How do you deal with the "DPI" question? (graphic artist)

Situation:

• customer gets processed pictures (jpegs)
  
• DPI doesn't really mean anything and is still set to 72 dpi from the camera
  
• customer gives pictures to graphic artist for making e.g. invitations
  
• text coming back to me from artist through customer: "these pictures are too low resolution. I can scale them up but then it would look ugly. Can you ask the photographer to provide higher resolution? The stuff he gave you is for the inter net" (not my space)
  
• I edit the DPI field to 300 or 600 or 666 or most-positive-fixnum or something and send the same picture in the same resolution back
  
• everyone is happy (except me)
  

I set the ppi to 250-300 when I export them, even though it makes no difference. If asked I explain the concept to people.

Don't bother to argue with the artist unless you're going to be doing a lot of work for that client. It's just not worth the aggravation.

I recently had a similar scenario with a magazine editor. She disliked the "low res" image I sent her for the cover of her A5 magazine. This "low res" had made a nice A3+ print so was actually pretty high res, but from a 30D.

All I did was artificially whack in more pixels and sent it back to her. Now shes a happy bunny, but the reality is its no better than it was before.

People who have a little knowledge are the worst.

MAC users!!!
How can you learn what your equipement does if everything works perfectly all the time.(This is funny so laugh)
Does photoshop on the MAC not resize?
If you just type in 240ppi the image just resizes with no information loss.

Or maybe this is a manifestation of the dividing line between the Artist and the Scientist

Well...

I'll just try drinking more then

uOpt wrote in post #14452388
Situation:

• I edit the DPI field to 300 or 600 or 666 or most-positive-fixnum or something and send the same picture in the same resolution back
  
• everyone is happy (except me).

IF the image is to be printed via the offset press (not a light-sensitive photographic printer, not a inkjet), the DPI count can indeed matter!

So with that understanding, simply assume that no one has told you that the image is to be offset print, embed the '300' within the EXIF file. And go away happy in the knowledge that you provided a suitable file -- even if the image is not ultimately reproduced via offset printing, it works!

PS: Since we know this is to be used by a graphic artist, AND because we know this is for making inviations, we can suspect that an offset print might be involved, so '300' value might be something that the PRINTER has to have (because their software for manipulating digital files assumes 300 dpi and because the printer staff is too lazy or uninformed to know that they can set this value regardless of what is in the supplied file)

Wilt wrote in post #14454844
[/LIST]IF the image is to be printed via the offset press (not a light-sensitive photographic printer, not a inkjet), the DPI count can indeed matter!

So with that understanding, simply assume that no one has told you that the image is to be offset print, embed the '300' within the EXIF file. And go away happy in the knowledge that you provided a suitable file -- even if the image is not ultimately reproduced via offset printing, it works!

But if the printer need that 300 DPI value, wouldn't the printer take that to mean how large to project the photo onto the paper? So an image that is 900x900 pixel gets printed as 3x3" if 300 DPI and 6x6" if it has 150 DPI?

In the end, that graphical artist has to play around to specify the actual scaling of the photo to fit the intended layout - so why would a specific printer technology need a sepcific DPI value for a photo that the graphical designer want to print with a completely different magnification?

pwm2 wrote in post #14455190
But if the printer need that 300 DPI value, wouldn't the printer take that to mean how large to project the photo onto the paper? So an image that is 900x900 pixel gets printed as 3x3" if 300 DPI and 6x6" if it has 150 DPI?

In the end, that graphical artist has to play around to specify the actual scaling of the photo to fit the intended layout - so why would a specific printer technology need a sepcific DPI value for a photo that the graphical designer want to print with a completely different magnification?

The offset print industry used 'dots' many decades before 'pixels in digital images' were invented! 'dpi' is 'dots per inch', not 'pixels per inch'.
If you look very closely at newsprint, you will see that images are grayscale images produced with half-tone dot matrices, there are no intermediate gray ink dots, only black dots of different densities per area. So in the past a glossy print was provided to the printer and they used half-tone screens to turn the image into a bunch of dots...the higher the number of dots, the more tonal differences could be recreated with black ink dots. In newsprint we might use only about 85 dot screens, in glossy paper magazines we might use 150 dpi, both to print a 4x6" image area on the printed page.

The confusion arises now because many vendors of software all too freely intermix the concepts of 'ppi' and 'dpi'', when in fact they are two different concepts. Yes, changing 'pixels per inch' changes size on the page. Changing the dot screen does not alter size, it only alters the quality of reproduction of colors and shades of gray.

And that is the reason why we can take the identical 2000x3000 pixel image file, print it to 8x12" and also to 4xx6" final size, using either a Lexmark P315 4800 x 1200 dpi Photo Printer and also to a Lexmark C792DTE 2400 x 600 dpi color Laser Printer. Today DPI is an output device specification, like it was with offset print resolution decades ago, and has no relationship to size!

There is a big confusion between DPI and PPI (Pixels per Inch).

But is the DPI field in the EXIF data dots per inch for how the printer should create shades, or is it pixels per inch for intended magnification of a print?

pwm2 wrote in post #14455330
There is a big confusion between DPI and PPI (Pixels per Inch).

But is the DPI field in the EXIF data dots per inch for how the printer should create shades, or is it pixels per inch for intended magnification of a print?

I have printed an image to my printer with the original value '72' in the EXIF, then used an EXIF editor to change that value to '300'...printed both on my Canon iP4000 which has output of 4800 dpi x 1200 dpi, and there was NO OBSERVABLE difference in the output prints.
What would happen if I had sent both files to an offset printer is not determined.

But the picture won't be sent to the printer directly.

The picture gets embedded with a DTP program or whatever they are using at the graphic artist's place.

When you're dealing with a graphics program, the ppi/dpi tag has an affect. For example, if you open a New document in Photoshop or, say, Microsoft Word, and place an image on it the image will display/"show up" using its dpi/ppi, related to the display size and dpi/ppi of the "background" document. You can, of course, resize the image after it's in the document to "fit" the desired view, but I imagine that people on the editing size want the image ppi to fit the dpi of the document to save them having to mess with it.

I'm not in the graphics art field, so that's just the one viewpoint I have, and I may be technically "all wet"...

When my final deliverable is a digital file, I just have Lightroom set that field to 300DPI upon export, unless the recipient can give me a valid reason to change it to something else. If the recipient has only a little knowledge, they'll see that 300 DPI in the metadata, and they'll know my work is top quality. If the recipient has more than a little knowledge, I'll ask them what pixel dimension they need.


... but I guess my work is only half as good as the guy that sets it to 600 DPI

nathancarter wrote in post #14463985
...they'll see that 300 DPI in the metadata, and they'll know my work is top quality. ....

Good strategy! I've had a few things printed at a local shop, and I always make sure the metadata includes the "proper" dpi and print size. First time I took something in the lady who operates the printer (they use a wide-carriage Epson Pro 9500 and print from PS Elements) pulled up my file, saw that it said "16x20, 300 dpi" in the metadata, and said "Oh, wow, you really know what you're doing. What a pleasure!"