USM - Heavily flawed?

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Steve
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Hey guys

I am new here so don't know if this has been discussed before.

My dog is a neurotic border collie and is terrified of thunder, fireworks and Ultrasonic lenses!! From far far away she hears it, be it micro motor or ring type and it sends her in the opposite direction. Arc drive motors have no effect on her.

So it got me thinking, she can't be the only animal hearing it?

So to test I snuck up on some squirrels, aimed, manually focused and fired of a few shots. Then I tried auto focusing and BAM off they run. This was with a 70-200mm F/4L. Reasonably close, maybe 20 metres.

Has anyone else noticed this?
 
If that'll work on cats in my garden I'll be more than pleased :D
 
Last time I was out shooting squirrels with my 70-200 f4 L they were about 3 feet away and it never bothered them a bit. As soon as I got to the regular spot they were running around and only disappeared when there was any dogs around. I even had one climb up my leg while I was taking another about 15 feet away.
It doesn't bother my cat either, unless it makes him roll onto his back waiting for his tummy tickled. Can't sat I've noticed USM have any effect on any wildlife to be honest. It normally makes people turn away more than animals.
 
Thanks for the response.

I am certainly not making it up, I reckon it's worth keeping and eye on when things run away.

Anyone else noticed this phenomenon?
 
Been using USM lenses since the mid-90s and never noticed this at all... perhaps it's particular to the lens(es) you're using in combination with your dog?
 
Pity I wasn't using my camera when I got bitten by a Border Collie last year then

Thought they were ok as dogs go, but from what i've read and heard they can be a bit mental, at least it wasn't a child and thankfully the responsible owner took the correct course of action
 
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Hey guys

I am new here so don't know if this has been discussed before.

My dog is a neurotic border collie and is terrified of thunder, fireworks and Ultrasonic lenses!! From far far away she hears it, be it micro motor or ring type and it sends her in the opposite direction. Arc drive motors have no effect on her.

So it got me thinking, she can't be the only animal hearing it?

So to test I snuck up on some squirrels, aimed, manually focused and fired of a few shots. Then I tried auto focusing and BAM off they run. This was with a 70-200mm F/4L. Reasonably close, maybe 20 metres.

Has anyone else noticed this?

Do you not think that this is more likely to be because all animals have different sensitivity to certain frequencies of sounds- often fairly generic in who is affected by a specific range but not unusual to be individualistic either?
eg some people can tolerate fingernails on a blackboard and other people find it painful to listen.
I know a dog who doesn't like the sound of the hoover but fireworks- what fireworks?- doesn't even notice them:lol:

There is not enough isolation with your squirrel test for it to be of any scientific merit I'm afraid so I'm not sure I'd fund your PhD just yet- I'm out:D
 
Never noticed this, but we did have a Siamese cat that was petrified of the vacuum cleaner. He'd bolt, and hide, before it was even switched on.
 
Yeah perhaps the squirrel test wouldn't stand up to any scrutiny..

As for my dog, she sees the camera and starts to look panicky and then the second USM kicks in she is gone. If she hasn't seen the camera she still bolts at the sound of focusing. It is the same for the flash charging (even my "silent" 430EX II).

Regarding my dog, it's all USM lenses that I have tried, 50mm F/1.4, 70-200mm F/2.8 and F/4 and I was even trying to fix an ancient 24-80mm that wasn't auto-focusing but was apparently still making a noise when I pressed the button.

So it doesn't SCARE all animals, but I would bet money that most can HEAR it.

I tried but failed to find a definitive frequency of USM, I seem to remember it was 33kHz.
 
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