Another light box

[Shelster1973]

Having seen other people efforts (mainly inspired by @Horwig in this thread) and having issues with the flat panel I was using, decided to bite the bullet and make a bespoke light box.

Started off with some plastic boards that I managed to get cut at a local supplier for not a huge amount of money (£13 in total for all plastic) which consisted of the side and base boards and 2 x opal perspex sheets.

I originally wanted the sides to be 50mm tall, but the company I used can only cut to 100mm as smallest, so use my table saw to notch some groves in that one of the opal sheets slots into.

Is nothing major on the construction, just 4 walls glues together, opal sheet slotted in and then one glues to the bottom of the box.

Lighting comes from a 5m LED strip that I grabbed of Amazon.  Have snaked it around the bottom panel, so it should provide an even illumination.

Final stage is to construct a collar that the OTA will slot into.

Here are a few pictures.

Have not had a chance to stick it under my CCD yet to see what the illumination is like.

Also have a PWM dimmer coming so that I can adjust the brightness of the panel.  The above was taken with it running off a 9V supply...it should be 12V

[Horwig]

Nice one, looks very even, looking forwards to seeing the end results

 

Huw

[richyrich_one]

Be aware a PWM will likely introduce flicker which might be picked up by the camera. IMHO a buck converter would be better if you need to reduce the voltage.

Nice job though.

[Shelster1973]

On ‎24‎/‎03‎/‎2017 at 19:47, richyrich_one said:

Be aware a PWM will likely introduce flicker which might be picked up by the camera. IMHO a buck converter would be better if you need to reduce the voltage.

Nice job though.

PWM arrived and was fitted and there is no discerable flicker to the eye.

Had an issue with the antibloomming voltage on my CCD which meant that any flat I tried to take that was longer than 2 pico seconds coused banding, but hopefully have this sorted now.  Not had a chance to re-test due to other things getting in the way, but hopefully will be able to have a trial soon.  Will be able to see if there is any flicker issue picked up by the CCD then and also what the illumination and field look like

[Horwig]

On 06/04/2017 at 16:00, Shelster1973 said:

Had an issue with the antibloomming voltage on my CCD which meant that any flat I tried to take that was longer than 2 pico seconds coused banding

Glad you have it working. I had MANY sheets of white paper between the light source and the scope.

Huw