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Depth of field 
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Joined: Thu Apr 23, 2009 6:54 pm
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Right.

I'm a bit of a n00b when it comes to photography.

There, first bit over.

I need a bit of a hand. I like macro pictures, especially of tech, however I'm struggling with the small depth of field my camera seems to have(?)

I'm using a crappy point and shoot at the moemnt, but am looking at getting a Nikon D60.

Taking this image as an example:
Image

If the depth of field was larger the area in focus would be larger, am I correct?

Any tips on how to 'work' the camera so the DoF is larger then and more of the image is in focus? I'm guessing the camera probably isn't the best for the shots I'm trying to get.


Sat Jul 11, 2009 9:07 pm
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Yes, if the DOF was larger, there would be more in focus.
I don't know how manual your camera will go, but generally, the larger the aperture the smaller the DOF.
So, what you want to do is to close down the aperture - this will likely lead to a longer exposure time.
Ultimately, the DOF is dependant on your lens, so you're stuck with whatever your camera can do.

FWIW, I quite like a tight DOF. Most of my stuff is shot with the aperture wide open.
On my 45mm lens, it's just crazy. I took it out to a birthday dinner thinking it'd be good discipline to just use one lens for the evening. Because the light was so low, I had to open the lens right up, which of course meant the DOF was really narrow.
Made composing the shot more challenging than if I'd been on my 28mm or 50mm. The 45mm just seems less forgiving. Good practice though. :)

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Sat Jul 11, 2009 9:45 pm
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Depth of field is dependent on both focal length and aperture. Wide angle lenses will have a greater depth of field than long lenses and as noted, smaller apertures means greater depth of field and of course, longer exposures.

The overall depth of field extends around two thirds of the distance beyond the focal point and one third of the distance towards the camera. In other words, if you wanted to include three objects that were positioned as shown below-

2m away---------------------------------2.33m away------------------------------------------------------------------3m away

You would focus on the object 2.33m away and providing that your aperture was set accordingly, you would get all three objects in focus. If the aperture was too large, then you could focus on the object 2.33m away, but the depth of field might only extend 24cm beyond the object and 12cm towards the camera.

In this case, if you focussed on the most distant object- 3m away, then your overall depth of field to get all three objects in focus would need to be 3m- 1m towards the camera and 2m beyond the object.

Depth of field is also affected by the distance between the object and the camera. With identical settings on the camera, you will get a shallower depth of field if the object is closer to the camera. This is why macro photography has a very limited depth of field. For static subjects like your Samsung product, you can mount the camera on a tripod, close down the aperture and take a long exposure, but for living subjects, such as bees or butterflies, you are going to have to be fast, and that means wide open apertures and shallow depth of field.

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Sun Jul 12, 2009 10:37 am
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