Hi Christine,
I've had a look at all the photos and it seems as if both squirrel photos were taken at the same camera settings.... despite one being slightly blurred. The blurred shot could be due to some camera shake or that the auto-focus just didn't lock onto the subject.... that does happen every now and again.
Yes, you do want the 'A' in the bottom left-hand corner (denoting aperture priority). You get this by pressing the mode button (on top of the camera) and rotating the dial until you see the 'A'... it will cycle through various modes, but 'A' is what you want.
Not too sure what you mean by "someone else had a fiddle,and knocked off the tele zoom(I think, put something on a no 3 setting" .... they may have gone through the menus and adjusted the camera to tell it that the Nikon 3x teleconverter was attached. This wouldn't have made much difference, but it's best to have the camera think it doesn't have any additional lens attached (set on 'normal'). This is on
They may have moved the rotary dial.... and when in 'A' mode this will change the F number, possibly to a higher number and then the shutter-speeds will be lower than if the camera is set to the lowest F number. The F number should always be set on the lowest F number available (turn the dial clockwise to lower this number, anti-clockwise to raise it).... though the minimum F number is related to the camera's zoom position, so when you zoom right in to maximum, the lowest F number available will be f5.1 and at minimum zoom the lowest will be f2.6.
You have to remember that the camera looks at the scene and determines how much light is available.... so not every shot will have the same shutter-speed. Move your camera around and you'll see the shutter-speed change depending on the darkness of the scene. Obviously, when you zoom in with the camera, the shutter-speed will go down because there is less light coming in from the scope. You can get away with slow shutter-speeds if the subject is very still but any movement from the subject (or by your camera/scope/tripod) will result in blurred images.
One of your water lily shots (yellow one?) would always be difficult for the camera to get a good focus on.... the best shots will always be where the camera has a specific object large in it's view, hopefully against a contrasting background.
Pity the Squirrel had it's head down.... but you can give a gentle cough to get it to look up for a nice shot (works with some birds, but make sure you're alone, otherwise you could end up with your scope inserted where the sun don't shine
I'm not a fan of the Nikon remote, my experiences with it are totally negative.... it's often slow and unpredictable as well as the plug into the camera becoming lose so you'll get no operation at all. However, some love it (there's a chap in Hampshire and I think another in the states
The shutter button (and remote) is a two stage affair... a half-press will get the camera to lock onto the subject, then press further to take the shot instantly without having the camera to search for a focus lock (which takes time), though this is not relevant if you use the 'Infinity' focus setting (mountain symbol) as this effectively shuts down the camera auto focus. Infinity focus mode is best at longer distances where the camera would struggle to find a focus lock for various reasons.... If the subject is big in the scene, macro produces the sharpest results.
Hope this helps.
And read that manual!
Regards,
Andy