Sony A850~Sony 70-400G~ISO 3200~1/1600 sec~F5.6~manual exposure~HH~overcast~12-28-2010~Houston,Texas~CS5 (ACR6)
Not my best image and I know the wing is clipped, but meant to illustrate how pushing exposure (camera histogram far right, minor clipping) can deal with digital noise. The RAW image looked washed out. Why overexposing is important is because anything exposed normally (correctly) at and above ISO 800 will show significant digital noise with both the Sony A700/A850 (and I assume many other cameras as well) and underexposure makes the image unusable.
In ACR the exposure was dropped, recovery slider used for minor clipping, and contrast increased. There was some digital noise, mainly fine grained as opposed to those nasty clumps, that was dealt with in ACR 6 NR with the luminosity slider. Sharpening (Smart sharpen in CS5) only used after downsampling to web presentation size. Probably could use background selection and NR in CS5.
comments and critique welcomed. regards~Bill
Last edited by WIlliam Maroldo; 12-29-2010 at 10:10 PM.
You did a great job of explaining that, William! There is a reason camera makers bother putting the higher ISO's on their cameras but you have to know when you can get away with using them.
If you do create an image like this and it does have more noise than you want to see, you can also take the image into Photoshop and duplicate the layer while changing it to screen mode. It will remove some of the noise and lighten the image quite a bit. Then use the opacity slider to lower the screen setting and stop just before the noise reappears. It doesn't work on very dark images but for lighter birds it can save the day as well.
GBH ISO3200
