This is the second review of this series of four Streamlight lights (Sidewinder, PolyTac 90, Nitecom UV and Sidewinder Compact II) and up next is the PolyTac 90 which has actually been around since 2010.
Aimed primarily at rescue services, this tough right-angle format light may prove itself to have more general appeal.
Available in black yellow and orange, and with or without the Gear Keeper retractable lanyard.
First impressions are a little contrary. Being made of a nylon polymer, the PolyTac 90 is very light weight which seems in conflict with the serious look of the PolyTac with its professional details such as the folding metal karabiner and removable/adjustable steel clip for fixing to turnout gear
Whether intended or not, to me the PolyTac 90 is reminiscent of a fire hydrant, which is of course very appropriate.
What is in the box:
The PolyTac 90 comes in the blister-pack type of packaging.
It is supplied with instructions, two Streamlight CR123 batteries and the Gear Keeper retractable lanyard.
Taking a closer look and looking inside:
Looking round the PolyTac 90 shows the key features, of the right-angle head with good sized textured reflector, the removable steel clip, and folding metal karabiner (show open and folded).
Looking more closely at the LED, the emitter is Streamlight’s C4 emitter (though C4 seems to cover many different LEDs).
The tailcap is flat bottomed, allowing tail-standing and being of plastic construction, the spring is shaped to make contact with the body tube contact and the negative cell terminal.
The threads are of course also plastic, but seem well formed. I’m not sure about long term durability.
The end of the battery tube has a metal contact ring.
Looking further inside the positive terminal is a flat metal strip.
Modes and User Interface:
The PolyTac 90 keeps things simple. There are three modes, High, Strobe and Low.
Using the soft click button on the top, one click turns it on to High, a second click turns it off. So used like this there is a single mode on and off.
Double clicking the button and the PolyTac 90 enters a Strobe mode at full brightness.
Triple clicking the button gives Low.
That is all there is to it, and I suspect users of this light will mainly use it on High.
Batteries and output:
Streamlight specify only CR123 can be used. However after querying this with their engineering team, the circuit designer said it ‘should’ be able to handle RCR123.
Tests were carried out with two CR123s, two AW RCR123 cells and a single AW IMR cell with a dummy spacer.
To measure actual output, I built an integrating sphere. The sensor is a photo-diode restricted to visible light only (so Infra-Red and Ultra-Violet will not register). This was chosen as our eyes can only use the visible wavelengths of light so this is generally the only useful output. The integrating sphere was calibrated using 12 different reference sources and taking an average of the factor used to convert the measured voltage output to Lumens. Output figures are quoted as ANSI lumens where the measurement is made 30s after turning on the specified output level. Initial figures when first switching on are always higher, but all quoted measurements are ANSI.
Please note, all quoted lumen figures are from a DIY integrating sphere, and although every effort is made to give as accurate a result as possible, they should be taken as an estimate only. The results can be used to compare outputs in this review and others I have published.
Streamlight – PolyTac 90 I.S. measured ANSI output Lumens PWM frequency (Hz) High 154 N/A Low 15 138
Output is regulated and as the batteries become depleted, the output remains pretty consistent, until it falls out of regulation when the cells are almost depleted.
Now, there were some interesting differences when using the three different cell configurations. The difference was not in the output. The circuit’s regulation handled the 4.12V, 6V, and 8.4V without changing output, however…
Being a soft click button, there is parasitic drain to be considered as the internal circuit is kept powered. The parasitic drain of the PolyTac 90 appears to be related to the input voltage.
Using CR123s (the recommended cells) the parasitic drain was 0.18mA.
This equates to fully depleted cells after just under a year (347 days)
Using RCR123s the parasitic drain was 43mA.
This equates to fully depleted cells after just 17 hours. However after monitoring the cell voltage and the drain, as the cell voltage started to drop, so did the parasitic drain.
This led me to try the PolyTac 90 with a single RCR123 and a spacer (more details in the Night Com UV review to follow). I used an AW IMR cell to ensure it could deliver the required current.
With this cell, the parasitic drain was 0.16mA which means 195 days to empty the cell.
The result of all of this is that regular users can use RCR123s, but will need to recharge them regularly to keep it always ready, and in fact it will be more reliable if only a single cell is used.
For CR123 users, if it is used regularly there will be no problem, but this light cannot be left on standby for long periods, as the parasitic drain is high.
In The Lab
In an attempt to quantify the actual beam profile I developed the following test. There are probably many flaws in my method, but it is simple and easy to carry out and seems to provide a good enough comparison.
The method used was to support the light 1m off the floor and 1m from a wall, with a tape measure on the wall. The zero of the scale is placed in the centre of the hotspot and a lux meter is then positioned at points along the scale, with the measurements recorded. Beam shots are often taken with the light shining on a flat white wall, so this method is simply measuring the actual intensity across the beam on a flat surface, not the spherical light emission.
The results are then plotted on a graph.
For the best throw you want to see a sharp peak with less of the distracting spill. For the best flood light the trace should be pretty flat.
The PolyTac 90 beam profile is shown here compared to the other Streamlight lights I have on review. It has sharp peak which drops very smoothly as you move out into the narrow spill area, giving it a piercing beam excellent for cutting through smoke or fog or giving good throw.
Taking this a little further, I calculated an approximate factor to apply to the lux measurements, as each measurement gets further from the centre of the beam, it corresponds to a larger area onto which the light is falling. It seems to me that this should also be taken into consideration, so I applied these area corrections and came up with this odd looking graph.
The key quantity here is the area under the graph line. This should correspond to the total light output.
There is also a reasonable amount of spill light, making the PolyTac 90’s beam useful, but without creating spill-blindness (the effect of particles in the air reflecting the spill light back and obscuring the target).
As shown by the previous beam profile graphs, the PolyTac has good throw and smooth narrow spill.
The beamshot is exposed to give an impression of the beam’s brightness to the naked eye.
Of the four Streamlights on test, the PolyTac 90 has the most refined beam helped by the textured, well shaped, reflector.
What it is really like to use…
The soft-click switch requires quite a firm press to operate it. As it is not recessed this helps avoid accidental switching on. For the double and triple clicks you need to get your finger lined up and need to complete the sequence quite quickly.
The maximum output is appears brighter than its 154lm would suggest. This is mainly due to the narrow spill and well focussed beam. It actually is a bit over bright in normal indoor use, but would be good in poor visibility conditions.
The low level is a more suitable level for general use, it is just a pity you need a triple click to get to it.
Though not terribly stable as it is a bit top heavy, the PolyTac 90 comfortably tailstands, but the strength of this light is in its variety of attachment options. The clip can be adjusted (though be warned it is difficult to remove and very difficult to reattach) and the folding karabiner easy to clip on and remove. The Gear Keeper works well, but leaves the light swinging around a bit too much.
The clip keeps the PolyTac 90 firmly attached to turnout gear or MOLLE attachments.
In all, the PolyTac 90 has been thoughtfully designed. The basic form provides the right-angle head design ideal for attaching to clothing or load carriers with a battery tube configuration making it comfortable to hold by hand. The range of robust attachment options make this attractive to users who need to clip on a light and be confident it will still be attached when they reach for it.
The last image provides me with a link to the next of my series of Streamlight reviews, the NightCom UV – coming to a CPF thread near you soon.
Here the PolyTac90 is photographed illuminated by the NightCom’s UV leds.
Test sample provided for review by Streamlight.
I’ll update post 2 of this thread once I have some more comments to add....