Pictures taken at f8 vs. f22 landscape shots

weaponx525 · 08-24-2008, 09:06 PM

Hello all

I hope that this question isn't too obvious but I am still trying to get my head around the depth of field question. For example as the title of the post shows I have a question/request for photos taken at f8 vs. f22. Specifically I am looking for landscape shots so that I may appreciate the viewable differences in the depth of field. TIA.

*Canada_Rockies* · 08-24-2008, 09:30 PM

Originally Posted by weaponx525

Hello all

I hope that this question isn't too obvious but I am still trying to get my head around the depth of field question. For example as the title of the post shows I have a question/request for photos taken at f8 vs. f22. Specifically I am looking for landscape shots so that I may appreciate the viewable differences in the depth of field. TIA.

You can actually do better than looking at our shots, which will be greatly downsized when we upload them. To see the difference best, find a picket fence or something similar and shoot from a narrow angle. It would be best to use a tripod. You can then see the number of pickets in focus that increase as you stop down. Very graphic, and makes it easier to understand.

You would also need to do this at several focal lengths, as the focal length of the lens also affects the depth of field, as does distance from the camera.

I personally have learned to use the depth of field preview to visualize the effect. It does get a bit hard to see as the viewfinder stops down, but it can be learned.

Wheatfield · 08-24-2008, 10:05 PM

Originally Posted by weaponx525

Hello all

I hope that this question isn't too obvious but I am still trying to get my head around the depth of field question. For example as the title of the post shows I have a question/request for photos taken at f8 vs. f22. Specifically I am looking for landscape shots so that I may appreciate the viewable differences in the depth of field. TIA.

Poke around here:
Pentax Lens Gallery
It's a bit of a grab bag of images, but the stuff that Fred Wasti shot is really educational.

*Peter Zack* · 08-24-2008, 10:11 PM

I love CR's way of looking at DOF. Great easy advice. Any repeating pattern could be used to demonstrate the effect of stopping down or opening up the lens.

One item I will add. Unless the lens is a macro that can better handle very small apertures like f22, most lenses give the best optical performance between f8 and f11. Sharper and better resolution. At very small apertures you get diffraction of the light as it passes through the aperture (bending of light rays). It will actually make the image look a little soft.

*sewebster* · 08-24-2008, 10:18 PM

Quite a lot of landscapes, where nothing in the frame is "near" the camera, will have everything be in focus both at f/8 and f/22. The only likely difference will be that the f/22 shot is softer, due to diffraction, as described by Peter Zack.

It makes more of a difference if you have something close in the foreground and a far away background, but even then, for short focal lengths, f/8 is often enough.

I have "Understanding Exposure" by Peterson, and he seems to recommend f/22 and other small apertures for a lot of landscapes, but that probably isn't the best advice a lot of the time. Of course he does also point out he virtues of f/8 and f/11 etc. Sharpness isn't always everything either.

reeftool · 08-25-2008, 09:45 AM

The answers have been well covered so for my 2 cents worth....shoot a bunch of shots and bracket. You will see what works best with your particular camera/lens combo.

simonkit · 08-25-2008, 10:25 AM

Hi,

I can't imagine that you need F22, F16 at most & even this isn't probably often needed...to try & give you an idea here's a couple of useful links...

Hyperfocal Distance

http://www.dofmaster.com/doftable.html

weaponx525 · 08-25-2008, 09:34 PM

Hello all again

Thank you for all the patience and responses! The reason I chose f8 vs f22 is for the reason I get from reading "Understanding Exposure" by Peterson. In the first few chapters he mentions f values of 16 or greater, but I found that at those aperatures, the corresponding shutter speed is too slow and I either need a bright environment and/or a very steady hand (ie small aperatures equals long-ish shutter speeds).

I will definitely be trying more experimenting! I have been trying to use my 50mm f1.4 at small aperatures but maybe this is not the ideal focal length for "landscape" shooting.

*sewebster* · 08-26-2008, 12:04 AM

Peterson probably assumes you will use a tripod for any of these small aperture (large f number) shots. This would be a good idea of course, for pretty much anything, but often is not practical. There are certain situations where such a small aperture would be necessary, but maybe not as often as he might suggest.

*sewebster* · 08-26-2008, 12:15 AM

Sorry to post twice in a row, but here is perhaps more of an explanation of Peterson's thinking.

First of all, he's probably more interested in "getting the shot" than the absolute max sharpness. He is also quite possibly thinking of using film, not digital. So you can't just check the LCD to see if it is all in focus. If you set to f/22 then you can be pretty darn sure that everything will be in focus. If you have stuff in the foreground and background and set f/8 then yeah, lots of time it will all be in focus, but not always, depending on what you do, so you might go develop your film and find out you missed the shot. f/22 is "safer" in this sense, but you lose resolution.

*Nesster* · 08-26-2008, 04:02 AM

Just a wee side note here on the relative importance 'losing resolution' via use of f/22.

First, if you aren't using a tripod and a remote release you are losing far more resolution to shake. (I should know... I see it with my own photography. But still I won't always carry a pod)

Second, if you are using the usual zoom, you've already likely lost more resolution than stopping a really really good lens (prime or zoom) down.

With increased depth of field, more things are 'almost' in focus and the 'really' in focus bits are little less focused. In many cases with landscapes, this is not such a bad thing.

As mentioned already, a decision you make - consciously if you're lucky (I'm often not!) - is about the foreground. How much do you want it to be in focus? How much of it do you want to include in the frame? How close is it to the camera?

A lot of beach/water photographs tend to be with a wide angle lens, closed down to f/11 or below, and with filters too. (Or at least much of the instruction in Pop Photo explains it thus)

Here's an example, by an otherwise technically astute photographer... Anna Pagnacco... but apparently she realized the problem and has deleted the example!!! She has this landscape that has sufficient DOF, and then she had another where the foreground, especially a bunch of rubble, was badly OOF: very distracting. Oh well.

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