![]() ![]() Still, corner performance relative to the center is quite good across the entire range for a superzoom, especially for one with this amount of range. Some of this is due to the small maximum aperture causing stronger diffraction. ![]() Corners got softer above 1000mm equivalent, but so did the center. At intermediate focal lengths, corner performance was actually quite good, only slightly softer than the center. Much of the softness and artifacts is due to the strong geometric distortion correction needed at 24mm equivalent (see below). At maximum wide angle, corners are soft with reduced contrast and rough edge artifacts. Wide open, our sample's lens was well centered, with all four corners showing roughly the same performance. in the corners in camera JPEGs, and there's virtually none to low C.A. Thanks to effective in-camera chromatic aberration suppression, there's low to moderate C.A. Obviously, a lens that doesn't require such correction and is also sharp in the corners to begin with would be preferable, but relaxing constraints on distortion brings other benefits in the lens design, such as a much more compact, lower-cost design than would be otherwise possible.Ĭhromatic Aberration. If you look closely at the corners in the P1000's wide-angle JPEGs, they are soft and detail is a little rough with straight edges in the resolution target looking jagged. BIG APERTURE NIKON ZOOM LENS FULLAnd in the case of the P1000, the image circle does not cover the entire sensor at wide angle (we've seen this with other cameras as well), requiring even more interpolation back to full 16-megapixel image dimensions. There is however going to be a loss of resolution as well as possible interpolation artifacts as a result of such strong correction, because pixels in the corners of the frame are being "stretched" to correct for the distortion. ![]() BIG APERTURE NIKON ZOOM LENS SOFTWARENikon's free ViewNX-i software and Adobe Camera Raw for example automatically reduce geometric distortion in NRW files, producing distortion similar to in-camera JPEGs. High distortion is quite common at wide angle these days, and most raw converters will automatically correct for it. Uncorrected distortion at full telephoto is estimated to be just over 0.4% pincushion, which isn't is pretty low. Also note how the image circle does not cover the corners of the sensor at maximum wide angle, leaving them very dark. Uncorrected RAW files: When converting NRW files using dcraw (with no corrections applied), we see that actual barrel distortion at wide angle is very high, at about 4.4%. Uncorrected RAWīarrel distortion at 24mm eq. The Nikon P1000 supports raw capture, so we can see how much distortion correction is taking place during JPEG processing by examining the NRW files with a converter that doesn't apply corrections as shown below. This is the tendency for the lens to bend straight lines outward (like a barrel - usually at wide-angle) or inward (like a pincushion - usually at telephoto). At full telephoto, distortion was difficult to accurately measure with the target we use for superzooms, but it appears be quite low, so we're estimating it as less than 0.1% pincushion distortion. ![]() At full wide angle, we measured just over 0.2% barrel distortion in JPEGs. JPEGs: Thanks to effective in-camera distortion correction, there's low geometric distortion in the P1000's JPEG files at normal distances. Pincushion distortion at telephoto is less than 0.1 percent Barrel distortion at wide angle is about 0.2 percent Low geometric distortion for in-camera JPEGs high barrel distortion in uncorrected RAWs at wide angle. ![]()
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