74

A picture is worth a thousand words, here. This is a Twin Lens Reflex camera: The two lenses are linked together so they focus as a set (either the whole front panel moves, or the lenses are linked by gears so that they turn together to focus). The top lens — the "viewing lens" — has a mirror which bounces the view to the ground-glass viewfinder. The bottom ...


54

Single lens means that there is only one lens attached to the camera at once. This is to distinguish it from a twin-lens reflex camera, which has two lenses - one used for the viewfinder and one used for actually taking the photo.


40

If I have built my device with the correct distance between the flange and the optical plane, does this mean the (inexpensive) lens I am using is bad? If you had built your device using the proper specified flange distance of 17.526mm instead of rounding it off to 18mm you probably would not be asking this question. 0.474mm doesn't seem like much, but it ...


28

In actuality, a cross type AF sensor is just two "normal" AF sensors, one with the lines oriented in a vertical direction and the other with the lines oriented in a horizontal direction, that are superimposed over the same area. Non cross-type AF sensors can be either vertical, horizontal, or even diagonal. Some very early AF film cameras with a single ...


25

Shutters are probably more accurate/reliable now, but more importantly with digital photography you get instant feedback so you can tell right away if there are any exposure problems, you're not going to ruin several rolls of film before you find out. I had a 1DsII that had a shutter which suddenly became unreliable at anything faster than 1/500s, I ...


25

The main reason is that it is low powered. An raster LCD - color or not - requires much more power and most of them need a permanently on back-light. New OLED display do not need the back-light but still pull more power than a segment-based LCD which has much fewer electronic circuits. Most current top-plate LCDs mirror what is shown in the status line of ...


23

As was said, the mechanical shutter has speed limitations. As to the slit, try to imagine without it. Suppose the shutter opens by moving from top to bottom of frame. And then of course, it has to close from bottom to top. So it is open longer on the top side than on the bottom side, which is uneven exposure. Modern fast curtains might move about 7 ...


22

Weather Sealing is protection of the internal parts of a camera from external influences such as moisture, dust, and humidity. The degree of this weather sealing varies between manufacturers and also within models by each manufacturer. The protection is provided by both rubber sealing with silicon rings and gaskets as well as design considerations such as ...


22

There isn't. Once you have the basics needed to make a digital camera work, the incremental cost of additional features is very small, so there is a very strong incentive to cover at least the most common and popular features people expect — and a lot of competitive pressure. Even "retro" cameras like the Nikon Df have all the bells and whistles inside. (...


21

Phase detect autofocus in DSLRs works by comparing patterns of light coming from each side of the lens using pairs of detectors which are separated a certain distance on the AF sensor. This distance is called the baseline, and the greater the baseline the more accurately the distance can be measured. The need for a wide baseline and for light to travel from ...


21

Thought experiment time. Assume we'd like a minimum exposure of 1/2000 of a second (500 microseconds) on a 35mm full frame camera. We have a single 'shutter' to move out of the way, and back. We'll tolerate one side of the picture being 10% more exposed than the other, so that means we allow 50μs to move the shutter back and forth. So the shutter has to ...


18

It's important to realize that you don't actually look directly through the lens with an SLR! If you did, a periscope style arrangement would do just fine. What you are actually doing is looking at an image projected onto the focussing screen by the lens. This image is flipped left/right and up/down by the lens, and then up/down again by the main mirror. ...


18

Hitting the DOF preview with a stopped down aperture should make it obvious: what you see can be very dim, dim enough it can be very difficult to compose and focus. That's why cameras have the lens wide open until actually taking a picture, so you can get the brightest image by which to setup your shot.


17

Magnesium alloy is one of the most preferred material used in DSLR Bodies, Laptops and other Gadgets. It is a mixture of Magnesium and alloy which is often aluminum, zinc, copper, silicon, zirconium and other minerals, and to answer your question why not aluminum? Well, not only aluminum but a combination of the said minerals. This mineral is also used in ...


16

if I use the auto-focus, does it adjust the lens focus, or is there a secondary lens in the body that gets adjusted? No, there's no secondary lens. The lens attached to the camera contains a motor that moves the lens elements as required by the autofocus system. Same with the aperture settings, is this changing on the attached lens, or is there another ...


14

Pros of using an EVF as opposed to the rear LCD screen: It is easier to see in direct sunlight. Holding the camera to the eye increases stability and comfort (especially with heavier lenses). EVFs offers diopter correction so users don't need to wear eyeglasses.


14

The biggest functional difference between a leaf shutter and a focal plane shutter is the ability of a focal plane shutter to precisely allow the same amount of exposure time for the entire field of light collected at the front of the lens and to allow the practical use of faster shutter speeds. Due to the fact that leaf shutters are open in the center ...


14

Andrea at SAR has plenty of contacts within Sony. They wont listen to you though. Large companies have extensive procedures and policies relating to design which is why it takes so long and the results are such a mess. Your best bet would be via some up and coming camera manufacturer like Blackmagic, or do it yourself (or by partnering with a developer) by ...


13

I expect that a company gets attempts like this every day. And most of them are totally useless crazy ideas. Your idea very well may be the exception, but odds are — speaking impersonally — it's not. That's why the system which makes it difficult to speak to anyone exists. It is protection. Additionally, if the idea is as great and inevitable as you suggest,...


13

Why do we need a DOF preview button? So that you can see how much depth of field you'll get when the shot is actually taken. Why not just show the effective depth of field, by default? Because your eyeballs don't have variable shutter speed or auto ISO. And because autofocus systems need plenty of light to work well. Try setting your camera to f/22, ...


12

The Bayer filter passbands are designed to be make the sensor have a reasonable match to the human eye, while not costing too much. They're fairly leaky even in the visible part of their stop band, and pretty much uncontrolled in the IR. To increase their blocking in the IR a more expensive recipe in a thicker layer would be needed. The thicker layer isn't ...


12

You definitely have to change the design of the camera. This HowStuffWorks page explains how instant film develops well enough. Essentially, the film cassette contains rollers that roll out the developer to begin developing your film. Until this happens, the film is still light sensitive. This is why the cassette begins with a plastic, light blocking layer ...


10

Just a guess, but I don't believe that ND filters are so widely used as you assume. A very large share of the users of a specific camera will never need an ND filter and therefore not be interested in paying whatever extra it will cost to include the filter in the camera. To make sense, an embedded ND filter would also have to be variable, otherwise it ...


9

The more important letter in DSLR is the R, which stands for reflex. What differentiates reflex cameras from others is that the image is made to appear on a screen that's positioned in a way that's optically-similar to the film plane for composition and focusing. (View cameras work the same way, but the screen is the film plane.) Early designs had two ...


9

If not, do I move the lens away or closer to the optical plane to fix the problem? If the lens will focus on near subjects, but not on a subject at "infinity," then that means that the lens is too far from the sensor. You need to move it closer.


8

Russell, large companies like Sony do not work the way as you would expect. They have executive planning, and they usually respond to already existing needs gathered from the field. The larger a company and the more shareholders are there, the more conservative approach they take. So your options are: You patent, you create a prototype, you create a ...


8

Segment LCD is a technology with the lowest power consumption of all available display technologies and those are more than visible on sunlight or any kind of strong light without any need for background lightning (except at night). Very useful for battery operated devices. It's also the cheapest possible display technology. They are also extremely robust. ...


8

As Caleb pointed out, all focus and aperture-related functions (as well as optical zoom when relevant) happen inside the lens, not in the body (in terms of lens components moving at least, not talking about the logic and control). Nowadays most lenses will have built-in motors to perform these tasks, and are controlled electronically by the body through the ...


7

I use my camera's LiveView display only when I also need to use its tilt-feature. Otherwise the rear screen is nearly useless to me. These situations come up for example nearly every time I use a tripod, and especially when I aim the camera up towards sky (stars) and it soon becomes physically impossible for me to get a good look in the viewfinder, or even ...


7

It is useful when making pictures from unusual positions: Overhead (e.g. in a crowd) Near the ground (without having to lay on the ground yourself) Self portraits (if the display can be flipped 180°) It can also be used to make shots from hip height without raising awareness of the subjects (they may think you are reviewing photos or changing settings, ...


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