7h 11min 30 s on M42

[michael.h.f.wilkinson]

Yesterday was clear again, so I had the scope snapping along 60s subs for hours while I treated the missus to seafood dinner. Stacked the results in APP, and combined with earlier efforts. The APM 80mm with 0.8x FR and modded Canon EOS 550D might not be a real match for TEC 140s and big CCDs, but I am teasing out more detail slowly but surely. I do find that finding the right postprocessing with curves depends heavily on the monitor used. I am curious to hear what people feel is best.

Only cropping, straight from APP:

The background looks a bit washed out.

Curves 1:

Looks a bit pale in the background on my desktop, but OK on my laptop

Curves 2:

Looks OK on the desktop, but the background looks rather dark and featureless on my laptop.

My "dusty Orion"look. Noisy, but loads of detail in the background. I might try some adaptive unsharp masking on the (linear) FITS files from APP, possibly with some adaptive smoothing, just to see what that does. Should the weather clear, I will be getting more data, for sure. Really curious what happens if I get to 20h or more.

[assouptro]

I really like the dusty one 

there is a load of detail, I can’t help you with processing as I still consider myself a novice. 

But it looks like you have the makings of a superb image 

cheers 

Bryan 

[tooth_dr]

That last one is looking really good! It’s surprising for 60s subs. I’d have imagined you’d have more success with fewer longer subs?!

[ollypenrice]

It's nice to use a stretch which pulls out structure in the outlying parts (Curves1) but, to avoid noise, you'll need more subs. Are you over and out at 60 seconds or would longer subs go a bit deeper? I'd also do some shorts for the Trapezium and follow Jerry Lodigruss on combining them. http://www.astropix.com/html/j_digit/laymask.html

Although this raises eyebrows in some circles, an aggressive stretch does make the most of faint contrasts if you have the signal to support it. (This isn't my invention, it's recommended by several very celebrated imagers, while others keel over in horror!)

The posterization visible at this stage disappears once the curve is applied.

Olly

[michael.h.f.wilkinson]

Cheers for the feedback! I have quite a few shorter subs for the trapezium, and am going to add those in. I will see what 120s subs do. They worked well enough on M45, so I should be able to get deeper subs (if sky transparency and LP allow). The EQ3-2 I am using isn't the best for this. I might use the Vixen Great Polaris next time round (but I like to do some visual with the C8 on that whilst the 80mm is snapping away). I already use fairly aggressive curves in APP, which works on floating point images, and then tweak in GIMP, which is far from ideal (8 bpp, in my installed version).