Frensnel lense for camera flash boost?

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**DONOTDELETE**

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I built a game camera that takes pictures of deer when they trip the motion sensor but the flash is weak. Someone suggested using a small frensnel lense to amplify the flash. They said it had to be a clear one that would focus the flash. It also has to be pretty small. Any ideas? Thanks, Jeff
 

John G.

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What you need is more light in general. A fresnel lens won't give you that. You need to buy a "slave flash". What that does is it detects your camera's initial flash and then creates another flash nanoseconds later. This increases the overall brightness of the area and with a couple of them, you can get the effect you want. Since there also aren't any wires, you can place them strategically to get the best lighting possible.
 

rlhess

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Jeff,

If your flash is covering more area than your lens, then you can benefit from a fresnel lens. If not, then the only hope is the above-mentioned slave flash. The slave flash, however, my confound the auto exposure system in the camera.

I think we could help more if we knew the camera type, flash type, and lens settings.

There is one semi-commercial thing called a "project-a-flash" that was useful when using 300mm lenses on 35mm cameras. George Lepp's son Tory makes them.

http://www.leppphoto.com/Project-A-Flash/index.html

Enjoy!

Richard
 

PsycoBob[Q2]

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There is also another option- add-on flashes.
If your camera has one of those U-shaped electrical connections on top for a strap-on flash, you can use one. Most cameras with this mount, however do NOT have an internal flash. The mount is supposed to both hold the flash-module and provide the 'trigger' when the shutter snaps. Often seen on more expensive/older cameras, rare now due to built-in flashes being so standard.
 
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**DONOTDELETE**

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O.K. Guys
Here is what I am up against. I am using a Olympus D-370 built in flash camera and if I go with a slave unit I am told it will cause problems because my camera has a preflash and that would trigger the slave unit too soon. I am also try to keep cost and size down. I think the flash is too wide. That is why I was considering a lense to focus the flash more. Any ideas would be greatly appreciated. Thanks, Jeff
 

rlhess

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Jeff,

Does the flash zoom when the camera lens zooms?

If not, then you can use a fresnel lens to focus the light.

The Tory Lepp device is designed for a standalone flash like a Nikon SB-24/25...(I'm dating myself) or a Canon 430Ez.

The problem with the fresnel lens and the built in flash is positioning a big enough one where it will do the most good without it getting in the way of the lens.

If you can turn off the preflash a slave might still be a good idea.

I feel your pain about this. I have a shelf full of camera equipment...this for that and that for this. Each challenge is so easily solved with a dedicated piece of equipment...and when it's camera equipment it'$ u$ually expen$ive!

Cheers,

Richard
 

The_LED_Museum

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Originally posted by rlhess:
The Tory Lepp device is designed for a standalone flash like a Nikon SB-24/25...(I'm dating myself) or a Canon 430Ez.
<font size="2" face="Verdana, Arial">And I thought I was bad... I'm partial to the Honeywell Strobonar 700. Good old fashioned rechargeable "potato masher" speedlight with enough brawn to vaporize typeritten text on a white page!
shocked.gif

Sadly, my beloved Strobonar fell victim to Seismic Sam a couple of winters back.
frown.gif
 
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