Hey Barkuti, no problem, it’s always good to hear your 2 cents.
Don’t know, maybe warm white is better. Maybe red… :nerd_face:
I’ve decided to start with yellow since I remember some cars use yellow anti-fog lights. Warm white is typical for old-fashioned bulb lights and for some reason somebody decided yellow will suit better.
But it may also be some other color/wavelength is better (e.g. green or red) but not commonly used due to interference with colors meaning.
Well, first I’m gonna build the light, then we’ll see if any difference can be spotted.
Looking forward for the 4*18A with SBT90 !
Simon confirmed several times there won’t be 4x18 but 3x21 instead
I would be happy with that as well 
My wallet won’t, since i need to buy three new (matching) cells which i need to hold together.
Plenty of 18650’s though
Wouldn’t it be possible to use 3 pcs 21700 -> 18650 adaptors? Need only to make the springs somewhat tighter, to also hold unprotected 18650 in place.
There will be two versions
3*21700 with SBT90.2 and 4*18650 with SBT90.2
Nice
Simon (and the others)...
Will the 4x18650 version require to use button top batteries? If so, I will look forward even more to seeing the 3x21700 version.
Why? Because a) button top batteries are harder to get and b) button top batteries often add significantly more contact resistance, especially those with cheap joint-welded buttons that tend to rust quickly.
My hopes are that these new lights have a different battery compartment with brass buttons on the positive poles of the head unit instead of a brass ring (which requires buttons on the batteries).
Will the 21700 version work with unprotected Samsung BT 18650 30Q’s, using battery adaptors? Or will the 30Q’s be too short?
I think Simon uses this adapter for flat top batteries:
Awesome Simon! Other companies could take example from your thorough designs
Amazing! I don’t know if it could get any better.
18650batterystore.com you can get (3) 40t plus shipping for about $20 (US). But i know what you mean.
Hello Simon,
In this listing:
https://www.aliexpress.com/item/1005001683334790.html
You mention, that driver has 4.8A current, but for this CSLMN1 specific tint (.FY), only between 2.5-3A is recommended. Above 3A, output flats out, and at ~5A, output is even less, than at ~3A - this means, efficiency drops very fast.
Look at datasheet: https://dammedia.osram.info/media/resource/hires/osram-dam-15011579/KY%20CSLNM1.FY_EN.pdf
I would strongly recommend replacing the driver to 8×7135 driver (~2.8A).
I think all the yellow CSLMN1 variant has the same specs as the white variant in paper. The white version output peaks at 4.5A-5.0A according to a test and 5.75A according to another.
I can’t find any test for the yellow variant, do you have one? The datasheet only shows data for up to 3A as for the white version.
Ok, now I reveal the “super secret”.
I have the Noctigon K1 fitted with the specific variant, CSLMN1.FY, and my K1 has even less output at 5A, than around 3A. So you can trust me.
Also, you should look for CSLMN1 specifications for other tints, and you will need to compare If (forward current) vs. lumen output graph carefully for each of them, and then, you will see, that for the Yellow and the True Green variant, output starts to flat out much sooner, than for other variants. Also, those graphs are probably for a close-to-perfect soldering work, which will usually not happen. So, for less-than-ideal situations, that output will flat out even sooner - this is why we need to examine each kind of emitters (or at least make use of the graphs as well in the specification, no just the basic stats), and choose safe driving current accordingly.
Hank stated to me the K1 drivers are not being tweaked per LED type (at least the white W1 is the same as the green W1), so this is not surprising. Each of these color specific W1's have their own output curve with a different peak current, and Hanks and Simon are not properly configuring their drivers accordingly. Of course the other variant is the quality of the LED reflow, also assuming it's on a known good 3030 MCPCB of course.
At least with the K1 you can swap a resistor to control the amp output - maybe can do the same with Simon's driver.
Emitter technical name is CSLNM1, not CSLMN1 fellows.
Concerning driving current, as you approach peak output the gains with the increase in current get smaller and smaller, until they dissapear or even turn into losses. Thus, with all the above variables given it is wise to settle for a 75 or 80% of the peak output driving current, that way above 90% of the peak output is still attained and emitter stress reduces considerably.
I would expect that it may not be financially viable to tweak the driver for each of these emitter variations.
Oops, technically my typo dragged the responding folks as well.
Yes, for this reason, I always prefer to keep a safe margin from the peak output.