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DIY Lightbox finished

yesyes

By yesyes
in DIY Astronomer

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astrovirus

astrovirus

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Looks great, and seems to perform very well also. I'll keep this in mind (allreay bookmarked it) should I consider v2.0 of my lightbox. I have a spare laptop catching dust, so the panel should be available. How much did the acrylic cost you from Ebay (link perhaps)

Greets Tim

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yesyes

yesyes

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I've paid around £30-35 for the acrylic. Most of that was for the cut-to-size service actually. I've made a list of the pieces I need and then contacted 4 or 5 sellers on ebay to provide a quote including cutting.

I ended up ordering from 2 sellers. The cheapest one (eBay My World - bunaday) didn't have the tools to cut the big round holes. So I ordered everything but theses bit from that seller and the bits with big holes from the cheapest who were able to cut the holes (eBay My World - thewholesaleposco2009).

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yesyes

yesyes

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You could use EL panels of course, but they're more expensive; about £50 for an A4 sized panel which would be enough for a 6" scope but too small for 8". The TFT panel backlight can be salvaged cheaply from a broken TFT monitor / laptop screen and it has a very even light distribution, similar to EL panels.

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Earl

Earl

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You mean instead of the lightbox? Just point the scope at a white screen?

Oh.. hang on..

yeah DOH i think i have missed something here.

Lights are not camera shots like bias there shots of the whole optical system.

oops.

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Psychobilly

Psychobilly

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by taking an image through the optics of an evenly illuminated light source you take what is known as a "flat"..

When it comes to processing the "light" frames from the setup the Software can use this "flat" frame to compensate fro variations in the optical train such as dust motes, vignetting etc as it know that the data should have been "flat" ie have the same pixel values across the entire image...

I reality you take a number of flats and the software combines them statistically to help produce cleaner less noisy master flats...

Peter...

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  • 2 months later...
dyfed0_0

dyfed0_0

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Hi there,

Probably one of the tidiest, homemade light box I have seen and I have been looking and looking on the internet for a good year now..... great job, wish I could be that good with electronics.... lol.

I would be very interested in one please, I have a couple of spare laptops (IBM Thinkpad T Series) but my scope has a 14" apeture so I do not think the screens I have would work (14" diagonal) unlless you join the two up....lol.

The apeture is the problem I have.... any pointers would be great.

Clear Skies

Dyf

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yesyes

yesyes

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Thanks for the kind words. ;-)

And welcome to SGL...

Hmmm, the problem is that the shortest side of the panel must be at least as long as the aperture of the scope. So a 19" flat screen monitor panel would be just enough for a 12" scope. Bigger monitors are usually in wide screen format which just adds to the other length. For example the panel of a 24" monitor is only about 12.5" high. It is also rather hard to find exact dimensions of the panels used in monitors.

I could probably do it but it would get rather big and costly. Let me know if you are still interested and I'll check around what I would need for that size and how much it would be.

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dyfed0_0

dyfed0_0

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Hi there,

Maybe an EL panel may be a better option as opposed to a laptop screen? but I have noticed that they can be a bit pricey as well but I guess they might be cheaper than a wide-screen TV.....lol

Having said that, there may be an alternatve way way to illuminate the box for the larger appeture but without compramising on the width and weight.

I do have to confess, when it comes to tese matters, I am an utter numpty and have no idea what's what. (Paramedic by trade) hence my probably strange questions

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yesyes

yesyes

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Hmmm, these EL panels might be a good alternative for bigger scopes, though, as you say, rather pricey compared to recycled TFT backlight panels.

For a 14" scope I'd need to use a A2 sized EL panel, which seems to cost around £160 for the panel alone.

I've just ordered a relatively cheap 5" x 6" white EL panel to play around with. They say these panels can be cut to and shape/size you want with scissors. I might be able to make round lightboxes this way.. ;-)

There might be other ways to light the box when it's so big. LEDs come to mind but it will be hard to get the light as evenly distributed as with EL panels or TFT backlights.

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dyfed0_0

dyfed0_0

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I totally agree, £160, just for the EL panel on top of other projects one might be doing, for example, I am just getting started renovating and upgrading a Meade Research grade Heavy Mount and also starting to pay for a L200 Spectrometer..... last one the wife does not know about.......lol, basically, she would have little kittens if she knew I was going doen the road of a light box....lol.

I thought of LED's as well, but from scouring the internet on the subject, as you, to get the proper diffusion, the box need to be a lot larger in ratio compared to the one you made (narrow depth)

I am not sure of other options for lighting for the larger apeture but I am sure there are but I am at a loss. Maybe you may have heard of one.

Let me know how you get on please with the EL panel also sorry for being a pain, I just love being a pain....lol

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yesyes

yesyes

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LOL ;-)

The EL panel will take a while to get here, coming from Hong Kong ;-)

I'll keep thinking about how to make a cheap bigger box. The best solution would be if I could buy the diffuser sheets used in these panels in bigger sizes and then just cut them. Then use LEDs behind them. These are 4 or 5 layers of thing plasic sheets with different patterns on then to spread the light evenly.

Another alternative would be using thin, white or frosted acrylic to diffuse the light of, say, super bright white LEDs. I could test that but I have no idea how I could measure how evenly the light has been diffused. I'm quite sure it will not be as good as the panels.

I'll keep thinking .. ;-)

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dyfed0_0

dyfed0_0

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Funny you should mention a white diffusing acrylic/ plastic sheet, seen a few boxes with just that type of material used to spread the light evenly and they are using LED's, dont know the load of the LED's but I am sure they were very bright ones.

Something to ponder about......lol, Ill keep scouring the internet for ideas and throw them in the mix as and when I find something.... (no point in me pondering, havent a clue....lol, ill steal some ideas off the net.....lol)

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yesyes

yesyes

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The small EL panel has arrived yesterday so I'm going to start playing around with that this weekend.

Regrading the LEDs behind acrylic, would it be enough to take a picture of the illuminated area and then overstrech the histogram and play with curves to see how equal the illumination is?

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dyfed0_0

dyfed0_0

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To be honest, I have only just really learned doing flats with a white t-shirt and trying my best to get the twilight light to do them, but as I am sure everyone accross the country will agree with me at the moment wit this comment "I WISH THIS blumming RAIN WOULD GO AWAY".....lol

Hence the massive interest in the light box you have constructed as it would take very little room in my Obsy where a massive box would really be in the way.

I was even thinking, there would not have to be a massive apeture opening with it, just a border/ sides to hide shadows and because it will be so close, if hung on a wall for example, the EL, could in theory be large enough for the appeture... dont know, clutching at straw....lol

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