Help me with my night shots

digital paradise wrote in post #13247366
Mirror lockup won't do anything for the duration of the 30 seconds but at that first second when the mirror pops up you get vibration and the damage can be done right there. After the mirror pops up I always wait 5 to 7 seconds before opening the shutters.

Crafty wrote in post #13246986
BTW I think the issue you are coming across with manually focussing to infinity it actually finding infinity.
Taken from another post here, this is a page from a lens manual.. infinity can move around a bit:


So depending on temperature infinity could actually be anywhere between the vertical line and the laid down 8 symbol.

I think your aperture is maybe a little low, get it up around f8+

The other thing is how were you pressing the shutter ? you might of been introducing a little camera shake when pressing the shutter button. To rule this out either use a remote release or use the 2 second delay shoot mode, this should allow the shake to disappear before the shot is taken.

digital paradise wrote in post #13247271
Take the filter off for your night shots and keep it on for everything else if you are concerned about sand. If you want to use a filter you may want to spend a little more money. You get what you pay for.

tonylong wrote in post #13247300
So, a sturdy tripod. Mirror LockUp won't do much for a 30 sec. exposure. Two things that can help a lot are to turn off your lens IS (they tend to "drift" when on a tripod because it "winds down" and turns off). And then, using either a cable release, a wireless remote, or at least the self timer of the camera will cut down on camera shake from you pressing the shutter button.

You can get the shutter lock by holding down the shutter button half-way as you recompose the shot or, after getting a focus achieved by swiching the lens to MF so you can recompose and get the shot without re-activating the AF.

One thing you mentioned, about your aperture being f/5 and f/7 -- well, for now, I'd suggest you stick with f/11. That will ensure that a good "range" of your image will be acceptably sharp, what we call a "wide Depth Of Field" (DOF). That way, not just the buildings but also a lot toward the forground will be "apparenly in focus".

Now, there is nothing wrong with the MF approach, and nothing wrong with setting the lens at infinity, the question is will this benefit you? Some scenes, sure, if you can't actually use the AF! But, in these two scenes, the buildings have both light and good detail, which are the things our AF looks for! and, since it is important for you to have them properly in focus, then it makes sense for you to catch them with your AF!

The other approach to the AF is to use an outer focus point -- the one that is either on a subject or close to the subject. I use them all the time, you just have to learn to work with them.

Or, one other thing you can learn to do is to go to Live View and, in Manual Focus, zoom the Live View all the way in and centered on the subject you want to focus on, and take your time to adjust the focus, wait for jiggling to die down, repeat, and then take the shot. To do this effectively, I'd start with a quick attempt to get a "reasonable" focus, so the distant subject is not just a blur, or, in this case yeah, you could start at Infinity. You do realize that in normal conditions Infinity is not at the Symbol but at the inverted "L"...?