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Thanks, Jim!

(I posted an earlier rendition of this subject 2 years ago but with improved equipment and skills, I took another stab at it.) The Cigar Galaxy (aka M82) is a starburst galaxy about 12 million light-years away. It's about five times more luminous than the Milky Way and its central region is...

OK, one more iteration, this time with the just-released Multiscale Adaptive Stretch process in Pixinsight. I think it did a fantastic job of stretching the image and I only had to tweak it a little bit afterwards.

M95 is a beautiful barred spiral galaxy about 33 million light-years away, containing around 40 billion stars. Its spiral arms host a flurry of star birth activity and sparkle with the light of countless young, blue stars. This is the result of over 7 hours of exposure time taken on...

I spent a good part of the day reprocessing this image and (I think) produced a slightly better result. The dust clouds surrounding the Angel Nebula stand out a bit more, the color gradients in the hazy star halos aren't as prominent, the bluish tint at the bottom of the image is greatly...

Thanks, Jim. Truth be told, I'm not pleased with the result on this one. I was hoping for much better given that I had 9 full hours of usable data. I struggled mightily with the stretching step, trying multiple times with regular Histrogram Stretch, GHS, and the new Veralux Hypermetric...

The Angel Nebula (aka NGC2170) is a dusty reflection nebula and stellar nursery about 2700 light-years away. It's known for its dramatic appearance, where blue and orange hues intertwine, set against a backdrop of dark interstellar dust and glowing gas. The nebula reflects the light of nearby...

Hi Jim, I couldn't see it in a single exposure, either. I used Stellarium to get the framing that I wanted and did a rough camera rotation to get close. Then I did a fine rotation to match the star pattern in Stellarium and let it fly. No filter - dark nebulas are, well, dark. Filters are...

The "Dark Shark Nebula" (aka LDN 1235) is a dark/reflection nebula made up of interstellar dust which is so thick it hides most of the light from behind it. Just behind the dorsal fin, you can see a distant spiral galaxy (PGC67671). This is the result of 6-1/4 hours of exposure time taken on...

The North America Nebula (aka NGC7000) is a huge emission nebula, a vast region of mostly hydrogen gas, so named because its shape resembles North America. It’s part of the same interstellar cloud as the Pelican Nebula (IC 5070), which is to the right in this image. They are separated by a...

A LONG TIME AGO IN A GALAXY FAR, FAR AWAY… About 40 million years ago, in a galaxy known as NGC 7331, a very large star (at least 8 times larger than our sun) exhausted enough of its nuclear fuel that the energetic pressure from the fusion process could no longer counter the immense...

The Tulip Nebula (aka SH2-101) is an emission nebula about 6000 light-years from Earth. It's close to microquasar Cygnus X-1, one of the first suspected black holes. Cygnus X-1 is orbited by a blue supergiant star (21 times as massive as our sun) which feeds a spinning accretion disk around...

This globular cluster known as Messier 5 is ~25,000 light-years away and contains hundreds of thousands of stars. Stars in globular clusters are believed to form in the same stellar nursery and grow old together. The most massive stars age quickly, exhausting their fuel supply in less than a...

Jim Fox asked me to post some photos of my new mount - a 10Micron GM1000HPS. I finally got a chance to take some decent photos and annotate them, so here they are. Although pricey, this mount has incredible tracking accuracy, as shown in the PHD2 guide plot following the photos. I can't wait...

#1 - Bode's Galaxy (M81): #2 - Cigar Galaxy (M82): #3 - Hamburger Galaxy (NGC3628): #4 - Solar Eclipse Totality: #5 - Solar Eclipse Prominences: #6 - Sunflower Galaxy (M63): #7 - Rho Ophiuch Cloud Complex: #8 - Omega Nebula (M17): #9 - Dumbbell Nebula (M27): #10 - Helix Nebula...

Hi Jim, These adapters thread into the face of the lens where a filter would go. There are intended to enable you to use a filter that is smaller than the lens supports. So they do not affect your backfocus at all. They have the effect of reducing your aperture using a perfect circle, so no...

Get youself a few step-down rings and you won't have those diffractions spike. This $13 ring will reduce your aperture by 51% (so, F2 to F2.8) - that should eliminate most of the distortion from the outer perimeter of the lens. I doubt you really need (or want) to go to F4 or F5/6. That just...

Yep, I saw that - 18 radial spikes (or 9 spikes that bisect the star), confirming 9 blades in that lens. Some find the affect appealing, some don't. It's an artistic choice.

Yeah - those aperture rings are implemented using a set of blades (in the case of your Samyang, I believe it's 9 blades), which approximate a circle using straight edges which create diffraction spikes. If you use a step-down ring, you get the exact same effect without any spikes.

Hi Jim, Just FYI - if you stop down a camera lens, the blades will often generate diffraction spikes on bright stars. I'm not sure if you have encountered that or not (or care about it). If you want to stop down your lens without diffraction spikes, use a filter adapter instead. I have the...