#3DS EPS out to Photosho
23-Aug-95 11:30:16
Sb: #186782-#3DS EPS out to Photosho
Fm: Jonas Ruikis [ADESK] 73172,1351
To: David J. Marks 72172,1036
Hi David,
<< EPS and 3DS4… >>
Here's all of the relevant posts that I could find..
> The R4 manual implies that the EPS file format output is compatible with
> the Adobe Systems language description. However, the EPS files I have
> produced from 3DS are not readable by Adobe Photoshop. I have also found
> that the IPAS routine that is supposed to configure the EPS output from the
> renderer ignores the image size and DPI input producing instead images of
> another size and specification.
>
> I have followed the instructions in the manual explicitly. Can you folks
> shine a little light on this for me?
>
> Michael Bartlett – AEtherium Visions
Jonas,
The EPS that we produce does indeed meet the Adobe specification, however,
Adobe Photoshop requires a very specialized version of EPS to read. This
should not be a problem, because Photoshop can read a lot of image file formats
that are supported by 3DS. I would recommend either TIFF or TARGA (since they
both support 24 bit formats).
Just for your background, EPS output makes more sense either for printing
directly or for bringing into page layout programs that may not support image
formats.
Finally, regarding the last point I am unaware of any problems with setting
the size. My guess is that the person misunderstands how it works. Anyway
more info is required before the last problem (size and DPI) can be addressed.
Keith
———————————-
> It is understood that EPS output is for the use of Postscript hardcopy
> output. The question you are asking is why would anyone want to bring an
> EPS file into an image editing program? The idea is to check the image
> prior to printing. Of course a targa or tiff file can be loaded in
> Photoshop, that's not the point.
>
> The point is that if the EPS output is ADOBE compatible then I should be
> able to open it in ADOBE software. Especially, Photoshop. If it won't
> then it isn't compatible.
The EPS file format is spelled out in detail in Appendix H of the second
edition of "PostScript Language Reference Manual" by Adobe Systems Incorporated
also knows as the "red book". A brief quote from that section may be of
some use. From page 709 "An encapsulated PostScript file is a PostScript
language program describing the appearance of a single page. Typically,
the purpose of the EPS file is to be included, or "encapsulated", in another
PostScript language page description. The EPS file can contain any combination
of text, graphics, and images, and it is the same as any other PostScript
language page description with only a few restrictions."
The EPS file produced by 3DS R4 is fully compatible with that format.
However, Adobe PhotoShop does not claim to be able to import any EPS file and
in fact it can not in general read other programs' EPS files. It would in fact
have to have an entire PostScript interpreter to do so as implied by the above
description of what an EPS file is.
> As for the DPI/image size issue. It is a well documented fact that the R4
> manual is less than completely lucid in many areas. Try it. Render an
> 8×10 image at 150 DPI and see what you get. The result will be relative to
> the resolution of the render image setting, but not the size specified in
> the EPS configuration dialogue. This is immediately apparent when the image
> is brought into a DTP program like Quark Express. Perhaps "the person
> misunderstands" something that is not apparently well documented. …
Perhaps the description in the reference manual is not clear. Let me attempt
to explain. On page 59 of "3D Studio New Features" manual it says that the
page size "sets the width and height of the output on which the output image
is centered." Note this is the size of the output page, NOT the image.
Also on page 59, the resolution setting is described as "sets the resolution
in dots per inch or millimeter … The larger the resolution value, the
higher the quality of the image, but the smaller the resulting size." This
may seem a somewhat strange way to control the size, but is driven by the
way plug-ins interface to 3DS. A BXP plug-in, such as the EPS plug-in, can
not control the size of the image in pixels. The user must do this via the
Renderer/Setup/Configure menu.
So, in the case described above the user runs the EPS PXP and specifies
150 dpi and whatever page size they want the image centered on and in the
Render/Setup/Configure menu set a width of 1200 (8 inches times 150 dpi) and a
height of 1500 (10 inches times 150 dpi) and then render the output.
Hopefully this clears up the confusion.
——————————————————-
Here is plenty of info on the thoughts and means of EPS out from 3DS.
1. EPS was first developed on the MAC. On the Mac, every file has a resource
fork. In the case of EPS, the resource fork contained a PICT of the image. Thus
if you tried to read it into a graphics program, it would read the resource
info, and produce an image. If you printed it, it would bypass the resource
info, and go straight to the EPS data.
On the PC, there is no Resource Fork. So an EPS file is really 2 files combined
into one. The first part of the file (if it is included) is a TIFF
representation of the EPS image. Thus a program will read the TIFF file part of
the image, and put the graphic on the screen when you use the image in your
program. Or when you print, it bypasses the included TIFF file, and sends the
EPS DATA directly to the printer.
Include Preview is an option in the EPS out module. If Customers are saying
they
don't see an image, but instead just see dotted lines or a grey box, they most
likely did not configure to include the Preview image. The program is instead
looking at the comments data, reading the dimensions of the image only, and
then
just displaying a box with the proper dimensions
2. If they say they can't read in the EPS file, are they using a MAC or PC
version of their software? The EPS file is NOT a cross platform file, even
though it exists on both platforms, for the reasons above.
3. Keith, who wrote the EPS out module, tested it with QUARK and Word for
Windows. Worked in both of those programs. David Ang and QA tested in others,
don't have the list.
4. Notice that those programs above are PAGE LAYOUT programs, not image
processing programs. The philosophy behind EPS out is that you would use this
feature in Page Layout programs. Thus you would see a representation of the
image (the included TIFF file) when working on the computer, and when printing
you would print from the EPS data. EPS files are not intended to be brought
into
image processing programs, like Photoshop. For those applications it is
expected
that the user will bring in a 24 bit TIFF or TGA file directly.
5. In the specific case of ADOBE Photoshop or ADOBE Illustrator, the EPS file
is
unique. Adobe Photoshop is specifically looking for an Adobe EPS file. This
file
will have unique preview, comment data, and EPS data with special formatting.
We
do not produce EPS files that are compatible, users should be importing TGA or
TIFF files.
-Brian