[Help] How to Focus On Subject & Blur Background?

hikkifan17

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Hi,

I am new to the world of "Photography"and I was wondering, how do I focus on a subject but have the background blurred? I presume this question has been asked once or twice.

I have a "Fujifilm Finepix S4200", I tried to follow some instructions on how-to site but having trouble still. Could anyone be willing to share a step by step tutorial of some kind? If so that would be great. Thanks.
 
I'm not familiar with your camera but you want to use a wide open aperture aka small aperture number.
 
It's about much more than just the lens aperture. Point of focus distance, focal length, and how far from the subject the background is all factor into what you are wanting to do.

What you are wanting to do is known as 'selective focus' or a shallow depth-of-field. This tutorial includes a DoF calculator - Understanding Depth of Field in Photography
 
set to A, Apperture Priority AE then put it the number low F3.1 to get the blur background.
The bigger the number F then the background will become more clear.

Cheers
 
Thanks for the tips, I will look into it. More tips welcome ;D
 
To increase the effect of the blurred background, you may want to ..


- Choose a wider aperture that is smaller the f number.
- Choose a longer focal length. The longer the better.
- Decrease the subject to camera distance. The shorter the better.
- Increase the subject to background distance. The longer the better.
 
For various reasons you could imagine reading the suggested article, compact cameras give much less blurring than dSLR, unless on extreme conditions (e.g., subject extremely close and background proportionally far, like in macros). So, be prepared to get frustrated: it's not as easy as you wish.
When using a DoF calculator (e.g. Depth of Field Table ), remember to use the real focal length and not the "equivalent" one. In the case of your camera, 4.3-103.2mm. And remember that f/3.1 is available only at the shortest side, at max extension you have f/5.9.
 
If you want to do this, you'll probably want a different camera. The Fuji Finepix S4200 has a 1/2.3" sensor which is very small compared to most cameras.

The factors which influence your ability to create out-of-focus background are:

1) Long focal length lenses (the longer, the better)
2) Low focal ratios (lower is better)
3) Physically larger sensor sizes.

The challenge you'll have have with the S4200 is that it's lowest focal (f/3.1) ratio is only available when at it's widest angle (shortest focal length). But longer focal lengths help achieve the out-of-focus backgrounds. When you increase the focal length of the lens by zooming, the focal ratio increases to f/5.9 -- so you get the focal length you need, but you lose the aperture you need. And then of course there's the tiny sensor size.

You'll want to put the "focused" subject close to the camera and put as much distance as possible between the subject and the background. On a camera with a larger sensor such as the many APS-C or larger sensor cameras, the subject doesn't need to be all that far in front of the background to achieve the effect, but on your camera you'll need quite a large distance. Even so, the effect will not be as dramatic as what you are hoping for.
 
If you want to do this, you'll probably want a different camera. The Fuji Finepix S4200 has a 1/2.3" sensor which is very small compared to most cameras.

The factors which influence your ability to create out-of-focus background are:

1) Long focal length lenses (the longer, the better)
2) Low focal ratios (lower is better)
3) Physically larger sensor sizes.

The challenge you'll have have with the S4200 is that it's lowest focal (f/3.1) ratio is only available when at it's widest angle (shortest focal length). But longer focal lengths help achieve the out-of-focus backgrounds. When you increase the focal length of the lens by zooming, the focal ratio increases to f/5.9 -- so you get the focal length you need, but you lose the aperture you need. And then of course there's the tiny sensor size.

You'll want to put the "focused" subject close to the camera and put as much distance as possible between the subject and the background. On a camera with a larger sensor such as the many APS-C or larger sensor cameras, the subject doesn't need to be all that far in front of the background to achieve the effect, but on your camera you'll need quite a large distance. Even so, the effect will not be as dramatic as what you are hoping for.

Wow. Thanks for a detailed information about this, I had a feeling that the camera I have is harder to achieve the effect but its doable just hard.

@Everyone Else: Thanks for the tips :]
 

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