Be aware, possible visual occlusion open emitter optics.

[zcap]

Good post @zcap. My most recent problem (see above) was from a drop of water covering the emitter, not the lens. Recoil didn’t work to clear it. I wonder if a hydrophobic coating would help.

To clarify, I also coat the emitter lens with wax treatment as well. In addition to filling the main body with water, I submerged the lenses in water as well, but most of the water immediately runs off when I level the pistol due to the coating.

Here is the same test with an SRO. As I mentioned earlier in the thread, the SRO performance in water does not match the RMR. This is sort an extreme test since I use tape to purposely prevent drainage and fill the SRO to the max possible level, but under these extreme conditions the SRO dot is not usable. However, as soon some of the water drains the dot returns with usable clarity.


1. SRO with lens treatment, drain holes taped, filled to overflow with water.



2. Sight picture of SRO with lens treatment, drain holes taped, filled with water. The dot SHOULD BE right above the front sight, but instead a faint ghost dot appears much higher in the window.



3. Sight picture of SRO with lens treatment after most of the water draining (should happen quickly if the drain holes aren't taped). The dot is now in the correct position, and has minimal dot dispersion.

[zcap]

What brand lens treatment are folks using?

In my experience most wax or paste products work well, but liquid products don't leave enough hydrophobic film to be effective. EK Products makes a wax product that works well and is widely available. However, as I have posted, some open emitter dots are much more susceptible to water than others, so you'll want to test your chosen dot with whatever coating you choose.

[Erick Gelhaus]

Interesting. Have seen enough issues with openly carried, open emitters, though this is a new one. I'll keep an eye out the rest of winter & into spring.

It does that winter has been paused, at the least, in my area. Sad, i was looking forward to trying to stuff out.

[zcap]

Related to the OP, here is how a hydrophobic wax treatment affects fogging on both open and enclosed emitter optics:

RMR completely untreated (left) and RMR with wax treatment on emitter window and both sides of lense (right), 57 degree fahrenheit ambient temperature



RMR completely untreated (left) and RMR with wax treatment on emitter window and both sides of lense (right), immediately after breathing on both units (untreated unit dot completely disappears)




enclosed emitter, untreated lenses, 57 degree fahrenheit ambient temperature



enclosed emitter, untreated lenses, immediately after breathing on lenses (dot is fainter but still visible, sight becomes occluded)



closed emitter, both lenses treated, immediately after breathing on lenses (dot maintains brightness, sight is mostly unclouded)