Getting a blurry background?

[Breezy Smeezy]

I'm shooting for a conference and I love the shots with the subject in focus and a heavy blurred background behind the subject. I have a Nikon D5000 with a 18-55mm and a 55-200mm lense. Is it a certain lense that helps with the background or is it stictly settings like aperture priority that will give me the blur?

 

[AdamK]

Well both really. With aperture priority you set the aperture so a larger aperture (smaller number) will blur the background and sharpen the subject and a smaller aperture (bigger number) will bring everything into focus, play around a little and you'll understand. But certain lenses can reach certain apertures look on the lens and you'll see a number that looks like '3.5-5.6' that is the largest aperture my lens can get yours may say something different. I'm sorry about the long discription.

 

[Breezy Smeezy]

My lenses are the same, but the light is so low, I bump up the shutter speed, but then the subjects move so fast, they turn out blurry. On top of that, I have it at f5.6 but the background isn't blurred enough...

 

[Arkanjel Imaging]

DOF will depend on your lens magnification, aperature setting, distance to subject and distance between subject and background. Ideally you want to use the shallowest (small number like f/2.8) DOF possible to seperate subject from background. Many consumer level lenses dont go that low so getting blurry bg's becomes more difficult. You will probably be better off with your 200mm if you have the working distance. Also the farther you can put your subject from the background the better as this increases the blur effect (or bokeh).

My lenses are the same, but the light is so low, I bump up the shutter speed, but then the subjects move so fast, they turn out blurry. On top of that, I have it at f5.6 but the background isn't blurred enough...

Dont be afraid to use a higher ISO to keep shutter speeds fast. And another option you have is blurring in your post processing via Photoshop. Very easy to do these days.

 

[AdamK]

My lenses are the same, but the light is so low, I bump up the shutter speed, but then the subjects move so fast, they turn out blurry. On top of that, I have it at f5.6 but the background isn't blurred enough...

Ok in low light situations use the ISO and choose a high ISO depending on the light intensity. The situation of the background not being blurry enough is that the biggest aperture you can set?

 

[Overread]

The best book for reference on this subject is "Understanding Exposure" by Bryan Peterson and I strongly recommend you read a copy of this book for a fuller grounding in the overall topic of exposures and controlling them.


As for the subject of blurry backgrounds there are several factors that come into play here:

1) Aperture - the larger the aperture (smaller the f number) the smaller the depth of field you will have in a shot. This is the area of the shot that is in focus - thus for a more blurred background having less depth of field helps to isolate the subject from the background

2) Separation between subject and background - generally speaking the further away the subject of your shot is from the background to the shot the greater the blur will be on those background areas. So shooting someone leaning against a wall will be hard/impossible to get a wellblurred background on the wall - but place them a few meters or more away from that wall and the blurring increases (the wall/background is essentially further outside of the depth of field and thus blurs)

3) Focal length of the lens - for the same framed shot (ie the same content and composition) using a longer focal length will result in a greater overall degree of separation of subject and background

There are some other factors, but I don't think I'm going to do justice to the descriptions at this time of night - so again I recommend reading the book mentioned above. It will also go a long way to helping you understand how to select settings to use for different situations and for different shot types.

 

[bigtwinky]

My lenses are the same, but the light is so low, I bump up the shutter speed, but then the subjects move so fast, they turn out blurry. On top of that, I have it at f5.6 but the background isn't blurred enough...

Thats why shooting low light and freezing action requires good gear, well, better gear than what you have. Constant f/2.8 aperture lenses or fast primes (f/1.8 and wider) are essential as is a camera that can do a clean ISO 1600 and up.

The three things that affect the blurryness of the background:

1- wide aperture. Wider = more blurry
2- focal lenght. Longer focal lenght = more blurry (ie 50mm vs 200mm, 200 will give more blurry)
3- distance of subject to background. More distance = more blurry

 

[SageMark]

Since this thread has been answered with a wealth of information, shall we turn this thread into how to correctly pronounce Bokeh? It's commonly pronounced incorrectly, so to fit in, I do.:meh:

 

[Breezy Smeezy]

I'd sincerely like to thank everyone who is helping me out. All of it is very useful information.
I've tried everything from setting the ISO up to 3200, setting the aperature to the lowest setting I can (which is only 5.6 :/), I put the 200mm lens on it, but with that lens, it's too close and my angle isnt wide enough. There are a lot of people at the convention, and so the intention of the blurred background is to not have any other people as distractions in the shot... that's my problem.

Another question, if 200mm optomizes blurriness, are 35mm with f1.8 not okay?

 

[zamanakhan]

35 1.8 is good but it doesnt give u a a great blurred background because it is essentially a wide angle lens (altho standard on ur d5000) the best thing to do is get as close as possible to the subject with the 35 and leave it at 1.8, use a bounce flash (if u have one). Pretty much everyone has hit the nail on the head of what ur supposed to do, so get out there do it!!! maybe rent a lens for the occasion? a 70-210 will give u AWESOME results

 

[table1349]

Good tutorial on DOF. Understanding Depth of Field in Photography

 

[djacobox372]

I'd sincerely like to thank everyone who is helping me out. All of it is very useful information.
I've tried everything from setting the ISO up to 3200, setting the aperature to the lowest setting I can (which is only 5.6 :/), I put the 200mm lens on it, but with that lens, it's too close and my angle isnt wide enough. There are a lot of people at the convention, and so the intention of the blurred background is to not have any other people as distractions in the shot... that's my problem.

Another question, if 200mm optomizes blurriness, are 35mm with f1.8 not okay?

A lens that only goes down to f5.6 is not likely to blur the background as much as you want, not unless it's a very long telephoto (400mm or more).

This is why people spend all the extra $$ to buy lenses that can go down to f2.8 or even f1.4

 

[KmH]

Since this thread has been answered with a wealth of information, shall we turn this thread into how to correctly pronounce Bokeh? It's commonly pronounced incorrectly, so to fit in, I do.:meh:

Well no, because a blurred background and bokeh are not the same thing.

Bokeh is mostly a function of how a lens is corrected for spherical aberration, by the number of aperture blades, and the shape of their edges, because that defines the shape of the lens aperture and that lenses circle of confusion. Circle of confusion - Wikipedia, the free encyclopedia

 

[thatfornoobs]

Oh wow.