88

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 ...


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

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 ...


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 ...


9

Ideally it should be possible as the distance from the lens mount to the sensor or the film plane should be the same. But in real life I doubt it. After all, if there is just a tiny difference between the distance on the two cameras, your focus will be off.


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 ...


8

1) Manual focus means you must turn the focus ring to change the focus distance of the lens. Anytime the camera moves the focus point of the lens you are using autofocus (AF). With the Canon EOS system you use the AF/MF switch on the lens to select Manual Focus (MF) or Autofocus (AF). Other than a few exotic big white Super Telephoto lenses that have an ...


7

You'll find most split-circle focusing screens in manual focus film SLRs. In these cameras, the mirror is very efficient, and reflects all of the light up into the viewfinder. A little gets diverted for the exposure metering, but most of the light goes up and hits the focus screen. On autofocusing cameras the mirror is less efficient, as part of the light ...


7

Most digital cameras include the shooting mode, the metering mode, and even the focus mode in the EXIF information. The EXIF information can be viewed with most photo processing applications such as Adobe Lightroom or the software that came with the camera. Not all applications will display every field of the EXIF data, so you may need to try more than one. ...


7

From my reading, the amount materials within a "handheld" lens expand / contract over, for example, 15C is so minimal it's not worth thinking about. However this really becomes an issue on large telescopes, both refracting and reflecting (even more so). Why? As a (rough) example, let's imagine a large reflecting telescope which has a body length of 3m, ...


7

The Nikkor (i.e., Nikon-made) 55-300 is an AF-S lens and should autofocus on your Nikon D3300. Why you think it's manual focus only, I'm not sure. If the lens is a Nikon-made one, but designated as AF, that doesn't mean it's manual-focus only--just that it will only autofocus on a body with a focus motor. You'd need to get a D7x00 or higher end Nikon body ...


7

No. The incremental cost in actually providing modern features including priority and program modes is very, very small — but the reduction in potential market would be enormous. Because of this, such a camera would probably be more expensive than cameras with features made for the mass market — including higher-end models aimed at enthusiasts and working-...


6

I am not familiar with this exact lens and camera model, but with similar questions related to Sony Alpha cameras and manual focus lenses. I assume your camera gives an error message similar to the following: "Check the lens attachment. If the lens is not supported, you can permit use of the lens in the custom menu." I suspect the reason for this is that ...


6

The AF confirmation actually works on a very similar principle to the old focus screen, in that they compare two different optical paths in order to determine exactly how in or out of focus the image is. The exact technique is different, but they accomplish the same end goal. The only difference is a computer is comparing the sides of the circle for you. ...


6

Yes, it's normal behavior. The reason you're having problems is that the 5DMkIII has an LCD overlay in the viewfinder. This overlay is used to give you grid lines you can turn on and off and different AF point displays. Without power, the LCD becomes opaque. This behavior is identical in Nikon cameras with an LCD overlay in the viewfinder, and has long ...


6

To the best of my knowledge all current Canon "L" lenses have ring type USM focus motors, other than the TS-E lenses that are designated "L". They have no focus motor of any kind as they are manual focus only lenses. If the lens has ring USM then you can move the focus ring at any time without fear of damage. If the lens has Micro-USM and the focus ring ...


6

A focus motor without autofocus can be useful for manual remote control of the focus. For your particular example, the Rokinon 24mm, I think that the information on the Lenshero webpage is simply wrong.


6

These focusing aids are part of the focusing screen, which is part of the viewing system within the camera body. Some cameras have user-interchangeable focusing screens, others have factory-interchangeable focusing screens, and some cameras have focusing screens that cannot be changed. See for example Canon's leaflet on focusing screens here: https://www....


6

This camera appears to essentially be a phone camera placed into a body made to look like a compact 'point and shoot' or small advanced compact camera. Most of the "lens" is just window dressing for the tiny lens located in the middle. In some of the product photos there appears to be a flat, screw on "protective" filter in place to make the "lens" look much ...


6

That lens is listed as compatible with Canon EOS-M cameras, which are interchangable lens cameras. The PowerShot line of cameras does not have an interchangable lens. So, no, it's not compatible with your SX530. I can't speak to the quality of the lens, but the lack of any reviews on Amazon says something... As does the fact that a simple Google search for "...


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