I love taking close up photos of flowers and to a lesser extent, insects. Since my 18-135 Nikkor wasn't helping me too much in this regard, I bought a new Tamron 90mm Macro for my Nikon D40. Unfortunately, this lens doesn't autofocus with my camera and I am having big trouble judging the focus manually. I invariably get it slightly out of focus and end up getting fuzzy shots.
I am now using the method of taking three or four or more photos of the same subject and keeping the best out of them, but almost impossible to do when shooting insects.
For example, take a look at this one of an ant:
Is there anything I am doing wrong? I checked the diopter adjustment and it seems OK. I have also seen posts here and elsewhere stating that a tripod is nearly useless when photographing insects and I don't use one myself. I guess I will get the hang of it as I use the lens more, but if there is anything obvious that I am missing, please advise me.
My second question is about how to get more of the view in focus. Using f/stops of 12 or higher doesn't seem to work, especially in natural light. I have seen most macro photos of flowers have almost all the flower in sharp focus, whereas most of mine tend to turn out like this:
OK, this flower was only 5 to 7 mm across but I would still like to have more of it in focus than is seen in the photo above. Any suggestions would be welcome.