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Help with photograph, please?

I know zippity do-da about digital photography.  I understand size (sorta) as it pertains to kb vs. mb but that's not saying much.

I need this picture (353 kb) at 300 dpi.  I have no idea how to accomplish that or even where to start. 8-/  

Can someone please help me?

Picture of Help with photograph, please?
That's an odd request - print or web?

Did they specify dimensions?
bajablue (author)  killerjackalope1 year ago
The photo will be initially submitted via the web, but may go on to magazine print. After reading more fine print, I see I can submit a jpg up to 2 mb, so I'm safe.

Thanks for your time KJ.


Makes more sense, without dimensions DPI and size aren't related to each other, it could be a big image saved at a very high compression or a very small image with no compression...
download the free image program "gimp" open your photo go to "image" and select "scale image" you can change the size to what ever you want. then save as
bajablue (author)  liquidhandwash1 year ago
Thanks liquid... and congrats on your Redneck Contest win!!!
kelseymh1 year ago
Hi, Baja. Besides the operational solution already provided, it might help you in the future to have some context. There is a relationship between resolution ("dots per inch" or DPI) and file size, but it is not quite so simple for photographs.

For a simple "bit map" image, where you save each individual pixel in the file, the relationship is simple. The more pixels you want (e.g., 300 DPI for a 3x5 printed picture), the larger your file. In my example, each pixel uses three bytes, and you "want" 300*3 * 300*5 = 1.35 million pixels, so your file would be about 4 megabytes.

Obviously, that sort of method gets really large really fast (it scales with the area, not with the linear dimension). So image files are compressed in one way or another, which reduces the file size, but also makes the relationship between file and image size not so direct.

Line drawings or simple color images (like cartoons), can be saved as GIF or PNG files, which use a lossless pixel-by-pixel compression scheme. As a simple example, suppose you have a row of 150 pixels all the same color: instead of using 450 bytes, with lots of repetition you can record "150" (usually as a two-byte value) followed by the pixel color (three bytes), for a total of just five bytes and a compression ratio of 90:1. Real algorithms get fancy about compressing across rows as well, not just simple lines.

Photographs like the one you show are more complicated. Instead of giant blocks of exactly one color, they have regions where the underlying pixel colors vary smoothly. Think of a swatch of fabric with part brightly lit and part in shadow: there's a single value which "scales" a basic color code. The JPEG compression algorithm does fancy math to store parameters for such smooth variations, instead of all the pixels.

One big advantage to JPEG is that it does not have any intrinsic resolution (dots per inch). As you zoom in, instead of seeing big squares of individual pixel colors, you always see some smooth color variation, but the image gets blurry if you look too closely.

GIMP and other image handling programs (like Preview on the Mac) can read in an image in one format and save it out in a different format. Some formats have you specify a resolution (dots per inch), while others just ask for an "image quality" (how blurry are you willing to accept, in exchange for a smaller file)?
bajablue (author)  kelseymh1 year ago
lol kelsey... after reading this 3 times, the Portuguese is beginning to almost make sense!

All kidding aside, I appreciate your time.
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