I was wondering though what is the best brand and the best ISO?
There is no "best" brand of slide film and no "best" ISO. There are two variables that matter here - color and grain. The lower the ISO, the finer the grain usually. Therefore you can blow up a lower ISO slide image larger and not see the film grain. You can actually find RMS scores for slide films in some magazines and online (like this site - http://www.photographic.com/film/143/). Once you settle on a fine enough grain (the difference between and RMS of 9 and 14 is pretty negligible, BTW), then you have to resolve the color issue.
I think i heard before that the Fujichrome Velvia 100 is the best (it must be for the price!) are there any other good (cheaper) brands. Also i was concerned with the speed of it.
Velvia is very rich in color, and tends to accentuate blues and greens over reds. This works well for most herps, which is why some people like it. It is also the favorite film of "camera snobs" who "never shoot anything else". My question to them is always "If you never shoot anything else, how do you know it is the best?"
I used to be a confirmed Velvia snob. One summer, a friend and I were forced to do a side by side comparison on a trip to Mexico. He shot Velvia ($8 a roll online) and I shot Ektachrome Elite 100 ($3.00 at Wal-Mart) because my Velvia didn't come in on time. As we projected our images side by side at home, we both agreed that the color rendition of the Ektachrome Elite was both more realistic and more pleasing for almost every herp shot. We both switched to the cheaper stuff (it is no longer available, unfortunately).
As for speed, slower ISOs give you finer grain, but I have to say the Fuji Sensia 400 mentioned on the list I linked above has a VERY low RMS score and would certainly be a worthy test film if you need the speed. Remember that doubling the film speed only gives you 1 stop, so 400 is only 2 stops faster than 100. Therefore if 100 needs 1/8 of a second exposure for a particular shot, the 400 is still going to need 1/30 sec. It often isn't a huge difference.
Sometimes with animals they move fast and dont always sit still. Will this film me i will have to use a much slower shutter speed?
I generally preferred slower film (ISO 100) and used a fill flash to compensate for slow shutter speeds. You get more control and more options than just using fast film.
Also about how much does this film cost to get developed? And whne you get it developed do you get prints or just the developed slides?
I used to buy my slide film online from B&H photo (bhphotovideo.com). I would buy the slide film that came with the prepaid mailers. It generally cost about $8 a roll for 36 exposures including processing if you buy 20 rolls at a time. If you buy slide film over the counter and pay processing at Wal-Mart, etc, it will run a total of about $12 for 36 slides.
You only get slides back, although for another couple of dollars, they will scan all the slides onto a CD for you.
Digital cameras seem expensive until you add up the cost of film and processing! I used to spend between $200 and $500 a year on film/processing. Since I bought my DSLR, I haven't spent a penny on it.
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Chris Harrison