ISO for Landscape

I have been shooting some landscape lately. I always use ISO100. Someone told me the other day that i should be using ISO200. He said that it gives more depth to the photo. I dont understand that. I thouhg the depth was based on the lens and f stop. plus i always thought that you always use the lowest ISO possible to produce an image with less grain. Can anyone shed some light on this?

You're right, he's wrong.

I have never heard that. My current photography is a full time agriculture photographer, and makes a great living at it. He shoots landscapes for bucks. He told me that his camera never leaves 200, though, as a matter of convenience.

The only thing I can think of is, since 200 is twice as light sensitive as 100, you can go with some smaller apertures for deeper DOF.

There is no One Right Way to do anything in photography. Everything has a trade-off.

Keeping the ISO low will keep the noise down, but it means having to use a wider aperture and/or slower shutter speed than you could with a higher ISO. The wider aperture will reduce depth of field, and the slower shutter can pick up camera shake or motion blur from stuff blowing in the breeze. This is more of a problem if you're using a polarizer (due to the loss of light).

By the way, on certain Canon DSLRs—the 20D and XT/350D at least—if you're shooting Raw you'll have slightly less highlight headroom at ISO 100 than at higher ISOs. Maybe 1/3 stop or so. Probably not enough to worry about for landscape photography.

There really isn't much difference in noise level between ISO 100 and ISO 200 in modern Canon DSLRs, so if there's any advantage to using ISO 200 in a particular instance, it might be worth doing.

Might I suggest that you try it both ways and see what you think?

Jeff Wignall has a new book "exposusre." Get it & read it... You will not regret it....

dougbutch wrote in post #5467928
Jeff Wignall has a new book "exposusre." Get it & read it... You will not regret it....

Is that how he spells it?

Maybe he uses Tv mode so he ends up with more more depth of field with realizing what he's doing.

You almost always want to use the lowest ISO possible for landscape unless you are going for a grainy effect. When you want to increase your shutter speed w/o adjusting aperture is the other scenario in which you would bump up the ISO. For example if there is wind blowing flowers, grass, trees, ect and you want to freeze thier motion or if you are shooting a waterfall in dark conditions and don't want such a long shutter speed you would bump up the ISO if assuming using a smaller aperture was out of the question. It's a give and take when choosing your aperture, shutter speed, and ISO; prioritized the adjustments.

Well if you use a higher ISO, you're more capable of using smaller apertures, therefore enabling you to gain more "depth" in your photo (if no tripod is handy). So, technically he isn't wrong but the ISO, itself, doesn't give you more depth. But, when shooting outdoors during the day, usually ISO 100 is suffice for the lowest of apertures depending on the time of day. So, lets just say he is more correct when the sun starts going down. But, from the way your story was explained it seems as if he doesn't know what he is talking about.

I heard this a while back, and since then I have gone to 200 ISO just so I can use faster shutter speeds. NOTE: In this situations, I am already using a fast shutter speed but I may use 200 ISO just so I can get even a faster shutter speed, and get rid of all possible camera shake, even if I am already shooting at 1/200+

Why don't/didn't you ask him to shed light on it?

Sure, youd have a fast shutter, but the shutter and ISO don't directly correspond to your depth of field at a given aperture. They will only affect exposure.

Ok my first reaction was he's talking out his arse but a couple of people on this thread have said they've heard this too. I must say I'm confused then, how can going to ISO 200 make a difference.

It was my understanding that to get a higher sensitivity ISO the receptors on the cmos chip were electrically doubled in strength (can't remember how to word this bit correnctly). So presuming that each receptor is equally doubled there shouldn't be any difference in dynamic range?

It's interesting, i've always used 100 on landscape shots when using a tripod.

I suspect that what he's referring to is a greater depth of field; at a higher ISO you can use a smaller aperture for more DoF and still keep a reasonable shutter speed. (Tripod or not, if there's any breeze you'll get possibly unwanted blurring of vegetation, clouds, and the like at slower speeds.) There's not a whole lot more noise, especially at normal print sizes, at ISO 200 vs 100 these days.

Was this "somebody" Ken Rockwell???