Instructables

Astronomer's red light (Maglite mod)

Picture of Astronomer's red light (Maglite mod)
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I've taken some interest into amateur Astronomy recently and came to realize that, as a hobby, it can get very expensive very very fast. The amount of equipment available at any price range is tremendous and just getting started can mean dishing out some serious money. Learning as much as I could before deciding what kind of equipment to purchase I found astronomers use very dim, red colored flashlights as to allow for their eyesight to remain as adopted to night-time vision as possible. Since every penny worth saving on other equipment equals more aperture for your scope I decided to make a very simple red filter for my, already partly modded (with LED) Maglite.

Time required for this project: 1 hour
Cost: $0 (I had everything on stock a.k.a. rubbish laying around)

 
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Step 1: What you'll need

To make this you will require at least:
- MAG LITE MINI with an LED instead of the regular light-bulb.,
- A thin layer of acrylic foil. I got mine from a broken ATX power supply. Should be about 0.5mm thick,
- Dark red nail polish... preferably the one your spouse does not like too much,
- Thin magic marker,
- Scissors,
- Fine grain sandpaper

Additionally, I ended up using some duct tape, nail polish thinner and a pair of equally sized plates of glass to press the two chips together.


I would recommend against making this mod with a classic MAGLITE light-bulb installed, as I remember it heating quite a lot as opposed to a bright LED. Than again if you should want do, you could simply change the light-bulb with an already colored red LED and go about it that way.

Step 2: Step 1: Disassembly

Disassemble the top of the MAGLITE. Only remove the very top ring that holds the glass plate in place. There is no need to go any further than that. You should end up with 4 parts as shown below. The ring, reflector ( which is basically useless for a LED mod, but looks better ), the lens and the rest of you MAGLITE.

imkwl123453 years ago
perfefct fo trying to hide in the dark while playing lazer tag :D
lemonie5 years ago
It obviously works, but looks a bit opaque. Had you considered something more translucent like this?
http://www.shopwiki.co.uk/Jewellery+Making+%3A+Dip+Film

L
Lftndbt lemonie5 years ago
You want it opaque. Any brighter and you will have ppl throwing rocks at you in the dark... Astronomers don't like bright lights, trust me.
lemonie Lftndbt5 years ago
Dimmer bulb then. Or a red LED... L
vincenc (author)  lemonie5 years ago
Brilliant idea, thank you. I will definitely give that go seeing how I still have some foil left over. I probably would have used that had I had any. This was just something I decided to do without any preparation only to help me kill time, waiting for my new telescope to arrive. :)
Lftndbt5 years ago
I love astronomy. Do any astrophotography? This is my best effort so far, only got my scope 2 weeks ago. This is taken with a 4yr old sony cybershot... Nice I'ble!! I need to mod two torches tonight, thanks.
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vincenc (author)  Lftndbt5 years ago
I used to own a very old refractor which was practically unusable for anything but the Moon and a couple of planets. This was a fair while ago so this is going to be my first "real" telescope. I hadn't done any astrophotography, but plan to at the very least try it out once the equipment arrives, which is a bit a sad story of itself since I've received word that they've located a defect upon inspection, hence delivery will be somewhat delayed. Fingers crossed.
Lftndbt vincenc5 years ago
"they've located a defect upon inspection, hence delivery will be somewhat delayed." Oh you are mistaken my friend, that is by far some of the best news you could here... Believe me you would be cursing if they didn't pick it up and sent it out like that. This was shot with a budget 70mm x 900mm refractor.
vincenc (author)  Lftndbt5 years ago
Funny you sound just like my reply to the supplier: "Dear Sir, it is also in my best interest to receive a properly working telescope, so you have my sincere thanks for your professional attitude in checking the equipment before shipping." The weather forecast is also quite bad for astronomy this weekend, so it's not too bad.
snorkledorf5 years ago
I've done this in the past with lithographic tape (red). It's just like red Scotch tape, made for the printing industry. It comes in several widths. I used the 1 inch and put it on the inside of the factory lens. One roll (60 ft) will do many flashlights.
loximuthal5 years ago
I went even simpler: nail polish straight onto the lens of a handy flashlight. All done! I'll bet this one works even better than mine, but I was feeling lazy.
vincenc (author)  loximuthal5 years ago
In all honesty I started out exactly as you, but figured, I am bound to do something wrong, so I best cut two equal parts just to be sure. Decided only later on to try pressing them so that there would be no chance for the nail polish to get glued to any part of the torch.