Light source under or over the lens?

I'm contemplating strapping my new flashlights to my camera for night-time photography (local forest areas, wildlife). I wondered if any of the more experienced had an opinion on whether the light source would be better above or below the lens?

Traditionally the flash is mounted above the lens, but with the TK40 and my 100-400mm zoom it would seem sensible in terms of weight to strap it under the camera and lens, attaching to the two tripod mounts.

Never mind... tried it and it's just not bright enough to do what I want without pushing ISO1600. I don't dare go brighter as the TK40 is really bright pointing at any animal, espectially one that is nocturnal, on turbo even rom 100m away.

The colour rendition was surprisingly good though - it's almost as if the supposedly neutral tint compensated for the camera's orangey tint at high ISO.

Position didn't make any difference at that range either.

Rethink time.

At that range . . . I was going to say, yeah.

Night time photography is tricky for sure.

If you have a tripod and can shoot long shutter speeds, then you don't need much light at all.

I used to set up a coleman lantern behind the camera, and that would fill enough glow on the area to do nighttime still life. I used to do it in B&W with 400iso film, it would still look like dark, you couldn't tell it was being lit but there was still perfect composition.

Haven't done anything like that since I went digital tho.
Jsut got a new camera will full manual ability so I'm looking forward to it when the weather gets nice.

To do what I think you are trying to do, you will need a flood with alot of lumens. I'm an incan guy, so the rig I'm putting together to do such a thing will be a sort of Mag623 flood setup. I have a camera mountable flood fixture for video that I can put such a bulb into.

I have mixed feelings on it. I want to animals more than still life, so I want to ideally hand hold at 400mm, which with the stabilisation I've found is managable for me down to 250th ... that's a LOT of light at 400ISO. Unfortunately the mount I've made for the TK40 (a temporary duct-tape job) uses the tripod mount, and whilst it looks pretty damn impressive, it's not as useful as I hoped, plus stops me tripod mounting the camera. I may look at a side-mount, but then the light needs to be aimed in the right place, which will vary with distance. I'm getting about 1/4th on 1600ISO at the range I was thinking of, at which point the movement of the subject is far more of an issue, so this needs a lot more thought.

I will need to talk to the local wildlife experts before I think about cranking up the lumens. Another alternative is use a dual-flash setup and the TK40 for sighting / focus. I have to admit to being very impressed that I can get focus quickly with the AF and the 400mm lens at such long distances. My concern is the wildlife and the stress factors. Getting the shot is for my enjoyment, and I don't want that to be at the cost of the animal becoming distressed. Most of the wildlife around this area is fox/badger/rabbit anyway, so I don't expect to win prizes for this pics!

Generally - lighting is best if above the subject, or over the lens. Think of what you look like if you shine a flashlight under your chin, pointing up. The shadows are wrong. An exception is some of the macro lighting used to eliminate shadows. These can be in the shape of ring around the lens or 2 flashes on either side of the lens ( like they show on the CSI shows )

Good luck with a 400mm lens at night. You are going to have to be really close to the subject for any light to be effective.

Flash plus a "Better Beamer."

Mike beat me to it. The better beamer or maybe I think some thing similar called a project-a-flash. These are a Fresnel lens that mounts to your strobe and can send the light out much further.

I've seen some pretty good shots using it. Here is a review...
http://www.luminous-landscape.com/reviews/better_beamer.shtml

That's sounds like the best Idea right there. I've never used the better beamer. I know my stock420ex speedlight can hit a subject a good 50 feet away as low as 200iso and no less then 1/60 with my 300mm.

If your flash can't perhaps you need a better flash.