![]() When you're talking about the crop ratio (how much of the picture has been cut away), "100% crop" means the image has not been cropped. In this usage, the term gives you no information about how much of the original image has been cropped (i.e., cut off). When you're talking about the scale factor, "100% crop" means "this is a crop of the original image that has not been scaled" - in other words, each pixel in the reproduced image matches a pixel in the original image. For example if you take an original image that's 4000 pixels across and you remove 1000 pixels from either side to leave a width of 2000 pixels, you could refer to it as a "50% crop" (whether the percentage is applied to the linear or areal ratio is for another discussion). The amount of image removed is also often referred to as a percentage. For example you take a picture of a bird surrounded by a lot of blue sky and remove most of the blue sky so that the resulting image is mostly filled by the bird itself. The amount of scaling is often referred to in terms of percentages, where 100% means no scaling, 100% means upscaling.Īn image is cropped when some portion of it is removed. All other things being equal, an uncropped image appears smaller when downscaled and larger when upscaled. There are two factors at work here - how the image is scaled and how it's cropped.Īn image is up scaled or down scaled when a given number of pixels in the original image is either spread out over more pixels (upscaled) or compressed into fewer pixels (downscaled) when it's displayed. You have to be careful with this term because it can mean different things depending on the context. So can someone here answer this one for me? I've never thought in detail about the term 100% crop before. This explains the difficulty in proofing a shot for sharpness on the screen. It would be GREAT to have a 100% crop detent position along the spectrum of possible magnifications. The issue is that 8x means 8x, and the K-5 is scaling that 616 pixels to stretch it to fit the 640 pixel wide screen. Using a shot of a ruler, I've measured the FoV at 8x on the K-5 display and it corresponds to a 616 pixel wide crop. So I was hopeful the 8x was Pentax's way of rounding up. The width of the K5's 4928 pixel wide images / 640 screen width = ~7.7 x magnification for a 100% crop. The 921000 is dots, R + B + G to the number of pixels is really 307,000 in a 640 x 480 screen. Its actually about 8x to get to ( wave hands wildly ) a 100% crop The K5 screen is 921000 pixels 4:3 format, or 1108*831 pixels Only a small part of the image will be displayed. If you want to show a 100% crop of the image, you must crop it, with no scaling at all. ![]() This doesn't make any real difference unless you want to scale things exactly on screen, which you might want to do with some resolution charts.ġ00% crop means that a pixel on the picture is a pixel on the screen. If you look at a range of monitors you'll see that pixel pitch tends to be around 25 - 30 microns as screens get bigger the makers put more pixels in to keep pixel pitch roughly equal. On my 26" 1929 x 1200 monitor the pixel pitch is 28.85 microns from the same maker a 22" 1680 x 1050 monitor has pixel pitch of 27.7 microns. There's another factor: monitor pixels aren't all the same size. At 100%, where 1 image pixel goes to 1 screen pixel (and sometimes called pixel-per-pixel view) a screen 1920 pixels wide will show 1920/4928 = 39% of the width of the image a screen 720 pixels wide will show only 15% of the width of the image, so you need more scrolling to see all the picture. For example, the K-5 sensor is 4928 x 3264 pixels. The number of pixels on the screen doesn't alter the definition but it does affect how much of the image you see at one go. Thank you for the replies.Īhh but, what if a person is viewing it on a 720p screen? I'm going to guess it doesn't actually lose that much info. 12M in size it lost about 99% of the data. Then I'll crop the shot to match this level and see how much this file size drops. To answer the other guy's question I think I'll make a JPEG and display it at 1:1 as you suggest. I tend to agree with this definition so lets make it official.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |