proper digital photo image size and resolution
Posted on 2011-02-25
I've got an other digital rebel 6.3MP camera. When I import the photos and see the images in a detailed view in windows explorer it tells me the dimension of the photo is 3072 x 2048. I'm trying to determine what this means for me in Photoshop.
When I do FILE > OPEN and bring in this picture it shows 17.067in x 11.378in at 180dpi at the bottom. When I bring up the IMAGE > IMAGE SIZE dialog box it tells me the Pixel Dim of 3072 x 2048 like I saw before in windows explorer and in Document Size of 17.067 x 11.378 inches at 180 dpi.
So my questions I'm trying to figure out are:
When I change Resolution to 300, the pix dim jumps up to 5120x3413 and document size stays the same because resample image is checked. Does this mean I will lose quality because it's adding pixels?
When I go back to original Image Size dialog box dimensions but this time uncheck Resize Image and put in 300 DPI the document size goes to 10.24x6.82 inches but Pix Dimensions stay. Does this mean that the MAXIMUM the pixel dimensions should ever reach using images from this camera is 3072x2048 to achieve a 300dpi quality photo for print and anything that goes over that is just adding filler pixels?
I know a camera can only output so much quality depending on the camera (in this case my 6.3MP camera) What is the maximum I can enlarge it to attain a 300dpi image.
The other reason I'm confused is because you could come at it from another way and start with a new canvas and make it 19 in x 13 in at 600 dpi and then PLACE my picture from above onto the canvas and it looks great. Can I go this big? I open Pixel Dimension and they are at 11400 x 7800 though. How do I know how much is too much in this Pixel dimension area?
Thanks for your help in understanding.