F22 or F8

[Bob Stevenson]

What you have said is basically true but how important it is in practice is a quite different set of considerations.  The best way for you to go on this is to do your own tests and see how different apertures actually look when you view your own work,..shoot a scene at infinity with NO foreground, (so you don't confuse lack of depth of field with lack of resolution/quality) preferably with tripod, take careful notes.

[pmkierst]

Here is the question you have to ask yourself: If all of your subject is not in focus (i.e. insufficient DoF), does it matter how good of quality the lens is? You're going to toss the picture anyway.

[francois]

JF,
An interesting article on this site could give you some pointers.


francois

[b.e.wilson]

Depends on the focal length of the lens. Short lenses (wide angles) have very deep DOF's, so f/8 is plenty to ge tth escene sharp. But longer lenses have narrower DOF's, and stopping down is essential if I want the entire scene in focus.

And occasionally you want to pick one thing out of the landscape, so open up the long lens all the way and focus on that one thing and let the rest go fuzzy.

[clwpaddler]

Interesting posts by all.  I may have missed something but is it not what is in the mind of the photographer thats is important.  If you want the foreground soft to accent the distance or lose the background to force the eye of the viewer to see the foreground, then so be it.  Rules are to be broken and some of the best photographs ever taken blatently break the rules.  I also found somewhere in this post the reference to the lens having greater or lesser D.O.F..  This may be confusing since no lens has built in DOF but due to design and optics creates it only.

[Paradis]

I have a big dilema,
I love to shoot Landscapes (of course its for that I'm here), in the wonderful rewiews on this site I allways noticed that Lens have theres best potential at 2 stop from the full aperture (ex/: F5.6 for my 28-70 F/1:2.8), not really a choice for a deep Landscape, I just want to now what is your personal choice, if for exemple some people use F16 or F22 for a great DOF but a less image quality ?

JF

[Dale_Cotton]

I agree with Bob on the importance of testing but I'm going to diverge a bit from there. First do Bob's tests, which are critical, then consider the following as building on that:

Most (but not all the time) in doing landscapes one wants max DOF - as much as possible of the scene in focus. If I have content in the foreground, midground, and background, I usually want all of it to be in sharp focus. If I have to make a sacrifice, I will usually accept a bit of de-focus to the background, since this seems natural to the eye, but not to the foreground.

Simplistically, I could simply use the min aperture setting on my lens and work from there. But the problem is the trade-off between DOF blur and diffraction blur. The larger the aperture the greater the DOF blur and the smaller the diffraction blur and vice versa. There is a cross-over point at which using a smaller aperture gains you nothing, because diffraction blur overrides the improvement in DOF. This will vary by focal length, because the actual size of the aperture at a given f/stop varies according to focal length, and quite possibly from lens to lens. I work with the same 35-70 zoom most of the time and found that f/11 gives me the most sharpness from foreground to background; i.e. represents the best compromise between DOF and diffraction.

Everyone needs to do his/her own tests on this over all the different focal lengths and lenses he/she employs. My own tests were to set up my camera on a tripod in front of a static scene with objects at every distance from a few feet to the horizon then take shots at all focal length and aperture combinations. Be sure to read Michael's article on MLU and cable releases first. Such a test will be a great time to practice minimizing all vibrations.

[K]

Bring a DOF calculator or formula whatever. Calc and frame your shot to accomodate f/8. Adjust a bit based on that. If you have to include close foreground that throws your f/8 or neighboring aperture away, then you just have to sacrifice the sweetspot.

[Paradis]

I found a lot of useful and interesting features in every of your answers, I love this forum, its a lot more serious than others !
Thanks to everyone for your help, I really apreciate it !

JF

[robertwatcher]

I very seldom use the standard (boring focal lengths of 28 to 75mm) - and prefer the more extreme focal lengths. I'm not too interested in how the specs look - more if I'm getting the quality image I'm after.

The two lengths I prefer are 20mm for wide angle and 180mm to 300mm for long focal lengths - especially for landscape, architectural and editorial work. My view is that I am using my wide angle for the effect of everything in focus - so close it right down to f22 (technically f16 would be better but a difference isn't noticable in my work). On the other end, the reason I'm using a long lens is to have the compression effect and shallow depth of field - plus I need all the shutter speed I can get to have sharp shots - so I almost always shoot wide open, even with lenses that aren't optimized for it like my 75-210mm and 75 to 300mm zooms  or my 300mm f4.5.

The only other focal length I use for candids and portraits is my 85mm 1.8 and I regularly shoot it wide open with fast film for natural light indoor shots and only close it down to f5.6 if I have a portrait of more than one person where DOF is more of an issue.

Experiment like mentioned above - you may well be satisfied with the results of closed right down for wide angle and open right up for teles - as I generally am.

http://watcherreport.com/prophotoforum/

[Paradis]

Thanks a lot, Bruce and Rob !
Very interesting answers and advices about Lens choice, its always nice to know what others likes to use in differents situations !

JF