Hello all, I have browsed this site on many occasions and decided to join now, and share in all the knowledge.
I have been a lighting geek for many years and have owned countless flashlights, some stage lights, projectors, a few lasers and a ww2 searchlight.
I have always been most interested in the nature of “beams” weather they be God rays from the sun, a lighthouse, or stage lights at a Pink Floyd concert, and I think it is totally amazing the innovations which have come from the led revolution and by the members of this site and diy’ers all over the globe,so congrats !
My question to get things rolling is…
Has anyone set up a standardized test of distance/throw and beam power combined?
Something like “at 300 meters , the beam spot, (or diameter) equals x Feet/inches wide, and the intensity measured on a light meter at that distance equals x when the meter is placed directly in the beam path.
If so I would like the link to the instructions for a test of this type, or otherwise I think it would be great to create one, with suggestions from all of you,of course.
The standard calculation for throw has beam intensity included in it. So, the throw is the measured distance at which the light intensity becomes X amount. Beam angle can also be measured, but not too precisely. I guess you can get really close to calculating supposed beam width at a specific distance, based on the beam angle, but it won’t be very accurate, I think.
EDIT: Here’s an old thread that can help you some. LINK
-Thank you Davidef I appreciate the reply and link to the mathematical calculations and associated theory,I am sure this info is very helpfull for many.
Unfortunately I flunked math (not really) but I am more of a real world scenario kind of guy ,trial and error as opposed to math and theory, as many things in life have had millions spent to solve in a lab, and abandoned later due to things not working in a real live Scenario.
So what i am proposing is you and another light geek like yourself (or perhaps a grumbling spouse asking why?) go outside to a football field ,a open road ,a deserted landscape, measure off x amount of meters from a vertical surface and you …at one end and geek friend at the other with a tape measure and light meter and record the data of the beam falling on the vertical flat surface.
the main reason for this approach is that
A This is the actual fact of the matter, there in front of you to see ,no excuses no regrets.
B A person may then make adjustments to focal length of source to reflector ,or optics ,and try again to achieve hopefully better results.
C Existing production torches may be proven or dis-proved on this data
D Modders may then have a baseline to work from.
I hope some of you may agree this would be very helpfull data for all of us,so let me know what your thoughts and suggestions are.
Well… I have given this idea 2 weeks to incubate, and I must say I had hoped someone would have at least been able to provide a little bit of data… of some form, to kick off a compilation list, cant really figure it?
I see lots of threads with claims… and beam shots , and no real data to backup the lumens/candela/mcd/etc.
of the actual end product of the beam, at the throwing end point.
I think this exercise would be comparable to the use of an integrating sphere in a lab ,when used to measure total output of a source ,but tailored more to the interests of people of this forum?
Please mind you , I have much respect and admiration for the innovation and intensive data which has been produced by many on this site.