Need a little help

[DAVID Zim]

I'm using my 5D & 24-105L, and everything is fine. I sent in a few photos to a magazine and the publisher said he needs at least 300 DPI for color. How would I find that info?

Thanks,
--
David

 

[RichW]

if they insist on 300 DPI. There is no camera setting to change the default of 72 DPI. It's pretty silly because the only thing that matters is the actual number of pixels. But if they insist on 300 DPI then you have to resample in PS or other software.

Rich

 

[brooke]

I'm using my 5D & 24-105L, and everything is fine. I sent in a few
photos to a magazine and the publisher said he needs at least 300 DPI
for color. How would I find that info?

I don't understand. Maybe they don't understand. DPI is an output spec.

--
Sonoma County, CA

 

[DAVID Zim]

correct.......I have to send it them @ minimum of 300 DPI. I'm going to try the adjustment in PS tonite.
--
David

 

[DAVID Zim]

I think I have it figured out. The camera defaults to 72 DPI (shown in the EXIF data as resolution). Don't know if this can be changed in CF (I'll read the book tonight), but I do know it is adjustable in PS. Thanks RichW
--
David

 

[brooke]

... you can't give them an image at 300 DPI. AFAIK, standing on its' own, it's a meaningless spec. Any image can be 300 DPI - just print it that way. Of course, if the image is, say, 100x100 pixels, it'll be pretty small.

What you can give them is an image that's, say, 4x6 inches at 300 DPI. That image would be 1200x1800 pixels. In my (limited) experience, that's how printers/publishers request a minimum resolution.

--
Sonoma County, CA

 

[DAVID Zim]

--

--I guess that's where my stumbling block is. If I send him a file thats 4368x2912 (max res on the 5D) what does that "convert" to? How do I know if the file I'm submitting is big enough to print a 5x7 photo? Or a 8x10? etc.
David

 

[brooke]

--I guess that's where my stumbling block is. If I send him a file
thats 4368x2912 (max res on the 5D) what does that "convert" to? How
do I know if the file I'm submitting is big enough to print a 5x7
photo? Or a 8x10? etc.

First of all, give them what they want, or at least humor them. Don't tell them they don't know what they're talking about. They're the customer.

In order to know if a file is big enough, just do the math. "Dots" in DPI are pixels. 5" x 300 DPI = 1500 pixels per inch. 7" x 300 DPI (or PPI) = 2100 pixels. So the 5x7 should be 1500x2100 pixels in resolution if you want 300 DPI.

Two caveats:

1. You don't need 300 DPI for good continuous tone images. My photos have looked fine at 200.

2. It also matters at what level the jpeg is saved at. A 1500x2100 compressed to, say, 250K probably wouldn't make a good photo. I don't know the interplay between resolution and compression.

Back to your editor ... Tell them that your file will print 14.5" x 9.7" at 300 DPI. The other thing you could do is to use the Image Size dialog and - without resampling - set the resolution to 300. This will leave the pixels untouched but make the resulting output (print) size smaller. Ifmy math's right, it should then say 14.5 x 9.7 inches.

HTH (I also hope it's right).

--
Sonoma County, CA

 

[DAVID Zim]

Thank You
--
David

 

[hartcons]

The math is straightforward I think. If your image is 1500x1200 pixels then at 300dpi that works out to 5"x4" (at 200dpi that means 7.5"x6"). dpi (actually in photoshop I think it's technically called ppi although printers use dpi) is basically a way to convert from pixels to inches of printed output. if you only have enough pixels for, say, 100dpi then your print may not look as good as if you had enough pixels for 300dpi.

just make sure to uncheck the "resample" checkbox in photoshop if all you want to do is change the dpi but don't want to resize the image.

to get to a specific print size you may need to use the crop tool (for instance to generate a 5x7 when the camera image is in 3x2 format).

--I guess that's where my stumbling block is. If I send him a file
thats 4368x2912 (max res on the 5D) what does that "convert" to? How
do I know if the file I'm submitting is big enough to print a 5x7
photo? Or a 8x10? etc.