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#EPS file output

13 messages in this thread
#152498From: Michael E BartlettFeb 11, 1995 10:10 PM
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?
#152499From: Jonas Ruikis [ADESK]Feb 11, 1995 10:25 PM
<< Can you folks shine a little light on this for me? >> I'll have the developer of the routine review your post.
#152584From: John SchmidtFeb 12, 1995 12:23 PM
PhotoStyler, (at least ver 2.0), also doesn't recognize 3DS EPS output. But WordPerfect Win/6.0a and AutoCAD R12/Win both read it in just fine. Unfortunately, PhotoStyler and PhotoShop are the two programs I'd *most* like EPS to work with.
#153585From: SyndesisFeb 16, 1995 1:44 PM
Not all EPS files can load into PhotoShop or PhotoStyler. PhotoShop can read EPS bitmap files that it saved itself, and I'd guess that they made PhotoStyler handle that variant of EPS, too. The EPS standard is nothing more than a few conventions for some very minimal comments at the head of the file that document the clip art's size on the page, which fonts it might use, etc. Within the EPS file, you can have almost any series of PostScript commands. This sort of confusion also happens with Adobe Illustrator files, too. AI saves its own drawings in EPS-like files. You can save an AI drawing as EPS and load it back into AI just fine, but AI can't read any EPS file, it can only read the ones that happen to format their PostScript commands in the same way that AI does. In theory, Autodesk could write EPS files that conform to PhotoShop's method of saving EPS bitmaps. But why bother? Just use some other standard bitmap format that PhotoShop can load instead.
#153699From: John SchmidtFeb 16, 1995 9:50 PM
John, >> Just use some other standard bitmap format that PhotoShop can load instead. Yea; that's what I do. I was just commenting on it as a curiosity. John
#152793From: Brian Rudolph [Adesk]Feb 13, 1995 12:08 PM
EPS output from 3D Studio is designed to be brought into a document layout program. When you are bringing images into image processing programs, like Photoshop or Photostyler, you will do much better to import a truecolor TIFF or TGA image. Also, Adobe EPS files are rather unique in the postscript world and (as you found out) not all EPS file can be read by those programs. -Brian
#152816From: Jonas Ruikis [ADESK]Feb 13, 1995 1:11 PM
Hi Michael, The developer had the following thoughts to share.. "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." and.. "Again, I would think that PhotoStyler also should not be a problem since it reads many image file formats. Maybe you could ask him what advantage he sees in producing EPS for import into these programs instead of some other image format. After all EPS does not support compression so he can get smaller files via other means."
#153005From: Michael E BartlettFeb 14, 1995 12:21 AM
Jonas and Brian, 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. >> My guess is that the person misunderstands how it works. 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. … Still awaiting enlightenment. Michael B.
#153142From: Jonas Ruikis [ADESK]Feb 14, 1995 4:00 PM
Hi Michael, from the developer… "> 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."
#153238From: Michael E BartlettFeb 14, 1995 11:25 PM
Developer, Thanks for the discussion of image size, page size, and the relationships of pixel resolution and DPI. That does help clear up the issue somewhat. Too bad it is not more thoroughly discussed in the documentation. Can you explain why these files cannot be reviewed in Photoshop? Michael B.
#153262From: Jonas Ruikis [ADESK]Feb 15, 1995 1:28 AM
Hi Michael, Well.. the previous post said, " 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." Maybe PhotoShop tech support can answer this one? I truely don't know. Sorry. jonas[adesk]
#153333From: Brian Rudolph [Adesk]Feb 15, 1995 11:46 AM
<<Can you explain why these files cannot be reviewed in Photoshop?>> the bottom line is Adobe EPS files are a different flavor than a generic EPS file. The files themselves have header information that needs to be in a specific order, and misc. information that is not needed for other EPS files. Most packages that support Adobe Photoshop and the like, don't just claim EPS support, but Adobe EPS compatability. -Brian
#153428From: Michael E BartlettFeb 15, 1995 8:59 PM
OK, Brian, Jonas, Thanks for the clarification. Everybody seems to have turf to protect, hence sticky tricky file format specifications for Adobe EPS files. Anyway, it is good to be able to output EPS files from 3DS. It is great to have such good support for these questions. Michael B.