I have two digital cameras. One is a 2 MP, and the other is a 5 MP. Both of these cameras download pictures that are 72 DPI. The only difference is that the 5 MP pictures are much larger. Now, I know there have been a lot of discussions about upsizing, etc., and I’m not wanting to start another big argument about the subject. What I do, and it works consistently for me, is I just crop the picture and specify the size and the resolution that I want, and then I print it. I have been very satisfied with my prints. No, I am not blind, and I have been quite critical of the work that I do.
Trish, I sometimes think that the Photoshop people built the program with inches and ppi just to drive us crazy!
Seriously, your image really doesn’t open at a certain resolution; it opens at certain pixel dimensions that are based on how it’s saved in your camera. If you have a 3 megapixel camera, your images will be something like 2000 pixels by 1500 pixels – those are your pixel dimensions in the top of the Image<Resize<Image Size box. The document size is merely a calculated set of numbers; it says, for instance that if you were to print the image whose pixels dimensions were 2000 by 1500 as a 10 inch by 7.5 inch picture (with resample unchecked), the resolution going to your printer would be 200 ppi (that’s 2000 pixels divided by 10 inches or 1500 pixels by 7.5 inches); if you changed the dimensions to 5 inches by 3.75 inches, the resolution would jump to 400 ppi. You can also substitute a ppi value; if you put in 300 ppi, the document size will change to 6.67 inches by 5 inches. In every case, the pixel dimensions of the image remain the same: 2000×1500 (so long as resample is unchecked). The initial set of values thrown in there by the program, be it 72 ppi or 300 ppi or, in the case of one of my cameras, 180 ppi, is just a starting point for that calculation of the relationship between print dimensions and resolution.
Please come back with more questions!
Chuck
Jim, your approach is solid, especially for the 5 megapixel camera. The images from that camera start with so many pixels that even if you crop and then resample (which is what happens if you specify a resolution in the crop tool), you’re probably doing very little resampling and it may be downsampling rather than upsampling – nothing wrong with that. If you were to take one of the images from the 2 MP camera, crop it significantly then upsample it to 300 ppi in one step, you might notice a softening of the printed image; but unless you’re trying to print an 8×10 or larger, the effect might not be all that noticeable. As you say, it’s giving you what you want and it’s very straightforward; no good reason to change.
Ahhh… another excellent explanation! I’ll have to make sure I keep that resample button unchecked 🙂 (Although, I am sure there are reasons why I should check it, occassionally, but I’m not sure why yet.)
Yeah, I have a 3 megapixel camera… But I take most of my images at 1 meg so I can get more on the small card that came with the camera. I will eventally buy a bigger XD card, but in the mean time I make a small sacrifice – pun intended!
So, my pictures come out at 1280 x 960. So, if PSE says it’s doing 72 ppi, then it’s going to come out 17.7(w) x 13.33(h) INCHES… but, if I bump it up to 300ppi, then it’s 4.2 x 3.2. (I left the ruler grid on to see the size changing when I was playing with this.)
So, when I upload my pictures to WALMART (cringe) for development and I ask for a 5 x 7 sized print, they are actually doing about 180 ppi on the printing? Hmmm. Would they look better if I started taking 2 or 3 megapixel pictures? I forget, but I think they have a 1 meg limit on uploads. I just picked up my last package of prints and they look pretty good, so I’m not sure if it makes any difference.
So, why to we size things width X height in PSE but when I say a 5 x 7, I’m saying height X width – at least I take most of my pics horizontally, not vertically. Or am I confused again…
I will definitely save off this great explanation as well.
Thanks Chuck!
Trish, your background in computer science and math makes you a quick study!
Yes, by all means, save everything at the highest pixel dimensions your camera will allow; 180 ppi for the 5×7 is okay, but on the low end of what would be a good printing resolution. What if you took a picture at 1 meg and then realized it was the picture of the century and you wanted an 8×10 of it, only to be disappointed with how it looked….? Look for a good price on XD cards and buy one – or two – then take all the pix at 3 MP.
Re the size convention, it seems like we always talk with the lower dimension first, regardless of whether it’s width or height. A 5 x 7 in horizontal mode isn’t called a 7 x 5 – except perhaps in the Picture Package..?
Chuck
Alright, one more question… My camera is a Fuji FinePix 3800. They have a chart that shows the setting, recorded number of pixels and the image data size:
Mode Recorded Pixels Image Data Size
3M-F 2048×1536 1300KB (approx)
3M-N 2048×1536 590KB (approx)
The manual says "Select 3M-F for better quality and 3M-N for more shots. Normally the 3M-N setting provides sufficiently high quality for printing."
If they are the same "recorded pixels" how come one is bigger than the other? What more info can they put in the image to make it over twice as big? I haven’t tried 3M-F (I’m guessing F stands for "fine" and N stands for "normal") to see what happens, but I guess I could do that. The manual says the images are all recorded as JPEGs.
Thanks,
Trish
Tricia,
It is a matter of JPG compression.
Your sensor is a 3 Mpxl device – the difference between Fine and Normal file output is how much the camera is allowed to squash the image. Because JPG does not preserve the image 100% when "re-inflated", you will have more fidelity when using lower compression.
I know it’s tempting to adjust your camera to maximize the number of images your memory can store… but you will be sacrificing image quality when you do so.
You could take some test images of the same subject in both modes and compare them so that you know what the difference is. Then you’ll make an informed decision as to how to set your camera, based on your image quality needs.
Byron
Trish, what Byron said….
Go with 3M-F ….and more memory cards.
Chuck
Whenever I decide to have my pictures printed by a photo lab I have a procedure that some may consider to be wrong, but I have had a lot of success with it. I actually do all of the sizing and color correcting before I send the images to the lab. Then I tell them not to crop at all. That way, I am able to get the pictures framed the way I want them framed. I crop the pictures to the size that I want, and then I save them at 300 PPI, and the results have been excellent. Of course I have only done up to 8x10s so far. I usually print at home if I only have a few prints to do. But if I have a significant number to print I will take them to a photo lab because it is cheaper that way.
Jim, you are right the way you do it.
But take care: don’t apply any sharpening to the images you have printed by a third party. Usually they apply a kind of rather agressive sharpening too and your image would suffer from it severely.
Leen
