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Old Oct 13, 2004, 5:39 PM   #11
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Hello Everybody,
Hope not to pick a fight here but, DPI != PPI, They are similar, but different. As i understand it ppi is for monitors and dpi is for printing and other physical output. sometimes they are the same other times not, but they both are used to tell us what the final size of the output will be. 1440dpi can be 72ppi depending on the hardware involved. In this case the printer would require 20 droplets per dot rather than one pixel per well pixel. This tends to be masked from the user so as not to have to memorize every possible printer and convert.
Resolution is more a measure of how much data, whereas the DPI or PPI are of how that should be distributed. There are times when 1ppi would be more than sufficient for making a print which was beyond what a person with even exceptional skill could see. Of course such a print would be the size of the moon and cost billions, but that would be sufficient for photo quality at .25 million miles.
So to sum up: PPI is for monitors DPI is for print, and resolution only involves the size of output at a PPI/DPI.
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Old Oct 13, 2004, 9:31 PM   #12
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A quick bit of research shows you are right:
http://www.webopedia.com/TERM/p/ppi.html

My problem is that, for me, "dpi" doesn't really work for inkjet printers (which is why I dislike it.) I'm an engineer by trade and therefor I think that "dots" in "dots" per inch means a "dot" of ink... since inkjet printer heads have many really tiny nozzles that spray one "dot" of ink each. So while it's called "dots per inch", it is really the number of pixels per inch (which is translated into some number of dots depending on which printer.)

Eric
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Old Oct 14, 2004, 8:09 PM   #13
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His "better half" here-the one with the sad face over a 72,
whatever you call it. Eric, I immediately realized you were onto my problem when you said the 20D sends more info. I noticed that, but with the other cameras, it had not ever been a problem in a print. Took a picture of the cat and the straight print was awful. Upsized, and even a large cropping of just his face was looking really fine but I really didn't want even that one extra step. I will have to go about my PS work differently now, but I'm not sure exactly how. I usually do some PS work on brightening, perhaps sharpening, editing out teenage pimples, etc., then crop and print. It has always been sharp and never that "72" look with the other cameras. I was taken aback with the first print from the 20D. I use PS for editing and to run the printer - I am using an Epson 785EPX which I love, although I have to use the husband's printer for wider prints. Love everything except the cost of the ink! (Lately, I seem to be getting fewer prints out the cartridges than before.) I appreciate so much yawl's patience.
"de wife"
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Old Oct 15, 2004, 11:37 AM   #14
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Since I'm working from home, I was able to check this out.

I'm using PhotoShop CS, and under preferences->Units & Rulers I found the section "New Document Preset Resolution" it lists "Print Resolution" which I set to "300 pixels/inch", but you could set to whatever. There is also a "screen resolution" setting, but I've never touched that (it's at "300 pixels/inch".)

What I don't understand is why your other cameras set to 180, but the 20D's are coming up 72. Do you shoot raw with the others but not the 20D? (I think you said you don't.) If so this would make sense because the RAW converter ignores that setting and has its own value of what the "resolution" should be (in my case its "240 pixels/inch")

You could always make an action that resets the dpi. At least then it would be easy to change. Your work flow seems reasonable, BTW. I'm using an even older Epson Stylus Photo 700. Slow and loud but the output makes me happy. I'll eventually upgrade to a 13" printer (2200? Its replacement?) but I'm waiting a bit.

Eric
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Old Oct 16, 2004, 10:39 PM   #15
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"de wife" -Yes, Eric, that's the thing that I couldn't grasp-the 72 info for the new camera, versus the 180 for the others. No settings altered by anyone. And when the print was so poor- well, the rest is history. I haven't needed to upsize, for the cameras previously used, give me ample everything. The colors and saturations have been excellent, skintones are the envy of a friend with another well-known brand camera,so I haven't needed raw. The only time I have gone raw, was in an oddly and poorly lit gym. I had a lot of noise with the higher ISO settings on my Rebel and next game, I went RAW. Gave me only a little more latitude.
I took the 20D in today and shot some candids. My main desire for the 20D was for lower light situations-I had read the flash and metering was better. I haven't printed anything yet, but from what I can tell from the LCD and the computer, it's underexposing pretty consistantly. I do see that the picture is, as you said, BIG! So, maybe things will sharpen up and be more "resolved" when they are sized down to normal proportions. As an aside, I wonder the the odd sizes and resolutions. I'm just a do-wrong kind of person I guess, but why anyone would want to print a photo some 48" by 30-"something inches at a72 resolution?
I know from nothing, but it does seem to me to be a bizarre
kind of plot line. Why not 24 by 36 at a 180? It must be to do with restructing those pixels in the same-size sensor. Or just sheer perversity.

Husband has "CS" on his laptop and I'll look at it.
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Old Oct 18, 2004, 8:58 AM   #16
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It is my understanding that 72-DPI comes as a throwback from TVs. I don't know why it would be applied to printers, but I guess it was.

RAW won't help you too much on noise, but it will help you with those tricky lighting situations (as you say.) Adjusting white balance later is just great. Frokm what I've seen on line for scientific tests of the 10D vs. 20D for noise it looks like the noise pattern is different but not really "better" or "lower". But I haven't used one myself to test that theory.

Eric
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Old Oct 18, 2004, 9:19 PM   #17
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Eric, you are right on about the noise levels, and yes, they are a little different. I am now the proud owner of Ninja Noise or Noise Ninja--which will serve further, to complicate my life, but until the gym is renovated--I'm stuck.
I took the photos done Sat. and printed several without upsizing and, again, you were on the money with the size info. I was, indeed, stuck on that 72 resoltuion and the way I handled the photo made matters worse. The new photos, done the same way, no change in any settings--sized down to beautiful 8X10s. What I did wrong was take a test photo and I cropped it too much, giving it a true photo resolution of 72 and it looked like pooda. Simply altering my handling and keeping the crops to a reasonable size, fixed the problems.
Thanks so much for the patience and help.
Working with the settings now to maximize the inside photos.
I'm sure it can do better than I have made it do so far.
husband still clinging to his 10D!
thanks
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