ASTRO: Rosette Nebula

Rick, Robert, et al:

The few times I used a Canon Rebel DSLR I had no problem focusing the
moon (6" F/12 Astrophysics refractor), and with my 28mm-200mm lens I would
just focus at full zoom, and then zoom in. If you can live with a PC I
believe that you can control the camera directly with the PC and focus as
you would with an astro CCD camera. I'm not sure if I remember this right,
but I believe that with the Hutech camera you need to add a filter for
"critical" normal photography to get rid of the IR, but with the Canon D20a
you can just white balance with a white card. Either will work.

I recently saw an article about a new DSLR intended for police
investigative work that has extended UV/IR coverage. I'll have to look up
the details, but I thought that it might make a good astro camera.

George N

"Robert Price" wrote

Rick,

For focus I have settled on the Hutech knife-edge focuser. I have had
good focus using Jupiter, Saturn, and the Moon. Focus on bright stars
is hit or miss. My 300mm f/4 Canon lens will auto focus on bright
stars.

The Hutech modified Canon 350D camera, with the extended red filter,
is said to be able to take normal photographs using a modified white
color balance. I have not tried this, so I do not know how well it
works.


On Thu, 23 Nov 2006 02:06:08 -0600, Rick Johnson
wrote:

Digital cameras look about to kill the one shot color CCD market from
results like yours. How does the modified camera work for ordinary
snapshots? I'd never get such a camera by my wife unless it could pull
double duty. How do you find focus with such a camera? Does the
viewfinder blow up the image so you can see enough to focus on the view
screen? When I've tried to take planetary shots through the old Cannon
my wife uses the view screen was way too small to tell good focus, even
when I used the magnify function. Only way I could make it work was
connect it to a TV and use the magnify mode. Then it was large enough
to sort of tell when it was in focus. Still I'd take a range of focus
positions to get one or two that were sharp. Focus masks didn't seem to
work either. I just couldn't see enough in the view finder to tell when
the three images merged. It would look good until I took the photo.

Rick






Robert Price wrote:

Taken using a Hutech modified Canon 350D (400ASA) and TeleVue NP-101.
Exposure was 611 sec 30 Oct 2006 from a location near
Blue Knob state park PA.