sct heart

It's been 7 years since I last saw thru an SCT. If you remove
the eyepiece and peek at the secondary mirror. What do you
see at the center. Do you see reflections of your own eyes
or just blurred image of the aperture or something or just
black. Why don't they make the center black to avoid any
unwanted reflections?

Wat

Watclod wrote:
It's been 7 years since I last saw thru an SCT. If you remove
the eyepiece and peek at the secondary mirror. What do you
see at the center. Do you see reflections of your own eyes
or just blurred image of the aperture or something or just
black. Why don't they make the center black to avoid any
unwanted reflections?

Wat

What do I think? I think you need a new schtick.

Peace,
Rod

RMOLLISE wrote:
Watclod wrote:
It's been 7 years since I last saw thru an SCT. If you remove
the eyepiece and peek at the secondary mirror. What do you
see at the center. Do you see reflections of your own eyes
or just blurred image of the aperture or something or just
black. Why don't they make the center black to avoid any
unwanted reflections?

Wat

What do I think? I think you need a new schtick.

Peace,
Rod


Whats wrong with my question. The secondary of an SCT
is composed of mirror. So if you take out the eyepiece
and peek inside. I don't know if I'm suppose to see
a reflection of my eyes just like a normal mirror in
the 1/2" center of the secondary. I know the mirror
around the 1/2" center reflects the light from the
primary making the beam converge in the focal point
near the eyepiece.

It's just that when the light from the corrector hits
the primary. Only the sides of the converging beam
hit the secondary (that is why you have holes in
the center of the exit pupil). Hence the center of the
secondary doesn't have any reflected light. So how
come they didn't just blank out this center?

Wat

In Article . com
"Watclod" writes:

RMOLLISE wrote:
Watclod wrote:
It's been 7 years since I last saw thru an SCT. If you remove
the eyepiece and peek at the secondary mirror. What do you
see at the center. Do you see reflections of your own eyes
or just blurred image of the aperture or something or just
black. Why don't they make the center black to avoid any
unwanted reflections?

Wat

What do I think? I think you need a new schtick.

Peace,
Rod


Whats wrong with my question. The secondary of an SCT
is composed of mirror. So if you take out the eyepiece
and peek inside. I don't know if I'm suppose to see
a reflection of my eyes just like a normal mirror in
the 1/2" center of the secondary. I know the mirror
around the 1/2" center reflects the light from the
primary making the beam converge in the focal point
near the eyepiece.

It's just that when the light from the corrector hits
the primary. Only the sides of the converging beam
hit the secondary (that is why you have holes in
the center of the exit pupil). Hence the center of the
secondary doesn't have any reflected light. So how
come they didn't just blank out this center?

Wat

Because black hole in black hole is just too much?

Regards,

Rok Vidmar Internet:
National and University Library Phone: +386 1 421 5461
Turjaska 1, SI-1000 Ljubljana Fax: +386 1 421 5464
Slovenia