Blur the background?

[Photoguy123]

Im very VERY new to this SLR camera stuff. I won a Nikon D80 at work and always loved pictures with the subject in the front and the rest of the shot blurred alot. How do you do this? Do most of you use the presets that come with the camera (sport, portrait, landscape) or do you use the manual modes to do the settings.

Thanks!


I wanted something like these....I got them from google images

 

[JimmyO]

Shots like those are made with lenses using big (smaller number is bigger) apertures (the number f/2.8)

You can also do things like that one photoshop also.

But you should set the aperture on your camera to the smalled possible number, probably f/3.5

 

[Photoguy123]

So put it to manual control and put it to f/3.5 and foruc with the lense manually till i get the desired results?

 

[djrichie28]

So put it to manual control and put it to f/3.5 and foruc with the lense manually till i get the desired results?

Either that or set the camera to Aperture Priority mode (A) and let the camera match a correct shutter speed automatically. Just set the Aperture to the lowest number, as mentioned, probably f3.5

 

[Crosby]

I used the aperture priority mode today but it is a film camera so I'll have to wait until I get them printed.

I used f/4 and auto shutter speed with ISO 400 film. I can't wait to see how they turned out but I hope the background will be blurred. The background is mostly of a budding Bradford Pear Tree (green and white).

Just read the camera manual and experiment with different settings. I would also recommend Understanding Exposure, a book that has been recommended to me from people on this forum. It has helped me alot!

Crosby

 

[onlybo]

Firstly,you must use the AV mode,secondly,turned the max Optical Zoom.
finally,used the Max Aperture Value.

so ,you can have a try,hehe.

 

[Socrates]

Im very VERY new to this SLR camera stuff. I won a Nikon D80 at work and always loved pictures with the subject in the front and the rest of the shot blurred alot. How do you do this? Do most of you use the presets that come with the camera (sport, portrait, landscape) or do you use the manual modes to do the settings.

Thanks!


I wanted something like these....I got them from google images

Very likely you're not going to be very successful with the lens that came with the camera. Use the aperture priority mode and open the lens up as wide as is possibler (smallest possible number). ALSO, get as close as you can. Those two actions will reduce the "depth of field" (the portion of the image that's in focus).

 

[kidchill]

Yah, if you can, do a google search for depth of field (DOF) and it will explain it. DOF is based on aperture, distance from the subject, and zoom level. If you want a shallow DOF that will allow the subject to be sharp and blur the background you want a large aperture 1/(smallest number possible), get as close to the subject as possible, and zoom in as much as you can!! Here's a link that has some really good tutorials for beginners including DOF!! That's a good place to start...

http://www.galitz.co.il/en/articles.html

 

[Mav]

You don't need a large aperture lens to get nice and shallow depths of field with blurry backgrounds.

my daughter on Easter Sunday about to get picked up to give her grammy a big ole kiss, heh heh

straight off the D80 with the 70-300VR and bounced SB-600, 185mm @ f/5.3, 1/125s, iso450, +0.7EV

kidchill has it right. Key in the shot above is the long focal length and relatively close subject distance. Also, check the "what is bokeh" link in my signature. I'm not sure what lens you might have gotten with the D80, but if it's the standard 18-135 lens then it's actually a pretty decent lens for portrait type photos, and has the best background rendering (bokeh) of any of the kit lenses.

 

[JerryPH]

Bokeh (the blurred background) is a result of three things:

- A large aperture opening
- The ratio of distance between you and your subject
- The ratio of distance between you and the area BEHIND your subject.

To blur the background, your aperture has to be big (as mentioned), but what I fail to see people explaining is that the greater the ratio of distance between you/background vs you/subject, the greater the blur will be.

This is why you can successfully blur things at apertures like F/5.6... the camera was VERY close and the distance behind the subject was proportionally higher.

This is why you can use apertures even as small as F/7 to create bokeh.

Elvis has left the building!

 

[Village Idiot]

I used the aperture priority mode today but it is a film camera so I'll have to wait until I get them printed.

I used f/4 and auto shutter speed with ISO 400 film. I can't wait to see how they turned out but I hope the background will be blurred. The background is mostly of a budding Bradford Pear Tree (green and white).

Just read the camera manual and experiment with different settings. I would also recommend Understanding Exposure, a book that has been recommended to me from people on this forum. It has helped me alot!

Crosby

Also iirc, 35mm cameras use more of the lens area so you'll get a shallower DOF with a higher f stop than using a digital cam with a crop sensor.

OP- JerryPH's post is a good one.

 

[JerryPH]

VI (I have a hard time calling anyone an idiot, sorry... lol), Field of view is not depth of view. You will see a wider picture with an uncropped sensor like a film camera or a digital body that has a full size sensor, but the amont of bokeh under the same circumtances would be identical.

... and the elvis pic is nowhere NEAR as cute as Mav's daughter is.

 

[Village Idiot]

VI (I have a hard time calling anyone an idiot, sorry... lol), Field of view is not depth of view. You will see a wider picture with an uncropped sensor like a film camera or a digital body that has a full size sensor, but the amont of bokeh under the same circumtances would be identical.

... and the elvis pic is nowhere NEAR as cute as Mav's daughter is.

http://en.wikipedia.org/wiki/Depth_of_field#DOF_vs._format_size
http://www.josephjamesphotography.com/equivalence/

DOF:

Understanding DOF, its connection to aperture, and thus the total amount of light that makes up an image, is critical. That is, for images created with the same shutter speed, the total amount of light making up the image, and the DOF of the image, go hand in hand. Let's begin with its definition: DOF is the depth of field, which is how much depth of the image is in critical focus. It is a subjective measure, to be sure, but is not arbitrary. That is, you can debate what an "acceptable" DOF is for a particular photo, but you cannot debate whether or not two photos have the same DOF -- that can be determined both visually and mathematically. It is important to understand that DOF is a function of many factors. For the same perspective, FOV, output size, and CoC (the CoC scales in the same way as does the focal length and f-ratio scale), the DOF is a function of the aperture, which is the ratio of the f-ratio and focal length. Since we change the FL to get the same FOV for the same perspective, we must also scale the f-ratio in the same proportion (multiply by the FM) to get the same aperture. For example, 25mm f/1.4 on 4/3, 31mm f / 2.5 on 1.6x and 50mm f / 4 on 35mm FF all have the same aperture since 25mm / 2 = 31mm / 2.5 = 50mm / 4 = 12.5mm will all have the same framing and DOF for the same scene. In addition, the same total amount of light will pass through the lens onto the sensor for the same shutter speed. The importance of total light, of course, is that two images of the same scene made with the same total amount of light will have the same quantity of noise if the sensors have the same efficiency.

Furthermore, larger sensors do not reach diffraction limited resolution at the same f-ratio as smaller sensors; they reach the diffraction limits at the same DOF regardless of pixel size. For example, a Canon 5D at f / 16 will suffer diffraction softening no differently than an Olympus E3 at f / 8. Let me explain a bit on the pixel size not being important in terms of diffraction. The smaller the pixel size, the more pixels that can fit on the sensor, and thus the more detail the sensor can resolve. However, with a smaller pixel size, the effects of diffraction will be more pronounced which will exactly cancel the extra detail of having more pixels.

Let's look at some examples of equivalent settings from common cameras (using the same AOV, not FOV):
Canon S3 @ 8.3mm, f / 2.7, 1/400, ISO 80
Canon G7 @ 10.3mm, f / 3.3, 1/400, ISO 125
Canon Pro1 @ 12.7mm, f / 4, 1/400, ISO 185
Olympus E510 @ 25mm, f / 8, 1/400, ISO 720
Sigma SD14 @ 29mm, f / 9.2, 1/400, ISO 950
Canon 40D @ 31mm, f / 10, 1/400, ISO 1125
Nikon D300 @ 33mm, f / 10.5, 1/400, ISO 1250
Canon 1DIII @ 40mm, f / 12.7, 1/400, ISO 1800
Canon 5D @ 50mm, f / 16, 1/400, ISO 2880
Mamiya ZD @ 67mm, f / 21, 1/400, ISO 5120

Note that some f-ratios are impossible since the cameras allow settings in only 1/3 stop increments. This same issue affects ISO settings if shooting jpg, but may be attainable depending on the RAW converter. In any event, we are talking about deviations of less than 1/3 of a stop, which I will disregard as insignificant. If you are so good of a photographer that less than one third of a stop is important, then this essay is a waste of your time! Also, please keep in mind that equivalence does not guarantee the same noise for equivalent images unless the sensors are of the same design and efficiency.

 

[JerryPH]

That pretty much supports what I said.

What you misunderstood is that a sensor cropped or not shows width, not depth. Depth is defined by what we were discussing and no matter if I used a cropped sensor or a full sensor, depth will not change.

 

[Village Idiot]

That pretty much supports what I said.

What you misunderstood is that a sensor cropped or not shows width, not depth. Depth is defined by what we were discussing and no matter if I used a cropped sensor or a full sensor, depth will not change.

In many cases, the DOF is fixed by the requirements of the desired image. For a given DOF and field of view, the required f-number is proportional to the format size. For example, if a 35 mm camera required [FONT=Georgia,serif]f/[/FONT]11, a 4×5 camera would require [FONT=Georgia,serif]f/[/FONT]45 to give the same DOF.

A Canon 5D with an EF 50mm f/1.8 will not have the same DOF at f/4 as a Canon 40D with the same lens at the same f stop. The 40D would need a 40mm lens to have an almost equivalent DOF.

The crop factor changes the DOF by changing the FoV. Lenses at a greater focal length have less DOF than a lens at a close focal length. shoot a 70-200 @ f/4 @ 200mm then shoot a 10-22 @ f/4 @ 10mm. The 10-22mm lens shot will have a much greater DOF than the 70-200mm lens shot.

A calculator: http://www.dofmaster.com/dofjs.html