When I was using a point-and-shoot, I often ended up with blurry photos, so I got into the habit of taking two or three photos so that at least one will come out good.
A few months back, I upgraded from the point-and-shoot to the Sony NEX-5R. I was wondering if it's worth re-examining this habit, given that the NEX is a much better camera.
Some other changes I've adopted to eliminate blurry photos:
Using a Gorillapod or placing the camera on a flat surface, rather than trying to hand-hold it (or dial up the ISO and produce a noisy photo).
Using a timer for long exposures. I started with a 2-second timer, but I then read on photo.SE that that's not enough, so I sometimes use a 10s timer.
I also bought a traditional tripod in addition to the Gorillapod.
I bought a remote trigger to further eliminate camera shake.
Given that I've taken all these steps, is taking two or three photos of each scene excessive, when using the NEX? Or does it mean that I'm doing something wrong, and I can improve my technique?
I think taking multiple photos is still needed when I use my iPhone 5s, but please correct me if I'm wrong.
EDIT: To answer a few questions asked:
I'm talking about a scene that doesn't change, like a landscape.
Regarding the point that blur is not the only problem and that I could have an autofocus problem, taking multiple pictures isn't going to help, because I can't verify focus on the tiny camera or phone screen. I see that a photo is mis-focused only after I copy the photos to my computer, at which point it's too late. As Jeremiah helpfully points out, I will zoom in and check focus and only then take another photo.
Usually all of the photos are identical, but sometimes one is blurry. There aren't other significant differences, like focus, noise, framing / composition, etc.
Regarding TFoto's question about low-light, yes, this problem occurs more under low-light, but has rarely occurred under bright light. Perhaps taking multiple photos when it's bright is excessive.
Here are crops illustrating the problem. Here's a blurred photo:
and here's a clear one:
In this case, I used an iPhone, with the Cortex Camera app. This app takes a short video and then fuses them together to produce a better quality photo than the native camera app. While it handles some amount of shake, it can result in blur. This is one reason for blur. Other photos, taken using the built-in camera app on the iPhone, or using the NEX or a point-and-shoot, may suffer blur for different reasons.
This problem occurs less often with better cameras, like the NEX, as opposed to the iPhone 5s or a point-and-shoot.
I'm aware of blur caused by a slow shutter speed. I recognize that, and I believe I can deal adequately with it. That's not the problem I'm referring to in this question.