Bruce From United States of America, joined May 1999, 5090 posts, RR: 13 Posted (14 years 6 months 2 days 2 hours ago) and read 2530 times:
do you think I should use 100 speed or 200 for outdoor daylight shooting? What if it's cloudy or hazy outside?
Does 100 yield less "graininess" in the print and hence, a sharper photo?
What would it do to the picture if I used 100 on a cloudy day?
I have been using 200. I always thought to use 200 because it hardly ever seems to be bright and sunny where I shoot
I thought the rule of thumb was bright sunny = 100, partly to cloudy = 200 but this does not seem to hold true. I shot some non-aviation pics on my recent trip on a 100% sunny day and with the polarizing filter I got the deepest blue sky you've seen - using 200 film! What's up??
But I am wondering if 100 would be better results in making my pics a bit sharper (less grain) to be accepted.
Bruce Leibowitz - Jackson, MS (KJAN) - Canon 50D/100-400L IS lens
CYKA From , joined Dec 1969, posts, RR:
Reply 1, posted (14 years 6 months 2 days ago) and read 2519 times:
I tried anwsering your question on 100 ISO film in another post, in case you didn't see it, here it is again:
Yes, the lower the ISO rating the less grain. This means better colours, sharper pictures and less visible grain on the photo.
If one attemps to use 100 ISO film on a really dark, overcast day the f/stop on the lens would have to be set around f4 or f5.6 at 1/250(or f5.6 to f8 at 1/250 and so on) shutter speed to obtain the correct exposure.
The problem with that is that most lenses arent their sharpest at their lowest f/stop(typical zoom will be f4) and introduce artifacts such low contrast and vignetting to some degree. This problem only becomes a problem when using a long focal length while shooting action or even still's where the shutter speed has to be around 1/500 to avoid motion blur or hand shake, if your not very good at panning or don't have a steady hand.
Therefore it is best to use most lenses at f8 which is only possible in decent sunlight. If you use a point & shoot(which often have lenses slower then f5.6), then your compact camera will simply select a slower shutter speed which will mean you will have to hold your camera really steady to avoid blurring.
So what it all come down is is that its best to use 100 speed fim in even the worst condtions for still shots and using 200 or 400 speed films for action in equaly bad condtions.
Jwenting From Netherlands, joined Apr 2001, 10213 posts, RR: 17
Reply 2, posted (14 years 6 months 1 day 19 hours ago) and read 2510 times:
Less grain does not mean better colours. The colour reproduction is determined solely by the chemical makeup of the emulsion, and not by the size of the grainclusters (or even individual particles).
The sharpness of the pictures is also not reduced by using a faster film. The PERCEIVED sharpness may be reduced, if the increased grain cannot reproduce that the lens produced.
Grainsize is also not a factor only of filmspeed. Some ISO 400 films have finer grain than other ISO 100 films (e.g. Fuji NPH compared to Kodak Gold 100 (RIP)).
Grainsize of slidefilm is also quite different from that of printfilm of the same speed. An ISO 100 slidefilm will usually have larger grainsize than ISO 100 printfilm (though it may be perceived as finer when scanned or projected).