Light box for a 16" Newt

[Quark (Trevor)]

Hi all,
Have just finished my light box, possibly better described as a "crate", project.

The tube for my scope is 22" OD so I have made a plywood light crate 23" x 23" x 24". Internally it is painted flat white. I used 4 clusters of 3 18,000 MCD white LED's. They run on 12 V DC and I am using the bench top power supply that I use for my Peltier cooler. That allows me to adjust the voltage between 6 and 15 V DC.

Being physically quite large I have attached toolbox handles to the crate to aid in moving it around.

I also fitted a plywood ring, the same diameter as the scope tube to act as a spacer and provide clearance for an extension that is on my spider that I sometimes attach a counterweight to. I also have fitted 4 door stops, positioned around the spacer ring, to positively locate the scope tube relative to the crate.

Have attached 4 images of the project.

Image 1 demonstrates the physical size of my creation, note the toolbox handles on the sides.

Image 2 shows the diffuser with the 4 pieces of bread board, the LED clusters with associated resistor, wiring and the strips of polystyrene shielding the direct light of the LED's from the diffuser.

Image 3 shows the diffuser fitted, the spacer ring of plywood and the door stops used to locate the crate with the scope tube.

Image 4 In this image the LED's have been switched on and are operating on just 9 V DC. Probably should have turned the lights off in my observatory.

When I can no longer image Saturn I will turn my attention to DSO imaging with my 450D.
Previously, all of my prime focus DSO imaging has been on 35mm film, but this light crate will allow me to enter the DSO digital age, strewth I must be old.

Cheers
Trevor

[iceman (Mike)]

That's very cool Trevor, excellent work!

Lightbox's are soooo handy for DSO imaging. No waiting for dawn to do t-shirt flats.

[Lester]

Looks good Trevor, you are one step (at least) ahead of me, still have to knock up one of these. Actually on thinking about it, I will need to make 3 for different sized scopes.

[Quark (Trevor)]

Originally Posted by iceman

That's very cool Trevor, excellent work!

Lightbox's are soooo handy for DSO imaging. No waiting for dawn to do t-shirt flats.

Thanks Mike, the only flats that I have taken so far have been with a small lightbox that I used for looking at negatives with, when I piggy backed my 450D on my scope to image the Witches Head. Have not yet used the 450D prime focus.

Originally Posted by Lester

Looks good Trevor, you are one step (at least) ahead of me, still have to knock up one of these. Actually on thinking about it, I will need to make 3 for different sized scopes.

Thanks Lester, this is a whole new ball game to me. The last time I imaged a DSO prime focus was back in 2004 with a 50 year old Nikomat on 35mm film. I imaged a selection of different types of galaxies for a galaxy morphology project for my degree.

Darks, lights, flats & bias frames are things I am not very familiar with, however I have been doing a fair bit of research on the subject over the last 12 months. Looking forward to the challenge of digital DSO imaging.

[Dennis]

Originally Posted by Lester

Looks good Trevor, you are one step (at least) ahead of me, still have to knock up one of these. Actually on thinking about it, I will need to make 3 for different sized scopes.

Hi Lester

If the ‘scope outside diameters are not too vastly different, you could build one flat field box for the largest aperture and then use removable foam inserts to make the one box fit the smaller sizes.

I use closed cell foam, 20mm thick so that I can use my C9.25 flat field box on my (smaller) Mewlon 180. My flat field boxes are actually made from (circular) plastic buckets so I just cut a foam doughnut shape to reduce the aperture to the correct size.

Cheers

Dennis