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Comment by hgsgm | Hacker News Reader

Where can I get 650 to 900nm light?

Is it in common light bulbs?

https://www.aliexpress.com/item/1005001325134202.html?spm=a2...

Cheap deep red flashlights are common, but not reliably described nor, generally, durable.[1] Decent deep red flashlights are expensive.[2] One may also get an inexpensive yet half-decent flashlight that isn't red[3][4], and have an expert modder[5] swap the LED, which very often can be done with a single color hyper red or photo red, 660nm-670nm, LED[6][7].

[1] https://www.google.com/search?q=670nm+flashlight

[2] https://www.zebralight.com/H502pr-Photo-Red-AA-Flood-Headlam... (technically a headlamp, but also a 90° flashlight)

[3] https://www.amazon.com/LUMINTOP-Flashlight-Pocket-sized-Wate...

[4] https://www.amazon.com/Copper-Flashlight-LUMINTOP-Function-W...

[5] https://skylumen.com/pages/modding-services

[6] https://www.mouser.com/new/cree/cree-xlampXPG3-photo-red-led...

[7] https://www.mouser.com/c/optoelectronics/led-lighting/led-em...

Those on mouser are pretty cheap and also probably legit, but 3 milometers across? That's unworkable without a full SMD station. I don't suppose they make them on breakout boards do they?

Edit: Ah they do (but with $50 delivery outside the US lmao): https://rapidled.com/products/cree-xp-g3-photo-red-660nm-led

> but 3 milometers across? That's unworkable without a full SMD station. I don't suppose they make them on breakout boards do they?

It probably comes on a pad. Just to show you, made this just for you.[1] Cree XP-E Red (this one is 630nm). Last two images show 0.06Lm, but on turbo it is very bright, 160Lm. Modder linked in my last post did the swap for me in a ThruNite TiS, but it was the generation after this[2], 0.06 Lm, 12 Lm, 160Lm. The middle mode, 12Lm, is about the equivalent brightness of 3Lm of neutral white, meaning even though 12Lm of red is much brighter than 3Lm white, can see about the same with 3Lm of neutral white due to its much superior color rendition.

[1] https://imgur.io/a/f9JC1Ya

[2] https://www.amazon.com/ThruNite-Tis-CW-Portable-Flashlight/d...

Ah thanks, that looks rad/red alright.

> this one is 630nm

Are you sure, that really ought to be more around 650 nm. I was checking the datasheet [1] for the W2812 just to see how far they go (since I have hundreds around the apartment and can set them to full red) and even something as cheap as those can apparently go to 620-630 nm according to the spec.

The optimal wavelength listed in various articles seems to be more like 670 nm. I wonder if one could just do a longer exposure with a less accurate diode and get the same results though.

> probably comes on a pad

Comes on a reel apparently. Do they think they're selling to people with industrial PCB robots? haha

[1] https://cdn-shop.adafruit.com/datasheets/WS2812.pdf

It's red until compared to real red, then it looks red-orangy. It's an older discontinued XP-E, the first generation of them. Oops, actually, it's 625nm[1] I wanted the Photo Red XP-E, but they were hard to source at the time.

[1] https://www.ledsupply.com/leds/xp-e-emitters bottom of first table.

Look for photo darkroom bulbs but they're very dim, I use my philips hue in my darkroom as safelights and it works (doesn't fog my paper), although it's also very dim

There are many brands, here's one example: https://iredusa.com/product/max

maybe exists but i found some flashlights on amazon. But as always verify that it is not a scam and I can't right now.

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