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The image is sharpest at the focus distance. Many lenses have markings that roughly indicate that distance but you can also extract it from EXIF data shot from a digital camera. Sharpness decreases away from the plane of focus. Depth-of-Field is simply a concept to describe a range of distances which are sufficiently sharp. Sufficiently sharp depends on the ...


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It's hard to tell without pictures, but there are not many possible explanations that seem likely. The most probable thing that comes to mind is lens fungus. You may have to take the lens apart to remove it. Use a cleaner with about 70% isopropanol (also called isopropyl alcohol or IPA).


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Never forget: depth of field is a myth. The term is a convenient shorthand for a standard of how much defocus is acceptable, and is dependent on the ultimate size of the print or level of magnification in examination, as much as the magnification on the negative or sensor. At the highest resolution examination, even with a very small aperture, the plane of ...


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The clearest image of an object is always when the object is in focus — at the plane of focus. That is, for a given lens of focal length ƒ, when the lens is positioned a distance v from the camera sensor, then an object at distance u from the lens is in focus in accordance with the thin lens approximation, ƒ-1 = u-1 + v-1.


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If your variable ND filter has threads on the front, then you can attach any sort filter you wish to the front of it, including square filter holders. It can be tricky screwing filters onto the front of ones that rotate, such as your variable ND, or polarizers, but it can be done. I sometimes do this with my standalone polarizer filter mounted onto my lens, ...


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Lens makers strive to make lenses that deliver a faithful image. This has never been achieved, because all lenses suffer from aberrations (optical jargon for error). There are 7 major aberrations. To mitigate, lens makers construct a complex array consisting of several individual lens elements crammed into the lens barrel. Some are air-spaced from one-...


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Most filters have threads on both sides and can be stacked. But AFAIK the front side of a variable ND rotates, which makes it very impractical with a filter holder and many won't have a thread on the front. But your filter holder can likely accept several filters.


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It means less distortion, less color aberration, less vignetting, a bit more sharpness. This said the smartphone-ish look of your pictures could come from the sensor or the post processing and have nothing to do with the lens.


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Your question seems to be based upon an assumption that a human viewer can see the difference between "blurry" and "in focus" at the system limits of a lens system. This is usually far from the case without magnifying the results by a large factor. Can we use the imaging of the convex lens on the screen to explain hyperfocal distance? Not very well. Why? ...


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"Hyperfocal" refers to the condition where depth of field allows the lens to be "in focus" from some minimum distance to infinity. This depends on a core assumption: the size of the acceptable "circle of confusion," which is determined by the actual aperture diameter and lens focal length, but also by the amount of enlargement the image will receive before ...


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Lens cleaning fluid and lens cleaning tissue/cloths are ridiculously cheap. Even the premium "name brand" stuff is cheap. Get some and clean your lens properly. Never apply the fluid directly to the surface of the lens. Rather, put a few drops on the tissue or a soft, lint free cloth and wipe the lens in a circular motion from the center to the edges. If ...


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I have seen lenses with permanent visible fingerprints that "ate" into the coating on older lenses, which is why I say that your concern is reasonable, but the risk is still quite low with modern lens coatings. Most modern lens coatings are now quite resistant to skin oils, but one should always take care to keep the lenses as clean as possible. The risk, ...


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I just want to complement Itai's answer. A step-up ring is a better scenario (having a 77mm filter on a 72mm thread) But when the difference requires a lot of rings, let's say you need to use 8 rings, the filter is now further away from the lens, and some flaring could be noticeable. Of course, the pro is that for expensive filters you could buy just a ...


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A step-down ring is required to physically mount the 72mm filter on a lens with a 77mm thread. Since this is a step-down adapter rather than a step-up, the field-of-view of the lens may become partially obstructed, causing severe vignetting or even appearing visible at corners of the frame. Essentially, there is no pro for doing this, only downsides because ...


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The release button on your adapter seems to be missing. You need to see if you can use something to press the spring-loaded switch that seems to be visible in the hole left by the missing button.


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Panorama's. Centre Nodal Point. I wrote this for myself sometime back when I was considering buying a second quick release plate for my arca swiss style tripod which led me to investigate if doing so could improve the parallax errors in the panorama photo's I sometimes stitch together using Hugin open source software. The Centre Nodal Point (C.N.D.) is ...


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Geometry says you should need roughly an angle-of-view of 80° which is what you would get from a 12mm lens on a Four-Thirds sensor. The key is to understand that the aspect-ratio of the sensor is 4:3 and to capture a table of 36"x36" you need to fit at least 48"x36". This has a diagonal of 60" and the angle-of-view of lenses is specified according to their ...


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Simple trigonometry shows that the angle of view needed to capture a 1m wide surface from 1m should be on the order of about 53°. That's approximately a 35mm lens in the full-frame world - with an MFT crop factor of ~2, that should be about a 17mm lens on your rig.


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You can find a teardown of a similar model at iFxit. Sadly the content is too vast to copy it over, so you will have to cope with an external link: https://www.ifixit.com/Device/Polaroid_One-Step_600


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Lenses intended for still photography do not specify "megapixels". The designation, with respect to lenses, has no use or meaning for still photography. However, many C/CS mount lenses intended for video use do specify "megapixels". If you need to know more than that it is potentially relevant to video, consider asking a group of videographers, or the ...


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