Docsamson wrote:.

What I like to ask is how big a deal if the noise levels aren't thegreatest at ISO 400 and above? 400 should still be nice looking butwith some noticeable grain. But outside of low light levels and othercertain and special conditions, is ISO 800-3200 used very often?.

For low light use without flash - yes!High ISO abilities open up a new world for photos..

I've read somewhere that noise reduction that some cameras employ canbe overly aggressive and I'm more concerned about that..

It's a personal preference thing as each manufacturer makes choices as to how much noise reduction to use at a given ISO..

I can't quite wrap my brain.

Around changing the ISO settings with each shot..

There seldom a need to do that as most cameras do it automatically.However, some cameras provide useful manual control over ISO settings..

With film, you usually set the ISO on the camera whenever you loadedthe film. You never changed the setting unless for a very specialreason. Now you can change the f/stop, shutter speed AND the ISO withevery shot if you wish?.

On a DSLR, yes. On P&S cameras some combination of those can be changed, but not usually all of them..

Before, noise levels seemed to be more a film factor rather than thecameras. Is there any substitute for experimenting with differenttypes of film-like properties like noise or color saturation in thedigital age outside of just buying different P&S's?.

Now with "post processing" much of the experimenting can be done later..

Digital has changed almost everything but the eye of the photographer!..

Docsamson wrote:.

With film, you usually set the ISO on the camera whenever you loadedthe film. You never changed the setting unless for a very specialreason. Now you can change the f/stop, shutter speed AND the ISO withevery shot if you wish?.

Yes. Digital cameras divide film's "light gathering" and "storage" chores among a (usually) permanent sensor and a (usually) removable memory card..

The sensor only has one true ISO sensitivity, but the camera can simulate other, higher ones by amplifying the signal. You can raise or lower the ISO from photo to photo and there is no need for "push" or "pull" processing, no "OMG half the roll needs to be developed one way, half another.".

But if you raise the ISO high enough, the shots that use it will have more noise. This is less of a problem on DSLRs than on digital point-and-shoots (due to larger sensors and larger photosites), but it is still there. So you want to keep ISO set low as long as you've got enough light for your f/stop and shutter speed goals...

P&S cameras with larger sensors will usually have better high ISO performance. Even then, it is a matter of taste between lots of internal processing and a noiser but more detailed image. I have found that if you can adjust the color and contrast to a truly neutral amount, one can pick up another stop..

I started out with an SLR, went to a P&S megazoom digicam and then went to a DSLR. The DSLR did the trick for me. I can shoot a clean ISO 1600. ISO 3200 will do in a pinch...

Docsamson wrote:.

What I like to ask is how big a deal if the noise levels aren't thegreatest at ISO 400 and above? 400 should still be nice looking butwith some noticeable grain..

For many P&S type cameras, even ISO 400 can be very noisy..

But outside of low light levels and othercertain and special conditions, is ISO 800-3200 used very often?.

Not if the camera is noisy at high ISOs. But otherwise, yes. It can mean the difference between flash and no flash. It can mean hand-holdable shutter speeds or having to use a tripod. Higher usable sensitivity can also allow blur free action shots..

I've read somewhere that noise reduction that some cameras employ canbe overly aggressive and I'm more concerned about that..

Certainly some camera try to emulate decent high ISO by aggressive noise reduction..

Forgive me for asking what seems to be a silly question. I haven'ttaken photos since the film days and I can't quite wrap my brainaround changing the ISO settings with each shot..

With film, you usually set the ISO on the camera whenever you loadedthe film. You never changed the setting unless for a very specialreason. Now you can change the f/stop, shutter speed AND the ISO withevery shot if you wish?.

Yes, that is correct, although in practice one would tend to only change the ISO when the lighting changes: For example, when moving from bright sunlight to indoors..

Also many newer models have some sort of auto-ISO mode. The Fuji F31fd that I have, allows you to set a maximum ISO (say 800) and it will vary the sensitivity up to ISO while retaining the other parameters you set (such as shutter speed and aperture)..

Before, noise levels seemed to be more a film factor rather than thecameras. Is there any substitute for experimenting with differenttypes of film-like properties like noise or color saturation in thedigital age outside of just buying different P&S's?.

Read the reviews, especially the extensive ones here at DPReview that compare ISO setting s of different cameras..

Brian A...

Noise from smaller sensors is worse than from larger ones..

Given two small sensors of roughly the same size the one with the lower pixel count will often by less noisy ( "trying too hard" is the expression I'd use )..

DSLR sensors are huge by comparison with compacts and bridge cameras. Hence they produce less noise and gather light more accurately..

DSLR sensors are about 1.5 times smaller than the standard 35mm frame, and you will see this number a lot in relation to lenses..

Digital noise does not look like film grain and can look like mottled coloured areas. It is most obvious in any more-or-less flat colour area. I find it most distracting in off-white areas myself..

Note that digital cameras that generate JPEGs will attempt to reduce the appearance of noise in the JPEG. Digital cameras that let you shoot RAW do not do that to the RAW image, which is basically the unprocessed sensor data. RAW gives you more control over how the image is processed, whereas JPEG ( from the camera ) lets the camera do that..

Because cameras generating JPEGs do the noise reduction for you you are reliant on the quality of the camera's noise reduction. Noise reduction can actually lower the detail, so many people ( like me ) prefer to shoot RAW and do noise reduction using software after post processing the image..

Noise is most apparent in darker areas and will be made much worse if you do not expose correctly. Look up the term "expose to the right" - the Luminous Landscape website has a good description of this. That website might be a good place for a person moving from Film to Digital to start from..

StephenG.

Pentax K100DFuji S5200Fuji E900PCLinuxOS..