Quote:
Originally Posted by andygrif
OK, on the two shots you posted I can see from the EXIF data that the first one you used a shutter speed of 1/30th sec and the second one a shutter speed of 1/15th (half as fast again). Realistically you shouldn't have a shutter speed under 1/60th as rule of thumb.
Now, going back to what Bender and I were on about... here's lesson two!
Exposure is measured in stops. f/2.8 is ONE LESS than f1.4 but ONE MORE than f/4. Your first shot was as f/2.8 which is a wide aperture. Your second shot was at f/4.2 (which isn't really an f/ stop, as one less than 4.2 is f/5.6!!!) Confused? It took me a while to grasp this one when I was learning it too.
So, the relationship between aperture and shutter speed is as follows: If you have an aperture of f/4 and shutter speed of 1/30th sec, by increasing the aperture by one stop to f/2.8 (widening the aperture) you also increase the shutter speed by one stop, from 1/30th sec to 1/60th sec.
ISO comes into this to as Bender said...in your first example your camera selected an ISO of 191 (which again is not a true ISO, so lets say it's 200). By increasing the ISO to 400 you are gaining another stop. So if we use the same exmaple of your f/4 aperture increase it again to f/2.8 and now we increase your 200ISO to 400, the shutter speed goes from 1/30th sec, through 1/60th (as increasing aperture got us this) and up to 1/125th sec shutter speed, which is a nice all round speed with no fear of camera shake at most focal lengths on your camera.
Does that make any sense? (Don't worry if it doesn't, it didn't to me for a long time too). If I remember, I will try and fish out my study in first year photography that I (eventually) grasped this relationship.
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---------- Post added at 10:53 ---------- Previous post was at 10:36 ----------
Quote:
Originally Posted by andygrif
OK, on the two shots you posted I can see from the EXIF data that the first one you used a shutter speed of 1/30th sec and the second one a shutter speed of 1/15th (half as fast again). Realistically you shouldn't have a shutter speed under 1/60th as rule of thumb.
Now, going back to what Bender and I were on about... here's lesson two!
Exposure is measured in stops. f/2.8 is ONE LESS than f1.4 but ONE MORE than f/4. Your first shot was as f/2.8 which is a wide aperture. Your second shot was at f/4.2 (which isn't really an f/ stop, as one less than 4.2 is f/5.6!!!) Confused? It took me a while to grasp this one when I was learning it too.
So, the relationship between aperture and shutter speed is as follows: If you have an aperture of f/4 and shutter speed of 1/30th sec, by increasing the aperture by one stop to f/2.8 (widening the aperture) you also increase the shutter speed by one stop, from 1/30th sec to 1/60th sec.
ISO comes into this to as Bender said...in your first example your camera selected an ISO of 191 (which again is not a true ISO, so lets say it's 200). By increasing the ISO to 400 you are gaining another stop. So if we use the same exmaple of your f/4 aperture increase it again to f/2.8 and now we increase your 200ISO to 400, the shutter speed goes from 1/30th sec, through 1/60th (as increasing aperture got us this) and up to 1/125th sec shutter speed, which is a nice all round speed with no fear of camera shake at most focal lengths on your camera.
Does that make any sense? (Don't worry if it doesn't, it didn't to me for a long time too). If I remember, I will try and fish out my study in first year photography that I (eventually) grasped this relationship.
.
|
Hi Andy
So what youre saying is manually change ISO to 400 - 800? For shots? This will reduce camera shake and blurry images?
Sorry i know noting about apperture and focal lengths. Theres nothing on my camera about these settings, the only settings it allows me to change are...
ISO - Auto,80,100,200,400,800,1000
White Balance - Auto, Daylight, Cloudy, Flourecent, Tungstun, Custom
Exposure Compensation - -2.0 ~ 0.0 ~ +2.0 ~ (0.5EV Steps)
Also with reading the manual i discovered the camera has an option of Continuous shot which can take Continuous shots until the shutter button is released, or AEB which is 3 pictures at different expsures. Under, normal, and over.
Manually the apparture is F2.8 + 7.1 Switchable When I zoom in it changes values also switchable. The shutter speed I can also change 1/15,1/30,1/45 Etc etc