smcaleer Loc: Dearborn Heights, Michigan

I'm using my new Canon 70D and I also have a Nikon D3000. I don't resize my photos. I do crop. I shoot and edit in RAW and save to jpg. Some of my jpg's save at 72 dpi some save at 300 dpi. I haven't consciously changed it to save at 72 dpi.

1. Is there a certain dpi I should save everything at?
2. What's a proper size for printing?
3. What size is good for posting online so people can see, but not be able to print for good quality?
4. And lastly, is the resize tool in PP the way to do it all the time?

Wall-E Loc: Phoenix, AZ

1) DPI has NOTHING to do with file sizes. The ONLY time it even enters the discussion, is when you're printing.

2) Whatever the printer requires. Labs will tell you.

3)Computer screens are usually in the 72 dpi range.
So, a 640x480 PIXEL image would display as 8.9 x 6.7 inches.

Now if someone was to try and print that, at a normal printer resolution of 300 dpi, then it would only give a good print to a little over 2 x 1.5 inches. Anything larger than that would start to pixelate. So, a 6x4" standard print would look like garbage.

4) I do that all the time in LightRoom and Picasa.

smcaleer Loc: Dearborn Heights, Michigan

Wall-e, thank you. Once a picture is saved at 72 dpi can it be changed to 300 dpi? I have some pictures I want to make sure I can get printed at 8 X 10 size and a few that I'd like to be able to print large enough for hanging over a sofa. I just want to make sure I can post pictures that others can't use for good prints and that I can print good quality prints.

Wall-E Loc: Phoenix, AZ

AGAIN, the DPI setting inside the image data, has NOTHING to do with file sizes, formats or ANYTHING ELSE except to confuse people.

IGNORE IT!!!



Please re-read my previous post about image sizes for posting.

My oooollllldddd D100, a 6 MP camera, makes fine prints at 20x30.

CHG_CANON Loc: the Windy City

smcaleer - you didn't mention your photo editing software. Wall-E hit all your questions. To paraphrase the technical details to address your follow-up, when you want to prepare a file for printing, return to your original RAW files and / or the edited JPEGs and prepare a specific file for printing with the highest quality and 300 DPI. I'd have to review your workflow to see if the JPEG or back to the RAW is needed. You don't want to take a smaller 'saved for the web' JPEG as the start point for printing if you have a higher quality original or edited version available.

Wahawk Loc: NE IA

Simply divide the pixel dimensions by 300 to find the maximum size for the ULTIMATE quality of print. Most prints still looks excellent when printed at 200dpi, so divide the pixel dimensions by 200 to see how big you can go.

smcaleer Loc: Dearborn Heights, Michigan

Thank you, I use PS CS6. I do save the original RAW & JPG and never work off those. I use a copy to edit. I understand better now.

smcaleer Loc: Dearborn Heights, Michigan

Thank you, this too is helpful information.

smcaleer Loc: Dearborn Heights, Michigan

Thanks again. I do understand about the dpi.

CaptainC Loc: Colorado, south of Denver

PPI

robert-photos Loc: Chicago

I disagree.

Depending on the quality of the photo an 80 ppi digital image can be decently printed without pixelation. That means that a 640 x480 pixel image can be printed as large as 8" x 6".

A table showing the minimum requirements for SmugMug prints (print labs: EZ Prints, Bay Photo, Loxley, and WHCC) and a detailed explanation can be found at:

http://help.smugmug.com/customer/portal/articles/93359

PPI (pixels per inch) is not the same as DPI (dots per inch).

sb Loc: Florida's East Coast

You will find if you look at image size in your editor that the 72 DPI images are probably much larger. I have a Sony Cybershot pocket camera which takes great quality photographs - and when I download them they are 72 dpi but the image size is 40 inches by something. There is plenty of data there to convert that (I use Photoshop Elements) to an 8x10 or even larger image with a 300 dpi resolution if I want to print.

Elements has a "Save for Web" setting which lets you save the image into a form suitable for posting - I usually save to 800 pixel width with jpg compression to medium or high (depends on what I start with) so that the resulting file size is about 100kb. This results in an image well suited for viewing on a monitor, and small enough to download quickly.

newryqs

The issue of changing your saved image to a specific resolution is, of course, not important. The setting is so your program will report back to you what your print size can be. The size of your image file is not directly related to output resolution. Big files can pixelate. A client sent me a 29 kilobyte file and wanted to make a full page image in a book. I asked for the original file to print and he contacted his photographer who no longer had the original image. Fearless to the end, the professional photographer just put the image into Photoshop and resampled the image up to 5 megabytes and sent it back to his client! Garbage in - garbage out. The only improvement was that the huge pixels didn't pixelate, themselves. Resmpling an image upwards does not give you the missing detail. Fortunately, the original image was eventually found. As stated, an image saved at a particular setting is not important. If you have kept the original detail, the image file will print to the best quality possible from the original conditions. Always save the original image, immediately, in a lossless format: tif, raw, png, etc. and then you can convert to jpg if necessary. Converting from a jpg to a tif, is too late, some original data are gone. Editing a jpg looses data every time there is a new save that replaces the old file. Editing in lossless formats keeps the image at its highest quality. The only reason to use jpg is for the requirements of the final output device. Note: Actual file sizes in megabytes are not directly related to the resolution you can get. Files sizes are merely indicative of how many data are present. Equal size files may have very different print size vs resolution capabilities. Yes, if you have low standards, you might be able to print almost any file, but if image quality is important to you, you will do everything you can to protect the original pixels.

smcaleer Loc: Dearborn Heights, Michigan

Thank you. I have not seen a "Save for Web" in CS6 (although that doesn't mean it's not there), but I will look for it.

smcaleer Loc: Dearborn Heights, Michigan

Thank you. I do always save the original RAW. I only set my camera to make the jpg incase I need something immediately and can't get to a computer with an editor. Other than that, I typically don't even use the jpg out of the camera. I'm still working on a storage/filing system that works for me. I think I'm almost there. I just don't want to save useless files, but want to make sure I save what I should.