Question about aperture and ISO speed

[Spearing Machine]

Prior to doing a photo excursion with steve foss I alwasy shot everything in auto mode and since then I have been switching myself over to AV mode on my rebel xt. So my question is is how do you deceide what combination of ISO and Aperture value to use?? Also is there a chart or something of the sort that may help he out with this or is complely a learned thing from experimenting??

[marine_man]

I'm starting out as well, and so far, have been using the "P" mode to see what the camera thinks, and experimenting from there.

marine_man

[MN Shutterbug]

I have got into the habit of shooting everything in Av as well. The smaller the aperture number, the shallower the depth of field. This is good when you want to get a buttery background. It will also give you a faster shutter speed, which is necessary for moving critters and birds in flight. However, when shooting a landscape, you are generally better with a higher number, such as 11 or 16. This is actually a smaller aperture, but with a landscape shot you are normally going to want as much in focus as possible. Of course, there are exceptions to the rule. F8 is a decent all around aperture, which is what my camera is set on when I leave the house. If it's fairly dim outside and I need to attain a faster shutter speed, I may open it up to 5.6. Either that, or I'll more commonly increase my ISO. If your lens will open to F4, this will give you the narrowest depth of field, which is real nice for individual flowers. Of course, there are some lenses that will open all the way to 1.4. They call these "fast" lenses, due to the fact that they'll allow you a faster shutter speed.

[Dbl]

If you take a look at the top of the forum you will find a sticky on "photography basics". Take a few minutes to read through that and if you have more detailed questions jump back in and someone will help you along.

[Spearing Machine]

Thanks X and DBL both help out quite a bit. Now I just need to go put it to work and see if i can make it all come together. I am looking to upgrade to a 30d as soon as i find a deal (too bad I didnt see the one here) so that will be even more fun to experiment with.

[Steve Foss]

Jeremy, check your e-mail. I just sent you one.

[Spearing Machine]

Steve, check your inbox!

[Steve Foss]

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