805mm focal length with a .8x field flattener for about 644mm. 115mm aperture. This is cropped quite a bit.

Definitely watching the weather. Last year in October, we went out to Amboy and it was 105 at 5pm and was still 100 when I gave up and went home at 10pm

I've been using my Nikon D750 but just pulled the trigger on a zwo ASI6200MC. More, smaller pixels and a cooled sensor. Can't wait to play. I'm thinking about going up to death valley in May.

Richard,
Here is a screenshot of Stellarium showing at the time and date the picture was taken. I ran it through Astrometry.net as well, but it did not give as good context as Stellarium did. The location was the Amboy Crater parking lot, about Bortle 2

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Very nice. Thanks!

Thanks, I was going for minimal color modifications to try and get a more natural color. Looks like I need more subs to get the red in m82. Waiting for clear weather and no moon again. We've had a cloudy winter for southern California.

While setting up for M81 and M82, I took a couple of snapshots of the comet. This is 120 seconds iso 400 (644mm focal length at f/5.6) and is unprocessed, SOOC. I did convert it 8 bit to get under 20MB. It gets nice and dark out in the desert.

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Finally had some clear weather near a new moon in Southern California. We went out to Amboy Crater, south of I-40 and north of Joshua Tree National Park.

The weather was perfect, mid 60s temperature, almost no wind and very clear and very dark. This was 140 exposures of 120 seconds each.

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OK, I double checked and it looks like the Z8 has a pixel size of about 4.3 microns. To get 1 arc second resolution, the telescope will need to be a minimum of 900mm focal length.

an 8 inch SCT has focal length of 2000mm, so this looks pretty doable.

I think I may be off a factor of ten here. I'll redo later and repost for a z8 class sensor.

If my back of the envelope calculations are correct, to get a 1 arcsecond resolution with a standard pixel size of 5.7 microns(24 mp full frame), I would need a telescope with a focal length of more than 10 meters.

I don't know, but I know it when I see it. :)

Here is sample of one of the raw images to give you an idea of what the stacking and processing can accomplish.

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Here is a shot of my setup for this shot.

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Sounds familiar to me as well. When I was a kid, I asked my folks for a telescope. The department store junk I got put me off of astronomy for many years.

When I finally bought another telescope I got a Meade 8 inch Schmidt Cassegrain with a manual mount. It was decent for visual observing if a bit frustrating to align and find objects. Typically high magnification and the manual mount made tracking frustrating and images bounced around a lot. Living in southern California also made it very difficult to see anything but the brightest objects.

When the kids were small I got my hands on a 12 inch piece of Zerodur, intending to grind a mirror and make my own scope. A few years later, I dug the glass out of the closet and traded it for a Japanese made Vixen SX-2. It was light weight and had a nice controller with a nice display including a sky map. Again, very nice for visual, but the stereotypically awful Japanese software made it challenging to use for astrophotography.

Like you, I found I was more attracted to deep sky nebula and galaxies, so the 8 inch was replaced by a 4.5 inch triplet. With the field flattener it is 600mm focal length and gives me nice sharp images across the entire frame.

The raw images were looking good, but processing with deepskystacker and photoshop was very frustrating as I could not get anything to look much better than a single image.

About this time, the Vixen stopped communicating with the computer entirely. I wanted an Astro-Physics
Mach2GTO or Software Bisque Paramount MyT, but other obligations made spending over $10,000 not practical . I ended up getting a Skywatcher EQ6-R pro and have been pretty happy with it so far. I've only had it about 6 months, so still think of it as new.

I'm now using N.I.N.A to capture images and it works really well talking to the mount, camera, tracking camera and focusing motor. I'm still learning to use the automation features in N.I.N.A. to set up an imaging session and have it run basically unattended. That said, the images I took of M101 were done hands off once the mount was lined up. It took 10 images, refocused, then 10 more for a total of about 70 images. I'm still using my standard Nikon D750 for the camera, but I can already see a new camera (Cooled CMOS, monochrome and filters) in the future.

With the good glass and a decent mount, I've been getting more, better raw images, but still in post processing hell.

I finally broke down and bought Pixinsight to process with and the learning curve is very steep but the results are worth it.