Does ISO effect Image sharpness?

[jake337]

Noise caused by high ISO ruins a photo.
Sharpness is meaningless to a ruined photo.

Subjective, but I'm still going to say not true. Grain can add to the image; I like it, a lot. I never turn my ISO below 400.

Agreed.

I think a bad composition ruins more photos than anything.

 

[cynicaster]

I can't remember where, but I read an article a few months ago where a guy who likes to shoot sports was saying that he sometimes shoots at higher-than-needed ISO because he feels a bit of noise enhances the "perceived" sharpness of an image. Admittedly I've never tried this, but sounds like ******** to me.

 

[Derrel]

More otherwise good photos have been ruined by slavishly sticking to ISO 100 than have been ruined by judiciously elevating the ISO to 320,or 400, or 500 when needed.

The idea that ISO 100 "always" leads to a better picture than a higher ISO setting is a common newbie way of thinking. The better d-slr cameras from Nikon today have sensors which yield superb results at up to ISO 1,000 or so, and then merely "excellent" up to ISO 3,200, and above that the performance is just "good".

One thing that REALLY builds noise is in-camera underexposure, which a lotta newbs often get.

 

[jowensphoto]

More otherwise good photos have been ruined by slavishly sticking to ISO 100 than have been ruined by judiciously elevating the ISO to 320,or 400, or 500 when needed.

The idea that ISO 100 "always" leads to a better picture than a higher ISO setting is a common newbie way of thinking. The better d-slr cameras from Nikon today have sensors which yield superb results at up to ISO 1,000 or so, and then merely "excellent" up to ISO 3,200, and above that the performance is just "good".

One thing that REALLY builds noise is in-camera underexposure, which a lotta newbs often get.

OK, that got me thinking... it's the same with every exposure element. There are rules (IE: always low ISO, always fastest possible shutter speed, newbs assume wide open aperture is best, WB should always be neutral, etc) but when broken effectively can enhance rather than detract.

Like motion blur or "silky" water shots, slow shutter speed can add to a photo just as higher ISO can. Changing WB to the "incorrect" setting can achieve a warm or cool feeling - when applied to the correct setting (like a sunset), can change the entire mood of a photo.

 

[AfternoonTea]

So really ISO does not directly effect sharpness (a sharp image is a sharp image), but increasing ISO in turns adds noise/grain (that may or may not be wanted) and filtering it may cause a image to soften?

I've taken notes in the past which I'll just post below for ISO new comers

ISO 100 - Daylight, strong sunny days, beach days, Snow on the ground, Lots of light, and bright light. In addition ISO 200 for more overcast

ISO 400 - General use, Cloudy days, indoors for window light portrait, Rainy days, Sports

ISO 800 - Evenings, sunsets, indoors without flash

ISO 1600+ - ​Low light situation, rock concerts, night clubs, your kids school play




60D lab results

60D users good ref for ISO noise tolerance
http://www.the-digital-picture.com/Reviews/Canon-EOS-60D-DSLR-Camera-Review.aspx

 

[Derrel]

Uh-oh...now you're thinking!!! lol

EXACTLY, jowens...how many times have we seen the post that basically reads as follows: "I just bought a 35mm f/1.8 and took a bunch of family pics and a lot of them are blurry,"? Have there been more of those posts, or more of the, "I just bought a 50mm f/1.8 and took a bunch of family pics and a lot of them are blurry!" posts? My vote goes to slightly more 50mm wide-open garbage threads.

I often say that a sharp but noisy photo is far better than a perfectly-exposed, low-noise SMEAR. In the many years I've been involved in photo forums, I've long been an advocate for shooting at an ISO level that is one or even two f/stops ABOVE base ISO...simply because it gives the photographer more choices, more leeway, more 'cushion'. I seldom if ever want to shoot wide-open...I often want to shoot at f/4.5 or f/4.8 or f/5.6. With flash, I often want to pick up MORE ambient light in the background, so I recommend to people to do as I do when shooting indoor bounce-flash: START at ISO 400, and notch up to 500 or 640 or even 800 ISO if it is at all needed.

For bounce flash situations, a lot of popular flashes simply do not have the power to get the kind of shots you WANT to get when the camera is laboring away under the artificial ISO 100 limit. For flash event work, using ISO 400 or 500, it means the flash will recycle and be ready for the next shot much sooner, battery sets last longer, and people are not BLASTED with full-capacitor discharge flash dumps...but instead, just brief little 'winks' of flash.