Uniquefire UF-1405 - A worthy zoomy?

About the glass replacement lenses talked about. I have gone through quite my share of lenses from Fasttech, Edmund, Anchor, Thor, and Alibaba acrylic mass-produced lenses for common zoomies.

What I have found is what you might expect, you generally get what you pay for, of course. However, I obtained a few very good looking lenses from FT, which under inspection did not present many imperfections, ripples, or bubbles in the glass at all. Yet what I was usually most surprised to find, was that when I would obtain a cheapie glass lens like that, that also met the same objective-aperture size as an acrylic lens, the acrylic lens yielded higher kCd by a substantial percentage in nearly all tests. For example, a very cheap host I have available here locally on the store shelves is a sliding zoomie, with 50mm plano-convex acrylic lens size (total lens OD). When I replaced that lens with a FT 49.5mm lens (JGF-50DT-2 49.5mm Optical Glass Plano-convex Lens), having the same lens aperture (curved diameter) as the acrylic lens, slightly shorter FL by a few mm, the acrylic lens yielded a kCd over 25% greater. What I have found with acrylic lenses, is it is really hit and miss—some have visible wavy dimples on the plano side, or fuzz-like strands inside the plastic with bubbles galore. But, when both lenses are “great” looking, I almost always find acrylic to be better in un-coated transmittance than cheap glass. I would likely attribute this to the acrylic having a lower index of refraction than some of the cheap glass used by these cheap lens makers. Furthermore, there aren’t many options when you do find a size you want, so that doesn’t help things. It is well documented however, that acrylic yields high-performing lenses in many different applications for commercial component use over some or many glass substrates. So never, ever, dismiss acrylic!

When the glass is quite good however, the focal image is very smooth to sharp all around the area of optimal focal-point, with very limited coma even if slightly de-focused. When the lens has a poorly calculated mold/aspheric profile, or poor glass substrate (while still looking geometrically optimal in casting), at nearer 10-15 meter distances the image will be filled with visible coma from many stray light-ray refractions radiating from different non-collimated angles. That is your dead giveaway to a cheap glass substrate; a fog of light around the focused image.

Edmunds and Thor have provided me excellent glass I will say. I do use an optical translation stage when testing lenses (twin moving stages adjustable on a fixed 500mm rail through rack-pinion knob adjustments), so that near perfect alignment/FL does occur in the tests. I have a coating supplier for AR-VIS broadband now, with a new coating available that covers the entire range of LED white light mix from 425nm-675nm @ <0.5% R value with zero R rise between those wavelengths. Such coatings will further benefit the kCd by typically 5-6% minimal increase, sometimes as high as 10%, and result in very true color rendering of the die. …Makes me giggle when I see FT stating; “98% Light Transmittance” on un-coated lenses. :slight_smile:

I am going to pursue one of these light builds with one of my reflective apertures and follow the progress here. They do look like very interesting material for an overhaul. :slight_smile:

please stop spamming!

Quit spamming BLF!

@MEM, thanks very good info as always :slight_smile:
I look forward to see what you can do with the UF-1405/1504 platform :wink:

I have only very limited experience with similar sized glass vs acrylic lenses, but thanks for confirming my suspicions and explaining what to look for, very useful. One those few tests i have done i have also found the stock acrylic surprisingly to me be superior, because then i didn’t realize that just because it’s glass doesn’t mean it is superior.

Can you tell me where to buy some good quality cheap acrylic lenses? preferably in this size for the 1405/1504. Or is it just to search alibaba/aliexpress and hope you find & get a good one.

This coating supplier you are referring to, how much does it cost and where can we send lenses to get upgraded with good quality AR?

Thanks for the infirmation, MEM. I have a similar experience with lenses, acrylic ones are always well made and always work well, (cheap) glass lenses are hit and miss, you can sometimes easily see the surface imperfections, and often the coma in the die image.

At first I thought M4D M4X was talking to me as I saw his post right after mine. I thought WTH? Then I saw the “Zeng@LM” crap. Typical posting you see on the laser forums, too. You’re talking about something in a thread, like a blue laser diode, and the typical “Zeng Lee Foo” pops in with links to some random chaotic crap saying, “try this, try this, it’s flashlight!”

…IT’S SO, |)@NM, ANNOYING.

Eh. Anyways. :slight_smile: I have a sample coming in the mail from them of the new coating, I don’t have any official pricing yet until received. Usually with broadband AR coatings, you might have to give up a little % loss at one wavelength region or another when dealing with white light, since you have 3 color regions spanning the output. So a choice might have to be made. With this stuff, it’s just a flat-line across the visible spectrum (based on the line graph). Exactly what you want to see. I’m hoping tests confirm this once it arrives. Usually blue light at lower wavelengths is the color area where the coating falls off in transmittance a little. So you get a very deep/royal blue reflection from the lens back at you from white light that will be dimmer the better. The red that reflects out is closer to the IR range (where the broadbands usually fall off in transmittance value), which your eyes don’t pick up so well—leaves the blue as all you see. Some coatings fall off further in on each end of the visible spectrum which they can pass, resulting in a pinkish-purple color, like in below photo. Regardless of how colorful it looks, it sure helps ANY lens get a greater total amount of photons through. :slight_smile:

The way I have found the acrylic lenses, is by measuring the OD with a caliper when I find one in a light. They might be 38.25mm on average for a given light, so I search for a “38mm” plastic/acrylic lens, find one with detailed pictures, hold the lens I have in hand up in front of the PC monitor until the scale outline syncs with the photo on-screen, see that they both have the same mold pattern of (3-4) dots on the rim with same exact curvature, and voila. A match. This is just how I have tracked down matches to lenses already found in a light, so I can confirm a source. Then that seller might link to a list of acrylic sizes they carry, and you can assume they’re likely all alright for acrylic. But if I can get the lens from Edmund/Thor in the size and FL I need, it’s probably better (these companies work harder on lens patterns they produce to get them right, which is reflected in their prices). It’s just up to you if you want to pay $40+ per “good” lens and gamble on it working for you. The problem is, I don’t know of too many larger acrylic lenses out there. Those are usually <50mm, then become scarce in any real selection past that diameter.

Big lights just let me use big lens sizes that don’t have to be within a mm or two to work. Turn some spacers and hold a slightly smaller lens if needed.

When I get some extra time I’ll apply some of my tricks to a 140X light and see what can be done. I have a couple other aspheric lights in line on the bench which I want to finish first, but definitely will grab one of these with a chunk of copper bar. :smiley:

Some AR coated optics and one of my apertures—might help a 1405. :slight_smile: For S&Gs…

1/16000 ISO 100 right inside the reflective aperture @ 4A. Dome still on (aperture-testing LED).

Anybody have side-by-side comparison between the XP-G2 beam and a n XP-L/XM-L beam?

Nice one MEM...

Maybe you could be the man that can start selling collars or special acrylic versions for our UF1504(short) or UF1405(long) flashlights?

LOL i just asked about collars for the UF-1405/1504 platform in Linus thread :slight_smile:

But a better acrylic lens for this is also a good idea, i have tried to find some at aliexpress but so far i haven’t succeeded.

The only lens upgrade for this i know of is the slightly thicker lens KKW found at fasttech.

I should mention that the fasttech lens did need a slight amount of sanding on the outer diameter of the rim to fit. Anyone without a belt sander and at least a 220 grit silicone carbide belt needs to set aside an hour or two to do this by hand. If you have the above mentioned items it’s about 2 minutes.

I’d also like to reiterate that there were noticeable ring artifacts in the lens I’ve built into a light. Something to consider if that sort of thing bothers you.

I have one of those that i plan to try out, i hope i got a good one.

I seems the general consensus is that cheap glass lenses very often are of pretty rubbish quality unfortunately.

This is what I have been working with. Well, glass substrates vs metals, and losses/gains through some different production methods. Trying to get something useful that’s still affordable using an adjustable mounting design. The biggest problem for people is in attaining the proper focus of the reflective aperture while mounting it.

I have been working on a much bigger platform design for a RA to sit, though.

Do I have any volunteers in here with caliper and any or all of 1405/1406/1407 models? I would like to get pill dimensions on all 3, also body interior dimensions on all 3. I just finally made my order, so a couple weeks before I even hold one. :frowning:

The higher the “F#” of the RA (I’ll say higher F#, meaning “smaller aperture hole size”), the more tint shift that will occur with the same white LED. If more “white” LED light is recycled back at the die, the ~450nm blue light within it (originating from the InGaN semi-conductor), gets converted to more green/yellow/red light by the YAG:Ce (Y3Al5O12:Ce) in the phosphor. The energy remains from the blue light in the form of its initial eV, but its eV is distributed to lower energy wavelengths by the photoluminescence process. The LED die will not produce or excite any more blue light when light is recycled, because blue LED light does not originate from the phosphor composition, but from the semi-conductor. Blue color, requires electrons to excite the PN-junctions and form, not photons. Throw photons back at the semi-conductor, and you will make electrons. (Hook a volt meter to an LED and shine another light at the die. You have a photo-diode now. :slight_smile: ) So, tint shift will always be relevant to how much blue light is recycled, and the phosphor matrix. As the other colors strike the die upon their reflection, they are not converted any more to longer wavelengths, which I have found in testing by use of monochromatic light.

Mem,

You know that I would took measurements but I sold longer brothers and now I am waiting for smaller ones ( probably you'll get them faster than me).

OK,

I have sourced some really good acrylic 50mm aspheric lenses for the 1406, precision ground B270 glass 50mm for 1406, and also 67mm precision ground B270 glass for the 1405/1504. Also the 30mm and 35mm models should be covered as well with precision ground glass.

Does anyone know the back focal length (lens rear plano side to emitter focal length) for the 1405 and 1406?

If anyone has these lights yet and can get the BFLs (the maximum BFLs at full extension will do), and they are within lens spec, I will go ahead and purchase a couple of the lenses for some test runs.

I will be home tomorrow night, if no-one beats me to it I will measure both lights (within a mm or so).

If i understand what BFL’s is correctly :slight_smile: i think my 1504’s measurement is 42mm, from the edge of the o-ring to the emitter surface.
But because i can’t place the calliper right on the emitter and the edge of the o-ring, i have to just hold it in air & make an estimate, and by my calliper & eyes it looks like 42mm.

But to get a perfect focus on a soldered XP-L on a sinkpad in the brass pill, or should i say as best as this stock lens will get me, i need to unscrew from max zoom about a quarter turn. So maybe the stock lens have an BFL of about 40mm, again if i understand how this works right that is :slight_smile:

I would wait for djozz to confirm my measurement just in case i made a mistake.

I measure it out at 40.13mm to the surface of a noctigon. So the Cree sheets show the LED package base to LED die surface at about .73mm so that would make the total 39.40mm. I also compressed the O-ring a tiny bit to correct for the pressure the lens would likely put on it. But put me in the same camp as cajampa and wait for djozz.

The .68mm added thickness of the noctigon over the stock pad seemed to throw my focus off just a hair and my plan to correct this was to machine the back of the pill just slightly. This of course is not easy to do without a lathe (although I happen to have a lathe) but the opposite of shimming the head lock point for a shorter FL can be done with just a piece of tape so for an easy to fine focus adjustment a little too shallow is better than too deep. Or at least that’s how I look at it.

Also it seems I have the opposite focus problem as cajampa which is interesting, I wonder how the sinkpad vs noctigon thickness compares or maybe it’s that I have an aluminum pill and the brass pills are slightly different, or more likely you can’t expect that much precision from these. Oh and to that point you can probably make your focus land dead on cajampa if you put some tape or something on the part of the pill that stops the head.

Interesting comparison :slight_smile:

Yeah it is weird we seem to have the opposite problem, i wonder if it is because i have soldered my mcpcb & you used heatpaste instead.

I have some aluminium pills coming from n10sivern so i will see if there is any difference on the pills later.

I am not sure i understand how & where i should place the tape to get it to stop at the right focus.

And i very much agree that it is much preferable to have the ability to overzoom than not even be able to get a proper die spot.

Maybe you could use a little less heatpaste or double up on the o-ring.

When you’re zooming out the head it’s stopped by the back of the pill, how the pill overhangs of the size of the body so if you put something on the back side of the overhang or on the area of the head that contacts it, it will stop the zoom when those two faces contact. Might as well be something thermally conductive since heat can move from the pill to the head through that surface.

Pictures borrowed from mholdenattorney.

I’ve thought about another O-ring but it should be pretty easy to machine back the pill but if you were picking a lens a mm or two of adjustment room in one direction would make it so anyone could tune the focus without any machining. The retention ring is quite tight so the paste layer is probably quite thin and I lapped the pill a little to give a smoother hopefully leveller area for better thermals.

Ok, i got where i should be putting some tape or something.

I tried some but one layer or 2 layers didn’t seem to make any difference, i guess i can try adding it on but so far 0,5mm did hardly change the focus at all.

And i am not sure but, i wonder if focus changes by the distance i want to focus at, it seems like it. Maybe a little adjusting room at the spot point is good, not as much as a quarter turn but a little.