Hyperfocal distance and autofocus lenses

[Tom Camilleri]

Do I need a manual focus lens to set focus at hyperfocal distance? If so, which is best for digital Rebel?

I have three lenses presently: 18-55mm EFS kit lens, Canon 50mm macro EF, Canon 75-300mm zoom EF. None of these auto-focus lenses seem to offer a way to focus at the hyperfocal distance. Do I need a manual focus lens with a depth of field scale to do this? If so, what lenses should I be looking at?

[Brian Burns]

See if this helps:

http://dofmaster.com/custom.html

Also, there are some lenses that have dof scales on them that are AF. The 24L and 35L come to mind.

[Tom Camilleri]

See if this helps:

http://dofmaster.com/custom.html

Also, there are some lenses that have dof scales on them that are AF. The 24L and 35L come to mind.


Unfortunately, there is no Mac version of the program : (. Thanks for the link just the same.


My Canon 50mm compact macro and my Canon telephoto do have depth of field scales, but I don't see how I can set them to exploit hyperfocal distance. A book I'm reading instructs how to focus for maximum DOF for a manual focus lens as follows:

1) Set f number to highest possible.

2) Set distance according to main area of interest.

3) Using DOF scale, turn focus ring until infinity mark lines up with appropriate f number mark on DOF scale.

WIll it always be possible to line the infinity mark up with the appropriate f number bracket on a manual focus lens, or is the course I'm reading describing taking a shot where the background is actually at infinity? How would one duplicate this technique on an autofocus lens.

[Tom W]

There's a couple of issues with lenses that will prevent you from doing this - many autofocus lenses do not have a distance scale.The 18-55 kit lens and the 75-300 zoom are such lenses. On the other hand, most of Canon's prime lenses do have a distance scale, and the mid-priced and "L" zooms do as well. The 17-85, for example, has a distance scale.

What's missing even on the zooms that do have a distance scale however, is the DOF/f-stop markings, reason being that this characteristic changes as the lens is zoomed from wide to telephoto. Prime lenses have these markings, and in general, the wider the lens, the farther apart and more useful the markings are.

[eastcoast909]

Ok, I understand that the kit lens does not have any markings.....

but, what if I do something like this?

at 55mm the hyperfocal distance of the lens should be 58.3 ft (taken from http://dofmaster.com/dofjs.html)

If I then focus the lens using af at an object at this distance, switch to manual focus and don't adjust the lens then it still should be at the hyperfocal distance for this length.

You should also be able to do the same using the FE lock function. Focus at the estimated hyperfocal distance, keep the shutter button half depressed and recompose your picture, then take you picture.

You might have to use AE first on your scene to achieve the desired exposure for your scene if the lighting is different from the point where your take the focus for the hyper focal spot.

I think that this should work, but have never tried it. You can also try the ADEP function.

Anyone else? Please correct me if I have the wrong understanding of this.

[Scottes]

Yup, focus on something at the correct distance and flip the lens to MF. That's all that's necessary.

I kinda wish the camera would automatically set the hyperfocal distance for the given lens and aperture. The camera has all the info - focal length and aperture, right? Why not have the landscape mode automatically set the hyperfocal, too? Then you could flip to manual focus, manual mode and fire away.

[jfrancho]

Unfortunately, there is no Mac version of the programThen use the online version: http://www.dofmaster.com/dofjs.html

[buze]

I wrote one for mac some time ago, but never released it. I have no idea if there is any interest for it..
http://oomz.net/dofc.png