Metering with gnd filters

How is everyone metering when using gnd filters? I read an article recently that said to take your reading, lock it in and than insert the gnd to take full advantage. That did not seem right? I have also read to take the reading of the sky and than the foreground and subtract to get the filter strength but that is difficult when you are using a tripod, especially if it's low to the ground?

CameraBuff wrote in post #10566653
How is everyone metering when using gnd filters? I read an article recently that said to take your reading, lock it in and than insert the gnd to take full advantage. That did not seem right? I have also read to take the reading of the sky and than the foreground and subtract to get the filter strength but that is difficult when you are using a tripod, especially if it's low to the ground?

You should try LV. It makes inserting the GND a lot easier. I then go by the live historgram. It works well imo. I'm not sure if the 40D has LV. Does it?

jdizzle wrote in post #10568507
You should try LV. It makes inserting the GND a lot easier. I then go by the live historgram. It works well imo. I'm not sure if the 40D has LV. Does it?

Yes it does and I agree that that makes it much easier to use GND's.

Regarding metering, in LV you can move the white box around and provided you have at least the first bit of "INFO" on, you can depress the shutter half-way and see what the shutter speed will be. Could you meter the sky/ground with this to determine your GND needs? I thought so but I'll have to test it.

Thanks guys; looks like I will be experimenting more with live view in the future instead of just bracketing.

Eventually, you won't even have to mess around with determining exposures...you'll be able to judge pretty much by eye.

argyle wrote in post #10575953
Eventually, you won't even have to mess around with determining exposures...you'll be able to judge pretty much by eye.

Plus one! When you shoot enough with these filters, you'll basically never have to think about it.

HrcRacing wrote in post #10569025
Yes it does and I agree that that makes it much easier to use GND's.

Regarding metering, in LV you can move the white box around and provided you have at least the first bit of "INFO" on, you can depress the shutter half-way and see what the shutter speed will be. Could you meter the sky/ground with this to determine your GND needs? I thought so but I'll have to test it.

With LV it makes it so much easier. If you intend to do some exposure blending, I would bracket your shots.

Thanks guys. I do like that live view for landscape shots; one major reason why I now want to save for a 5dII instead of a 5d.

Great discussion. I intend to pick up a GND before a fall trip west to shoot the aspens in color. I had anticipated metering first, switching to manual and then inserting the GND. However, LV sounds like great advice. Unforutantly, my 50D eats up the batteries in the LV mode. Any advice to get around this?

georgebowman wrote in post #10635901
Great discussion. I intend to pick up a GND before a fall trip west to shoot the aspens in color. I had anticipated metering first, switching to manual and then inserting the GND. However, LV sounds like great advice. Unforutantly, my 50D eats up the batteries in the LV mode. Any advice to get around this?

Bring more batteries or don't use live view .

If you know how much light the GND cuts back depending on where it's position, you can turn the camera to spot meter, meter where the GND will be placed in the frame and where the GND will have no effect, calculate the difference, and then go from there.

You don't NEED to use live view - it's just another helping hand if you don't want to go through the hassle above (which is personally what I would do).