I have notice an odd phenomenon. e.g.: I'm working on a pretty large Bryce file (50-60Mb), make some changes and then save it. I then start the render and it tells me something atrocious like 5-1/2 hours or much more, and if I let it just go, it takes that damned long to render. On the other hand, if I stop the render after the first pass when it shows the 5hr estiomated time, change to a different view, such as top, then back to my main view, and/or click on some object (sometimes I have to do both) and make a TINY change, such as moving it 0.01 z+, I can then click on the render button and after the first pass it gives me an estimated render time of something like 35-45min, and that's roughly how long it actually takes. I've duplicated this with a lots of files, and it's weird, but it seems to work every time for me. (B4 on a win98, PII-400mhz w/ 256M ram system, BTW - on which about 85Mb is the largest file size I can work with unless I want to wait a couple Minutes after clicking just for something to f***ing highlight so I can edit it).