question about exposure

shingfan · Feb 21, 2007

EOS_JD said:
light meter is the way to go.

i'm looking for alternative method.........as i dont have a light meter and not ready to spending any $$$ on getting a light meter

Digital Matt · Feb 21, 2007

The alternative is to use the mathematical equation. Flash intensity is controlled by aperture alone. If you are balancing available light and fill flash, you'll have to do a reflective meter reading to determine your shutter speed and aperture combo, then you'll have to do some math to figure out what power level to set your flash to in order to balance. I gave you some links above to several good websites. Here is the one again that explains the math you'll need to figure this out.
http://www.cs.mtu.edu/~shene/DigiCam/User-Guide/FZ-10/Ext-Flash/Basic-Functions.html

If you don't want to do it that way, then you are left with a light meter, or guessing. I think you can see which is the smarter way to go.

Stevedevil · Feb 21, 2007

A way forward would be by trial & error, position your subject, take your camera light meter reading and write this down ( no flash reading ) set an ISO and then highest f stop and take a picture write down settings, then adjust f stop by 1 and take another, etc, then download and see which is best photo, then you will see the range of the strobe for that situation, as your light meter will be giving you the reflex light on the subject, from the lamp you are using as modelling, then try some different subjects, clothes dark & light and write down all, you will soon have a chart you can use for reference based on the light meter ( in camera ) against the F stop & ISO settings

Or get a light meter I guess

Steve

shingfan · Feb 21, 2007

hmm.....i guess the replies are getting a little off topic.....my original question was how do i know if i have a good exposure.......i know how to adjust the flash level, ISO, aperture, and shutter to get different exposure......but by looking at the little screen on the camera....i'm not able to tell whether the exposure is good or not.....of course....if i upload the files to my computer...then i can tell whether it is under/over exposed.....but i'm trying to find a way to tell whether the picture is properly exposed when i take the shot......i guess looking at the histogram can only solve part of the problem if i dont have a good understanding of what i should expect to see in the histogram.........i guess i'll learn over time as to which method suits me the best....thanks a lot for the comments......appreciate them all

Digital Matt · Feb 21, 2007

I didn't tell you how to adjust the flash and exposure settings. I gave you a formula to adjust them so that you will get the correct exposure. There is no guessing, or looking at the histogram. There is a science to this. Film cameras don't show histograms. The only way to know if you got a good exposure is to know what you are doing in the first place, so that you get consistent results every time.

shingfan · Feb 21, 2007

Digital Matt said:
I didn't tell you how to adjust the flash and exposure settings. I gave you a formula to adjust them so that you will get the correct exposure. There is no guessing, or looking at the histogram. There is a science to this. Film cameras don't show histograms. The only way to know if you got a good exposure is to know what you are doing in the first place, so that you get consistent results every time.

as usual....you comments are great....and i already bookmarked the sites you gave to me and will read it when i get home

is hard for a beginner like me to disgest everything and know exactly what i'm doing every time....but i'm trying hard to apply more physics into it so that i get more consistent results.......

Matt....can you have a look at my new photos in the wedding/portrait gallery section......hope you can give me some technique comments

here is the flickr link

http://www.flickr.com/photos/47091458@N00/