CompuServe Thread

#3ds ratio

11 messages in this thread
#6603From: sherwood egbertDec 11, 1991 5:32 PM
kevin, what would the aspect ratio be for a 4096×4096 targa file in 3dstudio? thanks
#6611From: Yost GroupDec 11, 1991 7:31 PM
Sherwood, depending upon how much free hard disk space you have on your 3ds disk partition, plus RAM, a 4Kx4K file could take alot of memory to render. For example, without a rescaled background, it would take over 64 Megabytes… up to 80 Megabytes with some geometry and a small shadow map… 140 Megabytes with a rescaled background, etc etc. We've gotten tremendous results with high antialiasing on 2K images. In fact, the current cover of Cadalyst magazine (December issue with the bowl of fractal soup), is done in 3DS at 2048×1536. You should pick up a copy; it's one of the best computer graphics covers I've ever seen. (it's just hitting the stores late this week) If you haven't read 3DSRAM.DOC in DL9, check it out. – G PS: The aspect ratio for imaging to film is almost always 1.0, no matter what the output resolution. 2048×1536 is the most common 35mm slide output res.
#6637From: sherwood egbertDec 12, 1991 9:58 AM
thanks Gary , i will try the 2k targa first and see what imageset can do with it sherwood
#6651From: doug wolfgramDec 12, 1991 12:28 PM
Sherwood, you might also check COlossal Graphics in San Jose or Master Blueprint in Minneapolis I believe. I have had several of Brett's (our fine artist) images printed via Versatec electrostatic plotter and they are quite nice, but the colors aren't as rich as a photo would be naturally. I am looking for a list of large-format-targa-printing houses. Could you give me some details on Imageset? Thanks…
#6654From: sherwood egbertDec 12, 1991 1:04 PM
sure, i talked to them yesterday and they were quite friendly and knowledgeable about the process that it takes to print a targa file photorealistic. they are located in san fran. (415-626-8366) they are going to take my targa file on tape and color process it to a 4×5 neg and a 35 mil slide. they like to use both because the 35 mil slide gives the print shop a reference as to how the final print should look. since this is my first time in doing this kind of thing i'm looking forward to seeing the results. there is another company that is called iris graphics that i hear can take a targa directly and print out a large 24×36 inch print. but im not sure what they use. i think brilliant image in new york is installing one of these in january. sherwood
#6671From: doug wolfgramDec 12, 1991 8:27 PM
My wife and I are planning a high-end computer fine arts business and are looking for a reliable output center. I will check them all out… Thanks
#6648From: Noah KennedyDec 12, 1991 11:42 AM
Gary- Why is 2048×1536 a "common" slide resolution? I'm surprised that this represents a 4:3 ratio. I thought 35mm was 3:2. –Noah
#6661From: Yost GroupDec 12, 1991 5:10 PM
Good question… I don't know why, but this is the resolution that all the slide service companies have told me to give them! Anyone else know the answer to this? – G
#6663From: CSA/CADec 12, 1991 6:27 PM
Gary, Well, heck, nobody asked me…! And by the time I'm finished, you'll remember why. I think the confusion originates because of the differences between screen ratio, file ratio & film ratio. Work on an image in the same screen proportions as the film ratio. 35mm is a 1.5:1 ratio (or 3:2) & 4×5 film is 5:4. A .TGA image of 512×482 on a monitor is 4:3 (hey, nobody said we're always using square pixels). Output to 35mm film would be 512×342 pixels, or a multiple (1024×684 or 2048×1368). For 4×5 film, use 512×384 (or 1024×768 or 2048×1536). I hope this explains the common use of 2048×1536 by service bureaus. You can also FIT (leave unexposed areas surrounding left & right sides) or CROP (leave off some information on the top and bottom of your image) for other formats. In traditional photography, to print a 35mm negative onto 8×10 paper, you either crop off some of the negative, or print the entire negative onto the paper, leaving some of the paper surrounding the negative unexposed. We could also go into film density (2k resolution on 35mm is 2048 pixels per row measuring 1.5 inches, equal to 1366 pixels per inch, on 4×5 it's 2048 pixels over 5 inches, thus a pixel density of 410 per inch). A pixel on 4×5 film is roughly 3.3 times larger than the same resolution on 35mm film. The image begins to look "blocky". To get the equivalent of 2K 35mm quality on a 4×5, you need an 8K file, for 8×10 you'd need 16K to maintain a high level of pixel density. So I hope the Yost Group's lab has a Forte. May I recommend the book I "stole" all this from: Basic Digital Photography by Norman Breslow (a CSA customer, of course) from Focal Press, available in many technical book stores. Published by Butterworth-Heinemann, 80 Montvale Ave., Stoneham, MA 02180. Kevin Krell – Computer Support Associates
#6666From: Noah KennedyDec 12, 1991 7:41 PM
Kevin- excellent. thanks. –Noah
#6616From: CSA/CADec 11, 1991 8:19 PM
Sherwood, Might as well make it 1:1 (aspect 1.0). Gary makes some good points re: memory requirements. Might as well choose a resolution that matches the output type (2K x 1.5 for 35mm, for instance). If you can use 4K x 4K, well, by all means, go ahead. Kevin Krell – Computer Support Associates