86

Through-the-lens focusing cameras had focusing screens — usually ground glass or fresnel lens (related: What is a focusing screen?). View cameras (the old-style large cameras with bellows) projected the image onto the focus screen. The photographer directly inspected the image on the focusing screen (perhaps using a loupe to magnify areas of the image), ...


25

How did photography work before auto-focus was invented? Pretty well for those willing to learn how to do it with the tools we had at at the time. The same is true now. The only difference is that now we must learn how to tell an AF system to focus on the part of the frame we want it to bring into focus. Presumably everybody used manual focus. But here's ...


11

There are diferent topics here. 1) A toy camera, and some new cameras, for example survilance cameras, some phone cameras do not need to focus because its focus range is very extense. Normally this is due two elements combined. A wide angle lens, and a small aperture. So there is no need to focus at their designed range. Try to have in focus a very close ...


10

What you're missing is that most compact cameras will use an electronic viewfinder, rather than an optical one, if they have a viewfinder at all. Apparently a lot of folks don't mind composing and shooting from an LCD screen on the back of the camera. The Powershot G's viewfinder has several drawbacks. It can be blocked by an accessory tube. It only shows ...


8

To suppliment the answers on focusing aids in SLR cameras meant to be manually focused, let me give you a link to hyperfocal distance which is used in fixed focus cameras. My parents’ (later handed down to me) looked like this, so it was an Instamatic X-15 circa 1970. The first picure is a higher-end model that has a built-in light meter (so I guess the ...


8

The current answers explore manual through-the-lens focussing and fixed focus cameras, and do a good job of explaining them, but they miss another approach - distance estimation. For example, my old 1960 Kodak Retinette is not an SLR, and there is no through-the-lens focussing. However, it is not a fixed focus either. Instead, you estimate how far away the ...


8

Two things contribute to this phenomenon: The light collected by split image focusing screens are edge rays collected on the outer areas of the front element of the lens. With lenses that have smaller maximum apertures the focusing screen is trying to find light from an area wider than the front element of the lens. In most situations focusing and metering ...


8

Are optical viewfinders on point and shoot cameras now dead? Probably, yeah. I notice that in the 2011 answer to the other question you link, Itai suggests that they were then a "dying breed", and that seems to have become completely true. I did a search on Digital Photography Review's database of all compact cameras with any type of optical finder, and — ...


8

Electronic viewfinder Pros: Potentially smaller and lighter camera bodies and lenses (particularly wide angle lenses) Can zoom in to verify precise focus and depth of field Can see (almost) exactly what the camera sees, even in low light Can superimpose more complex data over the image (e.g. zebra stripes, focus peaking); see note below. No mirror assembly ...


7

DSLRs have a direct, optical path through the lens. (Well, a reflected direct path.) You are seeing the scene with your eyes. Mirrorless cameras with a viewfinder actually use a small LCD screen — we call this an electronic viewfinder, or "EVF". You are seeing the image read from the sensor processed for viewing, not the scene itself. Both approaches have ...


6

I know how the focus points are painted on the mirror.. Not really, because I've never seen focus points or anything else (intentionally) painted on a reflex mirror. It would be out of focus. Technically, those that do it the way you think you are describing etch them onto the focusing screen, which is located in the roof of the mirror box. But other ...


5

Without having more information on how exactly you took your image, and without the possibility to reproduce this effect, one can only guess. I see three possible causes for a sun reflection that is visible in the view finder, but does not appear in the image that is taken by the image sensor: Automatic aperture control Possibly you took your picture with ...


5

I believe there is a misconception here. Doing a manual white balance, will not preserve the look of the lighting, it will try to neutralize the light and thus the rendition of color. How white balance works If you have a room with warm (incandescent) light, the light has a very yellow/orangish tone to it. Any object that is reflecting the light will ...


4

The simplest camera you can have, something you can easily build at home, is just a cardboard box with a pinhole. You'll get a focused image right on the film (albeit inverted). This also works with human eyes - if you're near-sighted and don't have your glasses, you can get a perfectly focused image just by forming your fist in front of your eye to let just ...


4

An optical viewfinder can never have any lag, since it's optical it operates at the speed of light. On the other hand with an optical viewfinder you will not see exactly what you will get in you image file. Exposure, white balance, color and image crop (3:2, 1:1, ...) settings are not visible in the optical viewfinder, but can be visible in the electronic ...


4

"95% accurate" - there isn't such an optical viewfinder. IOW there isn't an optical viewfinder which will give you guaranteed the final result with at least 95% accuracy. Most probably you mean 95% coverage - this means that you see through your viewfinder only 95% from your photo area. So, it is nothing related to the bokeh. Speaking simply, as we all (...


3

The light entering the camera from the viewfinder will only affect metering when the mirror is down. When the sensor is exposed, either to take a picture or to enable Live View, the mirror will be up and will block pretty much any light entering the viewfinder from reaching the imaging sensor. This is true of just about any DSLR with a reflex mirror whether ...


3

As with any lens on a dSLR, the viewfinder and liveview will show you any lens effects. The lightpath into the camera travels through the lens first before it is reflected by the mirror up into the viewfinder, or (in liveview as the mirror is locked up) before it hits the sensor to be turned into image signals that are sent to the LCD. So however the lens ...


3

On an SLR, since the image is transmitted by the attached lens regardless of whether you use the optical viewfinder or live view, both live view and the optical viewfinder will show what the sensor sees, including the effect of any filters or modifiers attached to the lens. Indeed, live view is a feed directly from the sensor. Not all viewfinders offer 100% ...


3

Let me try to swing a not-too-technical explanation of this… Start out with "what do I want to achieve?" Accurate colour, or a more 'emotional' representation of what the scene feels like to be there. The human eye corrects for white balance without you really being able to tell it's doing it, but by the time an image is on paper or a screen, that self-...


2

The optical viewfinder does not require any power. Take a look at the numbers in the "battery" section of each of the following links (at the very end of the article): http://www.imaging-resource.com/PRODS/canon-5d-mkiii/canon-5d-mkiiiA6.HTM http://www.imaging-resource.com/PRODS/canon-t5/canon-t5A6.HTM http://www.imaging-resource.com/PRODS/canon-70d/canon-...


2

re: Why anyone would want to hold even the lightest camera out at arm's length baffles me. Some people, it seems, can't envision the boundaries of the frame when looking through the classic eyepiece. That's probably because the eye is not a direct percepion; rather a mental image is built up. I recall being impressed that my 3-year-old nephew could ...


2

You probably can, and a Canon service centre would be able to do it, but it would be worth weighing up the cost, if it's in the optical viewfinder, then it won't affect any images because the mirror that is behind the lens that passes the image to it gets raised when the image is captured to send the light coming in through the lens onto the image sensor ...


2

Aside from the Leica Ms, there is one very notable MILC with an optical viewfinder, which is the Fuji X‑Pro 1. Its fixed-lens little brothers, the X100 series of cameras, also sport the same "hybrid" viewfinder which can be switched between an OVF with LCD overlay and an EVF and APS-C sensors. And unlike the X-Pro 1 have leaf shutters that ...


2

We made an awful lot of bad photos. Shooting candids, I figured that between bad exposure and bad focus that 60% printable shots was par for the course. Auto exposure cut the rejects in half. AF came in just in time to fix my decreasing aging vision. Now, I figure that unless I do something stupid, then rejects for focus/exposure will be only a few ...


2

This is answered in detail in another post: How are the red focus point indicators displayed on a DSLR's focusing screen? However, all of the DSLR cameras I am familiar with (OVFs) use an overlayed display in a manner similar to the image Michael posted. I updated that image to better explain how that works (some cameras use separate mirrors as shown in ...


2

Manual focusing needs to be handled differently with an EVF. Since most EVF are much lower in resolution than the sensor, it is hard to judge best focus by sight, requiring the use of focusing aids like peaking or focus magnification. On the other hand, when these aids are used (which might require additional operating steps), manual focus will often be ...


2

You may have astigmatism that is insufficiently corrected by your glasses. Astigmatic eyes have multiple focus points that create double images. The high contrast of the moon against a dark sky makes the fainter "ghost" image more visible. If this is the case, you may be able to replicate the effect with a high contrast image, such as black text on a white ...


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