Quote:
Originally Posted by lazjen
Who wears white t-shirts?  However, I'll see what I can dig up in the short term. I was planning on creating a light box, but I need to work out what this problem is now, so I'll try that way. |
Hrmm actually since you're using a DSLR you probably don't need the T-shirt/towel. It's used mainly to create a diffuse light source (if you're using an artificial light source), or to block out enough light so that a CCD camera can take a >= 1 sec exposure - many CCDs have problems with ultra-short exposures, but DSLRs don't.
Just wait say a few mins before/after dawn, point the scope at a featureless patch of sky at say 45 deg alt directly opposite the sun. Turn sidereal tracking off (or use the hand controller and slew east slowly), and take lots of flat frames. Combining a decent stack of flat frames will cancel out the stars (but avoid bright constellation stars).
Light boxes can work great, but they're a bit trickier to do right. Given the choice, I prefer to take sky flats - but if I'm packing up at say 1.30 am because clouds have rolled in, the light box is the only way
