Tuesday, January 11, 2011

Canon T2i (550D) First Light

After agonizing for several days over the Canon 60D vs. the 550D (T2i), I decided on the latter. Here's a first light image:

I think it's a terrific camera.

Bill Shaheen
Gold Canyon, AZ

Tuesday, January 4, 2011

The Horsehead and Conventional Wisdom

Conventional wisdom says that when shooting flat frames one should
not rotate the camera or in any way change the optics. I certainly
wouldn't argue with that but as an unexpected opportunity to image
the Horsehead came up the other night I just had to capture it in
all its glory. And, even though I had just put together a master flat
of 32 frames the previous morning, the one flaw I saw seemed to be on
the camera's filter. So, I took a shot and here's the result of 12 -
12 min. subs:


Now, I'm not advocating this as a matter of practice. But, consider
that since I'm using a refractor and did not have a focal reducer in
the light path, the nearest optic after the camera and filter is the
telescope's objective, which is 3 ft. away.

At any rate, I think it turned out pretty well. Of course, the darks,
bias frames and chilly temperature (for me) didn't hurt.

Adaptive Richardson-Lucy deconvolution demonstration

I've never been a big fan of altering images with photo-shopping techniques, other than an occasional mild sharpening and maybe contrast enhancement with a curve adjustment.

But there is one with a good deal of legitimacy - the Richardson-Lucy deconvolution algorithm -  a software method of enhancing images that was developed to correct the Hubble telescope's originally flawed optics. 

Here is a flashing comparison of an image taken last night before and after applying the algorithm (using ImagesPlus v3.82) -

Here is a still of the finished product:

Note that this is also the product of a nearly 2 year effort to image at close to 1 arc-second/pixel resolution (versus previous 1.4 as/p).

Jupiter in HD

Up to now I've been using the venerable Philips SPC900NC webcam for imaging planets. At 640x480, it produces reasonably good images.

This video, however,  http://www.youtube.com/watch?v=Z0CXFbIKbKU   was taken with the next generation of webcam - Logitech Webcam Pro9000, at 1200x1600. Although it has been downsampled to a more common 720p (1280x720) format, it's still not too shabby.

The imaging train consisted of a Televue 4x Powermate and an Orion Sirius 17mm Plossl eyepiece.

As a side note, I'm very impressed with the performance of the Celestron EdgeHD 9.25" and its ability to support insane magnifications. Earlier one morning, I observed Jupiter with the 4x Powermate and a 13mm EP for a mag of 552x and the image was excellent. This compares very favorably with a high-end APO refractor I once had.

Attaching a video camera to a telescope

Being duly impressed with my new Sony video camera (HDR-CX150), I just had to
try it out at the telescope. Hand-holding the camera up to the eyepiece showed
possiblities so I immediately thought about how to attach the camera in a solid
fashion. After some research to determine the specs of the threaded front
(30mm), I shopped around for a step-up ring to mate to a standard 42mm T-ring.
When I couldn't locate one, Jim Henson at ScopeStuff suggested he could assemble

Here is a picture of the set-up:
The eyepiece projection adapter houses a 17mm eyepiece.

And here is a brief clip to show the results:

Of course the quality of the video is mainly determined by a number of factors
other than the means of connection (image quality, optics, procesing skills).
And the same could be achieved using a DSLR with live view. But, this new
adapter provides a solid, secure way to connect any T-thread device to an HD
video camera.

The product code at ScopeStuff is TTSH.

Comet 103P - Hartley2

Details and link to video here:

The field of view is approx. 26.4 arc-minutes. So, this puppy was moving pretty
quickly - timespan was 1.5 hours.

By the way, with the new autoguiding set-up (Lodestar/Stellarvue 50mm Barlowed),
I'm getting an RMS of 0.42 arc-seconds. Compared to the Q-Guide (QHY5), the
Lodestar is *much* more sensitive, presents cleaner images and downloads a lot
faster, which seems to improve the responsiveness of sending corrections to the
mount. With the previous QHY5, PHD would exhibit delays.

The power of resolving power (aperture rules - again)

It broke my heart to sell my TEC-APO140 (a premium 5.5 inch apochromatic refractor).  And I still recall a fellow amateur astronomer saying, "I'd take that scope to the grave".  (I nearly did when I told my wife I wanted anther telescope.)  But, numbers don't lie and I was after improved resolution and contrast in my deep sky images.  So, I decided I wanted the increased resolving power of the larger aperture 9.25 inch SCT over the 5.5 inch refractor.  Besides, the new Celestron EdgeHD series promised sharp stars across the entire field-of-view (FOV). And they delivered.

So, bracing myself for a complex conversion (new accessories, focuser, etc.),  I sold the TEC APO-140. The new owner says it provides better views of planets than his 12 inch Meade SCT. 

While imaging last night, it occured to me I could perform the below comparison, using an image taken of the Horsehead with the previous scope back in January.  Here is a side-by-side:

Here is the work to date using the new telescope:

I feel the changeover was worth it.