Ronaldo

Some reaction Wilson, here we go
Would you use a flash on your baby child? Probably in some circumstances, but you would take care of not using a high intensity one, and you would probably use bounced light and other methods to diffuse the strength and take care of the composition. Now, would you/others use the same care for a bird? May be a lot of photographers would not, when they don't have a long time to take a shot at a skittish bird. I would rather use a high ISO and have a blurry/grainy record shot than causing potential damage, as a rule of caution. Direct flashes can cause serious injuries to eyes, of birds as well as humans or other animals.
Now, what to do in cases where high ISO photography is impossible? I would prefer a (not too strong) torch light. Initially disturbing, the bird eyes can progressively adjust and don't suffer from sudden and unexpected strong flashes of light. However, it is not easy to know what disturbs a bird, so better in any case to minimize the number of pictures taken and too bad if the picture is not an award-winning one. It seems to me that 30 pictures with flash is a lot but if the birds were not disturbed and you were careful on the way the flash was used and directed, then I am not opposed to it.
In regards to the behavior of people, rushing for a bird in Long Valley or Po Toi, it's a bit easy to condemn them, but disturbed birds usually quickly leave the place. If they stay, it may be because they are sick or used to human presence (or human feeding). Hong Kong is mainly a place of migrants/vagrant birds. I don't think that the relatively low number of breeding or resident species in Hong Kong is due to photographers but land planning decisions (anti-conservation and pro-property developers). I doubt photography clicks would harm or disturb birds, and I have not seen a bird leave because of the clicks themselves, but I have seen a lot getting disturbed by the loud discussions of photographers/birders.

Ronaldo

Here we go, with the polemics...

"Would you use flash on your baby child" - yes, lots of times. They are now 16 and 20 years of age respectively with perfect vision. No, not bounced, but straight, normal flash. Blurry, grainy shots of my kids were of no use to me. Lots of people are photographed with direct flash every day. If it were a health hazard it would have been banned a long time ago.
=> your children are very lucky. Do you want me to experience on your eyes? And you can ask my doctor about that. I had to do an eye operation recently and he asked me about that. So, yes, you should perhaps inform yourself first

"Direct flashes can cause serious injuries to eyes" - we aren't talking high powered lasers here, we are talking normal flash. You seriously think that the power of a normal flash is any greater than that of a fairly close lightening burst? You can cite any scientific paper in which the flash of a normal sized flash gun, used to achieve a normal photographic exposure, is recorded as causing serious injuries to eyes?
=> what about all the stroboscopic warning provided at the BBC and other serious TVs when there is excessive flash photography. And here we don't talk about the person directly being flashed, but about people watching it indirectly on TV.

"Disturbed birds usually quickly leave the place" - unless they are exhausted and "the place" has the only food source known to them.
=> give me examples, if you are that sure about that.

"I doubt photography clicks would harm or disturb birds" - there's no doubt in my mind, I've seen it often enough. Single shutter activation, no, high speed motordrive on a close bird, quite possible.
=> close presence by the birder is probably as disturbing as the shutter activation. Have you thought about that? And why do yu use a car to get close to the bird, if not because that car provides a hide against human presence. I don't think you car changes the sound of your camera.

Ronaldo

now obviously, if we talk about one person using a flash once on a bird or a person, I don't think it can cause any issues. I doubt however that it is the case when you have twenty photographers taking photos of a single subject with flash.

And I don't think you experienced that with your children, either.

Ronaldo

Martin, Let's stop the talk and go to something more serious:

You take pictures of me with high shutter speed at your will, while I take pictures of your face with a telephoto and a flash. Let's see who will feel more discomfort first.
As I mentioned, a single flash is just a bit disturbing and I doubt you would submit any of your children to 30 flash shots using a high guide number flash in a row in the same conditions as you say you would for a bird.

If you want to arrange a meeting, just pm me and I am happy to accommodate.

Thanks

Ronaldo

yeah! Fight to blindness and deafness!

more seriously http://en.wikipedia.org/wiki/Flash_blindness
and found 3,180,000 results for "flash photography retina"

and no results on wikipedia but still 2,680,000 results for "high shutter speed deafness"

Ronaldo

You have to stand up out of your car! You can use your headlights to distract me!

Ronaldo

Talking about using fill-in flash clearly doesn't bring anything to this thread.
Fill-in flash clearly has minimal consequences, aside from the small disturbance which results, as you put it yourself, in "50% of the birds flying away after the first firing". I guess you must have good reasons to continue to use a flash after that.

Scientific evidence is very clear and again, just experience it on yourself: flash photography of birds or other animals/humans in low light conditions make them blind for at least some time. This purely physical disturbance is enough for me to try to restrain as much as possible from the usage of flash, in particular with a subject who clearly doesn't care about any of us taking a picture of him. If you put more interest in the quality of your photos than in the welfare of that involuntary subject, then it's a problem between you and your conscience.

Sharkfin soup is perfectly legal in Hong Kong, so eat it at will.

Ronaldo

Obviously I have to incline myself in defeat in front of such a strong argument as a photography taken with a flash, similarly as i would about the subject of bird nest disturbance by photographers, in front of the photo of a cute little chick.

Martin, seems that you were much more reasonable in 2007. Is it age or experience?

Anyway, Wilson, in case you want to read further, my half-penny worth of an old discussion

http://www.hkbws.org.hk/BBS/view ... ghlight=photography