800 iso or 1600 iso

If you guys are taking pictures in low light of people far away, would you prefer to shoot at F/2.8 and 800iso or F/4 and 1600. Cuz at 2.8 i would be shooting wide open which doesn't give as sharp of pictures as stopping in down but 1600iso isn't great either. Which is better and will yield sharper images.

I would suggest you try it and see for yourself what you like. It depends on how big the print will likely be, and how much depth of field you need.

I'd go for F2.8 @ iso800 most of the time. People @ distance will not need a great deal of dof (unless they are a large group or your using a long lens) and the difference in noise between 800 and 1600 is considerable IMO. With your set of lenses F2.8 shouldn't be as much of a compromise. Worth giving both a try though, learning your kits abilities and limitations is allways worthwhile.
Dellboy.

I always try to keep the ISO as low as possibly, not sure how good the Tamron is wide open. The best thing is to shoot as many as possible at both 800 and 1600 and then pick the ones that are best.

I shoot the Tamron wide open all the time, no problems at all. Gets a little sharper at F4.

I'm with Tim ... my Tamron at f/2.8 is fine ... at f/4 it's razor. I use f/2.8 all the time and often prefer narrow DOF over a super sharp image. Sharpness isn't the bee-all-end-all.

Open those lenses up, and get a good Noise Reduction plugin (I recommend Noiseware) and you're good to go for ANYTHING. Right up to ISO 3200.

PS I hope you beg/borrow/steal a second body when you shoot weddings. Don't even think about shooting without a backup.

I use f1.8 or 2.8 with ISO 1600!

Thanks guys. Yeah i am going to do some tests and see what i like but i think that i would prefer to open up my Tamron and 800iso. And bpuppy, i have another 20D available and of course i wouldn't shoot a wedding without a second body.

Working on my skills and understanding of photography so here goes! Why is the larger apperature going to make a differnce in the sharpness? Thanks!

Lenses are just sharper with small apertures, because of the physics of the way they work. Someone else should be able to give you a better explaination.

I thought their optimal setting was around midpoint at f8 or similar ?

Whatever the case, the top lenses will perform very well wide open.

i concur! me too. i love 1600, rarely use anything else.

i'm shooting my daughters graduation tomorrow in low lighting conditions, inside, at night. the kids will be on the temple bima at eye level. my lens choices for my 20D are either my 75-300 5.6 (even with my 430 flash i'm guessing the pictures will be dark) or with a 200-700 2.8, which i'm borrowing from a friend. i have never used that lens before and would appreciate ISO suggestions. i won't know how close i'll be able to get to the kids -- we have been asked to stay in our seats for the ceremony. should i shoot on full automatic?
thanks,
jennifer

luckymomoftwins wrote in post #5654594
i'm shooting my daughters graduation tomorrow in low lighting conditions, inside, at night. the kids will be on the temple bima at eye level. my lens choices for my 20D are either my 75-300 5.6 (even with my 430 flash i'm guessing the pictures will be dark) or with a 200-700 2.8, which i'm borrowing from a friend. i have never used that lens before and would appreciate ISO suggestions. i won't know how close i'll be able to get to the kids -- we have been asked to stay in our seats for the ceremony. should i shoot on full automatic?
thanks,
jennifer

That's a tough call... I'd either shoot manual or Av mode... watch your shutter speed and bump ISO to make sure you're shooting s shutter speed fast enough.

Shoot on manual, ISO1600, F2.8, experiment with the shutter speed but start at 1/100th. If people are still you can get away with 1/30th (though take a few shots of each because they won't all be good), if they're moving try for 1/125th. Use the flash, direct, ETTL, FEC+1. Watch the histogram. Take a shot without flash to start with to make sure you're not overexposing the ambient, then add flash if you need to.