How do I change my resolution from 72 dpi to 200 dpi on my Droid Turbo camera?

[3greatcats]

I bought the Droid Turbo at the end of November. I've used the camera some, but when I opened the photos in Photoshop, they're only 72 dpi and I'd like them to be 200 dpi. How do I change that?

 

[Rukbat]

The resoution is probably the same - the same number of pixels. (If you take a 2"X2" 1080p picture and print it at 2'X2', you may start with 200dpi, but you end up with 16.7dpi. Print the same picture at 2"X2" and it's 200dpi. (If the resolution changes, either you're importing the pictures into Photoshop in some strange way, or your copy of Photoshop isn't working properly.)

There's no one-to-one correspondence between the number of pixels (the resolution) and the dpi - dpi depends, among other things, on the size you're seeing the picture at. Make it larger on the screen and the dpi goes down - for the same picture. It's still the same number of dots, but now the inches is larger, so dots/inches gets smaller - 3rd grade arithmetic. (So if you want the dpi number in Photoshop to go up, make the screen smaller. It won't do anything, but if having the number higher makes you feel better, you'll feel better.) Increasing the dpi without changing the size of the picture is ... well, it's artificial. The program will be "inventing" dots where there weren't any, so it'll be guessing what color and luminance they should be, based on the surrounding dots. It decreases the quality of the picture.

Any change in size in a picture done in a raster graphics format (GIF, JPEG, PNG, etc.) will degrade the quality of the picture. (A vector graphic file is a dot matrix, each dot being a particular color and brightness. The opposite, a vector graphic file, is a set of instructions of how to draw the picture (it's a set of vectors - "start at point A, go 2 inches at an angle of 45 degrees, painting an rgb of 255,255,0, to point B" - now you have a bright yellow 2" line going to the upper right). If you scale all the numbers down by 50%, the picture becomes 1/4 the size [1/2 times 1/2], but the quality stays the same.) If you have 10 dots and want 20 dots, you're making up 10 dots. You may guess accurately what they would have been if you had optically zoomed in twice as much, or you could be wrong. If you have 20 dots and want 10 dots, you drop every other dot and you lose detail.

Cameras use raster graphic files, because the sensor taking the picture is a dot matrix (another way of saying raster graphics), so the camera is just recording what's on the sensor. If you convert a raster graphic file to a vector graphic file first, then you can change the size any way you want, then concert it back to raster graphics. But it's a lot of work for something that probably isn't needed except in very specialized photography. (If you want to change the size of the picture, change the size - you can't change the resolution just by changing the dpi, the resolution is what it is.)

Your question is the equivalent of "how do I make a 1 pound weight weigh green?" Dpi isn't resolution, so you can't change the "resolution in dpi" any more than you can change the "weight in color".

 

[3greatcats]

Very informative! I just emailed the picture to my computer and opened it in Photoshop and checked image size. There it says the 72 pixels. And to submit pictures to a local newspaper, they ask for 200. That's why I asked if it could be changed.

 

[Sturm Rider]

While in Photoshop also check the image size. Many times you will find it is something like 41 in x 72 in @ 72 dpi. If you resize the image and do not choose resample down to about 9 x 18 it will be about 300 dpi. Which is more then enough for the newspaper.

 

[Luann Udell]

I need to save images at 300 dpi. I don't have photoshop, I use Windows Photo Gallery. When resizing, I can only select the number of dimensional pixels, and the result still at 72 dpi. Can I save an image at 300 dpi in Windows Photo Gallery? And if so, how?? (Yes, I'll try to go ask Windows too.) :^)

 

[birdpond]

Have you tried the free GIMP2 photo editing program? It's a lot like Photoshop. I use it now for my own work. You should be able to scale/resize an image to make it acceptable to your chosen site.