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**Alkanyadela** · 04-29-2008, 01:20 AM

i would think with higher aperture size still most of the image would be sharp (at least a wider range)? with lower aperture like 2.8 wouldn't it be more blurry ? (again i am no expert on photography but just was thinking about some settings i use) when i want to take a close up macro shot and want the background to be as blurry as i can get, i usually set my aperture size to say f/2.8 and set a as high shutter speed as i can (or should maybe say shortest exposure time depending on the light).... .... ok i am confused by all the things i wrote [rofl][rofl]

man go on ebay buy an old camera and some films which passed their expiry date :-) [rofl]

Well, you're saying two different things between this post and your last. A larger aperture (f/1.4 or f/2.0 etc) will allow for a faster shutter, reducing motion blur. However, the depth of field would be more shallow, leaving less of the image in focus, and at the same time, due to the optical limitations of most lenses, the elements that are in focus would be less sharp (but still not out of focus). With a smaller aperture (f/9 or f/11, etc), the depth of field will be very large, meaning that more elements both in front of and behind the focal plane will be in focus (and those things that are in focus will be sharper).

Imagine that the depth of field at f/1.8 (with an 85mm lens on a crop body from a distance of 10 feet) is 0.28 ft and that the depth of field with the same setup but at an aperture of f/9 (a smaller aperture) is 1.41 ft total. Now, suppose you fill the frame with a sheet of paper and no elements creep into the frame other than that single sheet. In either instance, the entire sheet can be in focus (because the depth of the objects in the field of view is less than the overall depth of field in either instance), but because of the optical properties of any lens, the same image will be sharper at f/9 than it will be at f/1.8. This site will help you understand depth of field better (notice the diagram with the trees and at the bottom of the green table).

That said, I think the OP could serve his purposes with something like a Holga or Diana camera, if he doesn't mind shelling out $25 or so for the camera and ~$8 for film and processing.

04-29-2008, 01:20 AM	#8
Alkanyadela Join Date Oct 2005 Posts 460 Senior Member	i would think with higher aperture size still most of the image would be sharp (at least a wider range)? with lower aperture like 2.8 wouldn't it be more blurry ? (again i am no expert on photography but just was thinking about some settings i use) when i want to take a close up macro shot and want the background to be as blurry as i can get, i usually set my aperture size to say f/2.8 and set a as high shutter speed as i can (or should maybe say shortest exposure time depending on the light).... .... ok i am confused by all the things i wrote [rofl][rofl] man go on ebay buy an old camera and some films which passed their expiry date :-) [rofl] Well, you're saying two different things between this post and your last. A larger aperture (f/1.4 or f/2.0 etc) will allow for a faster shutter, reducing motion blur. However, the depth of field would be more shallow, leaving less of the image in focus, and at the same time, due to the optical limitations of most lenses, the elements that are in focus would be less sharp (but still not out of focus). With a smaller aperture (f/9 or f/11, etc), the depth of field will be very large, meaning that more elements both in front of and behind the focal plane will be in focus (and those things that are in focus will be sharper). Imagine that the depth of field at f/1.8 (with an 85mm lens on a crop body from a distance of 10 feet) is 0.28 ft and that the depth of field with the same setup but at an aperture of f/9 (a smaller aperture) is 1.41 ft total. Now, suppose you fill the frame with a sheet of paper and no elements creep into the frame other than that single sheet. In either instance, the entire sheet can be in focus (because the depth of the objects in the field of view is less than the overall depth of field in either instance), but because of the optical properties of any lens, the same image will be sharper at f/9 than it will be at f/1.8. This site will help you understand depth of field better (notice the diagram with the trees and at the bottom of the green table). That said, I think the OP could serve his purposes with something like a Holga or Diana camera, if he doesn't mind shelling out $25 or so for the camera and ~$8 for film and processing.
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