Depth Of Field

[Kirislin]

I know this isn't a great photo, but it will serve the purpose well for my question. What I was hoping for was to have the birds clear and sharp and the foreground and background out of focus. I thought with an aperture of f3.2 I would have got that, but I haven't. The birds seem reasonably sharp to my eyes (which aren't too good BTW) but I haven't got the shallow depth of field I was after. Yes Feather in the foreground is OOF and so are the trees a bit, but not as much as I wanted. Can some experienced photographer help me understand why. Would it have had more of the effect I wanted if I was lower to the ground, I was standing when I took it, I'm wondering if it's got to do with plane of view, dont know if that's a photographic term or I just made it up, I hope people understand what I mean.

*edit, I think I meant focal plane

Edited June 3, 2010 by Kirislin

[SoL]

Is it bokeh you're after or is that another matter entirely? Sorry, no help obviously but I'm curious to know the answers as well

[becandcharch]

Im not 100% sure this is correct but I think you are trying to fit too much in to get a shallow dof.

I use a larger apperture for closer objects to get shallow dof. More for portrait style?

I think if you got down lower you may have just gotten the dog in focus as he/she is closer.

Again this may be wrong though

[anniek]

To me you need the "subject" very close to the camera, and a big distance between the "subject" and the background?

[Kirislin]

3.2 is a fairly large aperture and the camera pretty much got focus on the birds, which is what I wanted. Annie you might be right in that it has to be closer but I am not sure. I've seen photos where the focus point is further away. like the birds, but still has a very shallow depth of field so in front and behind are out of focus.

I have in my mind a couple of pics I've seen on POTN but a long time ago and I wouldn't know how to find them now. One was of a magnificent tree in the distance but all before and after it were OOF. The other was of people, just the ones he wanted were in focus but again all before and after were OOF. Maybe it's done in PP. I hope not.

Edited June 3, 2010 by Kirislin

[becandcharch]

3.2 is a fairly large aperture

I think this would have worked if you only wanted one or two birds in shot and they were closer. I know when I take shots of the 2 dogs sitting side my side I have av set at about 5

Maybe the shots you saw had been edited kirislin

[Kirislin]

3.2 is a fairly large aperture

I think this would have worked if you only wanted one or two birds in shot and they were closer. I know when I take shots of the 2 dogs sitting side my side I have av set at about 5

Maybe the shots you saw had been edited kirislin

Mmmmm, not sure. I had it focussed on just one using spot auto focus but even so, if the birds were all at relatively the same distance from me, imagine they are all glued to a pane of glass so all at the same depth of field I though it would still isolate them from the things in front and behind.

[Ripley]

What you describe you saw in photos could have been achieved by 'focus stacking' which is achieved in PS apparently.

Have a google about it.

Not sure what you want to achieve in that shot? Did you just want it all in focus?

[macka]

get closer to the birds and shoot at 1.4-1.8

[SchnauzerBoy]

DOF is quite an art, and most of what others have said on here is correct.

The correlation though is between your aperture, the distance to the subject and then the distance to the background.

As AnnieK has said, if the birds were close to you and you had the f3.2 set, you would have had a much shallower DOF meaning the background would have been softer, more OOF and with some Bokeh.

Not sure on the settings of your shot, but might be worth using the DOF calculator to see what would have been in focus.

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

From there you can then work out the Bokeh to remove the background, but basically you would have had to be closer to the birds, have a lower f stop and the background be further away. Distances are the key

[becandcharch]

DOF is quite an art, and most of what others have said on here is correct.

The correlation though is between your aperture, the distance to the subject and then the distance to the background.

As AnnieK has said, if the birds were close to you and you had the f3.2 set, you would have had a much shallower DOF meaning the background would have been softer, more OOF and with some Bokeh.

Not sure on the settings of your shot, but might be worth using the DOF calculator to see what would have been in focus.

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

From there you can then work out the Bokeh to remove the background, but basically you would have had to be closer to the birds, have a lower f stop and the background be further away. Distances are the key

Pretend I said that

[anniek]

DOF is quite an art, and most of what others have said on here is correct.

The correlation though is between your aperture, the distance to the subject and then the distance to the background.

As AnnieK has said, if the birds were close to you and you had the f3.2 set, you would have had a much shallower DOF meaning the background would have been softer, more OOF and with some Bokeh.

Not sure on the settings of your shot, but might be worth using the DOF calculator to see what would have been in focus.

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

From there you can then work out the Bokeh to remove the background, but basically you would have had to be closer to the birds, have a lower f stop and the background be further away. Distances are the key

Pretend I said that

good lord - I think I did say that, well sorta

[Kirislin]

OK, it's just that I feel like I've seen pics with the main subject further away and still with the shallow depth of field. If I ever find one I will post it here.

[kja]

DOF is a function of distance as well as aperture.

The farther you are, the greater the DOF.

It's also the lens - wider angle lenses will give you apparently greater DOF at a similar distance than say a nice long lens.

Oh, and quick rule of thumb is 1/3 in front and 2/3 behind your main subject.

Edited June 3, 2010 by kja

[Linda K]

was also going to say a big factor is also the lens - a 50mm or telephoto lens is a lot easier to work with to get that bokeh than a wider (say 35mm) - that is where I love either my 85 or 135 o my full frame camera. Also depends where you have focused in this picture too. A good way to see what effect you are going to get with your picture is to use the DOF preview button on your camera if it has one - on the Canon it is on the front, and that will then give you a view through the viewfinder of the shot as being seen at the current aperture the camera is on - that will let you know if you need to finetune it before you take the shot. other than that, just practice with each lens using a stationery object at varying distances to the background, and apertures, and you will very soon learn what will give yo the effect you want

[Kirislin]

It was with my 50mm. I can never seem to see the difference with the DOF preview button, I probably wouldn't have had time to use it though.

[altheau]

I can never see changes with the DOF button either, and I have always wondered if I am doing something wrong.

[Kirislin]

I can never see changes with the DOF button either, and I have always wondered if I am doing something wrong.

Oh good, I'm glad it's not just me.

[Linda K]

What you should see is it goes dark, and you see a view through the viewfinder of what you are going to get, it does take a bit f practice though to get used to. How close were ou to what you were photographing, and where were you focusing? When I am trying to do what you were, I would be of preference using at least the 135mm lens, on F2, and would be about 7 foot from my subject - with the 50mm, I would be a lot closer, say 2-3 feet at most.

[Kirislin]

From what everyone says it looks like I cant get that effect from the 50mm and the distance I was at. It doesn't matter, it was really just a spur of the moment thing when she ran at the birds, not much I could've changed in the circumstances.