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This version of the Horsehead Nebula was processed using
Gendler's technique of layering the Ha (75%) and Red (25%) images as an enhanced red image (in Photoshop). Genler
discusses his technique at his web site, http://www.robgendlerastropics.com/ (the photographs are increadable and a good deal of useful imaging
techniques are described). Using his technique, no color management of this image was necessary, in contrast to the
previous image, which required a great deal of management. The resultant images were then combined in MaximDL.
Again, as Gendler notes, this is a somewhat better way to use the contrast of the H-alpha image (ionized hydrogen compromises a
narrow width of the red band) while better preserving the actual color of the image (the previous image of the Horsehead
Nebula required a great deal of re-colorizing in Photoshop because of the washed out effect on the red channel when using
the Ha image in the L channel.. Imaged with an SBIG STL-11000, using the Tak-106 with Paramount ME. Imaging
performed with John Smith's CCDAutoPilot, using CCDSoft for camera control (-15 deg C), with 6 separate sets of 2x2 binned
10 minute H-alpha, R,G, and B images (20 darkframes assembled for reduction).(KBQ, 11/08/04).
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M81 and M82
in Ursa Major. Imaged with an SBIG STL-11000, using a Tak-106 FSQ
with Paramount ME. Imaging performed with John Smith's CCDAutoPilot, using CCDSoft for camera control (-20 deg C), with 9
separate sets of 1x1 binned 10 minute Clear, and 9 separate 10 min 2x2 binned R,G, and B images (20 darkframes assembled
for reduction for both 1x1 and 2x2 images).(KBQ, Jan 27, 2005). Note: The outside temperature
was -25 degrees Celsius. A Kendrick dew zapper was needed to mitigate lense pinching and image distortion. A very
slight remant of this is still visable. More vigorous use of the heating elements will likely completely reverse this
problem. I have only seen this at about -20 degrees Celsius or below (there are no ways to manually adjust the Takahashi
106 FSQ (ie, no user set screws, as are present on some Borg and astroPhysics refractors. Fortunately we believe the heating
elements will keep the aluminum OTA from pinching the lense. The optics and focusing mechanics of the Tak are so good
that it is hard, but not impossible, to complain about this problem.
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This is yet another variation of
the previous image. Again, the H-alpha and Red channels were processed under Pixel Math in Maxim DL (80% Red and 20%
H-alpha). What's different is the image was less aggressively processed with Adobe CS. Also, the histogram tool
(levels) in Adobe CS was used, in addition to the "curves" tool. The idea was to keep the image from oversaturating,
hopefully giving it a somewhat more "realistic" look (ie, less of an "over-processed" look). The combined Ha/Red image
was used as an enhanced Luminescent (30%) with standard R,G and B channels. Imaged with an SBIG STL-11000,
using a Tak-106 FSQ with Paramount ME. Imaging performed with John Smith's CCDAutoPilot, using CCDSoft for camera
control (-20 deg C), with 12 separate sets of 1x1 binned 10 minute H-alpha, and 12 separate 10 min 2x2 binned
R,G, and B images (20 darkframes assembled for reduction for both 1x1 and 2x2 images).(KBQ, 1/30/05). Note: The key point here is that it is easy to over process an image.
In fact, it is difficult to resisit the temptation to do so. A good trick I got from John Smith is to use the Adobe
CS eye dropper tool and make sure you are NOT oversaturating any part of the image as you process it. Also, the histogram
(levels) tool in Adobe is great for bringing out the mid-range light (grey-zone arrow), while avoiding oversaturation of the
brighter areas (far right arrow of the levels tool).
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Flaming Star Nebula (IC 405) and associated emission nebula
and open star cluster IC 410 (bottom left). Processed using Gendler's technique of layering the Ha (75%) and Red (25%)
images as an enhanced red image (in Photoshop). The combined Ha/Red image was used both as an enhanced red channel and
as a 30% Luminescence channel. Imaged with an SBIG STL-11000, using a Tak-106 FSQ with Paramount ME. Imaging
performed with John Smith's CCDAutoPilot, using CCDSoft for camera control (-20 deg C), with 9 separate sets of 1x1
binned 10 minute H-alpha, and 9 separate 10 min 2x2 binned R,G, and B images (20 darkframes assembled for reduction for both
1x1 and 2x2 images).(KBQ, 12/04). Note: Image is grainy due to a unrecoverable processing
error with Mira (user error, not program error!!) while doing dark subtractions. Proper calibration (dark subtraction,
flat frames, registration) are critical if one wishes to optimize the signal to noise ratio.
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Rosette Nebula (NGC 2337-2339) in Monceros, 4900 light years distant.
An emmission nebula with a number of associated open star clusters, including NGC 2244, within the center. Processed
using a variation of Gendler's technique, layering the Ha (80%) and Red (25%) images as an enhanced Luminescent image
(in Photoshop). The combined Ha/Red image was used both as an enhanced Luminescent (30%) with standard R,G and B
channels. Imaged with an SBIG STL-11000, using a Tak-106 FSQ with Paramount ME. Imaging performed with John
Smith's CCDAutoPilot, using CCDSoft for camera control (-20 deg C), with 12 separate sets of 1x1 binned 10 minute
H-alpha, and 12 separate 10 min 2x2 binned R,G, and B images (20 darkframes assembled for reduction for both 1x1 and
2x2 images).(KBQ, 1/30/05). Note: Learned of a major error afffectng ALL
the previous images. I was using Adobe's Image/Resize Image in order to change the print size to 6x4 inches (ie, keep
it on the page). I was then using the "resample image" option, which caused SEVERE pixilation on zooming in. Now
I change the "document size" but I DON'T "Resample". Usually I end up with a 4008 x 2672 pixel image which has
a document size oof 6x4 and a resolution of 668 pixels/inch.
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Cone Nebula in Monceros.
This nebula is in the southern part of the open star cluster NGC 2264 (Christmas Tree Cluster). Processed using a layered
Ha (20%) and Red (80%) image as an enhanced Luminescent image (in Photoshop). The combined Ha/Red image was used both
as an enhanced Luminescent (30%) with standard R,G and B channels. Imaged with an SBIG STL-11000, using a
Tak-106 FSQ with Paramount ME. Imaging performed with John Smith's CCDAutoPilot, using CCDSoft for camera control (-20
deg C), with 12 separate sets of 1x1 binned 10 minute H-alpha, and 12 separate 10 min 2x2 binned R,G, and B
images (20 darkframes assembled for reduction for both 1x1 and 2x2 images).(KBQ, 2/20/05). Note: The layering technique can be used in a variety of ways. In this case the Ha channel makes
up only 20% of the L channel, giving the stars a more natural appearance, while preserving the ability of the H-alpha channel
to "bring out" some of the details within the nebula. A better process image will be forthcoming.
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As promised, the same nebula with better calibration.
Flaming Star Nebula (IC 405) and associated emission nebula and open star cluster IC 410 (bottom left). Processed as an Ha(100%)RGB
image with Maim DL Digital Development and Adobe Photoshop. Imaged with an SBIG STL-11000, using a Tak-106 FSQ
with Paramount ME. Imaging performed with John Smith's CCDAutoPilot, using CCDSoft for camera control (-20 deg C), with 9
separate sets of 1x1 binned 10 minute H-alpha, and 9 separate 10 min 2x2 binned R,G, and B images (20 darkframes assembled
for reduction for both 1x1 and 2x2 images).(KBQ, 01/01/05). Note: Somewhat less grainy
than the previous image. Calibration with Mira AP, this time without any overt errors on the users part. Compared
to the previous image the stars are much more rounded and there is less "grain" in the image. The next rendition will
utilized Gendler's technique of Ha and Red channel mixing. Pixilation is an issue and will be discussed with Rosette
nebula image.
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This is a variation of the previous
image. Here, the H-alpha and Red channels were processed under Pixel Math in Maxim DL (20% Red and 20% H-alpha).
The concept comes from John Smith. It results in stars with a less mottled appearance then the provious image.
These stars pixilate a bit more, and would likely benefit from a more expert image processer. The combined Ha/Red image
was used as an enhanced Luminescent (30%) with standard R,G and B channels. Imaged with an SBIG STL-11000,
using a Tak-106 FSQ with Paramount ME. Imaging performed with John Smith's CCDAutoPilot, using CCDSoft for camera
control (-20 deg C), with 12 separate sets of 1x1 binned 10 minute H-alpha, and 12 separate 10 min 2x2 binned
R,G, and B images (20 darkframes assembled for reduction for both 1x1 and 2x2 images).(KBQ, 1/30/05). Note: The key points from my perspective are: 1) Processsing H-alpha
(or other narrow-band filter) enhanced images is challenging. There are many ways to process the data, each with it's
own strengths and weaknesses. and 2) Maxim DL has many useful features, such as Pixel Math combining (as noted above)
which are not available in an equivilent form in Adobe CS (which is, of course, an amazingly powerful program in it's own
right).
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