What camera settings for true looking brightness beamshots?

jimbo231

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I noticed some camera settings make a 200 lumen led flashlight's outdoor beamshots seem like a 35W HID light. I was wondering what settings would make a light look as bright as it would to the human eye? Is that possible or is there too many variables like lens ect?
 

csshih

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plenty of variables, but
most slow shutter speeds, really. :)

just play around with the camera.
 
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csshih

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doh! I read your post wrongly.
I thought you wanted to make it look like a 35W HID.. LOL!

indeed, now it's hard to make it look like what the human eye sees.
 

Chicago_Ted

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I haven't really tried to make beamshot pictures, but in the past I failed at making it look as good as the beamshots the real flashaholics make.

Maybe I should whip out the camera again...
 

MikeAusC

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You have to keep in mind that the eyes sensitivity to light varies greatly, so there is no single setting.

When you're in a room with very bright lights and dvery dim light coming through the window, turn the light off - you won't see a thing. Wait ten minutes and you will see more and more.

If you're trying see how much a torch will make something way in the distance visible, it'll depend on how your eye has adjusted or how much light there is on nearby objects.
 

chenko

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Unfortunately, you canNOT depict perceived brightness with a picture. You can spend some time looking for settings that look similar, but give up on finding a consistent method as it will be impossible for you to achieve this.

Perceived brightness depends on your age, your eyes and your adaption to darkness.

Depicted brightness varies with camera settings, camera's sensor's sensibility and behaviour, demosaicing algorithm applied to the image channels, monitor's color profile and brightness (which is different for everyone of course).

Also, cameras act as non-linear filters too, by compressing dynamic range and at the same time exagerating differences between different shots that in reality look quite similar.

Those are the reasons that brought to the use of "control shots", comparison shots (for tints and beam profiles) etc... It's to show the difference between two things rather than describing them carefully. You add that information to your real-life experience and you have an idea.

I think it is so, but i hope to be proved wrong and that someday someone will come out with a reliable depicting method.
 

gallagho

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One option might be to use something like a P61 as a reference. Setup the camera using manual settings to achieve the best approximation of what is seen by eye, and then keep using these settings for subseqent beamshots. However, if your next beam shot is a Polarion the camera may struggle!
 

DM51

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You can make any light seem as bright or as dim as you like - it is just a matter of adjusting the exposure.

Using a common reference light as a comparison is one way of giving people an idea of the brightness, which is why side-by-side shots that include popular well-known lights for comparison are more useful than stand-alone shots.

One very common mistake people make is to over-expose the center spot of a beamshot, so it is completely bleached out. If you have a 100 lm light with a spot that looks completely white in the center, and then take a shot of a 500 lm light with the same exposure, you won't get a good comparison. The 500 lm light won't look any brighter - it can't! The center spot might look bigger, but on a screen it can't look any brighter than plain white.
 

mtt.tr

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Try a bulb shot for completely variable shutter time maybe smaller aperture to reduce over exposure and you get more stuff in focus
 

cy

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right or wrong... what I've always gone with is standard settings with flash off.

objective is to be consistent ... find one that works and use the same settings for all your beam shots.
 

OfficerCamp

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To compare different lights, you want to use the same distance, same aperature, same shutter speed, same white balance.

To study beam characteristics (or to make the beam look more "natural" as you see it), vary the shutter speed to get the results you desire.
A fully manual mode is useful for this.
 

EV_007

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Over there -- >
I too have tried my hand at representing the beam profiles of various lights, but still not not fully succeeded.

As mentioned, locking down the exposure and WB and shooting a known object with a common light (whatever that may be) and possibly shooting two shots, one exposed for center and other for the spill may yield a more representative shot.

Also outdoor shots tend to provide more information than indoor shots. White wall shots are good for showing tint, if done honestly.

Methods I've used in creating beamshots. (See my gallery in my sig)

1. Use a tripod

2. Play around with shutter and aperture until you get an overall balanced exposure, then lock it in along with white balance and focus if you can. (Start by setting ISO to 400, Shutter set around 1 second and aperture around F5 for a general starting point. Set white balance to daylight, not AWB)

3. Shoot a couple of lights that are well known along side the others at same distance of a common object for reference.

Good luck and have fun. Beamshots take more work than one may think.
 
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