When I say the Mac is pretty much the standard in graphic work I mostly mean "still" stuff. For every person doing computer animation there's probably a hundred doing page-layout, web design, and other print stuff on a Mac.
Still, the Avid video editing system was originally built around a Mac.
True story: there was this fellow in the mid 80's that worked at Skywalker Ranch doing computer animation on their SGIs with proprietary software. He was so impressed with his new Mac he wrote a little program that could do similar things. After a while his little program could do some really cool stuff that folks hadn't seen done on a desktop computer before. He searched around to see if anyone was interested in marketing his program but had a hard time finding anyone. Finally, this little "font" company called Adobe took an interest in it and renamed it Photoshop. And it's done pretty well.
It's been awhile since I had an SGI but they are pretty cool boxes. I was always fond of the IRIX operating system and it's development tools. When I worked in UNIX ports at Autodesk we were working on AutoCAD for Sun, SGI, IBM AIX, and HP-UX at the same time. We had a quad-processor SGI Crimson that could compile an AutoCAD with debug symbols in 30 minutes. Our top of the line dual-processor Intel NT box with a custom C++ compiler from Microsoft took over six hours to do the same task.
Unfortunately, SGI isn't doing so well nowadays. I still see a few of their servers at the datacenter where I keep mine but not as many as I used to. On the other hand, SGI is doing lots of stuff with Linux now which is good.
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