Mixing warm white and cool white LEDs (easy mod)

stamat

Newly Enlightened
Joined
Oct 28, 2005
Messages
44
I experimented with mixing Warm white and standard white leds in one flashlight. The resutls were quite interesting.


Findings:
I found surprizingly better depth perception and just ability to "notice" some subtle details. I compared my "mixed led" flashlight with a 0.5W Advancedmart standard white flashlight and there was a considerable difference. Some book cover details consisting of small variations of light brown color are only noticeable with the "mixed" led flashlight. I also opened the kitchen cabinet where we hold the spices and was surprized to notice more detail in the jars with the "mixed" led light. Funny, because the 0.5 W standard white light is actually a little brighter.
I can not explain well the "ability to notice details". It just happens :thinking:.
Maybe I am imagining things :crazy:. Has anybody tried something like that?

Initially I experimented with Warm white LEDs only and found that they were dimmer and at least some of them did not provide good color rendition.
https://www.candlepowerforums.com/posts/1422676



Implementation detail:
This was a low tech real easy mod.
I just added two warm white leds to a flashlight that had three standard white LEDs.
I used two 50 degree Warm white 5mm LEDs from the Led Supply.
The flashlight was a modified bonfire blaze. It has three standard white LEDs - one of the original LEDs and two more wide angle ones from Radio Shack. The Radio Shack leds were good at widening the beam.
I used a Bonfire Blaze, because it is extremely easy to replace the leds (remove cap and desolder/solder).

The leds seem to have similar Vf, because adding the Warm white leds did not change the brightness of the standard white ones. The warm white leds are not as bright and probably contribute about 1/4 of the overal light.

The Black tape on the outside of the cap is to prevent the LEDs from blinding me. The lower end of the cap is left open to light up the ground. The yellow tape on the inside warms up tint by reflecting yellow towards the ground.

The single dark LED is the "Low" setting one.


Question 1:
Ayone knows of a one or two AA battery flashlight with easy to replace 5mm LEDs?
I would like to experiment more. The bonfire blaze is quite clumsy light and not that cheap.

Question 2:
I am surprized that noone has offered (mass produced) a mixed led flashlight. What would be the reason? Peak Led solutions for example could probably easily offer it as an options. It would be ideal for doctors.

Last but not least - I can't help but notice: These are really nice forums. Always friendly, always helpful. Big difference from the photography forum I frequent. People there could easily turn from passionate to plain nasty. How do you guys manage keep the trolls away?
 
Last edited:

chrisse242

Enlightened
Joined
Dec 12, 2003
Messages
899
Location
Germany
Re: Mixing warm white and cool white LEDs

Intersting find stamat. Like many others I've come to like the warmer tints better in the last years. Mixing different tints is a great idea.

Question one: I'd try ebay if I where you. Lot's of cheap 5mm-lights there, and some are easy to open.

Question two: I really don't know. Better depth and colour perception would be a great for many 5mm-lights.

Regarding the trolls: We don't keep them away, we convert them to nice and friendly flashaholics. Well, at least most of them... :naughty:

Chrisse
 

winny

Flashlight Enthusiast
Joined
Apr 14, 2005
Messages
1,067
Location
Gothenburg, Sweden
Re: Mixing warm white and cool white LEDs

Nice findings! Any photos of it?
I once thought about doing the same thing with florescent tubes but looking at their spectral distribution, I understood it wouldn't help. With LEDs, it's a different matter. You probably gained a useful amount of color rendering (perhaps from CRI 70 to 80 somewhere) using two different LEDs.

Question two: Conservative industry (why change when it's already selling?) and cost (can't buy as big quantities of just one LED and you need to feed, keep track of and service your machines with one more component).

Please post here how your mod is progressing. I would love to buy one!
 

stamat

Newly Enlightened
Joined
Oct 28, 2005
Messages
44
Some Photos added to the first post

Will try beamshots tomorrow if anyone is interested.
 

pravardhan

Newly Enlightened
Joined
Feb 1, 2015
Messages
1
Hi,

How about replacing one warm white LED in a string of 11 cool white LEDs?

Will try and let you people know

Bye,
Pravardhan U.S
 

stephenk

Enlightened
Joined
Aug 13, 2015
Messages
761
Location
Brisbane, Australia
I've used multiple flashlights together (a mix of non-high CRI cool and neutral whites) for light painting and you get a noticeable improvement in colour rending of the illuminated scene.
If different tint emitters were used in the same light, I would assume that a diffuser lens would be required for more tint mixing?
 
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