300 mm, ISO 1250, f/5.6, 1/400 sec.
300 mm, ISO 1250, f/9.0, 1/500 sec. … and cropped!
I acquired a new lens … a Panasonic Lumix G Vario 100-300 mm F/4.0-5.6 OIS Lens. I decided to get it after finding that most of my opportunities for taking pictures while out walking around the neighborhood required a long lens. With this lens on my Panasonic G3 I have an effective, in 35 mm terms, 600 mm lens. It will take me some time to master it since it is a challenge to balance the shutter, aperture, depth-of-field (DoF), ISO, and focusing when zoomed all the way out to 300 mm (effective 600 mm). You should note in the picture of the bird that I focused on the bird house and that an effective 600 mm focal length was still not enough and I still had to crop the image significantly.
I have learned in the short time I have had it that if I shoot in aperture mode that the camera will keep the shutter speed at 1/500 sec or faster. With that fast a speed in addition to the image stabilization system I have not experienced any major problems with motion blur caused by me while hand holding. If I shoot with ISO set to auto with a maximum ISO of 3200 I have found that I can generally shoot hand-held at an aperture of f/9 in bright light without the need to worry about settings. It is only in lower light that I start to have problems and have to open the aperture with concerns about DoF and noise from higher ISOs.
Focus is a different issue. The lens focuses quite fast and well on the G3 but it takes a lot of careful holding without a tripod to keep the small focus point where I want it. This is especially a problem in low light when the DoF is quite small. The lens will focus on objects as close as 5 ft., but at that distance the DoF is only about +/- 0.01 ft. and often at even greater distances and smaller apertures it is still only about +/- 4 or 5 ft.
Another adjustment that I find to be helpful is changing the way I carry the camera and lens. I find it easier to hold the lens-camera combination by the lens in my left hand. This enables me to bring it up to my eye quickly as well as rotating the lens to zoom quickly after I have grabbed the camera with my right hand and initially focused. In addition, while the lens has no creep now … it is stiff, I expect that it will eventually tend to creep and carrying it by the lens prevents that from happening.