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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), ...


34

What makes the difference on partially and fully visible moon? In a word: shadows. I cannot understand why the IQ is extremely diminished when doing the same with an almost fully visible moon. The second image does appear to suffer from lower sharpness and overall quality. However, even if the technical image quality factors were equal, most importantly,...


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 ...


19

When using manual focus you have to adjust the plane of focus using the focus ring to acquire correct focus. You will have to choose this yourself and if I understand you correctly you have not done this. Of course there is a slight chance that the lens will already be set to focus at the depth you want but they are slim indeed. Using a wide aperture will ...


16

The lens is not parfocal in either direction. What you have discovered is the difference between narrow Depth of Field (DoF) at longer focal lengths and deeper Depth of Field at wider focal lengths. The focusing error you introduce when you focus at 18mm and then zoom to 105mm is greater than the shallow DoF at 105mm even at f/8, so you notice how out of ...


13

Yes, manual focusing is more accurate than phase detect AF (except for the combination of very recent Canon camera + lens). Over at LensRentals blog Roger performed AF tests back in July / August 2012. For almost any combination of camera and lens, manual focus can (given enough time) be better than phase detect AF. Read the whole blog series if you want to ...


12

What you are showing isn't just a focusing screen. It is a focusing screen with two special focusing aids. First, it has a split prism, which works as a tiny rangefinder — when the two sides are aligned, the subject is in focus. Second, outside of that, the rough microprism ring gives a similar effect, with a different tradeoff between ease of focus and ...


11

If there are, I've never seen one. They do not offer the same comfort for focusing. On cheap lenses, I noticed you have to turn the front element to focus which does not give much grip and also rotated the front element which is not good if you have a polarize filter. Better lenses have a nice texture focus ring to let you easily change focus. There is ...


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

Yes, the D5000 has a Rangefinder option. When in manual focus mode, this replaces the exposure meter in your viewfinder with a rangefinder meter. If the markings appear to the left, focus is in front of the subject. If the markings appear to the right, focus is behind the subject. To focus, you simply turn the focusing ring in the direction indicated by the ...


10

Having recently gone through this exercise first-hand, I'll share my results. I bought a Helios 44-2 58mm F/2.0 (M42 mount) on eBay for very cheap. To use the lens with my Nikon D7000 body, I bought a Fotodiox Lens Mount Adapter which includes a removable infinity focus correction lens. Shooting with the infinity focus corrective lens, I was very ...


10

I propose some tricks that can be used with lenses that have mechanical coupling with the focus ring (Anything in this answer does not apply to focus by wire lenses like Zuiko Digital lenses that require power from camera body to focus): Rock the Focus Step 1: I Just try to focus quickly as best as possible, then, re locate fingers on the focusing ring ...


10

You'll never regret buying the focus confirm adapter once you forget how much you had to pay for it :-). "Auto confirm" is akin to "poor man's AF", and allows you to achieve, in many cases, close to AF results with far less effort or thought or concentration than pure MF takes in extreme conditions. With auto-confirm you have to "think" a lot less and can ...


10

You will want to use an automatic continuous/servo mode to photograph birds in flight (BIF). Most modern cameras support some kind of servo mode, even entry-level cameras. Using servo mode is only part of the solution to tracking BIF, however. More advanced cameras offer additional AF features, such as multipoint AF Expansion or Zone AF that will use more ...


10

Sadly for Nikon users, the F mount has one of the longest registers ever. (Mechanically) adapting a lens designed for a certain system to one with a shorter register is easy: just manufacture an extension tube of the correct length. The ability of controlling the lens will be mostly lost but this is less of an issue with lenses with mechanical aperture ...


9

Focus confirmation does indeed work. I have a D7000 (which is ergonomically very similar to a D600 - think of a D600 as a D7000 with an upgraded sensor) and have been using a Nikon 80-200mm f/4.5 AI on it perfectly fine. I just rotate the focus dial until the green confirmation dot shows up on the screen. An important concept to realize about a camera's ...


9

The image in the viewfinder is focused on the ground glass screen. The focused image converges on a 2D plane. (It's not like binoculars.) When you look through the viewfinder, your eyes focus on the image on the screen, which is at a fixed (virtual) distance. You can use the diopter adjustment to change your perception of the fixed screen. Glasses or ...


8

It is one of the lens design compromises they have chosen to make. While I don't think anyone can know for sure the reasons behind that decision, I can think of several likely ones: Zeiss's own most successful cameras are rangefinders, which do not auto focus. These are the only cameras they still make today. MF lenses avoid any complication from ...


8

You're misunderstanding the statement. "Pixel-peeping" during focusing is indeed a good way to get a sharp image. The statement "Pixel peeped images aren't likely to look sharp" means that the image won't look that sharp while you're doing the "peeping" because the viewing magnification is so high.


8

Zone focusing consists of choosing your aperture and point of focus so that everything within a desired zone or range of distances will be acceptably in focus. I'll take my original conclusion and put it here as it is the "simple" result of the long winded descriptions. A look through a series of relevant tables and a bit of playing will show you what is ...


8

Fortunately, it's not actually voodoo magic. You have set a fixed ISO of 400, and you're in aperture priority mode, which means you're choosing the aperture and not giving the camera control of that. That means the one variable the exposure program can change is shutter speed. When you tell it you want the exposure to be two stops darker, the only thing it ...


8

It is highly dependent on the design of each individual lens. Canon and Nikon lenses fall into two major groups regarding this: Lenses with full time manual focus. These lenses allow you to turn the focus ring at any time without fear of damaging the focus motor. The design of the lens allows the mechanism between the focus motor and the focus ring to slip, ...


8

For an image taken with a digital camera this information is stored and very easily accessible. What mode the camera was in such as Auto, Manual, Program, Aperture Priority, or Shutter Priority and more information can be found using the EXIF data that is stored along with the image. It is all included in the image file such as a .JPEG file in what we call ...


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

The biggest clue is the fact that the out of focus shot makes the moon appear to be significantly smaller than the in focus shot. With many Nikon telephoto zoom lenses as the focus distance is reduced the field of view is expanded. Some versions of Nikon's 70-200mm f/2.8 series of lenses have field of view of only about 140mm at the minimum focus distance ...


8

It is almost always necessary to manually focus astronomical subjects. The AF systems in most cameras can't focus on small, dim objects in the sky. Even when they can, their margin of error is usually too great to give the kinds of results most people desire when doing astrophotography. The same is true of focus markings on lenses that have them - they're ...


8

No. Focal length is characteristic of the lens. e.g. a 50mm non zoom lens will always show 50mm in the metadata / EXIF. For a zoom, like an 80-210mm the metadata / EXIF will show 80mm at the wide end, and 210mm at the telephoto end, and everything inbetween. What you are looking for in EXIF is "subject distance" which may or may not be supported depending ...


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