Observation Log - September 2, 2001 - Tinton Falls, NJ

Links to the Image Index or Home Page.

A full-moon night, but I tried some tri-color photography, just to see what is possible. I hate losing those full-moon and near-full-moon evenings! It was otherwise a good night, with the humidity under 50%. Temperature started at 77F and ended at 57F. No dew at all, and I didn't use the dew heater. The configuration was a little unusual: Dew Shield/Crayford/f6.3 reducer/Homeyer color filter wheel/MX516 camera WITH an IR blocking filter. I used the f/6.3 reducer instead of the f/3.3 reducer because of the filter wheel. It forces placement of the camera much farther back, producing a smaller-scale image. So the f/6.3 reducer with the filter wheel gives nearly the same FOV as the f/3.3 reducer without the filter wheel. -GW]

This is NGC6995 , the southern part of C33, the E segment of the Veil Nebula in Cygnus. The size of this feature is about 12'. This LRGB image was composited from one-minute exposures, using 44 minutes in the luminance channel, 31 minutes in the red channel, 26 minutes in the green channel, and 34 minutes in the blue channel. The 135 individual images were taken between 10:10 and 1:40 a.m. the morning of September 2, 2001. Each channel was calibrated and aligned separately in MaxIm, using a median composite instead of a sum. This gives color channels where the density is more or less independent from the exposure time. The individual channel images were then resampled to be twice the scale of the original images. The color sensitivity of the camera is allowed for by weighting the individual color channels during color compositing, with the R/G/B weights set at 1.80/1.05/1.40, and using the luminance channel set at 80%. The resulting composite image was processed with a color channel alignment adjustement, then a Digital Development filter (FFT, low-pass, medium.) The image was then processed with a color smoothing filter (FFT, low-pass, medium), and finished with a contrast stretch.

This is NGC891 , a galaxy in Andromeda, magnitude 9.9, with dimensions of 13'.5 x 2'.8. Distance is given as 30 million light years. This LRGB image was composited from one-minute exposures, using 45 minutes in the luminance channel, 39 minutes in the red channel, 35 minutes in the green channel, and 36 minutes in the blue channel. The 155 individual images were taken between 1:52 and 5:39 a.m. the morning of September 2, 2001. Each channel was calibrated and aligned separately in MaxIm, using a median composite. The individual channel images were then resampled to be twice the scale of the original images. The R/G/B weighting during color compositing was set at 1.80/1.05/1.40, and the luminance channel was set at 80%. The resulting composite image was processed with a color channel alignment adjustement, then a Digital Development filter (FFT, low-pass, medium.) The image was then processed with a color smoothing filter (FFT, low-pass, medium), and finished with a contrast stretch.