Hello all,
I have an Astrolux S1 with 18350 tube and battery.
Will I get more (short term) lux (brightness) with a 18650 tube and battery?
I would think the answer is “no” since the only difference is capacity (how LONG I get more brightness) but since the voltage and short term amperage are the same, the LUX with a fully charged battery should be the same.
Correct? False?
Please comment / explain so I can decide whether I should get the 18650 tube or not
Thank you
I don’t know if the S1 is a Regulated driver or a FET driver, but:
For lights that have low resistances (bypassed springs) and FET drivers, the type of cell makes a significant difference. (Most) 18650s are capable of flowing a lot more current than 18350s.
Look at the discharge curve on HJK comparator for a good 18650 and a good 18350:
Don’t look at the capacity, look at the way the voltage sags at higher amp draws.
If the light is regulated and draws less amperage than is enough to burden the 18350, then the two batteries would be equal brightness.
If the light is regulated and draws enough amperage that it is above the threshold to burden the 18350, then the 18650 battery would be brighter because it can supply more current.
I have both blf a6 and astrolux s1 (each has a different tint) and I have both tube lengths. After I bypassed the springs both of those lights performed a good deal brighter on turbo with 18650 batteries. In my case, I use Samsung 30q’s from mountain electronics. If you are running on the lower levels only it really won’t be very noticeable except, of course, with run times. I hope that helps. By the way I absolutely love these lights
Thank you to both of you! I will order now the 18650 tube and I will do the spring bypass mod.
I am impressed even with the 18350 cell - I am looking forward to see how it will work with the 18650 
It is hard to beat the quality and power of thaws lights especially for the price and small size. The S1 was one of the first high quality flashlights I purchased and probably the first step on my flashlight addiction. Be careful yourself, this light won’t be your last!
I know… Also got very recently a Fenix FD41 and 3 more (Convoy C8 etc) in the mail from Gearbest. Cool things
Started with nothing (other than a few really cheap ebay zoomies) a few weeks ago. Got the S1 first - but had no battery for it until recently. So while waiting for the battery did some research (I learned a LOT here) and bought a few more flashlights
Now I have the battery and I showed the S1 with 18350 to a few people: they were all amazed and want to buy one too
Ordered today the 18650 tube on ebay…
Yeah, this place is fantastic. Check out some of the battery and charger testing pages. I always check them before I buy anything battery related. There are some talented contributors here.
That’s for sure! Tons of great info for a newbie like me.