Studio light comparison chart

The studio strobe options are daunting to me. Has anyone ever seen a comparison chart? Would anyone be interested in contributing if I began compiling such a chart?

A great idea! It should include all brands, types of light sources (natural/artificial, continuous/strobe). I imagine a comprehensive table or two, including features, attributes, and suitable applications.

I expect it to be a monster table and a herculean task to make it.

Since it's going to be a universal chart. I would have everyone send in the data based on a similar ev value. Let's say report findings using an ev value of 8 that way when you compare it doesn't matter if the unit is rated as watts or anything else you know to get an ev value of 8 it took this much power at this distance bare or. This with this modifier.

Blackey Cole wrote in post #18240668
Since it's going to be a universal chart. I would have everyone send in the data based on a similar ev value. Let's say report findings using an ev value of 8 that way when you compare it doesn't matter if the unit is rated as watts or anything else you know to get an ev value of 8 it took this much power at this distance bare or. This with this modifier.

This has already been done for my system: http://hensel.eu …-light-former-comparison/

Not sure one could appropriate/incorporat​e it, though.

One issue is simply that output depends upon the reflector design, and reflectors fill widely different areas (angular coverage).

Decades ago, Chimera published a brochure with a large number of 1000 w-s units used in one of their softboxes, so that was a great equalizer that could compare many units directly.

As Wilt points out, the only way to build a truly comparative table of lights is to place a modifier in a studio or other room setting without any outside light sources, then place each light into the modifier in EXACTLY the same position.
Make an raw image at a specific exposure setting with the same camera/lens combination. The image must include, in EXACTLY the same location, a standard color chart that includes a grey scale.
Create a camera calibration file for Lightroom or whatever processing software using the same modifier.
Once the image files are transferred to a disk import them into a the processing software library.
Apply EXACTLY the same processing parameters and then read the color chart mid-tone grey square.

In my view, that's the only way to create a comparison chart, standardize everything so that the only variable is the light source in the modifier.

Whoever wants to undertake the effort, good luck, and I look forward to your results.

Another thing would be to evaluate each light's actual colour temperature and how much it varies at different power levels. This would separate the good units from the bad and the ugly. Alas, this would be another monumental task.

I was thinking about general features and capabilities for starters. Any suggestion on those to put in the chart?

KatManDEW wrote in post #18241425
I was thinking about general features and capabilities for starters. Any suggestion on those to put in the chart?

Power (watt-seconds)
Number of Channels
Range of Power levels per channel (min-max)
Adjustable power for fractional f/stops (y/n) power level increments (EV)
For units with >1 channel, whether Channels are Symmetric/Assymetric
Modelling light (y/n), modelling light power level(s)
Power source (AC/internal battery/external battery)
Head has cooling fan (y/n)
Slave mode type: (radio, optical)

Thanks, Wilt, that's a strong start. A second table might be modifiers (BD, SB, silks, etc) in both branded and generic forms. Besides products, I would like a third table of physical light sources (sunlight, LED, sodium vapor, xenon flash, tungsten, etc) and their photographically-relevant attributes. All these tables can be constructed by us as a group without laboratory-grade instrumentation. I'm a measurement freak and have things like color flashmeters, but admit that it's tedious work and not particularly helpful for real photogs making decisions about light generation.

I see about three days of work.

Wilt wrote in post #18241459
Power (watt-seconds)
Number of Channels
Range of Power levels per channel (min-max)
Adjustable power for fractional f/stops (y/n) power level increments (EV)
For units with >1 channel, whether Channels are Symmetric/Assymetric
Modelling light (y/n), modelling light power level(s)
Power source (AC/internal battery/external battery)
Head has cooling fan (y/n)
Slave mode type: (radio, optical)

Fantastic! Exactly the kind of things I was thinking about.

Any suggestions on the format for the document, and where to store it. Maybe a spreadsheet on Google Drive?

RicoTudor wrote in post #18241467
Thanks, Wilt, that's a strong start. A second table might be modifiers (BD, SB, silks, etc) in both branded and generic forms. Besides products, I would like a third table of physical light sources (sunlight, LED, sodium vapor, xenon flash, tungsten, etc) and their photographically-relevant attributes. All these tables can be constructed by us as a group without laboratory-grade instrumentation. I'm a measurement freak and have things like color flashmeters, but admit that it's tedious work and not particularly helpful for real photogs making decisions about light generation.

I see about three days of work.

Is that three Venus days (which takes 243.025 Earth days to rotate once)?

RicoTudor wrote in post #18241467
Thanks, Wilt, that's a strong start. A second table might be modifiers (BD, SB, silks, etc) in both branded and generic forms. Besides products, I would like a third table of physical light sources (sunlight, LED, sodium vapor, xenon flash, tungsten, etc) and their photographically-relevant attributes. All these tables can be constructed by us as a group without laboratory-grade instrumentation. I'm a measurement freak and have things like color flashmeters, but admit that it's tedious work and not particularly helpful for real photogs making decisions about light generation.

I see about three days of work.

Color meter measurement at each setting (you would want several pops at a given setting to verify consistency) would, indeed, be mind-numbing work, at least by the fifth light. And we would need to account for how long they had been on, how hot they are, etc .

The table of modifiers would be useful but imagine trying to compile it. Elinchrom, for example, would be easier because there are relatively fewer third-party options. But Bowens would be a nightmare to track, given all the new options someone creates in China each month. Then there are units like the Godox AD360--there are a few modifiers you might not be able to use, but with an adapter it will go in almost anything fairly easily. Given three days and Rumplestilskin at the door, I'd be worried. .

Plus, are we limited to current production or including items on the used market?

Useful but hard task to complete.

As for photographically relevant characteristics of physical light sources, what do you have in mind?

Sun--kelvin temperature varies dramatically from blue hour to golden hour to noon (is it cloudy, raining, snowing, how much...) back to golden hour and blue hour. Sunny 16 rule, more or less. Hard or soft source depending on cloud cover or other "modifiers." Location has an impact (latitude, air quality, time of year). I'm confident the sun gives us a book or two by itself.

Fluorescent--what a nightmare it can be with the blue, green plus drop out not to mention variations within one type due to age of bulb, how long it's been on, etc. And the large variation of types which exist. And...

Three Venusian days...and a team of graduate students from RIT ...maybe .

Kidding aside, the compilation is worthwhile but setting the scale and goals for the task itself is more complicated than it seemed at first.

You could host a get together and everyone bring their lights and setup a set using a standard 7" reflector that most have. Then do the test publish your setup so others areas could do the same and they add to your list the lights they test try to have overlap within each groups plus wit each test. If you have three of the same light test each then if the next group has three of the same light the test for comparison then the rest will be valid and if their three lights happen to be different but they do test one of the other groups three light standard and get similar results the the others results should be valid. The more groups doing the test the larger the results and easier it will be to get a variety of lights.

A second approach would be start a lighting blog do several tests and demo posts a few non biased test of gear you already possess and can barrow locally then contact the manufacturers and explain to them the goal of your test and that if your results vary from their claimed output you will let them know and retest if they desirewith the same or new equipment.