Everything you 4 just said
Yes
And the beam pattern looks like the ones I hate from your typical USB light. Not one of the nice Euro lights like B&M or the like.
Well any dynamo light which advertises their 700 lumen count doesn’t really know shit.
first thing I noticed was the beam pattern. I road with the IQ-X for the first time last night and holy shit, that’s impressive stuff. I had no idea what dynamo was gonna be like in real life and was totally blown away
That was my red flag too.
Could you elaborate on that? Is this about lumens vs lux? I just don’t know anything about it and would like to know more
IIRC lumens is a measure of how bright the light source is, whereas lux is a measure of how much light actually gets cast onto (object)
Like, lumens doesn’t take into account the beam pattern and lens design, whereas lux does.
(I think.)
Lights advertised by their lumens are all in a brightness war. Ni mention of the beam pattern quality. Having a million whatever focused on a narrow spot is easy to sell as better.
I just stick with the Imperial unit: Horse-candles
[quote=shane.rrr]Yall see this? I like the idea but fuck thats expensive.
https://www.sinewavecycles.com/products/sinewave-cycles-beacon[/quote]
At first I scoffed at this light but now I am starting to realize its appears to be optimized for cyclists that are doing adventure bikepacking and need a durable dynamo powered symmetrical light for singletrack riding. Bonus is being able to run it off battery (for when puttering along on the trail and not generating enough juice) and charging your navigation tool / battery pack when on the road.
I’d wager that the light is more durable than the Luxos U and probably has better charging circuitry in addition to being potted inside.
But also: ugly as hell and that switch is a terrible idea
Yea what’s the point in a bulletproof light with a switch that you’re gonna break off the first time you wreck
Local adventurebro has just acquired one for the Hunt 1000. I’ll get a report when all is said and done.
They probably should have gone with a rocker switch instead of the toggle
FYI
Merry Sales told me that Kasai is made in the same factory as Shutter Precision. They dropped SP in favor of Kasai, but they didn’t say why.
[quote=kmcdon]IIRC lumens is a measure of how bright the light source is, whereas lux is a measure of how much light actually gets cast onto (object)
Like, lumens doesn’t take into account the beam pattern and lens design, whereas lux does.
(I think.)[/quote]
From the little bit I’ve read, 1 lux=1 lumen per sq meter. So a 100 lux light puts out 100 lumens per meter? That seems like a fuck ton
Lumens correlates fairly directly to number of photons emitted globally (weighted by typical human sensitivity according to wavelength) If you change the lens on your light you aren’t changing lumens.
Lux is the one that the stvzo spec are built around, “how bright is the road lit up” The problem that is that the rating is defined in terms of a light projecting onto a flat plain with the light set at a perfect angle. If you angle your light down the lux goes up because it’s projected on a nearer (so smaller) surface. Two lights can be the same stvzo lux rating but one might put out a lot more light and use it to extend the hotspot further out. Because it depends so much on terrain, lux does do not make a lot of sense if you are shopping for a symmetrical beam MTB light.
Candela is the one that measures “how hot is the hotspot” controlling for distance. If you have a 1 candela light and point it at a surface 1 m away at right angles to the beam, the surface will be lit at the center of the hotspot with 1 lux. More generally lux = candela / distance^2 * sin(incident angle). If you swap for a tighter lens you increase candela while lumens stays constant.
If visible light is like water, then think of a fire engine. Lumens is how fast it pumps water, gallons/sec.
Candela is how intense the spray is, like much water it can spray through a standard-size opening at some standard distance.
Lux is how wet some specific patch of building surface gets, like gal/sec/m^2, depending what you’re aiming at
if you want a wide beam pattern you might pick a candela value that lets you see far enough ahead and then maximize the lumens.
The highest efficiency LED I see on digikey rates 212 lumens/watt. If we take that one then (750 lm @ 3w) corresponds to … 112% combined luminous and optical efficiency. Hmm.
They don’t say with what dynamo, though. It might be possible to tune the power supply to extract more than the nominal 3 W at low speeds like they’re suggesting. Would also mean higher drag, worse mechanical efficiency.
It’s normal to get ~4W out of a modern dyno at a reasonable speed with a reasonably fancy circuit
some Voltage Doubler trickery is possible to get way more, but you absolutely pay for it in resistance and chunky vibration http://pilom.com/BicycleElectronics/DynamoCircuits.htm
[quote=ergott]FYI
Merry Sales told me that Kasai is made in the same factory as Shutter Precision. They dropped SP in favor of Kasai, but they didn’t say why.[/quote]
“Kasai” is yet another fake Merry house brand, not a real company
It would be reasonable that they’re now buying pallets of them whitelabeled from the factory on direct terms (like Supernova or BioLogic/Tern) instead of smaller quantities wholesale through one of the factory agents like before
but there was also rumor of a factory shakeup at SP in the last couple years, so these could be coming off an old production line (notable that the TA hubs are missing from their lineup)
I mean whatevs… but Merry Sales are either lying or being duped.