Posts Tagged ‘exposure’
Peter West Carey of DPS has a neat trick for always having a gray card “at hand”: he suggests using your hand as a gray card when you don’t have a card handy. You’ll need to start with an actual gray card for “calibration”:
In a nice even light, using spot metering and manual exposure mode, point your camera at the gray card. Set your ISO so it is not on Auto and maybe to 800, the number isn’t too important. Now adjust aperture and shutter speed until the camera metering is at zero, meaning it is not over or underexposed according to the camera. Next place your hand (I suggest your left hand) where the card was, with your fingers together. Ensure the center metering spot is completely covered by your hand.
What does the camera’s meter read now? Mine says the settings I had for the gray card are 2/3rds of a stop too dark for my hand. [...] This means whenever I point the spot metering at my hand, and my hand is in the light hitting my subject, I just have to adjust my settings until my camera thinks the exposure is 2/3rds of a stop too dark and I am set!
So basically, since the color and tone of your palms don’t change very much, you can use the difference between your hand and 18% gray for snap exposure judgements while shooting.
A new patent application by Apple is showing off some of the technology we may be finding in the next generation camera. The application, which you can read in its entirety here, mentions a few new features, among them the ability to select multiple focus points, allowing the the phone to take over and adjust the aperture, exposure and even post-process to get the best possible picture for those points.
A few other notable features mentioned in the patent include motion tracking for focus, automatic sharpening of key areas, and the possibility of a dedicated image processor (instead of the image processing hardware built into the A5 chip?). Of course we can’t be sure that these advances will make their way into the next iPhone or that they’ll see the light of day at all, but just the fact that Apple is taking this much of an interest in improving an already good smartphone camera seems to bode well for the phoneotographers among us.
(via Photography Bay)
Matthew Gore of Light & Matter created this beginner-friendly video tutorial on the three basic elements of exposure: aperture, shutter speed, and ISO. It’s explained with easy to understand illustrations and examples, and features graphics and sounds that are reminiscent of old 8-bit video games. You can also find a text-based version of the tutorial here.
So, from time to time, I receive requests to use my images for various purposes — like on a blog or a pamphlet or a calendar or the side of a zeppelin or for a urinal cake. Typically, if they are nice and they’re not going to be making a load of cash off where they’d like to use my image then I’ll let them use it as long as they give me credit. I’m especially generous with environmental interests and non-profits and ice cream manufacturers offering vouchers for all-you-can-eat tours.
But then there are the chumps (and chumpettes) who will be making a substantial amount of money off of the use of my image and I send them packing unless they pony up a fair amount of money. The latest version of this repetitive saga really got caught all up in my craw and so I felt the need to write a bit about it.
Even if you have a good command of using f-stop numbers and properly exposing photographs, you might not understand the math behind why f-stop numbers are what they are. Here’s a simple (albeit math-filled) explanation by Dylan Bennett of what f-stop is, including a simple trick you can use to memorize the f-stop scale.
Adam Dachis over at Lifehacker offers a simple method for correcting underexposed photo with any image editor that supports layers, inversion, and Overlay blending mode. Simply create a duplicate later, invert it, set the blending mode to Overlay, and then adjust the opacity to suit your taste. While it’s certainly not a pro photography trick — other techniques including adjusting the curves and levels may be better — it’s a quick and easy tip that may be good to know.
On January 1st of last year, photographer Michael Chrisman began shooting a solargraph by placing a pinhole camera in the Port Lands of Toronto and aiming it at the city’s skyline. Over the next 365, the rising and setting sun slowly exposed the photo paper inside. The total exposure time? 31,536,000 seconds. Instead of developing the image using traditional darkroom chemicals, he instead used a scanner to capture the extremely overexposed image — destroying the original image in the process — and ended up with the photo you see above. Those yellow lines you see in the sky shows the gradual shifting of the sun’s path over the course of 2011.
(via Toronto Star)
Image credit: Photograph by Michael Chrisman and used with permission
This might look like some kind of microscopic organism, but it’s actually a high-speed photograph of a nuclear explosion. It was captured less than 1 millisecond after the detonation using a rapatronic camera, which is capable of exposure times as brief as 10 nanoseconds (one nanosecond is one billionth of a second). The photograph was shot from roughly 7 miles away during the Tumbler-Snapper tests in Nevada (1952). The fireball is roughly 20 meters in diameter, and three times hotter than the surface of the sun.
Kaufmann’s Posographe is an intricate pocket-sized mechanical calculator invented back in the 1920s. Measuring 13x8cm and filled with tiny scribblings, the device allowed photographers to approximate the exposure values they needed by simply sliding around six small pointers.