Afocal photography with a "Point & Shoot" camera

After my failed attempt to use a Canon point and shoot camera in prime focus, I redirected my efforts to the afocal method. This method uses a camera with a lens behind an eyepiece.

 

The advantages:

No need to  alter (and possibly ruin) a camera. The camera can still be used for normal photography

More flexibility on the image size. By using different eyepieces, Barlow lenses, etc you have more choices on the magnification and area photographed.

MUCH higher resolutions are possible than with a webcam

Much wider range of exposures possible

 

The disadvantages:

The light passes through two set of lenses - the eyepiece and the camera's lens which degrades the image.

I can't take pictures of the Moon while in the house using Remote Desktop

It's harder to change settings on the camera than changing them on a computer

It's harder to get the focus right - you are looking at a small LCD screen instead of a computer monitor.

It's harder to see what the camera is seeing by looking at the camera's LCD than a computer monitor. (I can run the video to the LCD into a TV, which is quite nice and doesn't have a delay like I had with a web cam connected via USB).

 

Equipment

A digital camera adapter.

A Canon A550 point & shoot camera

A Canon A610 point & shoot camera

A Celestron CPC 1100 telescope

CHDK software

 

 

Results

 

My first successful picture was a photo of the Moon. I used a focal reducer to make the scope work at f6.3 with a 2X Barlow. I used a 32mm eyepiece, and zoomed the camera in enough to avoid vignetting. I had the camera set at ISO 200 and let the camera set the exposure.

The  software allows images up to 64 seconds. Here is my first try of something outside of our solar system. It is M42, the Orion Nebula. It is about 1600 light years away (it takes light that long to reach us. We are effectively seeing it as it was 1600 years ago). I took the photo at full resolution, but cut the size down to about 1/4 of the original.

I didn't have noise reduction turned on, which would have helped. Also, by overexposing it, the stars look so large that they the ones in the Trapezium actually merge.

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