Hot answers tagged

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 ...


63

Is there any significant benefit to having an SLR mechanism in a digital camera? Particularly in terms of a benefit that's large enough to make up for the liability of adding a mechanical part into a design where a solid-state alternative is available? Yes. Response speed for both autofocus and shutter release. The mirrorbox has a number of side ...


54

And with a digital camera, you don't need a hinged mirror as you can show the user exactly what light will be captured by just routing the sensor output to an LCD display. This is the reason for the rise in popularity of mirrorless interchangeable lens cameras (MILC). Without the mirror box, the camera can be smaller, lighter, less expensive, etc. Having ...


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.


27

Don't forget a major drawback that EVF's require power to compose, and are much harder on batteries if you spend a lot of time with the screen on. Also, as previously mentioned, because of delays, it is harder to follow moving objects with an EVF.


18

You won't be able to tell by looking at the film. When the film is exposed, the changes in the crystals in the film's emulsion are invisible, and the exposed film is said to contain a latent image. This image is made visible by developing the film into negatives from which you can make prints (or for slide film, into slides). After this, a fixer is used 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. ...


17

There are both advantages and disadvantages to EVFs. The very best ones with high-resolution and high-refresh rates are actually quite suitable for most uses when well-implemented. The main disadvantages are: Lag: There is a short lag between action happening in front of the camera and what you see. Dynamic-Range: EVFs are small LCD screens and have ...


17

Another disadvantage of using the sensor to generate a near real time preview in lieu of an optical viewfinder is the requirement to keep the sensor energized continuously. In addition to the increased battery usage, over extended periods of time this tends to build up heat which, as we all should already know, can affect read noise and thus the signal-to-...


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 ...


15

I suspect the major reason this is true for DSLRs is to get the lightning-fast focus times that point-and-shoot cameras don't have. The autofocus mechanism is not actually part of the main CCD/CMOS sensor, but a separate device in the camera body, and the mirror splits the light coming through your lens so that half goes to the viewfinder and half goes to ...


14

This is a great camera with a lot of advantages for a beginner. It's dead simple and very reliable. It doesn't even need a battery, except to meter. And the meter is great — a simple, direct needle which indicates the overall exposure of the whole frame. I find this much more enjoyable to use than the LED indicators used on newer fancier cameras. Combined ...


14

The Nikon FG-20 has an electronic shutter, which will not work properly if no battery is inserted. You can, with limited capabilities, still use the camera without a battery. Light metereing will of course not work, but the shutter speeds are also restricted to B and a mechanically controlled 1/90s indicated as 'M90' on the speed dial. Unfortunately, the ...


12

Just based on visual comparison, this lens appears to be a Helios 44M-4 58mm f/2-16. From the images you linked to, it appears that part of the lens is missing. In the 2nd image, around the lens barrel you can see what appears to be front element retaining clamps or springs. (Helios 44M-x Lenses, in order: 44M-4, 44M-5, 44M-6, 44M-7) How I found it: ...


11

Simple, it allows you to see exactly what the camera will "see" when you expose the shot. Nir has given you a part of the argument as well which is accuracy. In the "middle ground" of anything around mabye 20-100mm, building a rangefinder is not too difficult and Leica had adapters for longer and wider lenses if I am not mistaken. It takes some effort to ...


11

As @Sandor Dosa comented. It is a light leak. It is difficult to know where the leak happened. Prior for you to use the film (a faulty film from start) Your fault during mounting the film. Your camera has a leak. The film is jammed. You handling the film prior to send it to develop. The lab during the handling and process. The bad news is, as you stated ...


11

Usually, it does not affect or limit the aperture or shutter speed at all. Rather, it tells the exposure meter where the center is. In some ways, it's exactly like exposure compensation dials. If the camera has a program mode, it's essential information for getting exposure right. If it doesn't, like the Pentax K1000, it just shifts the exposure needle — if ...


10

An SLR (digital or otherwise) usually has an interchangeable lens mechanism and given that the "zoom" is a property of the lens, not the camera, it's not possible to tell you on the camera. Basically, all the zoom range is is the ratio between the shortest and longest focal lengths of the lens so, for example, a 10mm - 100mm zoom lens has a 10x zoom ratio.


10

The scale on the bottom right of the LCD display is the exposure compensation scale. That's where the camera shows the current exposure compensation setting. Except in Manual mode, when the exposure compensation display is hijacked to be used to indicate how far your exposure settings deviate from the camera meter's recommended exposure. So in "Av" mode, ...


10

It depends on the specific camera. The Pentax K1000, for example, only requires the battery for metering, but everything else is mechanical. On your camera, shutter timing is electronic and requires a battery — but according to the manual there is a special setting M90 which provides a 1/90th of a second shutter speed which is all mechanical and can be used ...


9

The "X" multiplier zoom is simply the longest focal length divided by the shortest and is a misleading number with very little value, even when properly understood, unless you know ether the tightest or widest focal lengths. A 5 to 50mm focal length zoom is technically a 10x zoom, but doesn't cover all that big of a range. A 70 - 400mm zoom on the other ...


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 ...


8

I have been working on a project which also requires, more or less, a webcam with HD quality (something like 720p) and an optical zoom lens. There are such things for sale ... but they are industrial-strength, and industrial-priced, such as pan-tilt-zoom cameras for high-end videoconferencing equipment. And, of course, there are the commercial cameras that ...


8

The main differences between compact cameras and DSLRs are mainly 3: Sensor size: compact cameras have small sensors, that give you little space to play with shallow depth of field, and give you a smaller dynamic (the ability to catch in the same shot bright and dark objects keeping details in both). Ability to use multiple, different, lenses: above a ...


8

Yes depending on what camera you have. Did you read the manual?


8

To a very good approximation: yes, assuming you've done the obvious and set your DSLR ISO to whatever film speed you're using. The definition of "ISO" is the same for film and for digital. There are a number of reasons why you might not get exactly the same exposure between the digital and film setups: ISO 200 (or whatever you're using) might not be ...


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 ...


8

There's a number of ways this can happen, but my best guess is that the camera door popped open at some point and then was closed, probably during film rewind, or depending on the position and frame count between recovered frames, at multiple times during your shooting sessions with the roll of film. One might think that accidentally opening the camera door ...


7

It would not matter if the strap is connected to the top or bottom of a camera body, the lens would contine to stick out. You can look at the videos of the black rapid strap to see what I mean, it attaches to the tripod mount on the bottom of a camera. The reason that camera manufacturers do not place camera strap mounting points on the boom is because most ...


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