Understanding Exposures not Understood

RxForB3

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I'm currently reading Understanding Exposures (as recommended by many of you). So far I can't say I enjoy the author's writing. He seems very pompous, but then, that could just be me. Plus, while it felt like the beginning of the book was all about learning to shoot on manual, he VERY often states that he shot on aperture mode. AND despite his insistance on the "triangle," he seems to almost completly ignore ISO. I might not be to that section, though, I suppose. In any case, I've gleaned a few ideas to try, but there are at least a couple things I don't think he suitably explained (or I didn't understand them, or he will explain later).

First off, he keeps saying in reference to his photos that he pointed the camera to the sky (or some other portion of the photo), got the appropriate shutter speed for the aperture, then recomposed the picture. Maybe I should reread my manual, but I don't recall it saying specifically how to do this. Do I press the shutter halfway, hold it, frame the shot and go? If so, that doesn't seem too practical when using a tripod...

Second is the idea of how to focus with a large aperture (he uses f/22 a lot) such that everything is in sharp focus. He mentions setting the distance on the lens to 2 ft. or some such. However, on neither of my kit lenses do I see a designation of distance (nor, if I recall is there one on my 50mm f/1.8). First off, how does one determine which distance to focus with each lens (he gives only two examples with no explanation of how he came up with that), and second, without a distance option, how does one do this? I tried today while on my outing in Yakima Canyon (see my other post) and failed miserably.

Thanks for your help!
 
I'm currently reading Understanding Exposures (as recommended by many of you). So far I can't say I enjoy the author's writing. He seems very pompous, but then, that could just be me. Plus, while it felt like the beginning of the book was all about learning to shoot on manual, he VERY often states that he shot on aperture mode. AND despite his insistance on the "triangle," he seems to almost completly ignore ISO. I might not be to that section, though, I suppose. In any case, I've gleaned a few ideas to try, but there are at least a couple things I don't think he suitably explained (or I didn't understand them, or he will explain later).

First off, he keeps saying in reference to his photos that he pointed the camera to the sky (or some other portion of the photo), got the appropriate shutter speed for the aperture, then recomposed the picture. Maybe I should reread my manual, but I don't recall it saying specifically how to do this. Do I press the shutter halfway, hold it, frame the shot and go? If so, that doesn't seem too practical when using a tripod...

Second is the idea of how to focus with a large aperture (he uses f/22 a lot) such that everything is in sharp focus. He mentions setting the distance on the lens to 2 ft. or some such. However, on neither of my kit lenses do I see a designation of distance (nor, if I recall is there one on my 50mm f/1.8). First off, how does one determine which distance to focus with each lens (he gives only two examples with no explanation of how he came up with that), and second, without a distance option, how does one do this? I tried today while on my outing in Yakima Canyon (see my other post) and failed miserably.

Thanks for your help!

Predict the distance. But I do recommend you to use auto focus to set the focus point. I've missed lots of photographs by shooting by locking my focus via manual focus and lost focus after changing the focal length.
 
And also, I didn't learn much from that book, because I've already understood the exposure triangle via online tutorials.
 
If I understand correctly, though, using autofocus to try to cover two objects (one close, one far away) would leave one very lacking. For instance, when I tried to photograph my sons stuffed Geicko Gecko using a backdrop of the Space Needle in the distance. If I focus on the Space Needle, the gecko would be out of focus because mostof the dept of field would be behind the needle. If I focus on the gecko, the needle would be out because part of the DOF is lost in front of the gecko. Correct?
 
I'm currently reading Understanding Exposures (as recommended by many of you). So far I can't say I enjoy the author's writing. He seems very pompous, but then, that could just be me. Plus, while it felt like the beginning of the book was all about learning to shoot on manual, he VERY often states that he shot on aperture mode. AND despite his insistance on the "triangle," he seems to almost completly ignore ISO. I might not be to that section, though, I suppose. In any case, I've gleaned a few ideas to try, but there are at least a couple things I don't think he suitably explained (or I didn't understand them, or he will explain later).

First off, he keeps saying in reference to his photos that he pointed the camera to the sky (or some other portion of the photo), got the appropriate shutter speed for the aperture, then recomposed the picture. Maybe I should reread my manual, but I don't recall it saying specifically how to do this. Do I press the shutter halfway, hold it, frame the shot and go? If so, that doesn't seem too practical when using a tripod...

Second is the idea of how to focus with a large aperture (he uses f/22 a lot) such that everything is in sharp focus. He mentions setting the distance on the lens to 2 ft. or some such. However, on neither of my kit lenses do I see a designation of distance (nor, if I recall is there one on my 50mm f/1.8). First off, how does one determine which distance to focus with each lens (he gives only two examples with no explanation of how he came up with that), and second, without a distance option, how does one do this? I tried today while on my outing in Yakima Canyon (see my other post) and failed miserably.

Thanks for your help!

When he says point the camera to the sky, he means aim just to the side of the subject, so you have the same exposure minus the subject and set to the correct exposure. When he says recompose, you aim back in on the subject and frame them accordingly and snap the photo. (Read all of the descriptions for each photo also)

The book is very specific when he talks about using F/22 and distance to subject. (google focusing to infinity) Also, read the blue box on Page 11 and go to the website. Watch all the videos and go back to them when you get to that part of the book. He's not pompus, he's teaching. Get some thick skin quick, because photography is not polite.
 
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Or do you mean use the autofocus to focus aout 1/3 of the way between the two points?
 
Unfortunately I purchased the book from Amazon Kindle. Still need to figure out how to go to a specific page as it seems to set things up as "locations." I'll try to find the spot you're mentioning, though.

As for focusing to infinity. I've watched videos on that before, but it sure didn't seem like what was being referred to in the book...is that really what he meant?
 
Your example of using the gecko and the Space Needle will pretty tough one to fix with a single exposure and no photoshopping. The dof you are trying to cover is too much considering the distance from the camera to the gecko and the distance to the Space Needle from the gecko.
 
Ahhh...ok. After viewing the video that accompanies the book (thanks EIngerson) I get what he's saying. Now I'm just confused why so much time was spent on the subject in the book. It seems like some very useful advice, but unfortunately I don't have a lens that fits the bill. Good to know, though.

So in a case with a telephoto lens, setting the focus to infinity with a "large" aperture of f/22 or so would give the best chance at focusing two objects at disparate distances, though it may not be possible to fully focus both objects (as in the case of the space needle and gecko).
 
So with better lenses with a distance scale on them, I could set the distance to the hyperfocal distance and thereby have as much in focus as possible? Also, it appears from playing around with the calculator that the lower the focal length, the more likely I am to get everything in focus. So say with the gecko and space needle, I should have used my 18-55mm kit lens at the 18mm focal length. Am I understanding that right?
 
RxForB3 said:
So with better lenses with a distance scale on them, I could set the distance to the hyperfocal distance and thereby have as much in focus as possible? Also, it appears from playing around with the calculator that the lower the focal length, the more likely I am to get everything in focus. So say with the gecko and space needle, I should have used my 18-55mm kit lens at the 18mm focal length. Am I understanding that right?

No. Because to fill the frame, you'll have to go closer and you'll get less depth of field. And distance scale isn't useful most of the time, it doesn't work on far distances.
 
Certainly not arguing, so please correct wherever my misconception is. You say I'd have to get closer to fill the frame, but is that necessarily a bad thing? I realize that the closer you get the smaller the depth of field, but if I recall correctly from the dof calculator the hyperfocal distance for the 18mm on a canon would be about 2 feet. Shouldn't that be close enough to fill the frame appropriately even with a small subject such as the gecko?

Another thought/question. With the 100mm the hyperfocal distance is something like 30 feet at f/22. When using the lens for macro as opposed to say portraits, does the same focus distance apply? Hence the very shallow dof in macro?
 
You're observations are why I don't like UE. I don't think he's a good author. The best thing to learn from the book is how to get a good manual exposure, and that small apertures give you large depth of field, and large apertures give you a narrow depth of field. When DoF doesn't matter, choose a middle aperture to get the sharpest image. That pretty much sums up the book.

And I advise you to check out the charts at Canon EF-S 10-22mm f/3.5-4.5 USM Lens Image Quality for your lens. Compare the sharpness of the aperture at f/22 to f/16, to f/11, to f/8. Notice how massive a difference it (probably) is between f/22 and f/8. It's unlikely you'll need to use f/22 on a crop sensor.

As far as setting the lens focus distance to 2 feet, if for some reason you would actually need to do that, just focus on something 2 feet away. You don't need a scale to judge distance and it doesn't have to be perfect. Something that might help is to get a DoF calculator on your smart phone if you have one. That way, when you do need to balance between DoF and sharpness, you don't have to guess.
 

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