manually focusing without a proper manual focusing screen, on a modern camera is close to impossible. I recently got myself a better focusing screen for my camera as it allows more accurate focusing. the problem with manually focusing a DSLR is that through the viewfinder you see an image as you would at f/5.6(and the
DOF that comes with it), but you probably set the
lens to f/2.8 or wider. The difference in where you think the plane of focus is, compared to where it actually is, is called pot luck. There is no way you will know where it is, as the
DOF you see(through the vf) is a lot deeper than the reality.
if you set the
lens to f/5.6, then what you see, is what you get.
Your ability and precision in achieving focus then determines whether you do so or not for that image.
The wider you set the
aperture, the less accurately you see the
DOF(and hence the point of focus).
Changing to a more accurate focusing screen is then fraught with a darker viewfinder image!.. so there is no free lunch here.
tips? I have none. you can focus bracket, which is what i used to do with my manual
lenses before I changed my focusing screen. Now I have to get the shot
in one as I changed the vf screen, and I need to get my mioney's worth(and the practise, to make perfect
).. but up until I made that change, and using my fastest manual
lens.. I used to take a burst of 3 shots. I used to get an image as close to focused as I thought was right, learned to either move myself(sway) back and forth and shoot three shots. I found through trial and error that I used to focus behind where I though was right(through the viewfinder image), so used to sway backwards to compensate. Funnily enough it generally worked.. but no guarantee! all of this is hit and miss.