Continuous LED Lighting?

SamirD

Has anyone considered using a product like this to just bask a night subject in some soft lighting?



My old-as-dirt cameras can't do anything above ISO 200, so I'm trying to think of some creative ways to get the night shots I need without having to resort to 20-30 second shutter times. If I could use something like this and then cut my shutter times down to a 4-5 seconds, that would be nice. Flashes tend to be too harsh on the subject--cars--which need a soft light. And an appropriate flash setup that could be triggered by my cameras would probably be too pricey.

I might be trying to make a miracle out of duct tape, but it can't hurt by asking. Someone called me the McGuyver of local photographers this weekend. :rofl

mercphoto

But is that big enough to be a soft light source for a car? How much bigger is that light source than your flash head? I'm thinking it might be better to build or buy a big diffuser for your existing flash. I've heard of people using white bed sheets on large frames made from PVC pipe to difuse a flash with.

ziggy53

mercphoto wrote: »

But is that big enough to be a soft light source for a car? How much bigger is that light source than your flash head? I'm thinking it might be better to build or buy a big diffuser for your existing flash. I've heard of people using white bed sheets on large frames made from PVC pipe to difuse a flash with.

Absolutely true. Relative light size is extremely important. Continuous spectrum is another important factor that LED light sources lack. Total power output is another deficiency for LED lights, compared to electronic flash.

ziggy53

SamirD wrote: »

Has anyone considered using a product like this to just bask a night subject in some soft lighting?
...

My old-as-dirt cameras can't do anything above ISO 200, so I'm trying to think of some creative ways to get the night shots I need without having to resort to 20-30 second shutter times. If I could use something like this and then cut my shutter times down to a 4-5 seconds, that would be nice. Flashes tend to be too harsh on the subject--cars--which need a soft light. And an appropriate flash setup that could be triggered by my cameras would probably be too pricey.

I might be trying to make a miracle out of duct tape, but it can't hurt by asking. Someone called me the McGuyver of local photographers this weekend.

Feel free to try. McGyver would use home made flash powder, no doubt.

SamirD

mercphoto wrote: »

But is that big enough to be a soft light source for a car? How much bigger is that light source than your flash head? I'm thinking it might be better to build or buy a big diffuser for your existing flash. I've heard of people using white bed sheets on large frames made from PVC pipe to difuse a flash with.

I'm not sure if its enough light so that's why I'm asking. Right now it's just ambient lighting that used to light the field, so it would be used more like a fill light than anything.

It's a lot bigger than the built-in flash head on my sony dsc-f828, which is the camera I use for most of my night shoots. I have a small puffer-style diffuser for the built-in flash, but flashes tend to cause reflectors in the light assemblies to light up and look unnatural. I don't want to have to carry too much. Before I saw this, I was actually thinking of just doing some light painting using a flashlight since the exposure is so long.

SamirD

ziggy53 wrote: »

Absolutely true. Relative light size is extremely important. Continuous spectrum is another important factor that LED light sources lack. Total power output is another deficiency for LED lights, compared to electronic flash.

I end up messing with the white balance manually anyways, so I could compensate for any odd color issues. I know the power output is going to be much less than a burst from even the built-in flash, but my thoughts were that if I had a light bulb as a light source, it would make a night and day difference.

ziggy53

SamirD wrote: »

I end up messing with the white balance manually anyways, so I could compensate for any odd color issues. ...

A discontinuous spectrum can not be easily compensated. You would have to know the nature of the spectrum and any major breaks in the spectrum would not be represented at all. (The image might be effectively "color blind" to some shades and hues.) You cannot compensate for what is not there.

Typical "white" LED spectrum (Note the spikes and gaps):

http://upload.wikimedia.org/wikipedia/en/thumb/f/f4/Red-YellowGreen-Blue_LED_spectra.png/800px-Red-YellowGreen-Blue_LED_spectra.png

SamirD wrote: »

... I know the power output is going to be much less than a burst from even the built-in flash, but my thoughts were that if I had a light bulb as a light source, it would make a night and day difference.

Feel free to try it. You may see some addition of illumination but a long exposure will mean that it will have to "compete with", or compliment, ambient light. Once you know the level of the ambient light and you know the illumination of the LED light, you will be able to calculate the ratio and determine the suitability. Figure a way to measure the ambient and the LED contributions.

As you already read from both Bill and myself, the effective size of the light "is" important. This LED light will not necessarily be much larger in effect than an electronic flash used directly. Use a diffuser large enough to meet your needs. Practice with your own vehicle, or any vehicle, in similar circumstances, and then apply that knowledge and experience for your intended subject vehicles.

SamirD

ziggy53 wrote: »

A discontinuous spectrum can not be easily compensated. You would have to know the nature of the spectrum and any major breaks in the spectrum would not be represented at all. (The image might be effectively "color blind" to some shades and hues.) You cannot compensate for what is not there.

And the same thing happens with sensors as the light levels go down--they become a bit color blind as well. I find that reds become more pronounced, and there's more of a yellow/tungsten hue if I let the camera determine what it thinks is the right while balance. Very interesting graph of the LED spectrum, and I'll keep that in mind.

ziggy53 wrote: »

Feel free to try it. You may see some addition of illumination but a long exposure will mean that it will have to "compete with", or compliment, ambient light. Once you know the level of the ambient light and you know the illumination of the LED light, you will be able to calculate the ratio and determine the suitability. Figure a way to measure the ambient and the LED contributions.

There's no real way to measure this accurately without a light meter. Each shot needs to be done as fast as possible, so my thoughts were that a steady light source might be easier to 'eyeball' exposure than trying to figure out flash settings by trial and error.

ziggy53 wrote: »

As you already read from both Bill and myself, the effective size of the light "is" important. This LED light will not necessarily be much larger in effect than an electronic flash used directly. Use a diffuser large enough to meet your needs. Practice with your own vehicle, or any vehicle, in similar circumstances, and then apply that knowledge and experience for your intended subject vehicles.

I didn't think the LED would be brighter or more intense. If anything, it would be the opposite--especially on a long exposure. I've played with the small diffuser I have with the on-board flash set to fill-in, but it still is too intense even on its lowest setting. That's why I was thinking of going with an ambient light source versus designing some sort of bulky diffuser.

Some great feedback as it's got my gears turning in directions I didn't think of.

SamirD

Here's what I currently have for a diffuser:


What do you guys think of these products? I know some are made for a dedicated flash so they would need 'adapting'.
http://www.bhphotovideo.com/c/product/621567-REG/Interfit_STR111_STR111_Strobies_On_Camera_Small.html
http://www.bhphotovideo.com/c/product/738212-REG/Zeikos_ZE_SBD_UNIVERSAL_SOFT_BOX_FLASH.html
http://www.bhphotovideo.com/c/product/388057-REG/LumiQuest_LQ051D1.html
http://www.bhphotovideo.com/c/product/621592-REG/Interfit_STR103.html