I searched but found no answers

Quizbiz · Jan 17, 2005

I tried searching on google and on this forum and I am yet to find the reponse I am looking for so please don't yell at me asking such silly questions.

1) What is the ISO speed? I have read a bit on it, but I still don't understand how it effects a photograph.
2) My camera has the ability to change "Focus-BKT", I lost the manual

, and even though I have been playing with the camera, I havn't found out how changing it effects my pictures. So what is BKT? How does it effect a photo?
3) What is AEB? How does it effect a photo?

4) When should a flash be used? When should the flash be avoided? I just want to learn from those of you guys who are most experienced.
5) How can i take quality high shutter speed photographs of the basketball team at my school? My flash doesn't get very far, and even at at 100th of a seccond, the picture comes out too dark forcing me to make changes on photoshop. So far i have taken my pics with a 160th of a seccond (which isn't very clear) and I have to brighten it up a lot on photoshop. I havn't messed around much with anything but the shuitter speed...

MDowdey · Jan 17, 2005

ISO is how fast the film will take in light. changing the iso will change the exposure numbers so that in low light situations, you can use quicker shutter speeds. but beware...changing to a higher iso usually means more grain in your film.

BKT is bracketing, this is handy for when you arent 100% sure of the exposures for a shot, it will let you stop down and up by either half a stop or a whole stop..

md

ps.s. if any of thats wrong, mattfish can flog me later...

Quizbiz · Jan 17, 2005

MDowdey said:
BKT is bracketing, this is handy for when you arent 100% sure of the exposures for a shot, it will let you stop down and up by either half a stop or a whole stop...

I read something on the lines of that somewhere on google yet I understood nothing.

MDowdey · Jan 17, 2005

well it essentially gives you three chances to get the exposure right from what you kinda thought they were. lets say:

1)sunny day

2) you set your shutter at 1/250 and your aperture at f8.0/

3) some clouds roll in and your not 100% positive on the settings, so you press the bracket button. and it takes three shots. lowering the aperture for one, doing it at f8 for one, and raising the aperture for one. you now have three distinctly unique shots to choose from

md

Quizbiz · Jan 17, 2005

Ah thanks!

Jeff Canes · Jan 17, 2005

AEB is an auto bracketing setting. You pre-set it as you desired. Then take 3 shoots of your subject. Each shoot with be at a differ settings

BernieSC · Jan 19, 2005

ISO is International Standards Organization. It is a measure of standards the film is made to specific standards which relates to how it is effected by light etc... Its the same no matter if you buy it today or 10 years from now. Kind of like a light bulb base is made to fit any light fixture.

walter23 · Jan 19, 2005

Okay, here's my attempts:

1. ISO - film (or digital sensor) sensitivity. At low ISO, it takes more light to give the same level of brightness on the sensor/film. At high ISO, less light will give an equally bright image. These are standardized, and each doubling of ISO results in film that is twice as sensitive - ISO 200 is twice as sensitive as ISO 100. This doubling of sensitivity is also equivalent to the photographic idea of a stop. When you change your aperture from f/8 to f/5.6, or your shutter speed from 1/125 to 1/60th, you're letting twice as much light in. This is called a single stop, in this case one stop more exposure. The opposite, one stop lower, is half as much light - e.g. going from f/8 to f/11 aperture, or 1/125th to 1/250th shutter speed. So you can compensate for a change in ISO by changing something else by a stop in the opposite direction and get the same exposure for an identical scene.

2. Focus-BKT - I googled that term and it looks like it's a canon powershot feature that changes the focus over a number of shots... so if you're focused on something 2 feet away, and choose a focus-BKT mode, you can take three pictures focused at 1.5, 2 and 2.5 feet. I made up those numbers, but you get the idea - the point is to help you focus in cases where it's hard to tell, so afterwards when you copy the photos to a computer you can throw out the bad ones and keep the ones that have the proper focus.

3. AEB - same concept, applied to exposure. If you do AEB with a setting of half a stop, you'd get three photos at -1/2, 0, and +1/2 exposure, where 0 is the exposure the camera would select based on its light meter and the others have the shutter speed or aperture altered by half a stop. This way if you're not sure how bright the scene should look in the final result you can look at all three later and throw out the bad ones.

Flash - I'm afraid you're screwed if you want to use your on-camera flash indoors at long distances. You could get a more powerful flash, or try to use available light by turning the flash off, though this would probably give you blurry photos since your shutter speeds will most likely be pretty low. You could try to set your ISO high (say 800) to help out by making your camera more light sensitive, but your pictures will be grainy or noisy looking.