iso help

[coltonw911]

i like shooting my portraits with a 250 iso but is there a better one for portraits, what should i be using/whats the differece?

 

[fmw]

Always use the lowest possible ISO setting. Go out of your way to use it. Use tripods. Anything. Keep the ISO as low as possible. As soon as you increase it beyond the minimum you introduce noise.

 

[Big Mike]

The only time you should increase your ISO above the minimum...is if you need it to get a faster shutter speed or smaller aperture for more DOF.

 

[Garbz]

It depends on the camera. I find my D200 most acceptable at ISO200. Above that though quality starts to be compromised.

 

[EOS_JD]

The only time you should increase your ISO above the minimum...is if you need it to get a faster shutter speed.

i would have ended the sentence there Mike. If you want a smaller aperture then do that at the minimum ISO unless you slow your shutter speed down to require a higher ISO.

 

[ksmattfish]

Lower isn't always better. ISO 50 or "L" on Canon DSLRs is really ISO 100 overexposed a stop, and then in-camera software tweaked. In some cases this can cause more noise than ISO 100. Also with Canon DSLRs, all of ISO settings besides 100, 200, 400, 800, and 1600 are in-camera software tweaks, and appear to have more noise than if you stick to the standard ISO scale.

 

[EOS_JD]

Lower isn't always better. ISO 50 or "L" on Canon DSLRs is really ISO 100 overexposed a stop, and then in-camera software tweaked. In some cases this can cause more noise than ISO 100.

It can't be overexposed if you also halve the shutter speed (which you would need to do) but you are correct that it's software driven in-camera and should not really provide any great advantage over ISO100. It should not (if done corectly add in any more noise though).

Also with Canon DSLRs, all of ISO settings besides 100, 200, 400, 800, and 1600 are in-camera software tweaks, and appear to have more noise than if you stick to the standard ISO scale.

I'm not sure that any of the other ISO increases are "software tweaks!" You are increasing the gain therefore making the sensor more sensitive to light. This increase in gain will add digital noise to your image.

Also this is not just true of Canon dSLRs but of ANY digital camera (dSLR or compact)

 

[Mike_E]

Use a low ISO unless you have to have more flashes per unit time from a battery operated flashgun. Or you are about to run down your last set. The higher the ISO the lower the power the flashgun has to use to accommodate the camera-hence faster recharges and longer battery life.

mike

 

[Augphoto]

Use a low ISO unless you have to have more flashes per unit time from a battery operated flashgun. Or you are about to run down your last set. The higher the ISO the lower the power the flashgun has to use to accommodate the camera-hence faster recharges and longer battery life.

mike

Good point Mike. I've always used to lowest setting possible but, when using flash I may have to revamp my technique now.:hail: