Red Light Torch

[Strath]

Okay, first thing is that I've seen a few threads that question the validity of the whole red light thing.

However, I am going to go on the assumption that a red light is better to prevent the lose of my 'night vision'. Whilst in Maplin, picking up a 2.1/5.5mm DC power plug to make up a cable, I saw a set of bicycle lights from the RAC for £4.99. One red and one clear.

The red light has both red LEDs and a red cover. It seemed a little bright so I've added a layer of tissue paper inside the lens to cut the glare down. The added bonus is that the light comes with a bracket that fits nicely on one leg of my tripod and could also be clipped to a jacket or belt.

The clear lamp is really a set of green LEDs bit could be adapted to give a second light with some red cellophane inside the cover.

I thought this was not too bad a deal since they came with a full set of batteries.

[Blurred Image]

It is a good deal. But my wife painted red nail varnish over the lens of an old torch. It works a treat!

[Capricorn]

Everyone says it has to be red but I find I lose the ability to see as much whether it is red, white or most others. Once read that we should be using green as the eye is most sensitive to that so we could use a dimmer green and green would not affect the red or blue vision.

I managed to get myself a good red led torch, rechargeable and so bright it will blind you at 100 yards - but it is red.

Very few small red led torches out there at present.

[paul schofield]

I just coloured the glass end of my torch with 2 layers of red permanent marker pen and it works a treat.

[nightfisher]

I recently bought the energiser head torch from local wilkinson for the pricely sum of £4.99, this is the one with a decent red led and 2 white one`s, very pleased with it

[stem1989]

It is a good deal. But my wife painted red nail varnish over the lens of an old torch. It works a treat!

Im going to try this

[Tim]

The best amateur observers I know use a really really really faint red light as necessary to read star maps or tick off their lists etc.

Most of the red headlight torches etc you see at star parties are way too bright to be useful.

As an imager I am not that fussed either way, but it does strike me that those who really know what they are doing as regards observing, keep ANY light to an absolute minimum.

Cheers

Tim

[Martin-Devon]

By far the best astro red light I've purchased is the one from the Popular Astronomy website: http://www.shop.popa...gifts/index.php you have to tab down quite a way until you find the INOVA LED MICROLIGHT - £7.99. I've tried many red lights, also the red nail varnish version, but without any hesitation the INOVA red light is just fantastic, big broad red light that carries a good distance as well, all from such a tiny source, two further settings for a dimmer red light and a flashing red light - it's just perfect. I highly recommend it.

[Stu]

That is very true Tim. It needs to be just bright enough to see what you are doing, but will still impact your vision if too bright, or you look directly at it.

I bought a proper astro red light LED years ago which is adjustable so you can turn it right down, works very well

Stu

[BinocularSky]

Once read that we should be using green as the eye is most sensitive to that so we could use a dimmer green and green would not affect the red or blue vision.

It is true that our eyes are more sensitive to green light when we use photopic vision, but when we are observing at night we are primarily using scotopic vision, whose sensitivity depends on rhodopsin. Green light bleaches rhodopsin (aka visual purple) very much more rapidly than does red. (See Fig 4.11 here for a spectral absorption curve of rhodopsin; generally a good article for anyone who is interested in the subject)

Most of the red headlight torches etc you see at star parties are way too bright to be useful.

Indeed so: bright red light also bleaches rhodopsin; just not as quickly as green or white light. In fact, if it is sufficiently bright to be perceived as red, it is sufficiently bright to bleach rhodopsin, albeit very, very slowly.

[adrianelliott]

I have a Celestron night vision flashlight. It cost me 11GBP but the advantage it has is that the brightness is adjustable via a wheel you operate with your thumb. So you only use as much light as you need. It runs off a 9 volt battery, so need to look into how much this will cost to replace each time but LED devices do tend to be fairly efficient.

Prior to buying the Celestron, I tried using some of my girlfriends red nail varnish on a mini flashlight - the result I got was more bright pink than red! Additional coats just seemed to add to the pinkness. Rather than 'go public' with my DIY creation, I put it to the back of my drawer where it has stayed ever since.

[Stu]

That sounds like the one I've got Adrian

http://www.ebay.co.uk/itm/321044062742?redirect=mobile

Works well, can't remember when I last changed the battery, they last ages

Stu

[rory]

I recently bought the energiser head torch from local wilkinson for the pricely sum of £4.99, this is the one with a decent red led and 2 white one`s, very pleased with it

i have the same, i found the brightness about right if i used worn down batteries, new ones seem to make the red light a bit to bright.

i like the idea of headtorch. handy for sketching ,keeps the hands free.

[VigdisVZ]

I use red candy wrapper on my jump starter power tank and headlamp, as taught and supplied by the master Steve Richards himself

[DaveHKent]

I've got one of these:

http://www.amazon.co.uk/Gerber-Recon-Task-Light-Torch/dp/B0006TU75I/ref=sr_1_1?ie=UTF8&qid=1357033382&sr=8-1

Quite nice as it is very small, and you can change the colour of the light to use as a normal torch. I'm not sure what use the blue and green are, but it amuses the kids. It is not too bright either, running off a single AAA.

[Blurred Image]

I did question if the 'red light thing' would apply to me. I've tried it and I do find it makes a difference even with my red/green colour blindness. For those with good to perfect colour vision then other factors may well come into play. My misses is an exceptional artist and she finds that dominant colours cause her to lose perspective on the form of a subject, she thinks it may be that colour vision takes precedence over resolution. She cited some black and white photos that had one area coloured, that one area was by far the dominant element.

So for those who suffer from colour blindness the red light thing still works, for all you lucky members of the human race with perfect colour vision, you may have more of a challange

N.

[jason.p]

This is my effort. A cheapo wind-up torch with nail varnish (needs another coat). If I don't wind it too much the brightness is just right. I'll treat myself to an upgrade one day.

[Mzungu]

old trick is to keep one eye closed when torch is on, then view through that eye...

[scarp15]

I use two red light torches, a hand held adjustable led skywatcher torch and a Petzl elite one led red light head torch. Both can focus a dim light source which is enough for looking at charts etc but will not dazzle either myself or others. I also have some of the cheaper type red torches / head torches, that my daughter and her friends use at star parties. They are quite annoying as they are fairly bright and can disorientate if shone in your eyes.

[Ibbo!]

the LED tend to be too bright and the head ones worn by your friend are normally aimed right in your face

great!

I usually carry 2 one dim and an led if I drop something, which annoyingly is fairly often

Steve

[cantab]

Normally I just use a bike light. Sure it might be brighter than ideal, but I like being able to read stuff easily! I do have a torch that I put a small circle of red paper over, giving an extremely dim and diffuse red light, but that seems to scarcely give more light than the skyglow.