Hot answers tagged

49

You're not doing anything wrong. You're just finding the limits of the camera/lens combination you are using. The EF 50mm f/1.8 (in various versions) has been known as the "plastic fantastic" for a long time. For what it can do at what it costs, it is a fantastic value. But it isn't really a fantastic 50mm prime lens when compared to many others that, ...


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 ...


11

It might be best if you post an example image, but in any case, there are a few things to bear in mind. First, shooting at such wide aperture provides very little leeway between the near and far limits of depth of field. Using a depth of field calculator, you will find that at 6 feet from the subject, only 4 inches will be in focus. Should your lens be off, ...


9

The stars aren't black; the spaces between them are. (or rather, dark blue) The brighter bits between that dark ones are the defocussed stars. Due to the defocussing, they have grown in apparent size, overwhelming the blue background. Think of a real star in the sky which is really just a point, but viewed through a defocussed lens appears as a disc.


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.


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.


6

If I'm getting the question correctly, it is about whether at infinity focus you ought to use wider apertures like f/1.4 or narrower apertures like f/11 to get the sharpest results? The answer is, it depends... First let's look at what depth of field actually is at infinity focus. The depth of field depends on three things: Focus distance, focal length, ...


6

Both sides of the formula are always equal (for theoretical, thin lenses; for real lenses, the formula is only an approximation). What it says is where you should place the image plane (the film or the sensor) to have a sharp image. In practice focal length f is fixed (because you have a prime lens, or because you have choosen the desired focal length of ...


6

The miniaturization effect that can be created with a tilt shift is due to manipulating the perspective (angle/distance/field of view) and spatial relationships; while simultaneously creating a shallow depth of field which is entirely contradictory. When a lens, or your eye, is focused very close there is very little that can be in focus simultaneously. ...


5

Typically when using back button focus you will want to use a Continuous focus mode to gain the most advantage from un-linking the focus button from the shutter release button. [Believe that would be AF-C on most Nikons, AI Servo on Canon] If you want it to change focus/for the focus to be able to change, press the button. If you want it to stop changing ...


5

At best it could only be a very rough estimate. Why is this so? Because ultimately depth of field depends on factors that the camera does not know and which may be, and often are, changed after the image is captured. Among them: Display size. The more an image is enlarged from the size of the image projected by the lens onto the camera's sensor, the more ...


5

The Fuji X-T3 and X-Pro2 (among others) have a focus assist feature called Focus Peak Highlight that shows what is in focus by outlining items in both the EVF and rear LCD that are in focus. This display changes with lens aperture (roughly) indicating near and far range of sharp focus. I believe other EVF camera systems have equivalent features.


5

Cinematography solved this problem long ago with the split diopter. It's literally just half of a screw-on diopter, just like so-called "close up filter" (although it doesn't filter anything, it's called that because it mounts to the lens like other front-mounted actual filters). Split diopters don't see much use in photography, but they used to be used in ...


5

Your issue probably has nothing to do with focus or how sharp your lens is at various focal length/aperture combinations. You're using a 1/160 exposure time with 300mm focal length on an APS-C size sensor. Camera movement is almost certainly what is causing most of the blur you see. If you use the same ISO and open up the aperture three stops to f/5, your ...


5

Unfortunately, as you've found, Nikon's in-body autofocus adjustment doesn't allow for different values at different focal lengths, apertures, or focus distances. Your suspicion is correct that those parameters can all change the adjustment required for perfect focus. A common example is a phenomenon called focus shift: lenses with fast maximum apertures ...


5

When the object is 50 meters away, how do you know that the camera is focused at a distance of 50 meters? That object will be the sharpest. Focus aids like autofocus systems can help, and there are various ways to ensure accurate manual focus. Is it possible to be laser-measurement precise with a camera designed for photography? No. That's not what they ...


5

The only option to focus is to change the distance to the subject. Basically, yes. Is there any existing workaround? A. Some rails are indeed one workaround rather than moving the tripod. There are some simpler models, like just a sliding plate on the head, like this one of the same brand. B. Some other has some sliding bellows for both elements, the ...


4

The problem with lenses wide open (gross generalization coming) is softness moving toward the corners - and this will be there no matter the exactness of your focus. The problem with focus and recompose is that it’s very easy to minutely change the distance to which you are focusing...not that you’re actually refocusing but that by changing the camera ...


4

Minimum focus distance means minimum focus distance of the lens (unless additional accessories are added). Lenses focus at only ONE precise distance, period. Depth of Field adds to that (plus and minus, as an acceptable zone) only providing an approximate "good enough" sharpness zone as defined by CoC (Circle of Confusion). Depth of Field numbers of say 2 ...


4

Potentially. It could also be that your measurements are slightly off. To find the perfect distance, you can focus on infinity, and then slowly move the lens nearer, until the picture is sharp. That is the correct distance; however, you should give it an extra tenth of a millimeter or two, to avoid issues with temperature changes or slight movement when ...


4

Here are a few things about "AF points" that a lot of folks don't know: Most AF "points" are larger than the squares used to represent each one in your camera's viewfinder. An AF "point" is defined by a set of two lines on the AF sensor that measure light coming from the same point through opposite sides of the lens. Most areas of sensitivity are ...


4

What you're after is the original usage of tilt and shift -- as a technique, it's called scheimpflug and is handled by adjust the tilts and swings to control the focal plane so that the planes of intended focus, of the front standard (standing in for the iris plane of the lens) and the film all meet at a single line somewhere in space (for landscapes, where ...


3

tl;dr - in theory, sure. In practice, I've found that it isn't really needed. In theory, yes, one could use the hyperfocal distance (HFD from here on out) to ensure that all subjects are reasonably sharp. That being said, an important consideration for "sharpness" and HFD is the print size and viewing distance of that print. If you figured out some great ...


3

Depends at least on the depth of field. For example, if you have 85mm f/1.2 on a full frame camera, and do a head&shoulders portrait (distance: 1.65 meters), the depth of field is 12.3mm in front of the focal plane and 12.5mm in rear of the focal plane. What are the chances that the camera moves so that the subject is no longer close enough to the ...


3

As this is the photography forum I will try to make a good approach using one. You need a camera with some kind of live view preferable. Get a tripod and position your camera pointing to the sheet of paper. I think a lower angle than the one you are using is probably more dramatic. Prepare a grid. Take a piece of cardboard, pets say size tabloid or A3, and ...


3

Pretty good picture given the camera. But it is likely that at very close range, the camera lens is soft (a true macro lens is designed to be sharp at very close range (and is not a zoom, which makes things easier...)). When shooting handheld, you can also move a bit longitudinally between the time the camera focuses and the time the picture is taken, ...


3

It's hard to tell without more information & EXIF data. Here are some possible explanations (and why more info is helpful) If using "One Shot" focus mode, if a subject (or camera) moves after the camera locks focus then it will not re-focus. AF point review will indicate which AF was used to lock focus, but it is an indication of which AF point was ...


3

Here's a montage of both photos: Foreground is taken from your first picture, background is taken from the second picture with a gaussian blur (radius 13). So there's nothing special, just the defocussing.


3

None of these cameras is an SLR, nor is there an integrated rangefinder (some Silette models had a rangefinder, this one has not). These cameras are indeed intended to be focused by using a well calibrated guess, a measuring tape, or an attached rangefinder accessory. The manuals included depth of field tables. Mind that the lenses are not very fast, and ...


3

The two major options are: Zone focusing. Set an aperture and distance so that the subject will fall within the depth of field. You can try hyperfocal distance – "F8 and be there." Use a rangefinder accessory. Search for "Ideal rangefinder", "pocket rangefinder", and "Lomo rangefinder" for some options. These work like rangefinder cameras, but you read ...


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