A lightbox for "flat" reference frames

While waiting for the rain to end , I built a light box for taking "flats". The flat frames are reference frames, used by various processing programs to correct for vignetting, uneven exposure, and flaws in the light path such as dust and dirt on the sensor chip. Nothing too fancy here; the idea is to have a reasonable white light source, diffused enough to provide even lighting. I used an LED lamp with four fixtures and some Dollar Tree foam.

The lights shine into baffles in the top corners of the box, then through two sheets of 1/8" white plexiglass. The lowest layers of foam board are cut out to fit over the end of my scope, which is aimed vertically while shooting these reference frames.

 I used sticky-back aluminum duct tape (real duct tape, not cloth "duck" tape-that's another story!) to line the top of the box.

This is MUCH quicker than correcting vignetting problems in PhotoShop, and does a pretty good job of fixing problems caused by stuff on the sensor in the camera. Since I shoot at prime focus, using a Newtonian scope means that my CMOS chip is actually exposed to open air during exposures; it's going to be getting dirty, period.






Now, once the rain stops...I'll know if my tube repairs were worth the effort, or if all my stars will be shaped like potatoes. I have my fingers crossed, and hard-there isn't much more I can do with my own skills to repair this tube, I'm afraid.