Another Experiment

My Dad was looking at some of my photos on Flickr and he commented in an email that I seemed to always have the ISO set at 200, and why did I do this as he used the 'auto' setting (I think - right, Dad?) and even with an ISO 3200, he didn't notice any appreciable 'noise'.  My response to him was that when I first started using the D90 with the kit lenses, I was having some serious 'noise' issues and I was much happier with the ISO at 200.  I also commented that I hadn't tried any different ISO settings since I got the new lenses, mostly because I have either been shooting in bright sunlight, or using an off-camera flash, and I hadn't been doing much low-light natural light photography, so ISO really has been a non-issue.  I finally added that I should probably try playing around with the ISO auto setting to see what I got.

So, I did.

All these photos were shot with the 24-85mm lens.

The first photo I took was of Abby snoozing on the stairs after our morning walk.  The camera bumped the ISO up to 1600, and at full resolution, the photo was a little grainy, but for viewing on the web (or probably even as a 5x7 or 8x10 photo) it is just fine.

 
I decided when I took the camera outside, I'd limit the upper ISO to 800, and since it was quite sunny, I stuck with the shutter priority setting, ranging from 1/3200 to 1/4000.   The sharpness of the auto ISO photos seems to be very good, but for reasons that are not clear to me, the camera was bumping the ISO around from 320 to 800.  Not surprisingly, the higher ISO photos were 'over-exposed'.  But with the magic of Lightroom, I was able to make the photos less bright.

Fr'instance....

Here's the non-tweaked photo, 1/4000, f/4.0, ISO 450

A little washed out.

 And then after a little tweaking in Lightroom

Still a little bright (that was my choice) but the sharpness was good.

Here's a non-tweaked shot with a fixed ISO.

1/4000, f/4.0, ISO 200

So, I think the lesson learned so far is that I should probably keep the ISO at 200 for very bright days (believe it or not, shooting in bright sunlight is not as easy as it sounds), but I should definitely play around with it more in lower light settings.

That said, here's a photo with the ISO set at 200, but I'm shooting into the shade - the auto ISO could have been handy here...

Here are a few more 'tweaked' photos using the auto ISO setting.

This one, other than being a little bright is a very sharp photo.

1/4000, f/4.0, ISO 720

A shot where the auto ISO worked out quite well.

Day 146/365.