#Raster graphic portable

USGS DRG data for Illinois are available free-of-charge via: an interactive map, a list of 1:24,000 scale quadrangles (1,071 files) for data download, a list of 1:100,000 scale quadrangles (51 files) for data download, and a list of 1:250,000 scale quadrangles (17 files) for data download.

#Raster graphic portable

We do not plan to distribute uncompressed data files by any other means (cd-rom, zip drives, portable drives, ftp download, etc). One uncompressed file is roughly 4 megabytes in size.Ī statewide collection of 1:24,000 scale quadrangle data requires about 2.6 Gigabytes of storage space. Just keep a backup copy before converting for any future editing of the text.Data files are offered as original USGS DRG. It’s always a good idea to convert fonts to paths (or “outlines”) to avoid this situation. 2) EPS files can still have fonts in themĪn EPS, like a logo, can contain fonts, but if a printer doesn’t have those fonts, the EPS will not print properly. For example, if a photo is placed in Illustrator and then you draw a frame around it using Illustrator’s vector drawing capability, and then you export the photo and frame as an EPS, the photo will have size limitations while the frame will not. Similarly, a raster image, like a photo, can be imported into an application such as Illustrator, but that does not magically make it a vector image. It just means there’s an EPS (Encapsulated PostScript) “container” wrapped around a picture made of dots, and the file name has “.eps” at the end. Vector images include EPSs, AIs (Adobe Illustrator native files), and SVGs.īut watch out! There are two big caveats here: 1) Not all EPSs, AIs, or SVGs are pure vectorsĪ raster image, like a photo, can be saved as an EPS, but that doesn’t magically make it infinitely scalable. A smooth circle is still a smooth circle at a million times its original size. Because vectors aren’t “images” in the normal sense but are instead the mathematical properties of lines, curves, and color fills, they can be scaled up to any size whatsoever. Vector images, however, don’t suffer from this limitation. Raster images include TIFFs, PNGs, BMPs, and JPEGs. This is why a photo that’s been blown up too much becomes “fuzzy” or “pixilated” – the computer inserts data based on surrounding dots and does a pretty poor job at it. In other words, the image’s resolution is too low for printing or on-screen purposes. If you enlarge a raster image, it will try to create data (i.e., more dots) to fill an area based on the pixels closest to it and, eventually, it just doesn’t look right. But once the graphic is enlarged, the answer becomes glaringly obvious.īecause raster images are made of dots, they can’t be enlarged or “scaled up” indefinitely. At a small size, it can be difficult to determine which of the two formats is being used. Vector images are mathematical descriptions of objects and their properties, including shape, size, position, and color.

Raster, or bitmap images, are made up of dots (color, black and white, or grayscale).

The answer is fairly simple but very important if you want your project to go smoothly.

You may have heard the terms “raster” and “vector” graphics, but wondered what the difference is between the two.