I am trying different things like changing every thing to get the sharpest picture with blurr background What If I take one and I liked it can I read the settings on that particular picture so I can set my self and get the same picture result pls help me
Learning to take photographs in M mode, confuse with Aperture / Shutter speed / ISO.
Don't have a clue yet lol !!!
Have Nikon D3100 & 18-55 lense
Here's a video which may help:
You might also want to pick up a copy of Brian Peterson's book "Understanding Exposure".
Ultimately what you are trying to do... get a sharp subject with a blurred background... requires that you create a narrow "depth of field" with the background located outside the depth-of-field (preferably far outside the depth of field.)
When you focus at a subject at some distance... say 10' away, it turns out there is a range of distances at which subjects will appear to be more-or-less in acceptable focus. If the camera is focused for PRECISELY 10' away... a subject located 9' 11" away is also probably in acceptable focus as is a subject at 10' 1" away... both values being extremely close to 10'.
But suppose another object is much closer or farther than the 10' mark... say 5'... or 15'... would those subjects be in focus too? The answer depends on the "depth of field".
Three factors influence the depth of field. On older camera lenses (and also on most non-zoom lenses) there are some markings near the distance scale on the focus ring which indicate the depth of field. You need to know the aperture or "f-stop" that the camera will use and these f-stops are listed near the focus ring with a near and far mark corresponding to that f-stop. Everything between the two marks (as indicated on the distance scale) is in acceptable focus.
Unfortunately modern zoom lenses almost never have these marks and even the prime lenses (a prime lens is a lens that does not "zoom") have focus rings geared for digital cameras where tiny movements of the focus ring translates into a larger change in focus than a manual focus film camera would have used. That means they don't have room to draw the marks.
So in these "modern times" we tend to use a Depth-of-Field calculator. There are apps for this, websites, charts, etc. If you have a smart-phone, you might want to download one. With a web browser you could visit this website: DOFmaster.com
But here are the general guidelines....
1) F-stop
A low focal ratio (low f-stop values... e.g. f1.4, f/2, f/2.8) tend to create a "shallow" depth of field.
A higher focal ratio (higher f-stop values... e.g. f/11, f/16, f/22) tend to create very "broad" depth of field.
2) Lens focal length
A long focal length (e.g. 100mm or 200mm) tends to create a "shallow" depth of field.
A short focal length (e.g. 10mm or 20mm) tends to create a "broad" depth of field.
3) Focused distance.
Close focusing distances... e.g. 1' or 3', etc. tends to create a "shallow" depth of field.
Far focusing distances (e.g. 50' or 100' away) tends to create a very "broad" depth of field.
This means if you put it all together... and what you want is a sharp subject with a blurred background, then you should use:
(a) a "long" lens... e.g. 100mm, and (b) use a low f-stop value (e.g. f/2.8... but even f/4 works well on such long lenses) and (c) a close subject distance but a distant background (don't put the subject up against a wall.... you want a bit of space between the subject and background.) then you get a stronger version of the effect.
Here's an example... this is a rather extreme example.
This was a candid I shot while I happened to be out for drinks with friends. But I took this shot using my full-frame camera with a 135mm f/2 lens...
So this is 135mm (a long lens), f/2 (a low focal ratio) and the subject is ONLY about 3' away ... while the background (the garden patio of a hotel) is much farther away. Here is the result:
IMG_2326 by
Tim Campbell1, on Flickr