How do I?

[Molly47]

What settings would I need to use to blur the foreground & blur the background but leave the middle in focus, I saw a photo today where it had that effect & it looked great
As a beginner am I aiming too high to try to attempt something like that at the moment, I only have a 18-55 kit lens.

Thanks

 

[Simmotino]

What settings would I need to use to blur the foreground & blur the background but leave the middle in focus, I saw a photo today where it had that effect & it looked great
As a beginner am I aiming too high to try to attempt something like that at the moment, I only have a 18-55 kit lens.

Thanks

That effect is a shallow depth of field (or DoF).

You will need to set the camera to the widest aperture for the lens (the lowest f number) and, depending on the subject, you will have foreground and background out of focus.

It is likely that you will not be able to achieve both unless you have a lens that opens the aperture very wide (f1.8 and below) so you'll likely get better results aiming for having the background out of focus initially.

 

[Molly47]

Ah, I thought it might be aperture related. I can get shallow DOF in the foreground & background but I couldnt figure out how I would get both at once & leave the centre part in focus. Thanks.

 

[HoppyUK]

Yes, it's a shallow DoF effect and it's easy to do with a low f/number like f/1.8 or f/2.8.

Your lens doesn't go that low, but DoF is also reduced when the image gets bigger, so you can do it by zooming out to 55mm and moving closer. You obviously can't do that with all subjects, but give it a try.

You can calculate actual depth of field with this calculator http://www.dofmaster.com/dofjs.html

 

[EOS_JD]

Magnification is just as important (if not more so) than f-stop. A long lens will help a lot.

Your 18-55 is probably too short and not fast enough

 

[1.2f]

i have been trying to achieve this with my 15-85mm on my 7d, and have come to the conclusion that if i had bought a 17-55mm f2.8 as originally planned then i'd of had more success.

 

[Alastair]

Ah, I thought it might be aperture related. I can get shallow DOF in the foreground & background but I couldnt figure out how I would get both at once & leave the centre part in focus. Thanks.

When you are not getting out-of-focus areas in the foreground, then that means your focus point is too close and/or you don't have an object far enough in front of your focus point.

When you're not getting out-of-focus areas in the background you don't have anything far enough behind the focus point to be out-of-focus.

Try setting up three objects on a table, about 12" apart. Experiment with focus and aperture ro see what you can achieve.

Looking up the depth of field tables for your lens will let you see how the focus area extends in front and behind the focus target with different apertures.

 

[EOS_JD]

i have been trying to achieve this with my 15-85mm on my 7d, and have come to the conclusion that if i had bought a 17-55mm f2.8 as originally planned then i'd of had more success.

You would have had more success but the answer is get the subject closer and/or the background further away.