jackpi Loc: Southwest Ohio

Noise is only one problem with high ISO. Dynamic range, tonal range, and color sensitivity also decline with increasing ISO. You lose 20% to 30% of those values going from ISO 100 to ISO 6400.

drklrd Loc: Cincinnati Ohio

You really need a tripod at any exposure under 1/30 sec. As we age that number seems to go up too. I have hand held at less than 1/15 but then I am an avid target shooter and the breath and trigger control of the sport aids in shooting cameras at low shutter speeds I always use a tripod unless I really need the shot and I do not have a tripod handy then a wall to lean on for support is sometimes handy.

bclaff Loc: Sherborn, MA (18mi SW of Boston)

First let's be clear, high ISO settings don't introduce noise.
Noise is more apparent when the Signal to Noise Ratio (SNR) goes down (signal is the light you collect).
So the less light you collect, the more apparent the noise.
You might collect less light because you raised the ISO setting but it's not the higher ISO setting per se that "introduced" noise.
In fact, paradoxically, higher ISO settings are quieter and have less noise in the deep shadows (at the expense of loosing highlights).
That's why astro-photographers shoot at higher ISO settings and care about something called Input-referred Read Noise.

For most photography the best Image Quality (IQ) strategy is to gather as much light as you can at the "native" ISO setting.
This gives the highest SNR and dynamic range. Often this is more than you need, but it is the best strategy.
If you cannot gather enough light at the native ISO then raise ISO as needed.
Plenty of caveats here since you might increase ISO to a point where unwanted in camera noise reduction is applied, etc.

This reasoning is behind the fact that many photographers (at least that I know) shoot in manual mode at native ISO with ISO Auto turned on.
Then you just make your photographic choices, aperture and shutter speed, and take whatever ISO you get (which will be the lowest for the situation).

WessoJPEG Loc: Cincinnati, Ohio

Highlights are brown, nobody hangs their crap on the wall.

ole sarg Loc: south florida

All of what is said below is so if and there is always an IF you do not want noise! For instance I like noise if sports shots of gritty moments such as a punch landing in a boxing match or in the mud in a football game. I like noise in many war footage shots as well.

So you can set the mood - as it were - with noise (grain) as you see fit.

moonhawk Loc: Land of Enchantment

Brown?

No I don't hang crap on the wall--Just my better stuff. All I was saying is your shot is a better example of why high ISO isn't all that great.

WessoJPEG Loc: Cincinnati, Ohio

I didn't say it was great, but I'm not afraid to go high ISO. I bet you have great stuff on the wall Di k Tracy.

CatMarley Loc: North Carolina

It is not just the noise that happens with high ISO. As the signal to noise ratio goes down, not only does the electrical trash become more visible, but in many cameras, the NR kicks in and the image becomes smeared, losing all the textural detail. In most modern cameras, however the problem is not apparent until over 1600. In film cameras, the grain had a completely different, more "organic" character and in some cases added interest to the photo.

CatMarley Loc: North Carolina

Yes, learning how to get accurate shots with a heavy long weapon with iron sights is great training for a photographer.

Djedi

Like everything else in this world, there are tradeoffs.
The big question is- where and how are you going to use this picture?
If it is for internet use and it won't be published above 1200X1600, and you are shooting an active scene in a dimly lit situation, you HAD BETTER use a higher ISO or you will get the results you did at ISO 200.
OTOH, if you expect to enlarge a scene to poster size, you had better keep the ISO on the lower side so noise is not apparent.

That said, I have taken aerial shots with my D800 at ISO 800 with a sharp Nikkor lens, which I enlarged to 30 x 40" which have little or no apparent noise after treatment in Lightroom, that have people thinking they were taken with a large format camera. So, for certain sensors, when you don't push ISO too far, you can still get fabulous results as long as you know the limitations of your equipment.

John_F Loc: Minneapolis, MN

I generally set aperture priority and let shutter speed and ISO go where the camera wants. I assume the camera firmware design engineers are also 'photo' savvy. I figure the multi-hundred bucks camera is worth it.

jeep_daddy Loc: Prescott AZ

The lower than ISO the less noise. Simple as that. But it's not practical to keep the ISO at 100-200 because there are time that you need a faster shutter.

photonutt1970

Well I've heard to use your ISO at any stop and I've also heard that ISO 800 is the new 200

Architect1776 Loc: In my mind

ISO is another tool option. I shot a daughter's college graduation with a 100-400 and to freeze action in a dim building used a high ISO. Did a bit of PP to reduce noise and it made shots a bit soft but still acceptable as eyelashes were still discernable. This was far better than blurry shots due to a slow shutter speed. So just use ISO as conditions dictate and your vision of what you want.

oldtigger Loc: Roanoke Virginia-USA

Sensors have improved and there is more usable range than a few years ago.
As wessojpg pointed out with his ISO 16000, the sun won't stop going around the earth just because you choose a high ISO.
Get familiar with your gear and determine how much noise you find acceptable.
I think the ISO 1000 is is pushing it but others who do PP may consider ISO 5000 ok.
Once you have that in hand, start looking at what portion of your image is being most effected by the noise.
Learn to work around or avoid problem lighting

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