Started with D40. Obviously there's no performance comparison between the two, so let me get down to functionality. Firstly, one of the things that drove me nuts about the D40 was having to navigate the menus to change key settings like meter, AF type, AF method. With the D300s these settings are now made with a switch on the camera body, which is exactly what I was looking for in my next camera. And that's the main difference between the D300 and simpler proposals. I didn't use the presets for portrait, landscape, etc. on the D40 and I didn't want them either. bam! Now they're gone. And here is the back. I've had the camera for a few months now and I'm still trying to figure out how best to use all the controls. Although I have many of them, there is a lot to learn. I've found that, as per the specs, noise shows up at ISO 800 or so, but you learn to live with it. There's now a lot of debate about when a replacement for it will arrive, such as the D400. Well, given the unfolding events, we don't know what the ramifications will be. I was surprised to see that the price started to increase after purchase. In any case, if you are looking for such a camera and are satisfied with the price, go for it. I don't think you will be disappointed. If shooting at a high ISO is important to you, this may not be the best choice. However, the need for high ISO is partly determined by lens choice. Camera-wise I like the D300s very much. It was everything I wanted and more.
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