Focus please?

[iann]

Not quite the effect I was looking for:

polycephalus-0721a.jpg (39.7 KiB) Viewed 1534 times

The great thing about digital cameras is you find out immediately and try again. Echinocactus polycephalus is looking a little wrinkled after braving the heatwave without water. Maybe it can have a drink when the thunderstorms arrive this week.

polycephalus-0721b.jpg (84.74 KiB) Viewed 1534 times

[Peterthecactusguy]

hahahaha I have that issue with my camera sometimes too, it focuses on the wrong thing. Oh well it looks thirsty, we finally got rain today

[DaveW]

That's why they don't recommend autofocus close up Peter since depth of field is too small to cover autofocus inaccuracies. Best to learn to use manual focus and screen focus.

http://www.digitalcameraworld.com/2012/ ... rp-images/" onclick="window.open(this.href);return false;

As Ian says though you do have instant feedback with digital, unlike the old film days when you had to wait until the film was developed to find you got it wrong!

[iann]

That's why they don't recommend autofocus close up Peter since depth of field is too small to cover autofocus inaccuracies. Best to learn to use manual focus and screen focus.

http://www.digitalcameraworld.com/2012/ ... rp-images/" onclick="window.open(this.href);return false;

As Ian says though you do have instant feedback with digital, unlike the old film days when you had to wait until the film was developed to find you got it wrong!

I rarely get the case of the camera focussing too close, since I'm usually near the closest auto-focus point anyway. Usually it is a problem with small objects like Haworthia flowers, when it decides to ignore the insignificant speck and focus on the fat cactus behind it

[DaveW]

"I rarely get the case of the camera focussing too close."

You did in your fist picture though Ian, but in the second one that nearest spine is now out of focus, however you were probably restricted by what depth of field you have available as to what you could get in focus. Generally speaking the eye notices out of focus objects nearer to it more than those behind the point focused on.

The problem with close up's using autofocus is the ideal focus point may be between two objects where there is nothing for autofocus to focus on. Using screen focusing you can often spread depth of field over the two, whereas autofocus would either focus on the front one putting the far one out of focus or vice versa.

http://www.adorama.com/alc/0013100/arti ... rper-Image" onclick="window.open(this.href);return false;

What does amuse me though is sites that recommend switching off autofocus for macro photography then say use the focus confirmation light in the viewfinder to confirm focus in manual. The focus confirmation light works off the autofocus sensor so it will be no more accurate than leaving autofocus switched on, so ignore it. Using your eye looking around the focusing screen to determine what is in or out of focus in manual mode when close up is the only reliable way.