Carina Nebula with a 127mm saxon FCD100 triplet refractor

4 March 2019

This is another "you can do it!" post.

If you've been following my Facebook posts, you will remember that I wanted to show what you could realistically expect from your own DSLR attached to a telescope, in a light polluted city.

I took an admittedly large saxon FCD100 127mm refractor out into my front yard, got a reasonable polar alignment and started taking photos. I've already posted the photos I got of the Jewel Box.

The photos I'm attaching this time are of the Carina Nebula. I think this is the second brightest nebula around after the Great Nebula in Orion, and it's in a good position to be seen right now, being high in the South (and above my neighbours' roof).




The single shot I'm starting with was taken with a plain DSLR, 10 seconds at ISO 800. Out of the camera, there's really nothing much to be see, and a lot of people get turned off by this, or try to take a longer exposure, and this can run into tracking problems.

Don't lengthen the exposure! A short exposure helps with tracking and prevents damage from light pollution. The data is in there, you just need to drag it out.

... and don't get put off, either.

My camera came with some image processing software, and as long as you shoot in RAW mode, you can reach into the black and find those mysteries.

In this case, all I did was to increase the exposure, and bend the histogram a bit so the blacks stayed dark, while brightening the lighter bits. Nothing too complicated, and the nebula appears as though by magic.

For the last photo I did go a bit nuts. It's a "stack" of 190 identical photos (I was out there all night), with all the processing technology I can muster onto it (including Astro Pixel Processor and Photoshop). It's also a slightly wider crop.

To be honest, apart from being a bit brighter, I'm not sure that all that processing adds a lot at this resolution, does it?

I'm not kidding - all you need is a telescope on an equatorial mount, a DSLR in RAW mode, a $30 t-ring and some patience.

Ask me how!

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