Aperture Ring for Canon EOS

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Well I've started my collection of lenses for my 20D and have noticed something, or the lack thereof. Does Canon offer any lenses with an aperture ring on the lens barrel, or more importantly, focus markings. My friends old manual Canon film camera had those oh so important markings around the aperture ring so you could quickly figure hyperfocal distance and the such. So far, the only lens I have that offers something of the like is the 70-200 L, but even that doesn't have a quick way to figure hyperfocal distance. My 75-300 lacks such markings and is quite annoying when manual focusing at night or low light situations. Is there a trick that anyone knows to help me in my quest for focus. O yeah, I know, I'll use that new improved version camera with auto-zoom and auto-focus...how's it go again?, right *Camera, Go Focus Mode NOW*

Thanks for any help or comments, or random distractions, or advice
 
You're in for a dissapointment.

1) only L glass has such markings. Most of the lenses have f/11 and f/22 at best.

2) the hyperfocal distances marked on 35mm lens are designed with full frame cameras in mind. They're gonna be different/shifted on 20D

Cheers
 
2) the hyperfocal distances marked on 35mm lens are designed
with full frame cameras in mind. They're gonna be different/shifted
on 20D
no change for a digital camera - the distance is still the same,
the DOF might be different due to the smaller size of the sensor
(compared to full frame 35mm)

//edit:
anyhow, focus the AF lens to a known distance and mark it
with tape or a Sharpie - in this way you're still able to use
it as a 'manual' lens...
 
doxx said:
no change for a digital camera - the distance is still the same,
the DOF might be different due to the smaller size of the sensor
(compared to full frame 35mm)
You contradict yourself.
 
DocFrankenstein said:
doxx said:
no change for a digital camera - the distance is still the same,
the DOF might be different due to the smaller size of the sensor
(compared to full frame 35mm)
You contradict yourself.

I'm totally confused about this too. My intuition says that DOF and hyperfocal distances don't change, because the sensor only imposes a 'crop' which doesn't change anything optically... but then a friend pointed out that you're also going to be magnifying that crop somewhat, so that you need slightly better focus in order for something to be 'acceptably sharp' - you get a magnificiation effect, basically reducing your DOF slightly... although with this logic, DOF would relate to your expected print size (or the resolution / grain of your sensor or film)...

Still need to go read up on it a bit sometime.
 

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