Telephoto flash – what are you using?
A lot of interesting mammals are nocturnal, or are best seen under difficult lighting conditions.
One approach is to rely on the spotlight that are used by wildlife guides during night drives. In Sabah at Deramakot or Tabin this is mostly what I did, and have used this approach in Africa as well. It can work, but it usually requires very high ISO on the camera. Also, the guides lights vary quite a bit. I have found that LEP (laser excited phosphor) flash lights are better in brightness and color temperature than any of the big guide spotlights, but they have a very narrow beam.
My go-to lens for night drives is a 600mm f/4; one can get a faster lens at shorter focal lengths, but the subject becomes very small in the frame.
Some on-camera flashes (aka speedlight) such as the Canon EL-1 or the Nikon SB5000 will automatically zoom out to 200mm focal length. I have also tried this, and for relatively short distances, at moderately high ISO it will work. An animal in the road, or at the side of the road, is often close enough for this approach. But things farther away, or way up in a tall tree (like in Sabah) usually puts the subject out of range.
Having the flash zoom to an approximate field of view of 200mm is still way too broad for a 600mm but for fairly close animals it will work better than a conventional speedlight (which tends to zoom to 100m).
The “better beamer” and several similar attachments add a fresnel lens to a standard speedlight with some velcro and elastic bands. The good news is that these are cheap. That’s also the bad news – they are flimsy and fall apart, or droop enough that the beam misses the subject. This tends to happen just when you need them – at least for me.
I decided to design my own system, which is picture here. It is based on a 6 inch diameter carbon fiber tube. Inside is a Godox AD 200 Pro flash, which is about 2X the power of a typical on-camera speedlight. It does wireless TTL with a transmitter on my Canon camera – but would work with Sony, Nikon or just about any other recent camera with the appropriate.
Yes, it is huge and bulky, but it is very light – it hardly weighs more than the Godox flash unit. Later this week I will take it to Zambia and Zimbabwe for a month.
The downside of a flash like this is that you can get incredibly strong eye-shine from the subject. But the only way to prevent that would be to have the flash pointed by an assistant that was not near the photographer. That obviously does not work for most night drives.
One other point is that this sort of system can also work as a fill flash for animals in shade. This is particularly true for mammals with dark fur in the shade – they can be like the proverbial black cat in a coal bin at midnight. I hope to photograph a black leopard later this year, and this is a consideration.
Some people worry that flash will harm an animal’s eyes. So I decided to check this out. In case it is of interest to people on the list, here is what I found.
First, if that were true, then fashion models or celebrities would retire blind from all of the flashes from red carpet appearances and photoshoots. They don’t because the flash is actually less light you typically get from sunlight, so it is not harmful to human eyes. That is also true for mammals – even nocturnal ones – because they are invariably able to be in daylight without harm, even if that isn’t their typical habitat.
This study https://zslpublications.onlinelibrary.wiley.com/doi/pdf/10.1002/rse2.243 for example, concludes that white light flash on camera traps in caves is “minimally invasive” for hibernating bats inside caves. For large mammals, this recent (2021) Norwegian master’s thesis says there is no statistically significant impact of white light flash https://www.duo.uio.no/bitstream/handle/10852/86599/thvalle_master.pdf?sequence=1. The context is behavioral studies for camera traps but it seems quite relevant. This 2021 paper from Italy has a similar conclusion for urban mammals http://www.italian-journal-of-mammalogy.it/A-shot-in-the-dark-White-and-infrared-LED-flash-camera-traps-yield-similar-detection,136508,0,2.html .
Second, the exposure on the camera is an independent source of information that this isn’t the case. Let’s say you put a spotlight on an animal and the camera’s internal light meter says you need a 1 sec exposure without flash. That’s too long to get a good picture; a flash will make that take 1/1000 of a second. But assuming the flash reaches the same exposure, the total amount of light is the SAME. The impact of light on a retina, or a camera sensor, is about the total amount of light delivered.
One can always posit that the animal might have a momentary dazzle from the flash, but they will get that from the spotlight also. Spotlights during night drives generally linger for much longer than just the exposure time.
Net-net, I don’t think that flash is a significant harm on the animals that I go to watch and photograph.