WhimperingCat:
Let me offer a couple alternatives. A trick that landscape photographers often use is to set aperture to a reasonably high number for good depth-of-field (I rarely go above f/11 to avoid lens diffraction, but you can push some APS-C lenses as high as f/22 for even greater depth-of-field albeit a slightly fuzzier look for distant objects). Focus your lens approximately 1/3 into the frame - whatever area you want to have in sharp focus. Once focus is set, switch to manual focus mode to prevent the lens from refocusing. Compose and shoot. This method usually works (and no lens markings are needed), but I prefer using a second method offered by George Lepp, a widely know landscape photographer:
Select the closest foreground object you want in focus and then set the lens focus to twice that distance. For example, let's say there's a good-looking foreground rock you want in focus that's 3 feet away. Set aperture to f/11 or higher and focus on any object that's 6 feet away. Switch to manual mode so the lens doesn't refocus. Compose and shoot. For lenses without distance markings, you'll need to guess/approximate the 6 feet. Maybe aim at some tree or have a friend stand 6 feet away. Set your focus.
The reasoning behind this method is that the hyperfocal focus point provides 1/2 the distance in front of it as being in focus. So, if your lens is adequately stopped down and focused at 6 feet, everything from 3 feet to infinity will (theoretically) be in focus.
You may not have lens markings that let you use one of the dozens of depth-of-field calculators and charts available on the internet (I spent literally DAYS going through them all to find one that worked for me and my circle of confusion) but I found George Lepp's method worked just as well for my K-7 + Sigma 17-70. Using simple numbers like 2,3, and 4 feet for close objects matched up well with the calculators/charts. And I have several Columbia River Gorge waterfall pictures to prove it, LOL.
While you won't be able to provide your teacher the exact assignment they asked for, do some name-dropping (George Lepp) and how much you now know about landscape techniques. Maybe you can still impress them. (Or baffle them
).
Regards,
Uncle Lew