M42 with point & shoot digicam

It is interesting to explore the possibilities of some common devices such as digicams and binoculars. I have been reprocessing some old stuff from March. I took 474 single exposures of M42 in Orion through the binoculars with my Exilim digicam. Using a stacking software, all these subframes may become aligned and added accurately, resulting into a 4 minutes long exposure single shot with a perfect star-tracking. I reckon I didn’t use any kind of equatorial mount or motorized tracking. Just an steady tripod. Orion belt passed accros the field of view of the binoculars 3 times. In every gap, I corrected manually the FOV to get M42 inside it as longest as possible.

Orion in Spring

Orion constellation may be difficult to sight in Spring due to its low altitude near the bright west horizon at dusk. Nevertheless I took one subframe of 8 seconds of exposition under ISO-400 applying my new Canon EOS 450d plus 18-55mm lens.

With Paint Shop Pro I subtracted the background gradient due to dusk light. There is visible a pine branch below.

M42 last night

Last night I could enjoy a really clear night sky at Manaluna Observatory. Meanwhile some of my partners were working hard to complete the Messier Marathon, I took 3 series of no-tracking shots through Vixen 12×80 binocular to M42 in Orion.

The truth is that what I could see through binoculars was much more brilliant and detailed than the next image by far. I think my Casio Exilim digital pocket camera is a bit insensible to dim light …

Trapezium is visible as a spot. The 20″ separation among its components is too close for my binoculars to resolve it. Remember that 20″ is the apparent diameter of Saturn.

Background substraction

Astrophotos taken in light polluted skies use to show a noisy gray background that should be avoided mainly for aesthetic reasons, and also to gain contrast in deep-sky objects. Using some image software like Paintshop Pro or Photoshop it is simple to correct the image in 4 steps:

1.- Make a copy of the image.

2.- Level the copy from zero to the highest background noise value. This way bright stars will appear as dim as background.

3.- Gaussian Blur the copy.

4.- Substract the copy to the original picture. You may add a small offset to the substraction if the background removal is very hard.

Here is an example with Orion constellation:

Orion belt

Orion is the most important Winter constellation in Northern Hemisphere. In its center we find the “Orion belt” and beneath, the “Orion sword”. The nebulas located in the area show red colors: horsehead, flame and M42 are visible in this shot.