I think my Design for Print teacher is an idiot

[Transient]

Alright, he knows everything there is to know about printing, but his intelligence stops right there as far as the printing press goes. As soon as everything moved over to computers (read: Photoshop, Quark/InDesign, etc.) he got lost. I swear he makes up some of this stuff as he goes along. But before I call him on something, I want to be sure.

Today he was explaining resolution, dots per inch, lines per inch, and monitor displays. He said that he preferred viewing websites that were designed with images that were 85dpi or even 100dpi rather than 72dpi, but to my knowledge, that's not how images work when viewed on a monitor. Isn't dpi only used to measure resolution when printing?

I tried to get him to elaborate, because at first I was confused and not sure WTF he was talking about, but he shrugged the question off and changed the topic.

Oh, and he tried to show us how to save something in ImageReady in order to reduce the filesize, relating it to an earlier lesson about image resampling, but I called him on it and explained that it was because the default filetype of ImageReady was .gif and had nothing to do with the program. I wish he'd stop bullshitting us and take a summer seminar or something to get a clue before he teaches this class again...

[plained]

the b ook says

[Nightshade]

Is it an Intelligent Design for Print class?

[R00k]

Hey, those who can't do, teach!



(j/k tnf )

[seremtan]

i'd be happy to help out if only i knew what the answer was

[Canis]

I think 72dpi is just what's represented on your screen. So I believe if you were to take a screenshot and then print it, you'd print out (at regarless of the print resolution) 72 of the screenshot pixels per inch on the paper.

[brisk]

Heh, half of my design tutors don't have a clue when it comes to design technology either. And yes, they're the ones 40+

[R00k]

72dpi is the quality of the medium that the picture is displayed on, isn't it?

i.e. a 72 dpi printer will print 72 dots per inch on paper; or a 72 dpi monitor will display 72 dots per inch on-screen.

I'm not a connoisseur like Toxic, but I don't believe that is a function of the image itself. Image quality is measured in pixels/resolution/color quality, isn't it?

[HM-PuFFNSTuFF]

72dpi is the quality of the medium that the picture is displayed on, isn't it?

i.e. a 72 dpi printer will print 72 dots per inch on paper; or a 72 dpi monitor will display 72 dots per inch on-screen.

I'm not a connoisseur like Toxic, but I don't believe that is a function of the image itself. Image quality is measured in pixels/resolution/color quality, isn't it?

ding we have a weiner!

[Canis]

72dpi is the quality of the medium that the picture is displayed on, isn't it?

i.e. a 72 dpi printer will print 72 dots per inch on paper; or a 72 dpi monitor will display 72 dots per inch on-screen.

I'm not a connoisseur like Toxic, but I don't believe that is a function of the image itself. Image quality is measured in pixels/resolution/color quality, isn't it?

Because a 72dpi monitor can display at different resolutions (up to 1600x1200) in the same area, I'd think that then increases the "dpi" of the monitor even though the image resolution sent to the monitor is 72dpi. I think the desktop image is sent out at 72pdi, even though its displayed at a higher resolution. That's why icons and such get smaller at higher resolutions. Still, if you print out an icon, regardless of your screen resolution you'll still get the same sized image from your printer.

[HM-PuFFNSTuFF]

Isn't dpi only used to measure resolution when printing?

I

no dpi is also used for screen pixel resolution (although technically it should be ppi, everyone says dpi)

[R00k]

72dpi is the quality of the medium that the picture is displayed on, isn't it?

i.e. a 72 dpi printer will print 72 dots per inch on paper; or a 72 dpi monitor will display 72 dots per inch on-screen.

I'm not a connoisseur like Toxic, but I don't believe that is a function of the image itself. Image quality is measured in pixels/resolution/color quality, isn't it?

Because a 72dpi monitor can display at different resolutions (up to 1600x1200) in the same area, I'd think that then increases the "dpi" of the monitor even though the image resolution sent to the monitor is 72dpi. I think the desktop image is sent out at 72pdi, even though its displayed at a higher resolution. That's why icons and such get smaller at higher resolutions. Still, if you print out an icon, regardless of your screen resolution you'll still get the same sized image from your printer.

I think dpi is more of a spec for monitors, instead of a configuration setting. Like "This monitor is capable of displaying images at 72 dpi."
Even if your video card is only outputting 800x600 pixels on a 20-inch monitor, the monitor display quality is capable of higher.

But the quality of an image itself is not dependent on a dpi setting - unless you want to go through the abacus-style of judging quality, and divide the number of pixels in an image on each axis by the length of the picture on that axis.

Basically, a small picture will be of higher image quality than a larger picture with the same number of pixels, if everything else about it is the same - hence, a greater number of pixels per inch. It's the reason you lose quality when you enlarge something.

But then, a 100 dpi image with 16 colors still looks like shit, so it's not much of a yardstick by itself, and not the way to really describe image quality.

[Canis]

Yeah, its funny how folks resort to image quality as being only dpi-related. There's the bit depth, compression, color profile, etc. I guess I was just going on the size of the thing, and what it means when an image of a certain dpi is presented at another resolution. Its odd when they have a 1200dpi image being sent to the screen at 72dpi and displayed at a screen resolution of 1600x1200dpi, but then printed at a resolution of 600dpi.

[tnf]

Hey, those who can't do, teach!



(j/k tnf )

And those who can't teach become principals and superintendants...

[emoticon]

Hey, those who can't do, teach!



(j/k tnf )

And those who can't teach become principals and superintendants...

And those who can't become principals and superintendents uhm...uhm...go back to school. The circle is now complete and the cycle begins again.

[netrex]

Sounds like crap to me. If you're not gonna print the images you work on, e.g. you're only using them on a website, the only thing that would matter when it comes to size is the resolution of them. Of course the DPI you see them as depends on the size of your monitor and what resolution you run. AFAIK, the DPI only change how it looks when printed, right?

It's simple to test. Make to images with the same width and height and only change their DPI, then look at them on a monitor and they're the same size. Print them and they're different. Test him with those pictures and see if he can pic out the 72DPI image over the 85 or 100DPI image when shown on screen.

[Geebs]

It's simple to test. Make to images with the same width and height and only change their DPI, then look at them on a monitor and they're the same size. Print them and they're different. Test him with those pictures and see if he can pic out the 72DPI image over the 85 or 100DPI image when shown on screen.

Presmably, though, there's a different ratio for resampling if you want to display those different images on a monitor, one of which will be optimal?

[netrex]

That might be. Kinda like watching DVDs. They can have the same size in pixels but vary in aspect ratio. Didn't think that applied to who picture files were displayed. But on a website you set pixelsize in the HTML or CSS, so I would thing that pixel size matters more there than DPI. Maybe in software used for stuff that will be printed, a different way of calculating the size on the monitor is used?

[MKJ]

rook is oh so right
monitors show everything at 72dpi (sometimes 96).
if you make a picture at 72dpi at say 10 inch width in photoshop, and then resample it to 300dpi itll show up as a huge pic on your screen. print it and itll still be 10 inch wide.
its bigger on the screen @ 300dpi than at 72 dpi simply because your screen wont resample, just the image

[MKJ]

and i fucking hate people who open up an image in ImageReady and just click "save for web", and assume its all done.
the other day i saw this huge banner with all kinds of pictures and text and gradients and shit which was saved as a gif. fucking 77k. youd get the same quality in a 30k jpg fcol

[Ryoki]

I had a prof tell me that the key to make people return to websites is applications rather than content yesterday. I thought maybe he was joking at first, or perhaps testing out his audience to see if we were paying attention, but then he started to explain how '....back in the early days of the internet, in 1996...' and i realized the poor man was probably just an idiot.

[Transient]

Cheers guys. I'm going to wait for him to mention website dpi again and call him on it in front of class. I've already done this before in another class I've had with him and know how he'll react, but knowing the students in this class, the reception should be... interesting.

[Geebs]

rook is oh so right
monitors show everything at 72dpi (sometimes 96).

If that's the case, how come a 15" laptop monitor can be 1152x768, 1280x820, 1440x960, etc, eh?