It will handle large prints somewhat better, but I don't print as large as Manfred, and so far, I have printed only one image for which I think it would have mattered. I also prefer a large-photosite camera for one other purpose: night photography. I do exposures up to 10 minutes, and in hot weather, the sensor will tend to overheat.
That problem is worse with cameras that have small, densely packed photosites. However, for many purposes, it just doesn't matter, or it matters very little. For some purposes, I deliberately choose the crop-sensor camera because for some uses, the greater pixel density and lighter weight are both plusses. I am a member of a very old camera club that has some truly excellent photographers. One of the people who routinely wins awards and who does many types of photography far better than I do shoots with a Canon 40D--a crop sensor camera that is now 3 generations out of date.
Recently, I inspected some fairly large prints someone had done with images from a small Fuji, and they were beautiful. So, my way of thinking about it is that larger photosites offer some advantages, but not enough to make all of the other considerations in choosing a camera moot. The people who think they have to get a FF camera to do well are fooling themselves.
Originally Posted by dje. Yes Trish that is correct. For example, the 36MP D has a pixel size of 4. It's the ISO setting that is important rather than the amount of light. Satisfactory exposure can be achieved in low light with low ISO, wide aperture and long shutter speed which is fine for stationary subjects and a tripod mounted camera. But for sports and wildlife, the use of high ISO is often the only way to get good exposure with a satisfactorily fast shutter speed.
Absolutely invaluable information from all of the replies so far! I currently have a D which is hugely better than my old D70, but still find that noise can be at an annoying level for images taken in lowish light. I'd like to have a go at some wide-field astronomical images such as the Magellanic Clouds or things like planetary conjunctions for which the D doesn't really work well though it would do better with faster lenses. For images of birds and other wildlife I often have to crop tightly as they may not be conveniently nearby.
If I've understood everyone correctly, with the most modern sensors there is little difference between a FF 24 MP and FF 36 MP all other things being equal which means that one can't really go so very far wrong in decision making. This is most comforting! Originally Posted by GrumpyDiver.
Last edited by lukaswerth; 3rd May at AM. Originally Posted by lukaswerth. Images for large format poster printing can be around ppi depending on how close the image will be viewed. Screen images are different than images for printing because we must think about the pixel dimensions of monitors, TVs, projectors, or display, rather than PPI. Use PPI for printed images, but use pixel dimensions of the image are what really determine the size of the image and quality of how it will display on the web or devices.
The idea has been for many years that images should be saved with a resolution of 72 PPI. Each monitor is different and has a different resolution, so it makes it difficult to design a website that contains images that will display perfectly on every type of display. Over the years, technology has improved and so has the quality of our displays. Most popular are Apple's new retina displays that are on the most recent Macbooks, iPhones, and iPads.
If you're a web developer, check out some ways people are designing for retina or high pixel density displays. Just like web images, images for projectors should match the pixel dimensions of the projector.
As with computer monitors, projectors also have their own display dimensions. For example, most aspect projectors have a display of x pixels, so an image that is x pixels with a 72 PPI resolution would be an ideal image size to be displayed from a projector.
Learn more about projector display. Web images work differently than printed images. If you are going to print it you need between and dpi. Of course, we are talking about generalizations because each monitor and each printer will have slightly different resolutions as well.
Anything bigger than that will only be taking up space on your hard drive. Open the menu for the image size and in the popup window, you need to tick the Resample Image box. You can also choose to tick the Constrain Proportion if you want the measure to adjust according to the changes you make. So the width adjusts when you change the height and vice versa. Notice the pixel size is x This is web resolution and is the exact size of all the images in this article.
The size in inches is irrelevant when posting online — only the pixel size matters. Now, if you still want to change the file size without resizing anymore, you have to do it when you save the image. Before saving your photo you can choose the format you want:.
The most common, and therefore easier to share is TIFF. As such, it must match the lens. The diameter of the lens at the point where it is attached to the camera will give you an indication of the size of the image sensor. For professional and fine art photographers who must have absolutely top quality photos and are likely to produce large prints, the difference in image quality offered by big image sensors plus their matching superior lenses, better firmware and such is critical.
For everyone else, whether or not the size of your pixels matters will depend on your plans to shoot in less-than-ideal lighting conditions or to print enlargements, or if you really care about details in your pictures. Lossless data compression seems a bit like a magic trick. Its cousin, lossy compression, is easier to comprehend.
Lossy algorithms are used to get music into the popular MP3 format and turn a digital image into a standard JPEG file. They do this by selectively removing bits, taking what scientists know about the way we see and hear to determine which bits we'd least miss. But no one can make the case that the resulting file is a perfect replica of the original. Not so with lossless data compression.
Bits do disappear, making the data file dramatically smaller and thus easier to store and transmit. The important difference is that the bits reappear on command. It's as if the bits are rabbits in a magician's act, disappearing and then reappearing from inside a hat at the wave of a wand. The world of magic had Houdini, who pioneered tricks that are still performed today. And data compression has Jacob Ziv. LZ77 wasn't the first lossless compression algorithm, but it was the first that could work its magic in a single step.
Photo: Rami Shlush. D, MIT, National Academy of Engineering, U. The following year, the two researchers issued a refinement, LZ Without these algorithms, we'd likely be mailing large data files on discs instead of sending them across the Internet with a click, buying our music on CDs instead of streaming it, and looking at Facebook feeds that don't have bouncing animated images.
Ziv went on to partner with other researchers on other innovations in compression. Ziv was born in to Russian immigrants in Tiberias, a city then in British-ruled Palestine and now part of Israel. Electricity and gadgets—and little else—fascinated him as a child. While practicing violin, for example, he came up with a scheme to turn his music stand into a lamp.
He also tried to build a Marconi transmitter from metal player-piano parts. When he plugged the contraption in, the entire house went dark. He never did get that transmitter to work. When the Arab-Israeli War began in , Ziv was in high school. Drafted into the Israel Defense Forces, he served briefly on the front lines until a group of mothers held organized protests, demanding that the youngest soldiers be sent elsewhere.
Ziv's reassignment took him to the Israeli Air Force, where he trained as a radar technician. When the war ended, he entered Technion—Israel Institute of Technology to study electrical engineering. After completing his master's degree in , Ziv returned to the defense world, this time joining Israel's National Defense Research Laboratory now Rafael Advanced Defense Systems to develop electronic components for use in missiles and other military systems.
The trouble was, Ziv recalls, that none of the engineers in the group, including himself, had more than a basic understanding of electronics.
Their electrical engineering education had focused more on power systems. It wasn't enough. The group's goal was to build a telemetry system using transistors instead of vacuum tubes. They needed not only knowledge, but parts. Ziv contacted Bell Telephone Laboratories and requested a free sample of its transistor; the company sent In , Ziv was selected as one of a handful of researchers from Israel's defense lab to study abroad.
That program, he says, transformed the evolution of science in Israel. Its organizers didn't steer the selected young engineers and scientists into particular fields. Instead, they let them pursue any type of graduate studies in any Western nation. Ziv planned to continue working in communications, but he was no longer interested in just the hardware.
He had recently read Information Theory Prentice-Hall, , one of the earliest books on the subject , by Stanford Goldman, and he decided to make information theory his focus.
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