I took the G7 as my only camera to the Christmas Eve service last night. In the past, I've used both my 20D and a Sony Videocamera for the job, but this time, I figured I'd just depend on the G7.
Before I go further, let me explain the conditions -- the church is very, very dark. For instance, 1/6s at F/4 and ISO 400 is about as good as it gets. It really is a situation that exposes the limitations of a camera. Add to that the necessity of reducing noise, and it is really hard to get a camera to work well if flash is not allowed...
My experience with the G7 was mixed. There were a number of good things:
- The G7 is super quiet -- I could shoot away without worrying about the click-Ka-CHUNK of the 20D bothering people.
- The zoom on the G7 along with IS makes a very usable combination, even at very slow shutter speeds. By doing a minimum of bracing my arms in a sitting position, I was able to get a decent number of keepers around 1/10th or 1/20th.
- The G7 was quite good at acquiring focus quickly. I was pleasantly surprised.
- The built-in video mode was very handy and easy to use, once I figured it out. The key is to set zoom, acquire focus, then depress the button fully to record.
- The optical viewfinder is pathetic, but that is made up for with a very good implementation of live-view. I never missed the optical viewfinder (accept for the cases where I wanted to steady the camera well).
- Let's face it -- the G7 has a relative large chip for a point and shoot, but it still has pretty abysmal noise performance compared to a dSLR. Below is a 100% crop from the shot above -- I believe this is ISO400.
- You can't shoot at high ISOs in RAW... I know I am repeating myself, but my 20D is at least serviceable at ISO 1600 and quite good at ISO 800 for web-size images. The G7 just craps out past ISO 200 and even shooting with RAW you can't save it. (Disclosure -- I haven't tried RAW on the G7 since it isn't natively supported, but the reviews for it haven't compelled me to install the hack to make it work)
- You can't zoom during videos (well, you can, but it is only digital zoom). That is probably because the zoom would be super noisy...
- You can't autofocus during videos -- this is a big issue.
- The autofocus light is a light green, VERY directional light that can be quite distracting if you shine it towards, say, your kid, while he's trying to say a line. If it was possible, I'd love an infrared autofocus light (not sure it is possible with this technology).
Overall, I know there's some things I can tweak in my technique, but I know the G7 is not going to be a good low-light camera for anything but snapshots. I've heard that the G11 is the first in the G-series that has improved high-ISO performance -- in fact, the G11 at ISO 800 looks better than my G7 at ISO 200! -- and I might look into getting one used sometime down the road. The G7 will remain for me a beater-camera for snapshots that has some advanced features too.