Place a line from the zenith to the image circle's perimeter, anywhere, and then create dashes for measurement. Step 2: Use Pixel Counts to Create a Radius Line Snapping the end of a measuring line to the intersection ensure accurate zenith measurements. One-point lines (approximately five pixels) aligned to the image center help identify the exact center. These two givens, level image with a horizon around the perimeter and the image circle size, let us start to work on our calculations. We also need to know that the image circle is 24mm across on the film or your full-frame sensor. For the purposes of this article, this photo of a very-stern Abe Lincoln at the Lincoln Highway Memorial near Laramie, Wyoming, works. So, let's dive in: How do we do this? First, we need a photo taken with the lens pointed, level, directly at the sky. Let's imagine that we've discovered a meteor heading toward Earth and we want to track its progress. Cloud size could be measured for estimating the water volume they contain. Knowing the geometry behind this lens' scientific use opens a number of doors for interesting and creative projects. The orbits of planets could be plotted against the zenith to study their rotation around the sun. Tree canopies could be recorded from the same location to measure growth over months or years. Satellites could be recorded over a span of minutes for the same purpose. For instance, a comet could be tracked for many nights to calculate trajectory, speed, and direction. Nikon 8mm f/8 Fish-eye Nikkor: Scientific Useīut why? What use does the following process have? This process can be used to help measure object movement through space. These technical corrections make measurements with this lens possible. The Nikon 8mm from the early 1960s has exceptional correction to eliminate magnification shift over the image field and to provide exceptional radial symmetry from the lens' optical center, as the data we'll review show. Not all circular fisheyes can be used this way, and even those that can, the calculation tables provided by Nikon for this lens are specific to it. This article examines, in depth, how to use this lens for object measurement along radial lines emanating from the sky's zenith. This capability of this lens, specifically, means that the Nikon 8mm f/8 Fish-eye Nikkor has measurement capabilities for the placement of objects within the sky. 2X is one stop 6X is 2.5 stops.The video below shows how proper lens alignment allows the whole sky to be in frame with the horizon along the image's perimeter. Note that the EV compensation is a factor and needs to be converted to stops. When I looked up and saw this site, my fisheye was the only lens that crossed my mind! 5.Reproduced from data in the Nikon manual, this table also provides some added detail that I input from experience. With symmetrical architecture like this, a lot of times there will be a clear marker on the ground to signify the exact middle of the room. This was taken at the Gaylor Texan in Grapevine, Texas and this ceiling is absolutely massive. There’s no way you could capture this much of a ceiling with a normal lens. Doing this will allow you to capture a nearly 180 degree view of a scene while avoiding the distorted, crazy look of a fisheye lens. Just make sure your horizon is towards the middle of the frame. If you have a landscape without straight lines (buildings, trees, telephone poles, etc) you can sometimes position the lens in a way that it simply looks like a wide angle lens. Sometimes, you don’t want distorted lines but still need that super wide angle. Sometimes, a fisheye can be used simply to capture everything you want in a scene. Shoot Super Wide Landscapes Without The Fisheye Look Just be careful, you might get home and find your legs in the bottom of the frame -). The exaggerate this distortion, place the horizon dangerously close to the top of the frame. If you place the horizon in the middle of the frame, it will be perfectly straight across the entire image. One thing to note when using a fisheye lens is this: The further you move an object or line to the edge of the frame, the more distorted it becomes. Not every image is going to come out, but you can almost always walk away with a few keepers. To do this, simply cradle the lens with your left hand while using your right hand to pivot the camera body around. Next, you need to spin the camera 90 degrees counter clockwise. To get this radial-blur effect, simply slow down your shutter speed to around 1/25th of a second. When I’m shooting a reception, I get right in the middle of the dance floor and just shoot away. These receptions are usually in low light and are a challenge to get great images out of. Shooting a wedding reception with a fisheye lens can be an absolute blast.
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