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barnesquared
09-08-2005, 12:57 AM
i think im missing something.

my question is, how can i get long exposures in daylight without overexposing the picture? what f/stop and speed should i be shooting at? i tried various shutter speeds and aperture values, but my shots are always blown out.

suggestions? i have a canon digital rebel xt and shoot on M. thanks

nwpoland
09-08-2005, 02:27 AM
Just curious what you're trying to shoot?

It seems like you'd want the lowest ISO (I guess 100 on your XT), highest f/stop setting, and then you could try cranking down the exposure compensation. But still it doesn't seem like you'll be able to have a very slow shutter speed.

Then again, I guess a lot of this depends on what you're meaning by "long exposure".

cdifoto
09-08-2005, 02:29 AM
You can't really use a super long exposure in daylight. Even at f/32 you're going to be limited since the longer the shutter is open, the more light that goes in.

Not sure what you want to accomplish that you'd want/need a long exposure anyway. :confused:

ReF
09-08-2005, 03:21 AM
actually, it's quite possible. get yourself a neutral density filter (ND). of course, the longer you want to the exposure to be, the denser the ND required. there are even NDs that cut light by 9 f-stops and possibly more, but i can't remember off hand.

cdifoto
09-08-2005, 05:21 AM
actually, it's quite possible. get yourself a neutral density filter (ND). of course, the longer you want to the exposure to be, the denser the ND required. there are even NDs that cut light by 9 f-stops and possibly more, but i can't remember off hand.

Oh yeah. I forgot about those. For some reason polarizers are the only ones that ever come to mind. :rolleyes:

Thanks for that!

And yeah...that inability to delete posts is annoying. :eek:

barnesquared
09-08-2005, 12:25 PM
i guess i don't need a super long exposure.

would i need a filter to shoot say, water flows in a creek to get that misty, cloudy effect?

thanks everyone.

emalvick
09-08-2005, 02:19 PM
i guess i don't need a super long exposure.

would i need a filter to shoot say, water flows in a creek to get that misty, cloudy effect?

thanks everyone.

In short, Yes... If your shots are blown out, then you need the filter. All you need is an ND filter. As someone mentioned, it reduces the f-stop so that you need a longer shutter speed for the same exposure as without the filter at a specific aperture. This is good for trying to get that soft water look people often show in waterfall and or other blurring the action type shots.

Erik

nwpoland
09-08-2005, 10:49 PM
I'm just curious about other ideas to use this technique with. Great thought about water...and I'd forgotten about ND filters as well! :)

Katerine
09-09-2005, 12:12 PM
beware of hotpixels in any long exposure...

there are solutions for fixing hotpixels though, made easier if you have a matching 'lense cap' photo with all the same settings, taken imediately after the main image.

i dunno how bad hotpixels would get in broad daylight though, maybe they'd get washed out pretty well?

emalvick
09-09-2005, 02:03 PM
beware of hotpixels in any long exposure...

there are solutions for fixing hotpixels though, made easier if you have a matching 'lense cap' photo with all the same settings, taken imediately after the main image.

i dunno how bad hotpixels would get in broad daylight though, maybe they'd get washed out pretty well?

I don't think hot pixels will cause much problem because using an ND filter is only going to slow down the shutter speed down a little. Hot pixels become a problem at longer shutter speeds (associated with dark or night time shots). Here we are talking about probably slowing a shot down from 1/150th to 1/30th or something similar.

Although, I have seen people slow shots way down by stacking ND. Maybe hotpixels become a problem then. My camera actually takes two shots when shooting at 1s or slower. The first shot is the real shot and the second shot is a black shot. It then automatically subtracts the black shot from the original shot, effectively removing the hot pixels. I haven't seen them yet. I'd imagine that this is somewhat common.

Erik

emalvick
09-09-2005, 02:09 PM
I'm just curious about other ideas to use this technique with. Great thought about water...and I'd forgotten about ND filters as well! :)

I think water is probably the best way to use the technique, but I also find it useful at:

1. sporting events. For instance a runner or a race car... It gives a good dynamic to the photo. Catches the action with a blur. This often doesn't need the ND filter, but a bright day it may help.

2. Afternoon thunderstorms. I find it is good for giving a bit extra time when trying to shoot lightning in the afternoon.

3. Shots of fire or smoke can also be useful. Snapshots of fire usually seem empty in a way. Slowing the shot down lets the fire gain intensity in the image.

4. Other water type shots such as rain, water fountains, etc... all can give awesome shots with a slower shutter speed.

I'm sure there are many more.

Erik

nwpoland
09-10-2005, 02:12 AM
I think water is probably the best way to use the technique, but I also find it useful at:

1. sporting events. For instance a runner or a race car... It gives a good dynamic to the photo. Catches the action with a blur. This often doesn't need the ND filter, but a bright day it may help.

2. Afternoon thunderstorms. I find it is good for giving a bit extra time when trying to shoot lightning in the afternoon.

3. Shots of fire or smoke can also be useful. Snapshots of fire usually seem empty in a way. Slowing the shot down lets the fire gain intensity in the image.

4. Other water type shots such as rain, water fountains, etc... all can give awesome shots with a slower shutter speed.

I'm sure there are many more.

Erik

Great ideas to jumpstart my brain in this area...thanks! :)