Push LED Light for Lightbox?

[gfletcher]

Hi Guys

Would you be able to use one of these push on/off LED lights for a homemade Lightbox ?

thanks

Graham

[Milamber]

Probably - they are certainly bright enough (if you mean the UFO-type ones) but they will derfinitely need a diffuser of some sort (like some sheets of thick paper) to even out the light so by definition the further away you can get the light from the diffuser the better.

Arthur

[Psychobilly]

Yep they work quite well use un-cooked laminating pouches as diffusers...

Theres a couple of "DIY" ones using them here if your after some inspiration...

Peter....

[Aza]

Here is the lightbox I made:

Light Box

And here is the light I use (purchased in B&Q)

Eterna 3W Circular Fluorescent Battery Light With Push Switch D049 White (H)45mm x (W)140mm, D049

[gfletcher]

Hi Arran

Was the lightbox for your 8" Newt

Graham

[Aza]

Hi Graham. Yes it was made for the 8".

I also use it for the WO72, but of course it doesnt fit so snugly on the end of the scope

[gfletcher]

Thanks

How do you attach it to the end of the Newtonian ?

Graham,

If i could not get hold of draghting vellum is there anything else i could use

[Aza]

Its not attached as such. I just point the scope straight up and it sits on the end of the scope. Its all light weight and has worked fine for me so far.

If you have any art or craft shops around, you should easily be able to find some material to use as the diffusers.

[gfletcher]

Thanks Arran

Would laminating pouches or even tracing paper do for the diffuser material do you think ?

Also, am i right in thinking that after imaging through my 8" newt, as long as i do not move the camera, it is ok to move the telescope vertically before taking the flat image?

How many flats do you take, and what setting do you put on your DSLR for taking flats.

Sorry for all these questions Arran but i am trying to fully understand the procedur for taking flats.

thanks

Graham

[Aza]

No worries Graham

It was awhile ago when I made this, but yeah I think I may have used tracing paper myself. As far as I know its ok to move the telescope. Like you say, the important thing is not to move the camera or focusser.

I usually take about 15 flats, not sure what the correct amount should be though.

As for settings, you should expose the shot so it is halfway along the histogram.

For me this is usually 1 second on ISO100. However this length goes up when the battery power in my light starts dropping.

As long as the histogram is halfway, you should be fine. You will be able to see if the flat looks ok.

Here is one of mine: (it looks a little different due to being a jpg etc)

If you open it up into a graphics program, you can see about the histogram.