mm fisheyeā€¦
According to [Depth of Field Master][1], the respective depths of field
are
6 mm: 0.5 m-- Infinity
35mm: 2.62 m ā€“ 3.51 m

Fisheye lenses are notoriously easy to focusā€¦
[1]: Online Depth of Field Calculator

Put that 6mm lens on your P&S camera, and sure, youā€™ll have the same field of view as your full-rame camera, but nearly everything will be in focus, including any distracting background. A large sensor lets you use depth of field for artistic effects.

Besides, f/1.4 lets in twice as much light as f/2.0, and four times as much as f/2.8.

ISO is (at least theoretically) calibrated so that two cameras can be set to the same aperture, shutter speed, and ā€œfilmā€ speed, and produce images that are identically exposed. However, that does not mean that both images will be absolutely identical-- a Nikon Df set to ISO 6400 will produce a image that is considerably less grainy than a Nikon D3100 set to Hi1.

Thatā€™s why the Df is so intriguingā€“it can be used in exceptionally low light, yet still produce a clean, detailed image.

You donā€™t seem to understand the difference between depth of field and exposure. I was talking about the light which only depends on the field of view and the aperture of the lens. The same amount of light will fall on a 1x1" sensor placed 1" from the focal node as a 2"x2" sensor twice the distance away and so on. Sensor size is irrelevant.

If you double the aperture you increase the amount of light by two stops, not one because the area of the lens goes with the square of the aperture. Doubling the aperture means four times the light.

Halving the linear sensor dimensions means limiting the field of view to a quarter. Which for long focal lengths is roughly equivalent to doubling it.

You also seem to be confusing a 35mm aperture for a 35mm focal length. By convention aperture is usually given as a ration of the focal length. But since we are talking about the actual dimensions of the lens what matters is the width. This is at least as wide as the aperture. Though for wide angle SLRs the lens has to be a retrofocus design and the lens has to be a LOT wider than the aperture. My 14-24 f/2.8 has an aperture of 5-9mm but it is more than ten times the size.

A 6mm lens is only a fisheye lens if it is designed in a particular way. Nikon sell a 10.5mm fish eye and a 10-24mm rectilinear DX zoom. Again what matters is the field of view and the aperture. The sensor size only affects the depth of field if you expand the series in the optical equation to the third term.

The depth of field gets narrower as the field of view gets narrower. Which is hardly surprising. If you zoom in you are in effect magnifying the inaccuracies in the focus. Those actually originate from the fact that the lens is not a point. A pinhole camera has infinite depth of field (but suffers from diffraction). A 35mm aperture gives almost the same depth of field for a given angle of view.

Using depth of field calculators to compare camera design choices requires quite a bit of care because more factors change than most of the calculators know. The circle of confusion size that is relevant changes for instance.

The relevant comparison here is not how a 6mm focal length lens and a 35mm focal length lens. We know that putting a smaller sensor in a camera designed for a larger one gives sub-par results. The issue here is how the size of the sensor affects the performance of a camera designed around it. And it really does not unless the number of pixels gets very large.

Itā€™s incredible just how wrong this is. Sensor size matters. the size of the photosites (i.e., pixels) matters. Lens ā€œsizeā€ (whatever that is supposed to mean) is not the sole determinant of either depth of field or light-gathering ability. Depth of field depends on the combination of aperture, focal length, sensor/film size, output size, and viewing distance (for the purposes of video we can ignore output size and viewing distances since all video cameras are going to be used on the same displays viewed at the same size).

You clearly have no idea how lenses work. An f/2.8 lens is an f/2.8 lens. If something requires a 1/1000 shutter speed with a 100mm lens at f/2.8, it will also require the same shutter speed with a 50mm at f/2.8. It doesnā€™t matter if the film/sensor is a different size or not. I mean, just say something is properly exposed on 35mm film. If you suddenly cut that film down to APS size, is this same film suddenly exposed wrongly? Itā€™s not different with a sensor.

What the hell is this supposed to mean? The same amount of light falls on a 1"x1" sensor from 1" as does on a 2"x2" sensor from 2"? Huh?

If the lenses have the same aperture, and youā€™re talking about light per square inch, then this is by definition true.
Assuming that both lenses are focuses at infinity, then the focal length of the first lens is, by definition, 1" or about 25mm. This would make the focal length of the second lens 2", or about 50mm. If both lenses are set to the same aperture, such as f/2.0, both will let the same amount of light per unit area onto their respective sensors: both will produce the same exposure. Yes, the 2"x2" sensor has a larger area, but the 50mm lens has an optically larger aperture (25mm at f/2.0) compared to the 25mm lens (12.5mm at f/2.0), which is why the exposure is the same: even though the 2"x2" sensor is four times larger than the 1"x1" sensor, the larger aperture of the 50mm/2.0 lets in four times as much light to cover it. There is thus no need to change aperture to get the same exposure, because f-stops are designed to be constant between focal lengths and sensor sizes.