I did not say all that working day 6-8 hours in turbo. But maybe 5 to 10 times a day I need to see what is happening exactly , be on guard and run the H1 for 10-20 minutes. Works fine with Olight H2R and even better with Armytek Wizard Pro - not with that fluctuating light of ZL H600Fc MkIV.
If it works for you - great - enjoy it.
None of my last-generation Zebralights look anything like that. The only one with any significant oscillations in normal use is the H600Fc III, which has a few while it stabilizes the output (rock solid for over 200 minutes afterwards). The first time I ever encountered that kind of PID ringing was the SC600w HI IV and SC64c. It would appear ZL started dicking around with the PID tuning mid-production in some previous generation lights and applied the changes to all latest generation lights.
None of MKIII lights have any oscillations like the MKIV’s. You must have got one with an issue or something. I have two different H600 MKIII lights and they both have perfectly smooth regulated outputs once stabilized on H1. Here is my H600Fc MKIII on H1 with no cooling(ambient temperature 23.8C)….
The graph was recorded with my Extech HD450 Datalogging light meter with the resolution set at 1 second intervals.
H600w mk III with XHP35 is slightly different from H600Fc MKIII (xm-l2 easy white).
may be, 1st series of MKIII has old version of thermocontrol,
late series of MKIII - new version.
I just returned my H600fd mk4 for a refund. The oscillation was really viably annoying. Will wait for a newer version with better PID. I have several other Zebralights that are flawless. I know they can do better.
Just briefly tested one H600Fc Mk4 sample, thanks Kaybi.
Just like on most frosted ZL’s, output is quite far from specified (1124 lumens measured @30s vs. 1568 advertised). The tint is great with little difference between modes. Tint shift is a non issue thanks to the diffused lens. Efficacy is mediocre.
CRI and tint data measured from the hotspot on max mode (H1). Very nice tint (duv 0.0011) at 3983 K.
CRI data on M1. Slightly warmer and farther away from BBL but still great (duv 0.0021).
Total system efficacy over the runtime is 86 lm/W (retested the battery) 89 lm/W measured on the 410 lumen H2 mode. A clear improvement over the H600Fd Mk3 with an XM-L2 Easywhite which clocked in at 67 lm/W especially considering the CRI90+ emitter on the Mk4. Still far away from the H2R (135 lm/W).
And here’s the PID oscillations on H2 when it’s not cooled with a fan.
Whole runtime
Zoomed in to the first hour
Looks like they need to fiddle with the PID a bit. I’ve never noticed oscillations on my Mk3 so either they weren’t as pronounced on that model or it’s just too hard to see with naked eye.
That must be an early specimen (pre-ordered or bought fairly soon after the release of the Mk. IV series). These early models had this overswinging or pumping issue (the PID regulation was not adjusted properly). Zebralight has since fixed this issue, newer lights are, as you would expect, regulated perfectly without oscillations.
I just tested my H600FC MK4 (mine was a pre-order unit) on the 560 output mode up to 30 minutes. I’m not going to deny that there isn’t some form of PID on this output, but if there were any changes I saw, they were small enough to make me throw them off as placebo. It was a relatively smooth output. I could not detect the oscillation, or at the very least, nothing was glaringly obvious and distracting.
I was planing to buy a ZL with modern emitter but after seeing all these fluctuation issues I think I’m ordering a XML2 version instead, butter smooth PID if I remember correctly from my old H600.
It’s almost impossible to see the 1 oscillation per minute with a naked eye.
will34 have a look at my post two above yours. Zebralight has long fixed this issue. My pre-ordered (November last year) SC64c has some oscillations, but my SC64w that I bought at the beginning of April has butter smooth regulation.
Maybe so, but running the light in it’s lowest setting gives a very visible flicker. And that’s not just on white walls.
If that’s true than I don’t see any big issue. The PID was meant to output as much lumens at any given time while keeping the light’s temperature safe, so oscillation is going to be a given, but as long as it’s impossible or almost impossible to see.
That’s not what I was trying to say. This discussion is for a large part about PID causing variations in output. It’s also mentioned that may just be a firmware error that will be fixed in later versions.
What I’m trying to say is that there are other issues with stable output too.
When I switch the light to low which is 3.4 lumen without PID control, the light flickers very visible like a fast strobe.
Maukka, have you tried measuring the parasitic drain of the H600Fc Mk IV? I measured the drain of my H600Fc but I am not sure if what I got was correct (around 1700uA using a Uni-T UT120C dmm connected in series at the tail end of the light).
No, didn’t test that and I’ve already returned the light to its owner.
Andrey, maybe you could measure the standby drain of your H600Fc if you still have it :-). Thanks.
I can measure this, but I have simple multimeter and it can’t measure less than 0.01mA.