Unsure about how to do this...

[seanreed]

At the end of this week, I'll be at an event where I can photograph some helicopters that will be displayed (grounded, no action shots). I've had some DOF problems in the past, so I wanna get all this straight before I actually go out there... I'm trying to avoid bring a tripod out, but can I achieve a good DOF if I'm relatively close to it? If so, any recommended settings? The pictures I want to be be able to take are going to have the helicopters at an angle where the cockpit is closest to me, and the body of it will be further back, increasing as you get to the tail.

I'll be using a Rebel XT.

Thanks guys... been helpful in the past, hoping someone will help again!

--Sean

[Rhinotherunt]

There is a DOF calculator on the internet, but I do not have the link. With wider lenses DOF is greater. If it is sunny use F8 and you should have a pretty deep DOF with medium range lenses.

[Vini]

Here it is

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

[Titus213]

DOF is primarily a function of the lens you will use. If you have the kit lens you may encounter some difficulty obtaining shallow DOF because your max aperature is 3.5. If you are trying to get maximum DOF that is easier to accomplish - crank up the f-stop (add ISO as needed to keep shutter speed up).

[seanreed]

DOF is primarily a function of the lens you will use. If you have the kit lens you may encounter some difficulty obtaining shallow DOF because your max aperature is 3.5. If you are trying to get maximum DOF that is easier to accomplish - crank up the f-stop (add ISO as needed to keep shutter speed up).

If I'm understanding everything correctly, I want the entire helicopter to be sharp, so that'd be maximum DOF, correct?

--Sean

[Rhinotherunt]

If I'm understanding everything correctly, I want the entire helicopter to be sharp, so that'd be maximum DOF, correct?

--Sean

Yeah, bigger number = smaller aperture = bigger DOF, but one must not forget diffraction. ;)

[seanreed]

Yeah, bigger number = smaller aperture = bigger DOF, but one must not forget diffraction. ;)

Now you're just trying to confuse me! :lol:

Thanks a lot for in the info, maybe I'll post some pictures when I'm done!

--Sean

[Rhinotherunt]

Now you're just trying to confuse me! :lol:

Thanks a lot for in the info, maybe I'll post some pictures when I'm done!

--Sean

What part is confusing?

Set you camera to AV, make the F - stop # between 8 and 11, and use ISO 200 or 400.

Higher F# = Smaller Aperture = Deeper DOF
Lowerr F# = Wider Aperture = Shallower DOF

Diffraction is (basically) loss of sharpness beyond F-11...

[seanreed]

What part is confusing?

Diffraction is (basically) loss of sharpness beyond F-11...


Never heard of "diffraction" in terms of photography. So, that was the confusing part. Thanks!

--Sean

[CorruptedPhotographer]

There is a DOF calculator on the internet, but I do not have the link. With wider lenses DOF is greater. If it is sunny use F8 and you should have a pretty deep DOF with medium range lenses.



DoF does not change with focal length. It only changes with adjustments to aperture and distance of subject from lens.

People think that longer lenses have greater DoF. Thats not true, they (tele lenses) appear to have greater DoF because you have backed up (foot zoom~physically) in order to achieve the same composition as a wide angle lens, which follows my above point, you have increased the distance of lens from subject, hence increasing DoF.

[Rhinotherunt]

Teles have less DOF than short lenses... A 10mm will have a deeper DOF than a 200mm at the same aperture. Try it out...

[Rhinotherunt]

Never heard of "diffraction" in terms of photography. So, that was the confusing part. Thanks!

--Sean

Link on diffraction:
http://www.cambridgeincolour.com/tutorials/diffraction-photography.htm

[CorruptedPhotographer]

Teles have less DOF than short lenses... A 10mm will have a deeper DOF than a 200mm at the same aperture. Try it out...



I did, and I urge you to try it out. :)

Maintain Distance from subject and aperture, switch lenses from wide to tele and lets see if DoF changed.

Again, the focal length of a lens has nothing to do with DoF.

DoF is strictly altered by aperture and distance of lens from subject.

[Rhinotherunt]

I did, and I urge you to try it out. :)

Maintain Distance from subject and aperture, switch lenses from wide to tele and lets see if DoF changed.

Again, the focal length of a lens has nothing to do with DoF.

DoF is strictly altered by aperture and distance of lens from subject.

Here is what the #'s say:

[Hermeto]

Shoot with f/8 and you'll be OK with DoF..

[Rhinotherunt]

Here is one more...

[CorruptedPhotographer]

Im sorry you are not totally incorrect.
Wider lenses do have greater DoF at given distance and aperture, but DoF is also directly affected by distance and aperture. Use a macro and see.

Also, I mistook perspective for DoF.

See this link
http://www.dpreview.com/learn/?/Glossary/Optical/Perspective_01.htm

[dmp-potn]

Hello,

I did, and I urge you to try it out. :)

Maintain Distance from subject and aperture, switch lenses from wide to tele and lets see if DoF changed.

Again, the focal length of a lens has nothing to do with DoF.

DoF is strictly altered by aperture and distance of lens from subject.

According to the popular web DoF calculator (http://www.dofmaster.com/dofjs.html):

24mm lens, f/2.8, 20 ft. from the subject = DoF of 179.00 ft.
400mm lens, f/2.8, 20 ft. from the subject = DoF of 0.12 ft.

Are you sure that you're not talking about maintaing the same framing and aperture rather than distance from subject?

[dmp-potn]

Hello,


Also, I mistook perspective for DoF.

See this link
http://www.dpreview.com/learn/?/Glossary/Optical/Perspective_01.htm

No arguments there. A zoom lense won't change your perspective. You actually have to get up out of that lounge chair and move around. :-)

Peace,

[Rhinotherunt]

Also, I mistook perspective for DoF.

See this link
http://www.dpreview.com/learn/?/Glossary/Optical/Perspective_01.htm

Yeah, DOF and Perspective are two quite different things.