What is Depth of field?

[Poseidon]

Here is the best way I can show you... PLease excuse my Typo's, the first # represents the F-stop, the second # the shutter speed. All of these were taken with a tripod, a 70-200 f2.8 lens, and my 500D close-up filter. THe filter REALLY exxagerates the depth of field, so it made the examples even easy to tell apart. I will start with the smallest apeture, and work my way to the largest. So f32 first, f 2.8 last...












Hope this helps.... Next I will show Noise and ISO...

[Reefland]

Oh man that is an excellent visual representation Mike. So here what we have is the lower the F-Stop with Higher S, the less out of focus the entire picture becomes.

*Mental Note For Scott:
When shooting in manual go for high F and low S.

[zhenya]

*Mental Note For Scott:
When shooting in manual go for high F and low S.

And use tripod... At the largest f# the aperture is the smallest and will need lots of time to have enough light to pass through it to the sensor, so I don't know who can hold camera still for this long... Can you, Mike?

PS. Nice visual, Mike. I think I never shoot anymore with less than f8, all you see is a small dot in focus if you use 3.5 on my macro lens.

[Reefland]

Got it!

*Mental Note For Scott:
When shooting in manual go for high F and low S.
And use a tripod.

[Poseidon]

Hehe...

I can hand hold down to 1/15 SOMETIMES... depending on which lens, and what focal length...

Scott that trick only works for pictures of corals, a fast moving fish will kill your "high f and low s" mental note...

[tatuvaaj]

Scott that trick only works for pictures of corals, a fast moving fish will kill your "high f and low s" mental note...

Unless he's extremely good at panning

[rab3rd]

Oh man that is an excellent visual representation Mike. So here what we have is the lower the F-Stop with Higher S, the less out of focus the entire picture becomes.

*Mental Note For Scott:
When shooting in manual go for high F and low S.

Close, think of the point of focus as being a sheet of glass running vertically through the subject. This is called the focal plane and it is parrallel to the sensor or film plane. Depth of field is defined as the area in front of and behind the focal plane that is in focus. The more you open the lens (lower F stop) the less area that will be in focus in front of and behind the focal plane. Typically 1/3 in front of the focal plane and 2/3 behind the focal plane. The speed is not related to the depth of field or focus but the exposure level (brightness) of the picture and the ability to freeze motion.

I have a 100mm macro lens that has a silly dof opened up all the way when focusing at a 1:1 distance. the dof is about an 1/8th of an inch

My other hobby is photography by the way ;)

[Bn251]

This is soo much help thanks Poseidon!

[mcoleman]

Aside from having interest in this field, I am also much interested with image processing. Currently, I am looking at depth perception with computer and hardware. This topic would deal with gauging the level by which objects are in, with a picture.

It basically detects which object comes first and which follow leading to the background. It will be very essential to underwater photography actually. I will be sharing updates on it as things progress.

[rafaelagee]

I think these kind of visual will help to everyone as they want. Buy the way...Thanks Pose......