Exposure Combinations

[Cassie]

I have quick question about combinations :oops: after reading Understanding Exposure I'd like to begin using M most and try to wrap my brain around this combination stuff.

On this site it gives a sample combination.........http://www.uscoles.com/fstop.htm (tried to post but the combintaions section doesn't line up right)

My question is.......when making adjustments and your setting are in 1/3rds, do you need to change shutter/apeture only when you reach the next whole stop?

for example: if I'm using f/8 and 1/125 and go to the next apeture its 7.1 then 6.3, will I only be required to change the shutter once I reach F5.6:eek:

~Cassandra~

[kmb]

My question is.......when making adjustments and your setting are in 1/3rds, do you need to change shutter/apeture only when you reach the next whole stop?
No. You adjust the shutter speed respectively in 1/3rd stop steps. Any adjustment to aperture will increase/decrease the amount of light that will be passed through the lens, so to get similar exposures you always need to adjust shutter speed to match the new aperture, so to speak. I hope this helped :)

[Briancd]

I have just started to use M and my process is to determine what aperture value I need, to get the required depth of field, then I adjust the shutter speed until the exposure level icon is centered. Or conversely, if shutter speed is your priority, to stop movement or create a sense of movement (waterfall) then set the shutter speed first then adjust the aperture value. All this is done after you half press the shutter button and get your focus.

[Eoseni]

KMB is right. Don't forget that with digital, the ISO can also be changed on the fly...giving you the "Photographic triangle," that is, ISO, shutter speed and aperture. Some cameras have ISOs also in 1/3 stops but most have them in one stop increments.

Good luck and Happy learning.