First off, I have such a problem posting to this forum as my paragraph breaks never show-- people have tried offering suggestions in the past which I have followed to no avail. So frustrating. My apologies for the lack of paragraphs!I have been using my Nikon D5100 for a few years now and have never had it serviced. I mostly take food photos and found that the kit lens wasn't working for low light restaurant conditions. After some research and asking around, the AF-S Nikkor 50mm f/1.8G lens was recommended. The salesperson said he uses this himself in low light conditions like bars to take his photos and he loves it, etc etc 
To begin with it worked GREAT. I use A mode but sometimes if in a hurry (like not wanting to hold up people eating their food, I'm a hobbyist food blogger), I would sometimes go to no-flash Auto. I use Auto ISO. My photos were turning out well and I was very happy with them. I was also taking great pics of my cats at home in the evening, when light is low . In the past month or so however, everything seems to have gone wrong. All my shots are blurred, no matter how I try to focus or no matter the settings. I'm not doing anything different to what I did in the past with this lens when getting good pics in dimly lit venues Last week I was taking photos in a restaurant that was still low light but lighter than most I've done before, and every shot was blurred, or the shutter would click-clack slowly. I'm not putting it down to shaky hands, I had the camera resting on things at some points Basically I am doing nothing different to when I was taking shots I was happy with when I bought the lens. Also one evening in a restaurant with low-ish light (but still a good amount for this lens), I was noticing a sort of brief glare kind of flash when looking through the viewfinder. At the time I thought "this is weird, but has it always been like that and I'm only noticing now"? I did a brief google search and found quite a few references to people saying this lens was great to begin with but then stopped working My kit lens works fine. This 50mm lens works fine for food photos (so I'm kinda close up to the subject) during the day. It's only recently in the low light conditions that it seems to be misbehaving. It's exactly like the kit lens (which doesn't go down to f/1.8 and would constantly give me the "subject is too dark" messages), which of course wasn't suitable for the low light conditions, which is why I went out and bought this particular lens. :? Any ideas what's going on? I will be taking the camera in to a store next week, but ah, please feel free to educate me on getting cameras serviced, how often that should happen etc. Do lenses need to be taken in for a camera checkup as well? Thanks!
To begin with it worked GREAT. I use A mode but sometimes if in a hurry (like not wanting to hold up people eating their food, I'm a hobbyist food blogger), I would sometimes go to no-flash Auto. I use Auto ISO. My photos were turning out well and I was very happy with them. I was also taking great pics of my cats at home in the evening, when light is low . In the past month or so however, everything seems to have gone wrong. All my shots are blurred, no matter how I try to focus or no matter the settings. I'm not doing anything different to what I did in the past with this lens when getting good pics in dimly lit venues Last week I was taking photos in a restaurant that was still low light but lighter than most I've done before, and every shot was blurred, or the shutter would click-clack slowly. I'm not putting it down to shaky hands, I had the camera resting on things at some points Basically I am doing nothing different to when I was taking shots I was happy with when I bought the lens. Also one evening in a restaurant with low-ish light (but still a good amount for this lens), I was noticing a sort of brief glare kind of flash when looking through the viewfinder. At the time I thought "this is weird, but has it always been like that and I'm only noticing now"? I did a brief google search and found quite a few references to people saying this lens was great to begin with but then stopped working My kit lens works fine. This 50mm lens works fine for food photos (so I'm kinda close up to the subject) during the day. It's only recently in the low light conditions that it seems to be misbehaving. It's exactly like the kit lens (which doesn't go down to f/1.8 and would constantly give me the "subject is too dark" messages), which of course wasn't suitable for the low light conditions, which is why I went out and bought this particular lens. :? Any ideas what's going on? I will be taking the camera in to a store next week, but ah, please feel free to educate me on getting cameras serviced, how often that should happen etc. Do lenses need to be taken in for a camera checkup as well? Thanks!