Tablets & smartphones at the scope. My dark adaption suffers...

[Russ59]

During my lead up to an observing session in Summer I take small steps to assist in my dark adaption. While I don't go overboard, a typical evening would be - say from 8pm onwards no watch TV or use a computer. Set up the scope and start cooling down, turn off all house lights in the house and sheds and only use my trusty red torch. I've read of observers wearing eye patches but for my I find those methods excessive.

The brightest light I work with is the Arvo Navis on the dimmest display setting and a dim red torch - probably typical of most amateur astronomers, right?

So, for the first time last night I decided to use me iPad assorted apps to assist me at the scope. Well even pre-setting the apps to a red screen and iPad brightness to minimum, my dark adaption was shot to pieces!! I was trying to observe some faint DSO and it completely ruined my observing session!!! After about 30 minutes I tried to use a friend's Windows tablet that she had set to minimum brightness. Nope, no good. Same result!!!

I understand you imagers need computer screens for your imaging at the scope and perhaps complete dark adaption may not be critical, but for visual observers, how do you use these devices???? I'll be sticking to my books, charts and a red torch from now on!

Cheers,

Russ59

[glend (Glen)]

First up I have to say I am a visual observer only so my eyes are my tools. I use a smaller tablet (Nexus 7") running Sky Safari Plus (which has red screen night mode, and I can turn this up and down as well). The tablet is stalk mounted on the Dob base. This works well for me, and being a smaller tablet seems to not throw out anymore light than a red led torch. But I have to use this setup as it is part of my wifi pushto system, which works fantastically. It is important to have your app running early in your setup (adapt time) to avoid the screen brightness in normal mode). I tend to use my left eye primarily for the eyepiece simply because it is my better eye, and most older people have one that is better than the other. You can try leaving your good eye closed except when viewing through it.

I simply don't carry charts etc with me anymore as Sky Safari has everything I need, and the charts reflect red light as well. If your observing in a metro/suburbs environment I am not sure that obsessing with dark adaption is going to gain you much, where a street light down the road might catch your eye occasionally, or a neighbor may turn on an outside light. Yes it does help with objects such as the Horsehead nebula which is dark on dark, but scope limiting magnitude, seeing conditions, and light pollution are (in my opinion, and assuming a home viewing session) much more of a factor than dark adaption obessions.

However, dark adaptation is important in very dark sky locations, usually found at Star Parties, Astro Camps etc where you maybe trying for objects which just are not visible from your home. Of course the other people there will be very concerned about their night vision so discipline for everyone is important. It only takes one person opening up a car door to illicit groans from other people.

[acropolite (Phil)]

When I use my iPad or smartphone I always use red gel and turn the brightness to minimum. Whether it has any effect on dark adaptation I can't be sure as I mostly do imaging.

[astroron (Ron)]

IMHO computers and other devices at the scope are a No! No! at or near the eyepiece.
Looking at a computer screen however dull red severely spoils any dark adaption you may have.
I use a ARGO NAVIS which has the very small screen set at 4 out of 100,it is usually about 50 centimeters away from my eye,but still effects me if I am looking for very faint,Faint Fuzzies, I have to wait at least 20 seconds or more to get the object into view after reading the screen.
When I get people up here in Cambroon and watch how bright the computer screens are,I think to myself,no wonder they can't see what I see, and I have old eyes.
Cheers
PS This applies only to visual observers, most imagers just don't need to bother as their imaging area is usually lit up like Sydney Harbour.

[AG Hybrid (Adrian)]

I use an App called Screen Filter to dim the screen of my Nexus 4 and Nexus 7 further then the default minimum brightness. Works well even in Sky Safari.

[Russ59]

Thanks for the replies,

Glen, I split myself between country Victoria and on occasions, the northern suburbs of Melbourne. 80/20. So light pollution is not a big problem. at home light pollution (street lights etc.) are not a problem.

I have noticed that the screens on these tablets cannot be turned completely off - i.e. with the brightness at minimum there is still a screen glow. Anyway each to his own, if you have a use and end they enhance your observing good on ya

acropolite, a good idea with the red gell there. Is it cellophane or the red gell that lighting technicians use for colouring lights?

AG Hybrid, I will look for an iphone app later. Hopefully there is an equivalent one to the Screen filter.

Ron, I guess you are similar to myself. Honestly have no use for electronic devices at the eyepiece. My last star party was over twenty years ago, so back then these sort of devices didn't exist!

[stephenb (Stephen)]

Russ, good topic! As a visual observer I cannot use these screen devices. I find they do affect my dark adaption, and I need all the dark adaption I can get! I know where you're coming from.

Yes I also have an Argo and like Ron I have it set to the lowest brightness setting.

Horses for courses, naturally!

[killswitch (Edison)]

I use Screen Filter as well. Im sure there is an Apple equivalent.

Cellophane will work but photography gels (red acetate sheet) might be easier to work with. You can make some yourself using clear acetate sheets and just printing red on it.

[acropolite (Phil)]

acropolite, a good idea with the red gell there. Is it cellophane or the red gell that lighting technicians use for colouring lights?

Red lighting Gel, not sure where it came from Ponders got me a sheet years ago for Astrofest.

[RAJAH235]

Why not try grey automotive window tint/s?
They come in various densities & they usually have lots of free off-cuts/left-overs.

Plus, you can read the "red" bits on your charts.


Happy New Year to all.

[Russ59]

Thanks for all your advice re: the red screen issue. A couple of products I'll certainly try but I think my main hurdle is that I'm just not that flash with technology I can use it but I like things basic and uncomplicated.

[MortonH]

I was messing around last night with a tablet. Had Stellarium with the night mode on and it was good. But accidentally hit the "back" button which exited the app and everything went bright white!!!

Reckon a physical red filter over the screen is better to avoid such mishaps.

[multiweb (Marc)]

Been using a red perspex screen for a while. I don't like the red schemes as they don't always dim out all the task bars or buttons.

[Astro_Bot]

I have both red and neutral-density gel - it's not really like a gel, in case you were wondering, but that's what it's called.

Got mine from a theatrical/film supplies store in Brisbane - I'm sure there'll be a similar store in every capital city. In case you can't find it closer:

Lee Filters at Production Shop

IIRC, I chose Primary Red (9.3% transmission) as my red filter - they provide a transmission spectrum for each product, so you can pick the filter that best meets your needs.

I made a cardboard frame for mine using thick card stock from Office Works.

Edit: I can't remember the exact sheet size (they cut it off the roll anyway) but one sheet was enough for 4 laptops.

[kittenshark (Cheryl-Ann Tan)]

Sorry to pull up an old thread again, but I saw these http://www.greatredspot.com/Red%20Eyes%20Filters.htm and I wonder if anyone stocks the static cling ones locally and if they work any better than the Lee Filters (aside from the fact that I don't have to fumble with rubber bands/sticky tape/velcro to attach them). The ones on Great Red Spot seem pricey for what they are, and then there are shipping costs... I'll need one for my ipad, phone, and the LCD screen on my DSLR. Might want one for the laptop but I probably won't be using it with the scope.

After reading Dennis' writeup, I think the using 2 neutral density filters is the way to go, but I wonder whether using a red one would have fewer rocks thrown at me when I power up the ipad at Astrofest? Which would be dimmer?

[The_bluester (Paul)]

I use red lighting gel that I bought off ebay, to keep it in place I use "Photo Leim" glue which is a soft and neutral cure removable glue that dries clear. When you peel the gel off you can rub the residue off with a finger.