confused about file format

[mangcang]

Hey, guys

If I place an EPS image and a JEPG image or other file format images in one document in indesign, and then I export it to EPS from Indesign. I am wondering what happen to these images inside? Do they become all EPS files? or? what is the relationship between the new EPS file (came from indesign )and other image format inside? So confused~

 

[pdan]

Other than "that's the way it's been done forever", is there a reason you would export to eps? Export pdf from ID

eps is outdated and removes many features you would want maintained for consistant reproduction and exchange.
"Do they become eps files?" - if you are wondering, does the jpg become a vector image, no.

I'm far from fluent as to the specifics, and may put my foot in my mouth, but for the sake of your question;
eps = encapsulated postscript. Encapsulated referring to all within one wrapper. Think of this as a grouped object which can contain points, paths, raster date, color data, size, fonts. The application eps is placed into does not need to/cannot manipulate the "group", but merely pass the data to the imaging device.
Postscript = The language used for imaging

eps does not support multiple pages, color profiles, and "rich feature content" not necessary for putting ink on paper that current documents might have. ie: bookmarks & links, buttons and interactive elements...

 

[mangcang]

Other than "that's the way it's been done forever", is there a reason you would export to eps? Export pdf from ID

eps is outdated and removes many features you would want maintained for consistant reproduction and exchange.
"Do they become eps files?" - if you are wondering, does the jpg become a vector image, no.

I'm far from fluent as to the specifics, and may put my foot in my mouth, but for the sake of your question;
eps = encapsulated postscript. Encapsulated referring to all within one wrapper. Think of this as a grouped object which can contain points, paths, raster date, color data, size, fonts. The application eps is placed into does not need to/cannot manipulate the "group", but merely pass the data to the imaging device.
Postscript = The language used for imaging

eps does not support multiple pages, color profiles, and "rich feature content" not necessary for putting ink on paper that current documents might have. ie: bookmarks & links, buttons and interactive elements...

Thanks Pdan；-）another question. If I create a pdf from indesign, does that pdf remain the effective ppi of raster images and infinite resolution of vector images individually?

 

[Stephen Marsh]

Thanks Pdan；-）another question. If I create a pdf from indesign, does that pdf remain the effective ppi of raster images and infinite resolution of vector images individually?

Depends on the PDF export settings. Most "out of the box" PDF export settings are set to resample the image to say 300ppi if it is over say 450ppi (or whatever the value may be). One can alter the PDF output options to turn resampling off and to use lossless compression over the default lossy compression. Vectors are retained as vectors - except if transparency flattening forces the vectors into rasters (.ps and .eps have the same issue, they are always flattened while with PDF one can elect not to flatten transparency).


Stephen Marsh

 

[mangcang]

Depends on the PDF export settings. Most "out of the box" PDF export settings are set to resample the image to say 300ppi if it is over say 450ppi (or whatever the value may be). One can alter the PDF output options to turn resampling off and to use lossless compression over the default lossy compression. Vectors are retained as vectors - except if transparency flattening forces the vectors into rasters (.ps and .eps have the same issue, they are always flattened while with PDF one can elect not to flatten transparency).


Stephen Marsh

Thanks and really appreciate your replies.

 

[mattbeals]

As PDAN and Steven said, EPS is dead. No one has buried it yet. InDesign will take what you have and if you export it as PDF put all of the contents in a PDF "container" of sorts. Raster EPS's become raster images, JPEG's stay as raster images, vector graphics stay vector, type stays as live type (with a few exceptions including the note regarding transparency).

PDF is a much more flexible format. You'll be happy that you stopped using EPS.

 

[GuruMorgor]

So if EPS is dead, what do you guys do when you get a 72dpi RGB logo pulled from the web and are asked to put it on a billboard or the side of a semi-truck hauler? Is there a process for taking a small raster image and making it huge with no loss of quality?

 

[buckeye]

EPS format has nothing to do with a file being 72dpi or RGB. And there is no process in the world that will allow you to take a 72dpi image and put it up on a billboard or anything like it.

-Erik

 

[Lammy]

The confusion I think comes from the ability of a vector file and an raster file to both be an .eps file. In this case the file format does not define if the file is infinitely scalable or not but it's content does. The same essentially holds true for .pdf, .ps and a whole host of other file formats.

This is why I have changed to telling customers "I need a vector format file LIKE and eps, illustrator or corel file". Inevitably I still have the ones that will just re-save their .jpg to a .eps, or better yet place the .jpg into illustrator and save a .ai file, then act all confused when I tell them this is no better. At least asking for a "vector" I can go back and say "yes it is an .eps now, but it's still not a vector."

 

[GuruMorgor]

Well put Lammy, you said the magic words - infinite scalability. I get to explain this to our clients at least once a week, the whole raster/vector explanation, the RGB on screen vs CMYK on paper (why my colors bad?) explanation and many other things our clients are unaware of. My point is that eps is alive and well in my workflow, Can you do a clipping path in photoshop and not save it as an eps now? I am biased as I use adobe programs almost exclusively and I'm sure Corel probably has a format much like eps. PDF workflow is getting better, I will admit, but for now I'll stick with EPS when working with vector files

 

[Visualaid]

So if EPS is dead, what do you guys do when you get a 72dpi RGB logo pulled from the web and are asked to put it on a billboard or the side of a semi-truck hauler? Is there a process for taking a small raster image and making it huge with no loss of quality?

use your illustrator skills and rebuild it.

 

[Stephen Marsh]

Is there a process for taking a small raster image and making it huge with no loss of quality?

To retain the original low resolution "quality" and make it "huge with no loss of quality" - one would use nearest neighbour interpolation with a value such as 200% / 600% / 800% etc. There is no free lunch for an unrealistic request such as you mention. The result looks just as poor as the original, just at a larger size! :] Other interpolation methods will tend to anti-alias and reduce the original "quality".

As mentioned in the reply above from Visualaid, one would have to redraw the image in vector format (manually, auto trace).

There are some good third party raster resizing programs, however they are generally good to rescale 200-800% size and they generally work much better on logos and text than Photoshop resampling methods.


Stephen Marsh

 

[Amer]

Well put Lammy, you said the magic words - infinite scalability. I get to explain this to our clients at least once a week, the whole raster/vector explanation, the RGB on screen vs CMYK on paper (why my colors bad?) explanation and many other things our clients are unaware of. My point is that eps is alive and well in my workflow, Can you do a clipping path in photoshop and not save it as an eps now? I am biased as I use adobe programs almost exclusively and I'm sure Corel probably has a format much like eps. PDF workflow is getting better, I will admit, but for now I'll stick with EPS when working with vector files

You can save a clipping path from Photoshop in both PSD and TIFF and InDesign will be able to use it. I quit using EPS when CS2 started supporting duotones in PSD.