Posts Made By: Roland Christen

Here is my first attempt at the Cygnus bubble first discovered by Dave Jurasevich.

Consists of 7.5 hours of H-a and 5 hours of OIII, STL11K camera, 305mm F3.8 Honders on 3600 mount.
Very much reduced size.

Rolando

Here is my first attempt at the Cygnus bubble first discovered by Dave Jurasevich.

Consists of 7.5 hours of H-a and 5 hours of OIII, STL11K camera, 305mm F3.8 Honders on 3600 mount.
Very much reduced size.

Rolando

Hi All,

Added more data to the image. Here is the overall image reduced to 25% size

Rolando

A local Wisconsin collector car club visited 2 weeks ago and we gave them a tour of the company. Afterwards they gave us a tour of their cars. Several of the cars were noteworthy, so here are some pictures.

Rolando

Driving back from Wisconsin on a lightly traveled rural 4 lane interstate I spotted a C6 coming up rapidly in the left lane. It was the meeting that I dreaded and looked forward to both at once. No cars ahead with good visibilty of 2 miles or more.
Anyhow, as he pulled up next to me I nailed the accelerator, which must have surprised him for a split second, but then he hit his also and we shot along like two rocket ships heading for Mars. By the time I let go of the gas pedal (about 15 seconds into our launch) he was about 3 car lengths back, which surprised me to no end. Love that Roush SC under my hood.

I no longer fear the mighty Camaro - bring it on! Mustango needs more GM nourishment!! Yum Yum.

Had good seeing last night allowed for testing a 305 Mak-Cass on various objects. Normally I would have shot with my STL11K, but I thought I would pull out my ST10XE camera for some high resolution shots, and since people are looking to see how well it works.
This image is 6 x 10 minute Luminance, 305mm F12.5 Mak-Cass, under high moonlight illumination, fairly good seeing. Image is cropped square and reduced to 70% size.

Rolando

Had good seeing last night allowed for testing a 305 Mak-Cass on various objects. Normally I would have shot with my STL11K, but I thought I would pull out my ST10XE camera for some high resolution shots.
This image is 6 x 10 minute Luminance, 305mm F12.5 Mak-Cass, under high moonlight illumination, fairly good seeing. Image is cropped square and reduced to 70% size.

Rolando

Hi All,

Testing resolution limits at my site last week, I did some experiments to see how pixel scale affects max resolution. I had seen improvements in the past on small faint objects like the Einstein Cross when I increased my pixel scale.

Amateurs usually opt for faster focal ratios in the belief that it will increase their signal/noise ratio. They also sometimes bin their color data, i.e. shoot the luminance at 1x1 and the color at 2x2, thinking that the luminance will compensate for the lower resolution color data. Sometimes that works when the seeing is not very good, but even under not so great seeing, shooting at 2x2 does degrade the results.

Attached are 3 shots of the core of M13 compared side by side. All shots were taken with my 12" Mak-Cass and ST10XE camera. I stacked an number of short 10 second unguided exposures.

#1 shows pure RGB taken at 1x1 binning. #2 shows 2x2 binning, twice as many exposures in an effort to get better signal/noise. #3 shows the original 1x1 RGB with 20 seconds of luminance added.

Result as you can see, the pure RGB has the highest resolution. You can see many faint stars that are washed out in the 2x2 RGB. Even though the 2x2 binned image has less background noise, and it is twice the length exposure (giving theoretically 4x better signal/noise) it does not have better signal. There are fainter stars in the 1x1 image. The third image shows how adding just a short luminance set (two 10 sec L exposures) improves the background noise dramatically and preserves the resolution.

I like to use the four stars in the short arc on the right side of the core as a guide to the resolution of the core. These images have not been sharpened or processed except for stacking.

Rolando

Hi All,

Testing resolution limits at my site last week, I did some experiments to see how pixel scale affects max resolution. I had seen improvements in the past on small faint objects like the Einstein Cross when I increased my pixel scale.

Amateurs usually opt for faster focal ratios in the belief that it will increase their signal/noise ratio. They also sometimes bin their color data, i.e. shoot the luminance at 1x1 and the color at 2x2, thinking that the luminance will compensate for the lower resolution color data. Sometimes that works when the seeing is not very good, but even under not so great seeing, shooting at 2x2 does degrade the results.

Attached are 3 shots of the core of M13 compared side by side. All shots were taken with my 12" Mak-Cass and ST10XE camera. I stacked an number of short 10 second unguided exposures.

#1 shows pure RGB taken at 1x1 binning. #2 shows 2x2 binning, twice as many exposures in an effort to get better signal/noise. #3 shows the original 1x1 RGB with 20 seconds of luminance added.

Result as you can see, the pure RGB has the highest resolution. You can see many faint stars that are washed out in the 2x2 RGB. Even though the 2x2 binned image has less background noise, and it is twice the length exposure (giving theoretically 4x better signal/noise) it does not have better signal. There are fainter stars in the 1x1 image. The third image shows how adding just a short luminance set (two 10 sec L exposures) improves the background noise dramatically and preserves the resolution.

I like to use the four stars in the short arc on the right side of the core as a guide to the resolution of the core. These images have not been sharpened or processed except for stacking.

Rolando

I heard lots of buzz about the new 2010 335i, that it actually outperforms the 2007 M3. 1/4 mile times have been posted as low as 12.6 sec for a tuned version, 13.4 sec for a box stock. Met one coming home from Wisconsin on Saturday. He followed me up the on-ramp of the 4 lane and was going to show up another Mustang GT. He hit the gas to come around in the left lane, I let him get almost even with me and then the mighty Roush super charger opened up and Mustango left him to get smaller in the rear view mirror. It was no contest. After we both slowed down, he came up next to me with a sheepish grin and a thumbs up. I don't think he expected that much of a spanking.

Mustango waiting for a Challenger SRT8 meal!

Rolando