Question by Monicaaaa: Question about digital camera and aperture?
I love on a regular camera, the aperture, where the background is blurry and the subject is in focus. I want a digital camera that does that. So how many mega-pixels do i need? Or is there something that i should look for while trying to buy a digital camera?
Thanks !
Best answer:
Answer by birdbackg
First, the aperture is hole on a camera that opens to expose the film, the aperture setting determines how far this hole will open. Aperture settings will give more or less depth of field. Depth of field is the distance range of what will be in focus. A small depth of field is what is what creates the effect you are talking about. I would bet there is a way to do this in some point and shot digital cameras, though different models may call it different names. What you want is a digital SLR, or single lens reflex. This will give you all the creative control you are used to on you film camera, which i assume is an SLR. Mega-pixels are irrelevant to ,your question, but any digital SLR will have enough for your purposes unless you are wanting very large prints. Have fun and keep shooting.
What do you think? Answer below!
It has nothing to do with – Mega Pixels – but a function of the camera it’s self…
You would need a lens that is kinda fast, a f/2.8 would be nice. However, you can also do what you ask with a zoom lens as long as you have some way to control the camera’s aperture.
Just the fact of zooming in on something that is 10 ft (or so..) away, the background will go fuzzy, if not to close. The idea of shooting with a wide open f/stop can help a lot too, or as wide as the camera can do and correct the exposure with shutter speed and/or ISO settings.
If you want this in a digital camera, get one with as many manual controls as you can. Full shutter speed and F/stop control..! There are a # of D-SLR kits around $ 500 now and a # of “bridge” cameras too, they look and act like a D-SLR but their lens does NOT come off and many have humongous zooms you can’t get on a D-SLR..
Nikon D-40 or the Canon Digital Rebel are 2 good choices…
Bob – Tucson
Megapixels has nothing to do with it.It’s the physical size of the lens opening that creates the depth of field. To get a shallow enough depth of field so that the background of a normal portrait shot is out of focus, you probably need one inch (25mm) or more of lens aperture. The physical aperture is the focal length of the lens (the real focal length, not the 35mm equivalent) divided by the f-stop. So a 50mm f/2 will do a reasonable job wide open; fast short telephotos, 135mm f/2 or 2.8, for example, are even better. In a digital camera, a DSLR with a reasonably fast 50mm or longer lens will do a nice job of giving you good out-of-focus backgrounds. Just remember to shoot wide open or close to it, and use the depth-of-field preview if the camera has it.
The Nikon D40 has the feature of where you can manually set the aperture and shutter speed. Other DSLR’s can do this as well.
Depth of Field (DOF) is defined as that area that is in acceptable focus in front of and behind the subject.
On a 35mm film camera or a full-frame sensor DSLR, DOF is purely a function of lens focal length and the f-stop chosen. With compact digital cameras and regular DSLR cameras the sensor also enters into the equation, especially the tiny sensors used in the compacts. The much larger sensor of a non-full-frame DSLR will make using DOF as a creative tool much easier.
Here are some examples based on a 35mm (24mm x 36mm) frame.
21mm lens at f2.8 and focused to 1′ : DOF is from 11 1/2″ to 1′ 0 3/4″
21mm lens at f2.8 and focused to infinity : DOF is from 16′ 3″ to infinity
21mm lens at f16 and focused at 6′ : DOF is from 2′ 2″ to infinity
21mm lens at f16 and focused to infinity : DOF is from 3′ 1 3/8″ to infinity
100mm lens at f2.5 and focused to 4′ : DOF is from 3′ 11 3/8″ to 4′ 0 3/8″
100mm lens at f2.5 and focused to infinity : DOF is from 394′ to infinity
100mm lens at f16 and focused at 6′ : DOF is from 5′ 8 1/2″ to 6′ 6 3/8″
100mm lens at f16 and focused to infinity : DOF is from 43′ 10″ to infinity
DOF is much more difficult to achieve with a compact digital camera due to its tiny sensor.
Expo Imaging (http://www.expoimaging.net) offers the ExpoAperture2 which is a DOF calculator. Its very useful and easily portable and will show you the DOF at different combinations of focal length, f-stop and focusing distance.
For the most creativity with DOF a DSLR would be your best choice.