That is the point in lux, demonstrating the light intensity in a small area. Halving it for comparison with other lights like Ladelux is not justifiable. Several websites have copied those figures/graphs (i.e cyclingabout) and I've had several people ask by email by the C1 lux "is so low?". For the C1 the emitters (which is on/off or levels) have no relation to power-draw at the hub (C1 differs from Ladelux here, C1 can sink any wattage any dynamo can provide and Ladelux with the li-ion is limited to about 1A, so 4W roughly) and Andreas knows this from the previous discussions I had with him. There is literally no justification, sorry.

The main issue with the results is that they aren't sampled. Phototransistor/diodes are much faster than tricks used in dynamo (and battery for that matter) lights to appear brighter and won't catch them, like low frequency 25/75 duty PWM which briefly lights up the area and then your brain fills in the rest but to the detriment of eye strain. Sampling catches other issues like throttling where heat build up then lowers performance. Throttling is mainly due to LED temperature or buck/boost chips. Sampling over time is very important.

The market for dynamo has radically changed in 10 years whereby the lower-end more casual sector has been replaced by USB power-banks. Now dynamo is primarily for auxax racing/events where conditions/requirements tend to be more extreme. Here's a C1 on the Fat Viking event in Norway (currently in-progress). The photo was taken at -30C. instagram.com/p/DT-6ZVSjs7w

StVZO for C1 will likely come eventually but I can't say whether the main beam will become a high one. There are pro's and con's. As you correctly say the C1 lights up everything with a cut off, it's very wide and with minimal hotspots making it able for technical riding (or avoiding potholes!). I don't know if sacrificing some of this is worth it but no right or wrong answer here. If a rider really needs a longer throw without cut off an option is to buy a cheap rechargeable bike light which does it (like £20 there are so many) and connect it to the C1's #2 USB port. After the device in #1 USB is charged it will then top up the bike light for use at night.

I get that using the SON28 Classic keeps consistency but at some point it's time to move on. That point surely came when nobody was buying the SON28 Classic anymore?

The point with the lux is purely due to german regulations. The requirements state that 4° to the left and right of the brightest spot and 1,5° below the brightest spot the manufacturer has to ensure at least half of the max lux value. (This equals an rectangular area against a wall in 10 m distance of 26 cm height and 140 cm length. German regulations do not care about lumens. A light can have as many lumens as possible as long as it meets the lux requirements. Here they are, in german, on Olaf Schultz webpage: TAÂ 23 Scheinwerfer für Fahrräder. There are no other reasons than german regulations, and this is why lux values are only given for StVZO bike lights

Then the authors of those article obviously had no clue about lux and lumens and/or did not properly explain this to their readers. Probably they did not translate/read the german article properly before using the information from fahrradzukunft. That is not the fault of the authors of the original article.
Lets discuss the results at 30 kph exemplarily: the IQ-XL has 230 lx/428 lm in low beam and 190 lx/614 lm in high beam. The C1 has 80 lux/ 575 lm. From these values, one cannot say which of the two lights is better. They are just different in beam characteristics.

If you want another test of your light present in the german web, with probably a bit more reach, you could sent the C1 to fahrradbeleuchtung-info.de (there is a youtube channel as well, i provided four of my lights (3x Lupine, 1x Litemove) for testing to the nice guy operating the site). The focus there is probably more towards light and less towards charging. Lux and lumens are measured as well.

Why do you not publish a max lux value on your website if this is important to you? you could also add a section about lux and lumens on your homepage, saving you probably a few emails with "why is your light so dark". You could also link to this test, which explains it pretty nicely: https://www.pinkbike.com/news/10-bes...den-rated.html

So this is one of the probably 100 customers worldwide who have a need for continous power at -30C. I admire the people who do those races at those conditions, and i think they are (positively) crazy... As much as i'd wish to have we have more people using the bike in the winter for transport, this is in my experience a vain hope, especially for long distance trips.

i agree with you, but i did not spend my time on those measurements. Until someone else does this comparative measurements as well, one has to be thankful for the unpaid work of the authors. i would have found it nice if all of the equipment would have been tested with a newer SON28 and not only a few (Ladelux, M99 Dy pro, K-Werk). I personally would have been very interested in the measurement of the IQ-XL with a current SON28, a better shimano hub or the new SON29...

Note how you have quoted the C1 as 80 lux when it is 160 lux (according to Schultz measurements). When both beams are forced on the main beam is 50% in lumens. :crash:

The C1 emitters top out at about 4V/2A, so 8W. Depending on the dynamo and wheel size this will come somewhere around 25km/h. After this the C1 can't get any brighter but it's still able to sink excess power. When Schultz tests these lights he simply sets the speed and takes a single read. I already mentioned one aspect which is throttling but I'll mention another very important one which lack of sampling means isn't covered - power factor.

Regarding Andreas values, they are not logically plausible. You will notice that in his results the Ladelux beats Igaro C1 and Forumslader at USB at lower speeds. All three use MPPT, Igaro/Ladelux at least have active rectification (doesn't give much few % at best) but the largest factor or extraction performance is reactance compensation (+25%), which Ladelux doesn't have. Without independent testing I simply don't believe the values to be true. Within the resonant frequency ranges both C1 and Forumslader should extract significantly more power. In terms of these frequency ranges C1 has two stage switching with dynamic capacitance and targets 10-30km/h optimally. Forumslader (iirc) has four stage switching with fixed capacitance and probably enhances the same if not an even greater range.

I am very sorry to disappoint you, but nowhere on Olaf Schultz website are 160 lux reported for the Igaro C1, not even at 8W.

86 lux are reported for the main beam at >8W, 55 lux at both LEDs and 8W.

https://cimg5.ibsrv.net/gimg/bikefor...f030c76e3b.png

So previously the lux was specified on Andreas article @ https://fahrradzukunft.de/40/steckdose-unterwegs-10

However I've checked and now it's not there, or I'm going blind. It was this I thought you were referring to.

I've not seen Schultz's results but they were meaningless for the C1 back then as sampling was required.

Also it's not possible to measure the input wattage for the Igaro C1, Forumslader or any device using reactance compensation. Doing so requires internal access to measure after capacitance is added. I have mentioned this before - apparent & real power. https://www.allaboutcircuits.com/tex...pparent-power/

it still is, in fig 33. And it are the same values which Olaf schultz presents on his website. What a surprise, since it is mentioned in the article that Schultz did the lux and lumen measurements... Admittedly i did not check the values on Schultz website previously, i did this just shortly before writing my last reply (it is not really designed for mobile devices and a big screen is definitely useful)

Do me a favor and tell me the lux value that you measured with the proper method. Since at least 2 or 3 posts you are avoiding to mention this or i missunderstand your posts. Did you measure 160 lux as max lux value with suitable equipment? Why is this not stated on your website? Also please keep in mind, StVZO requires lux measurements in 10 m distance.

Doesn't matter. Schultz powered the Igaro with a SON - most probably the older version as well - at 225 rpm (equals 30 kph), as stated on his webpage. According to your earlier post, this should be fast enough to ensure maximum light output of the C1.


Let's rephrase it: without testing according to your specs you don't believe the values. That is ok. That you again insinuate that the authors intentionally put your igaro in a bad light is not helping your case at all.
That being said, i know of three sources for these kind of tests: a guy who writes in kyrillic letters and whose tests are translated by cyclingabout (e.g. https://www.cyclingabout.com/best-dy...g-bikepacking/), Stefan from fahrradbeleuchtung-info.de and Andreas Öhler with Olaf Schultz.
Should you find a service provider who could do the testing according to your wishes and specs, please present your test plan, the power sources (i.e. hubs) you intend to use and the lights/chargers you want to test. If it is a nice plan, i'll add a bit of my money to your test campaign, which will probably cost at least 5000 EUR/GBP/USD..

Lux hasn't been tested @here (I never said it had), but it's not of great importance, even among Stvzo certified lights it is relatively meaningless in terms of beam quality.

Lumens we know from the testing routine Schultz used are not going to be reliable for the reasons I specified. Your next question will be to do it ourselves, which is already in-progress. A 40cm aluminium sphere lands next week, the three sensors are ready and the test-rig will sample at over 3KHz for various programs (hills, stop/start, fixed speed etc). So we shall see.

I have stated several times why measuring wattage at the hub can not be done with Igaro C1/Forumslader.

Moving on this might be of interest. SON Edelux does 100lux @20km/h. At this speed Igaro C1 can extract about 5W after losses, or 5/8 of it's maximum brightness. Schultz says the max lux is 86.7lux, so 54lux @ 20km/h. This is very rough calculation of course, but there's a couple videos on youtube which show the C1 against Edelux at about that sort of speed here. youtube.com / watch?v=mwZT_W7R7DU

So Igaro C1 should have just over half the throw of Edelux. Here's two screenshots I took from the videos at the same point with the fence to the side.


https://cimg9.ibsrv.net/gimg/bikefor...f0b0ad0b03.jpg
SON Edelux
https://cimg0.ibsrv.net/gimg/bikefor...4b8b684b48.jpg
Igaro C1

You complain at great length that the lux values given in Fahrradzukunft are wrong, but you never measured it yourself. How do you now it is wrong when you never measured? I wrote the same that it is not of great importance, but you kept complaining. And as you didn't measure it, you take a video as proof that the measurements in fahrradzukunft are wrong? This is just getting totally ridicolous.

[QUOTE=igarocom;23689470]
I have stated several times why measuring wattage at the hub can not be done with Igaro C1/Forumslader.
[/qote]
I cannot believe this. Please state why. I read a bit on active and reactive power. The active power can be measured and is the energy which is used by the device (C1,Forumslader etc). If you managed to reduce the reactive power, it is not relevant for the energy usable by the device. If you managed to transform reactive power to active power, then it can be used by the device and measured. Furthermore, the device used by Schultz and Schmidt is able to measure active, reactive and apparent power. I simple google search with the device name, which is given in the text, would have told you this. So your argument is pretty weak...


Let's see what you measure. However Schultz had access to an professional ullbricht sphere and unless you show validation/calibration measurements for your sphere/test setup, i tend to trust the values from Schultz more...


As a wrote above using a video to proof that the lux values are incorrect cannot be taken serious: a)it is an action cam with a limited dynamic range b) we do not have speed readings c) it is hard to pick the same location. The spot you picked in the video is in my opinion clear cherry picking: Ladelux and Edelux (and the B&M Cyo Premium) have a relatively small spot, where the highest lux value is thrown (i use a cyo premium myself). The area with the maximum brightness of the C1 is reasonably bigger compared to the B&M reflector throw. The brightest spot of the Edelux is most likely going through the holes of the fence or above the fence into the darkness. You should have picked the part where he drives through the forest.

The videos are good to get an idea of the light characteristics and the guy did his job well, as he fixed the camera settings and specified them. From the way the guy is adjusting his lights, Edelux is the wrong lamp and the light distribution of the C1 is more usable. For riding on bike paths and roads, Edelux is better suited, when aligned as intended by the design of the reflector (i.e. the cut-off should hit the surface in 30to70 m distance, depending on the riders preferences)

"I cannot believe this."

That's OK, you can believe what you want, even when told by an electronic engineer. ;)

The figures and test method do not use sampling therefore have no means to average out over change in throttling (storage, LED heat), power-factor, temperature change. Devices are treated like a resistor but they don't behave like one over a period of time - not at all.

Fact.

Real power for those devices which use reactance compensation can only be read after phase correction. It is also a fact that Andreas didn't have access to it and neither did Schultz, so the 8W or any value quoted for Igaro C1 extraction wattage is not correct. Same for Forumslader unless he went into the PCB to find the correct point. This is not possible for C1, it's encased in epoxy.

Fact.

MPPT is an impedance value which extracts the most power. Impedance is L,C,R. When C is added in phase correction the impedance changes and so an adjustment is necessary. Being L is fixed, that correction comes by lowering R.

This is what Andreas is measuring. In simple terms he's measuring real power in the wrong point of the circuit. Because both Forumslader & Igaro C1 have lowered R, his reads are less. Then he compares these reads to Ladelux.

Fact.

Some reading for you:

1. Thevenin's Theorem
2. Power factor (distortion & displacement)
3. Impedance

At this point I'm exiting the discussion, there is no point fighting someone who is given reasoning but then states they can't believe it.

You can continue to entrust Schultz & Andreas for your information but as stated:

Schultz doesn't have equipment to sample over time, still he's operating in 'halagon bulb' test mode.

Fact.

Andreas does not understand (1,2,3) and attempts to assist pre-publish of his article were in vain.

Fact.

I wish you good the best exploring and learning.

// exit

I imagine the guy positioned the lights as so they best illuminated his way forward. I'm not going to automatically assume he didn't. By my eyeballs, which aren't his, they're both set to do that.

Now you've attempted to claim bias again so let me respond to that. I 'anti-cherry' picked to be as fair as I could, but it's not possible. I didn't use the forest video as it's so short and both C1/Edelux are starting or close to 'dead' in both videos (he says in the description). C1 is putting power into it's very large super-capacitors so is dim and the forest video isn't long enough. Edelux has a tiny super-capacitor and reaches full brightness almost immediately. It's the same for the path video it's not long enough, but it's longer so better and it's why I chose a point later on in that video. It would have been nice to see what the Igaro C1 was like after 10 minutes. To compare light output equally at a point of time both devices shouldn't be putting in or out any power into storage. Since this isn't true of the C1 for these limited length videos any screenshots of comparing the C1 to Edelux puts C1 at a disadvantage. I am guilty, but I did it anyway, because even disadvantaged the C1 obliterates it.

This is a good example of why sampling over time is so important.

Now I really am exiting.