Powerful focus light instead of strobe?

[john70490 3]

I've just bought a Panasonic DMX-GF3 with the 14-42mm zoom lens (new display item in mint condition at a bargain price) and a Meikon-36 underwater housing as a back-up for my Nikon D300/Ikelite set-up. For those not familiar with the camera, it is a fairly basic but quite capable four-thirds mirrorless camera with HD video. The housing is a cheap Chinese polycarbonate housing with a cold shoe. There is no hot shoe so my possiblities of using a strobe are limited. I could possibly rig a make-shift fibre optic connection - the housing has enough space for the camera's built-in flash to open a few millimetres, which is enough for the flash to fire - but to start with I plan to try using my La Luz optics C-800 light, which has a powerful (maximum 800 lumens), even beam without a hotspot (I have the necessary hardware for attaching it). I'm pretty sure this will work for close-up video but will it work for close-up / macro still shots? I can set the camera's ISO setting to 600 without significant noise, so would f8-11 and aperture priority produce usable images? Grateful for any thoughts.

Edited March 28, 2013 by john70490

[jahjahwarrior 10]

For close up shots I've gotten good results from a powerful light and no strobe.

 

One thing I've been impressed with is just how fast and powerful strobes are. Strobes will make a full power flash in under 1/250 second--DS 125 is 110 watts. (Assume 100%of electrical energy is turned into lumens) I used to use a 12 watt light- in those same 1/250 seconds that 12 watt light only emitted .048 watts. 110 vs .048.....

 

Ikelites EV controllers give great control with optically synced strobes.

[billmackbarnes 0]

Can you raise your flash inside the housing? If you can the flash enough for the flash to work, strap a fiber optic cable and use a real strobe. A focus light is fine for video, but nothing comes close to the quality prints produced by a strobe.

 

Bill

[john70490 3]

If I decided to use a strobe (one of my DS51's), I would buy Ikelite's fibre optic adapter #4401. However, the camera and housing (with built-in port) is a very compact and light set-up (weighs less than 1 kg) and adding several kilos of strobe and arms with clamps seems a little silly if I can get acceptable results with my powwerful focus light and Ultralight ball mount.

[john70490 3]

Yes, Bill, as stated in my post, "the housing has enough space for the camera's built-in flash to open a few millimetres, which is enough for the flash to fire".

[ChrigelKarrer 52]

The internal strobe of your camera have to be completely open or the strobe diffuser completely visible, if you fire it not at all open you risk a fire and you will burn your internal strobe after some use.

You can do a test - under your own responsability - to fire the internal strobe holding your finger in front of the open strobe and you will feel the intense heat.

Nikon cameras have a switch to enable the internal strobe only if it is completely open to avoid this problem and i am sure that somewhere in the manual of your camera

is a bold remark to not fire the strobe if not completely open.

If the internal strobe open enough to see the whole strobe diffuser you can use any optical triggered slave strobe, my recommendation is one of the INON models

 

Anyway and as already wrote above, a torch of whatever style is not powerful enough to illuminate anything farther than 50 centimeters o 2ft far from it and ofthen they leave a ugly

hotspot in the picture.

 

Chris

[john70490 3]

Thanks Chris! The minimum working distance of the lens is 30cm, so I was thinking of a maximum distance of 50-60cm with the lens at the 42cm setting (equal to 84cm for 35mm film). I doubt if there will be an ugly hotspot under those conditions as the beam is even and wide enough to fill the whole frame. I do realize that a strobe would be a better option in many ways and would naturally not consider using the focus light instead of a strobe with my D300 but I was hoping it would work sufficiently well with the Panasonic GF3 to provide a useful back-up system. Am I asking too much of a set-up that cost me less than $450 (the price for the camera, lens and u/w housing with a built-in port)?