Does a wide angle lense effect the depth of feild at all???????

This should have gone in your other wide angle lens thread....

Anyway, I believe it widens the DOF but I'm not sure. That's just the impression I get.

yes it does. The wider the lens the bigger the depth of field compared to other lenses from the same distance to the object

yet, I believe the main factor for depth of field (besides the aperture) is the size of the object in the frame. Frame a head with a telephoto lens and get exactly the same frame with a wide angel lens and the depth of field should be the same. I man be wrong about this but I heard it from several sources before

I thought DOF was how wide the area in focus was. For example, a macro closeup has a very shallow DOF and the area in focus is often only about an inch of distance (measured away from the lens) where as a wide shot has a DOF of dozens of feet.

Wider lense bigger depth

now I am really curious about it. Of course wider lenses have bigger depth of field...but probably nota could help out here.

say I use a 85mm lens (35mm) and frame a standart close up. Then I use a 25 lens and frame the exact same close up (I move the lens real close to the subject. I believe the depth of field should be the same. Therefore, it is questionable if really the focal lenght makes the difference in depth of field.

Never tried it, I just remember my cinematography teacher at NYU said so

Yeah.... I never thought of that. I'm going to test this out with my still camera I think... I'll let you know what happens!

I think you'll find it does .. . . but not as much as the size of the imaging plane, distance to subject, or the aperture.

I was going to do some still tests too! I have a few lens' that are zooms and are f2.8 across the zoom range so the DoF should stay constant (and small!).

Ok, here's a quick experiment I did with my manual still camera. While I don't know the lens mm sizes so I can't be exact, it does seem to indicate that the DOF is markedly wider even on low F numbers with the wider lenses.



(ps - sorry about the grain, 400 ISO, ugh)

haha thanks that helped a lot.

quote:

Frame a head with a telephoto lens and get exactly the same frame with a wide angel lens and the depth of field should be the same. I man be wrong about this but I heard it from several sources before

No...

The main factors influencing DOF are focal length (related to imaged area) and aperture. This is the reason why a "film-like" DOF is nearly impossible to achieve with most DV cameras - the CCDs are so small that the focal range is very large, flattening the image.

hehe I got something wrong, obviously

shame on me )

Those pictures were really helpful! Did you take those with a digital camera, or on a 35mm SLR and develop them just for us?

It was a fully manual digital camera. The Canon Powershot A80. A decent little consumer model, created before they ruined the Powershot series.

By the way, I just order a Rebel XT!! I'm so excited!

quote:

Originally posted by titaniumdoughnut:
By the way, I just order a Rebel XT!! I'm so excited!

Nice, it's a great cam. I'm looking for an excuse to upgrade to that from my 300D, but I sort of have an addiction to lens' that keeps my photography budget spoken for pretty quickly.

I will fall prey to the same addiction now that I'm getting a camera worth buying lenses for. It's coming with a telephoto lens, and some kind of cheap looking wide angle adaptor, but I'm sure I'll be going nuts to get more glass pretty soon.

so from what i remember:

it doesn't matter what framing you use, wide angle lenses give you more depth of field because of the glass used to make it a wide angle lens. it affects the light rays entering the lens differently than a telephoto lens.

a telephoto lens has more glass in it, so it will give a softer picture than a wide angle, and less depth of field.

a zoom lens will give an even softer picture and might even give you elss depth of field than an equal prime lens, depending on how it's put together.

it has to do with the light bending inside the lens by way of the lenses, and the focal plane.

DOF is also made narrower by wider apertures and lower F stops.

yes, the aperature affects focus because the smaller the opening of the aperature, the less light rays come into the focal plane: the less light rays, the less chance of those light rays being out of focus.

man i should make some diagrams or something because i was trying to explain this to my friend in another state, because he's trying to figure out how he could make some solid aperature plates for his medium format stil camera. i don't think it would even work for medium format, maybe large format. hm.