Focusing of flying insects

yesterday there was a Bumble Bee flying around the yard, It was mostly flying a small circle and hovering in one spot, it did this for about 5 hours, no clue what it was doing, So I was trying to take some shots of it and for the life of me I could not get a focus lock on it even though it was fairly stationary , I could get a manual focus on it, What technic do you use in this situation? Was using D750 70-200 E., no trouble focusing on anything else.

Use manual focus/manual exposure and pre-focus on a spot where you think the bee will eventually show up. Come to think of it, this works for just about anything thats moving.

What's the background like?

 

Auto Area and Group Area focus modes take the 'closest' lock on any AF Point covered, so if you're nearly there, maybe via the focus limiter, it should pick it up.

 

EDIT....What body are you using?

Edited May 24, 2020 by mike_halliwell

What's the background like?

 

Auto Area and Group Area focus modes take the 'closest' lock on any AF Point covered, so if you're nearly there, maybe via the focus limiter, it should pick it up.

 

EDIT....What body are you using?

D750

These are difficult to focus on as they are usually black and if something is lighter close by the AF might lock onto it. If you are using Nikon DSLR that has Group AF try it. (D500, D810, D850 to name a few.) Or D9 of D25. Or manual focus which is what I use a lot on bees. I preset the focus, set AF-C to the fastest fps my camera allows. Then as the bee comes into the area where I have pre-focused I fire away and I move the camera in and out a bit to increase my chances of getting one in perfect focus. Its not perfect but it often works better than AF.

Use manual focus/manual exposure and pre-focus on a spot where you think the bee will eventually show up. Come to think of it, this works for just about anything thats moving.

it would hover in one spot for about 10-15 sec and I could get my AF point on it but would not take focus, at first I thought I was too close but I was about 8 ft away.

These are difficult to focus on as they are usually black and if something is lighter close by the AF might lock onto it. If you are using Nikon DSLR that has Group AF try it. (D500, D810, D850 to name a few.) Or D9 of D25. Or manual focus which is what I use a lot on bees. I preset the focus, set AF-C to the fastest fps my camera allows. Then as the bee comes into the area where I have pre-focused I fire away and I move the camera in and out a bit to increase my chances of getting one in perfect focus. Its not perfect but it often works better than AF.

Thats what I was wondering if the Color (black) of the bee was the problem.

With a manual focus lens, you either have to catch the bug(ger)s at rest or for action, you have to pre-focus and wait for the creature to fly into the depth of field.

With Automatic Focus, you have to watch out and take lots of shots (in my experience) since the lens just is not usually intelliget enough to distinguish what YOU want in focus. It's also best if the lens allows manual adjustment in AF mode.

Was using D750 70-200 E.,

It's a bumble bee, so perhaps you were trying to focus at less than your len's minimum focus distance of 3.61 feet? You will do better with a macro lens. Good luck

A big zoom might not be the best choice for this.

at first I thought I was too close but I was about 8 ft away.

Sorry I just saw this now. To rule out mechanical problem, perhaps try focusing on something bee-size at similar distance?

 

If that is not a problem, then would it be your auto focus setting? I don't have experience with D750, but found this tutorial on its focussing system:

 

I think there may be something on the wing beats at a weird frequency that messes with AF.

 

Maybe a sub-set or a harmonic with AF refresh rate?

At 8' and a small subject, you may well have something that's too small for the AF point to lock onto, and that would be while the focus is close - if the AF goes some distance away, all it will see is blur.

 

Like others, I've just made sure I have the focal plane in the right area, then shot bursts with the focus disabled until the subject hit the focal plane. You may want bursts to time the wing position anyway. At least a fairly stationary subject helps - I've had a miserable time chasing flying dragonflies and even butterflies against a busy background, and even getting a swarm of gnats that were perfectly backlit with a 300/4 was quite challenging.

 

In theory there ought to be a chance that trap focus may help, but for some reason I believe it's only an option with a single focus point, and even then I'd certainly not bet on it with a small, fast subject.

 

Good luck. :-)

My personal experiences have been iffy using AF for small moving objects, especially with a zoom. Much better experience with manual focus walking into and out of the point of focus. If you're pretty certain of capture at a specific distance, prefocus on that area. The exception has been dragonflies in late fall, when they are slowed down by cold weather...in those cases AF worked just fine.