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Ruahrc

macrumors 65816
Jun 9, 2009
1,345
0
I'd say "proves my point!" here, since you haven't had to work out how to do it, you can't imagine doing it.

Care to elaborate how? The only way I can figure is once you know the hyperfocal distance, you must find some object at said distance, AF on it, and lock the focus down using MF mode. But that is why I said "practical" as unless you have a tape measure in your camera bag....

Ruahrc
 

compuwar

macrumors 601
Oct 5, 2006
4,717
2
Northern/Central VA
Care to elaborate how? The only way I can figure is once you know the hyperfocal distance, you must find some object at said distance, AF on it, and lock the focus down using MF mode. But that is why I said "practical" as unless you have a tape measure in your camera bag....

Ruahrc

Essentially, that's it (though you don't need to AF, you can MF all the way)- it's just like rifle shooting or golfing- you go with either a known distance object, or you estimate distance. Just like with the other two disciplines, it's one of those things that requires practice to get down- pretty-much all unknown distance rifle shots work exactly the same way- yet somehow many people find it perfectly practical to take an unknown distance shot even though they not only have to deal with distance estimation, but humidity, wind, altitude, bullet drop, concealment and even incoming fire.

You can also use the focus point indicators and their spacing in the viewfinder similarly to mil dots in a scope's reticle to determine the distance to a known or estimated size object- though this requires a bit of up-front work, it's a *very* workable solution to commonly sized objects- and mostly we're shooting commonly-sized objects such as people, cars, pets, wildlife... So, if I know that a 6' person is 1 a focus point tall at 50 yards and 1/2 a focus point at 100 yards, then if I have a person who's 3/4ths of a focus point tall, I know they're at 75 yards, a little less, they're a little further, a little more they're a little closer.

You don't have to deal with wind, hold over/under or bullet drop- or wind and ball lie if you prefer- so it's even easier than either of the alternative examples. People who've never shot a scoped rifle with proper instruction also think it's pretty impossible and impractical to shoot a target at an unknown but relatively long distance while those who've had the training understand that it's just a matter of practice, practice, practice.

As far as your definition of practical, I'll again have to disagree- for instance, let's say I have a D3x with a 70mm lens, I know that f/11 is inside my diffraction limit, so I'll go for f/11- my trusty DoF calculator tells me that at 30 yards, my near limit is 31.1 feet and I'm good to infinity from there. WIth a 400mm lens, I know the same shot gives me a near limit of 85.1 feet and my far limit is 95.5 feet. If I do it regularly, I can generally get within the margin of error with the camera and the rifle (though the rifle requires more work and more data,) I'm still working on the golf clubs.

If I'm distance-estimating challenged and I haven't calculated my target size and the size of my AF points at distance, then I can simply carry a rangefinder in my pocket, or consult a GPS or use a correctly scaled map. All of those options give you the ability to pre-focus and get good results, distance scale or not.

For examples of ranging with a mil-dot scope, see http://www.shooterready.com/mildot.html
 

Wakakanada

macrumors regular
Oct 21, 2007
149
7
Vancouver, BC, Canada
Buy it! ...I did.

I'm in the same boat as you. Complete DSLR newbie. After doing all the internet research and holding the cameras in store, I went with the T1i. The Nikon 5000 made sense too. In the end they are all going to be good enough, I wanted LiveView otherwise I might have considered the soon to be released Nikon 3000. I'll use the video too as I don't think I will continue to pack two camera's with the size of these DSLR's !!!
 

akdj

macrumors 65816
Mar 10, 2008
1,186
86
62.88°N/-151.28°W
Compuwar,

You totally remind me of my Photography teacher in High School;) LOL! It's awesome though, I certainly see your position (pun intended)...

I think the basics are smart to learn....BUT, in defense of Ruahrc, I see his point. The AF systems are advanced on these new DSLRs...some, better than others. Hopefully Canon nailed it this time (7d) devoting an entire processor to the auto focus system, but even without it....AF has come a LONG way in the last 20 years and 10 in digital. Agreed, there are times, especially with fast lenses, limited DOF, and the "Magic" shots for the showrooms...MF will come into play. And SHOULD be learned! My wife is learning and was shooting with me last weekend on a 28-135 when the AF motor died...it can happen, BUT, more often than not...for a beginner, the AF system is going to work. Training wheels are abundant on the DSLRs these days....from the little Green Box to Live View to AWB, it's all there and makes it pretty easy for a newbie to pick up the hobby. It's also there for those of us that want the convenience of shooting "Run and Gun" style (Or is that too "Video?:)") and are lazy....I, too, focus and recompose because of the "Old days" of AF systems...

...and although it's been 20 years next spring since my Senior Year in High School...>Compuwar brings back some fine memories.....

You WILL learn your MF system or ELSE!!!!! (kidding;)

Peace
J
 
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