Since my Nitecore MH25s started discharging quickly (I’m on to Nitecore about it) I started using and old Fenix PD36R that I had for work. I didn’t use it much as I didn’t think I liked it, but on going back to it it’s actually a pretty good light. That being said I do wish it was a little brighter.
I’ve been looking at the newer PD36 models (I like the form factor) and some have much higher max lumen than the PD36R and also have a higher high lumen (1000 vs 800 of the PD36R), however what I’ve noticed when looking at runtimes is that most of these models drop to around 700 lumens after the first few minutes when running in turbo or high (I tend to have mine on high mostly).
So apart from the beam profile is there going to be no difference in all of these different models after the first few minutes when running them in high as they’re all going to be around 700 lumens?
Are there any lights with similar form factor and build quality that run for longer periods (e.g. 2 hours) at a higher lumen, say 1000?
If you want longer runtime you’re going to have to get a light that uses a 21700 cell, and you have to decide whether you want lumens or distance (candela)
I think you’re going to have to switch to what I have, which is a convoy m21f or m21e with either a sft 40 or sft70 or xhp 70.2 or xhp 70.3 LED
If you absolutely have to have a rear tail clicky switch I would recommend a Welltool T12 Plus which can hold around 800 to 1,000 lumens for about an hour I believe my m21f can hold 960 lumens for 1 hour and 50 minutes but it’s not a rear tail clicky switch
Thanks, the newer PD36 models are 21750, but strangely have shorter runtimes in high. I guess this is because high on the original is 800 and on the newer it’s 1000, but as I said they all appear to drop to 700.
I’m not bothered about button position, it’s more size and weight.
In terms of beam profile I like a mix of flood and throw, I like the original PD36R but just with it was a bit brighter as I said.
Related to this, the Convoy M21B with SFT42R is a light to consider. Tail switch, good flood/throw mixture (IMO, some might find it too throwy), high output, good efficiency, 21700.
For more flood and less throw, choose a more floody emitter like LHP531/73B, or a more compact light like S21A/B at the expense of thermally sustainable output.
Don’t fuss over the exact lumen count (800 or 1000), beam profile and throw have much, much more influence on perceived brightness.
For the PD36R form factor but in tail switch, Convoy has S21A, S21B, and S21G; they all produce the same beam, but the S21B will have the best thermal performance due to the integrated shelf.
For an LED to match the existing beam profile (SST40 in the first generation of PD36R), the SFT70 is a great choice. Cranks out 3000lm at the emitter on maximum and has efficient lower modes, at almost the same flood/throw ratio as the PD36R. Choose 5000K for a good balance of output and tint.
Alternatively, you can special-request the SFT42R emitter with 10A driver, which gives you more throw over SFT70.
Thanks. I’ve always used 1lumen.com to check runtimes and this shows that the M21F ramps down to around 750 lumen after a few minutes, is 1lumen not a very good source then?
Ahh, so you’re zeroair are you. I did stumble across your site and I love the reviews, I just couldn’t find a search funtion (maybe I didn’t look hard enough)
I review for 1Lumen and have reviewed a lot of Fenix lights. I do recommend the 21700 lights, either the PD36R, PD36 TAC, PD36 ACE, or the TK series, Tk20R UE, or TK21R (new). The TKs will give you the 800+ Lumen sustained output with long runtimes. The 18650 battery 35 series don’t have the sustained output as the 36 or TK series. They’re smaller though, if that matters.
I’d also consider the Klarus brand. The XT11GT Pro V2 i tested is still one of my favorites.
Testing lights isn’t always consistent due to lots of variables that can’t be accounted for like LED bins, temperature, batteries, etc. 1Lumen tries to maintain outputs that are within 10% of actual, so figure that when considering sustained output.
Yeah I noticed that, but I don’t know how “cooled” affect output and runtime. I assume when it’s cooled it can sustain a higher lumen level for. alonger period of time? This is one of the reasons I tend to compare using 1lumen as I guessed they’d be more consistent. For example, on zeroair the PD36 TAC can sustain over 1000 lumens for 2 hours, but that’s cooled. The same site says the PD36R Pro can ‘only’ sustain around 900 lumen for 75 mins and then it drops to around 700 for 25mins and then to around 300.
1Lumen shows the PD36 TAC and PD36 PRO have pretty similar lumen levels as they both drop to around 800 lumens after a few mintues, although strangely (to me anyway as they use the same battery) the TAC can sustain this for nearly 3 hours whereas the PRO drops to around 300 just after 2 hours.
The TAC actually looks great for me except there’s no battery level indicator, except it will drop to eco when it’s nearly flat. I don’t particularly like you have to remove the battery to charge it but I could live with that, the lack of battery indicator I’m not so sure.
Thanks for the recommendations, I’ll look into them. I have looked at the TK’s but prefer the PD36 series where they’re pretty uniform diameter throughout the length of the light. I might go back and look at them though if they can withold higher lumen levels.
For the record, these newer PD and TK lights don’t have active thermal regulation (like Anduril) that I know of. It’s all timed stepdowns with a thermal limit so air cooling has little impact on output. The early PDs like the PD35R V3 and i think the PD32 had active thermal management which wasn’t great.
This is a good point to bring up: compactness and sustainability are conflicting objectives (the latter requires a lot of mass and surface area), so OP must find an optimal balance between the two.
Unless you are ok with the light becoming very hot, it is not possible to have a very compact light that also sustains high output.
