Re: ATM Re:pinhole vs. slit

["Bob May" <bobmay@nethere.com>]

When you look at the amount of light that comes back to pass by the KE, the
pinhole's amount is going to be a lot less.  From the concept of the
slitless design, the last little bit of the pinhole's curve of the hole ends
up being a few percent of the diameter of the pinhole is what is actually
providing light to a mirror's image for anything near a sphere and this low
level of light is what is reducing the contrast of the image.  The slit
provides a much higher level of light and the size of the source doesn't
change providing that the slit is parallel to the KE.  In other words,
you're getting more detail because the light source is brighter with the
slit rather than the pinhole, the light from the actual used top to bottom
all adding in to provide a higher level of light that you actually see.
Bob May
http://nav.to/bobmay
bobmay@nethere.com
NEW! http://bobmay.astronomy.net