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How to read/draw in the DARK?


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Hello! It's been recommended to me that, to notice more defined features on DSOs and other objects, I should sketch what I see in the lens. But, how do I do that if it's dark and I don't want to turn on a light??? Are there special "night lights" that are red-hued? What do you guys do?

Also, how do you read? I have a few books ie. Turn left at Orion, atlas of constellations, and the program Stellarium (but that has a night vision feature).

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Red light doesn't ruin the eye's sensitivity to light. The easiest way is to get a LED headlamp and cover it with either a few layers of red transparent candy wrapper, or use something like red nail polish.

Here's a picture of a club-friend doing some sketching with his 6-inch. He has a red clip-on light on his sketchpad. I just illuminated him some extra with my red headlamp as I was exposing with the camera.

post-26290-0-87011100-1414867528_thumb.j

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Hello! It's been recommended to me that, to notice more defined features on DSOs and other objects, I should sketch what I see in the lens.

As a way of noticing detail, sketching certainly helps. Another way is to look for specific features, make a mental description, then switch on your dim red light and quickly write it down. Herschel invented a shorthand for the main features, and all the 19th century DSO discoverers used it - it's what we find in the NGC.

Herschel had another way of saving his dark adaptation: he dictated the descriptions to an assistant (his sister) who wrote them down.

For reading small print on maps etc,if you use a magnifying glass then it's possible to use a dimmer light. Ideally you want a light dim enough that there is no after-image or loss of adaptation when you return to the eyepiece. For that it's best to have a very deep red: if using cellophane etc then you need to be sure it doesn't transmit any blue. With dark adapted vision, "red" filtered light can end up looking far too bright, if too much short-wavelength light is transmitted. A red LED gives a purer and better red. Even better, I have found, is to use a red filter gel (Lee Filters Marius Red) whose spectral transmission is in the far red. I got a roll of it for a few quid, enough to last a lifetime.

http://www.leefilters.com/lighting/colour-details.html#787

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I'm with you on this one Ritzycat....if any light is on its too bright. But folk do favour a red light as described. I've used a head lamp torch with red tape over the lens, but I feel its still too bright.

As for the books and Stellarium, I look before I go out.  I've got an hour for the telescope to cool to ambient, then about 15 mins for the eyes to adapt, and then I  view what I previously studied earlier. Anything else I find, I'll refer to text or the web later. Even red light illumination for Astro Apps on the phone is too bright for my liking. 

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