10/28/2006 
Imaged some stuff with the ST2000XCM and E-finder combo. For guiding I rigged the Meade 1040 SCT with f/6.5 compressor and the SBIG ST-402 combo. It is a rock solid guide system now that it has a 4 watt heating strip and due shield. 2 second exposures fill the selection screen with guide stars.
Before I spend the money on 35mm type camera lenses and adapters, I wanted to see how the FR-237 ( E-finder ) lens did on extended objects like NGC7000 or M31. At a fixed focal length of 100mm f/4 it did pretty well. M31 can be seen to the right. It is to big to fit in the non smeared area, but not bad for a 1" lens. I am amazed that 4 hrs of 10 min subs can be processed and combined in 30 minutes of work. The center of the field is almost acceptable but the edges are pretty bad. The image ( far right ) is made of 24 x 10 min subs ( 4 hrs color data ) at about 100mm FL. These are the best frames from 6 hrs of data.
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10/11/2006 
I am told that an f/1.1 RC mirror is a tricky thing to work on. I have graciously agreed to give Mike a few extra days to get it done. To keep in imaging practice I have been using the Vidicon lens and ST2000XCM camera combo. For guiding, the Meade 1040 SCT / SBIG ST-402 combo seem to be a good match. Guiding at 1040mm focal length and imaging at 100mm FL really makes the stars stand still. Even with the FR-237 removed, there are still tons of guide stars to chose from in any field.
I wanted to see how the Vidicon lens did on extended objects like NGC7000 or M31. As the magnification increased it became apparent that the lens was being pushed far past its capabilities. The center of the field is almost acceptable. but the edges are pretty bad. The image ( far left ) is made of 24 x 10 min subs ( 4 hrs color data ) at about 120mm FL. These are the best frames from 12 hrs of data.
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08/31/2006 
The 28" primary mirror is summering in Illinois and getting buff. While it is gone, I have time to test and modify all sorts of stuff on the mount and camera. I put the structural pathfinder frame into the telescope cradle so that I could hook back up the DEC drive. I am still in Dan Gray's alpha test loop for the Sidereal Technology Servo drive system so as new revs of the driver come out, I have been trying them out. I managed to rig up an old Meade 1040 SCT to the SBIG ST-402 and now have a sweet autoguider. With the little telecompressor installed ( FR-237 ) there is 500mm of focal length and always a few guide stars to choose from.
I also rigged up an old Vidicon 260mm to16mm telephoto lens to an ST2000-XCM. At 16mm and f/5.4 it makes one sweet all sky camera. I tried using the XCM camera for color data on my DSO's but did not like the results. As an all sky color camera it simply rocks. The image seen is a single 1 minute exposure with a little processing to enhance the color in Photoshop CS. I took 120 of them and made a little movie that shows some nearby tree tops sneaking up and eventually eating the Milky Way galaxy. I had no idea that trees were star-nivorous. This lens was an old ex-USAF ( long since out of fashion ) 4" TV camera lens that I had to create the C-mount to 48mm threaded interface for. It has serious coma towards the edges of the chip, but what the hay, I got 10 bucks in the glass. :_)))))
My primary mirror is not due back for few months so I may have to amuse myself with this little poor boy's all sky camera till Orion once again graces the evening sky.
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06/23/2006 
The 28" RC has been in pre-teardown testing for a month now. I am getting ready to have the primary mirror re-figured so I wanted to record the current capabilities. The Ronchi test image ( right ) is from a a home-made adapter I made for the ST8i camera. It uses a little loop lens to image a 120 lines per inch screen located about an inch away from it directly onto the CCD detector. I can adjust the focus of the loop so the lines are sharp and straight with a white light test source. In this testing, the star is 6 th mag and light up the grid nicely. I put in a 2.5" extension barrel so that the screen is at the same focal point as the CCD usually sits at. The camera is 2.5" farther away but that is not important to the optical test. The number of lines seen is varied from about 10 to 1 to 10 as I focused from intra-focal thru focus to extra-focal.
Using a new alignment process I worked out for the secondary mirror, I have reduced the mis-alignment induced distortions quite a bit. I had about 50 minutes of M-13 imaged but seem to have lost it.
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05/05/2006 
Reconfiguring the mirrors to put the secondary 22" away from the primary and adding masking to reduce the primary to 24" yielded this set of M66 data. Compiled over 5 nights the LUM is the best 3 hours ( of 6) and the color is 1 hr each RGB. Field of view is 10 x 15 arcmin, , north is up. The fairly bright star just right and slightly above M66 is 9.8 mag. Limiting mag is about 18 with S/N ratios above 30. This data set has been heavily processed with layer masking and sharpening. All subs were taken at 2x2 bin. The optical issues with the primary mirror are still quite evident as seen by the distorted star shapes.
Exposure : Data : LRGB 3 hr ( 5 min subs )
RGB 1 hr each color ( 5 min subs )
Camera : SBIG ST-8i ( non E ) AGB parallel port version , 9x9 micron pixels, 0.60 arcsec/pixel
Capture software : CCDSoft v5.xx
Processing Software : MAXIM DL / CCD, PS CS v9.xx
Post Processing : Dark subtraction, Combine-sigma clip, PS levels and curves, layer mask sharpening, color combine.
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03/08/2006 
This is another engineering test image from the 0.7 meter f/4.4 RC. The optics are currently masked down to 20" so the effective focal ratio is f/6.5. Field of view is 10 x 15 arcmin, , north is up. The brightest star in the field is 68 delta Leo ( Zosma ) at mag 2.5. Limiting mag is about 18 with S/N ratios above 30. This is a comparison of two processing ideas. The 1x1 Luminance version has smaller stars but does not get anywhere near as deep as the 2x2 Lum version. At 1.2 arcsec per pixel ( binned 2x2 ) the loss in resolution is not worth the 4x exposure time to get the same S/N ratio. The mirrors are very well aligned now and the stress in the secondary holder has been tweaked to create mostly round stars. The auto-guidance system is working ( with bright guide stars ) and so is the tracking. Using THESky 6.xx I can now slew about the sky and place any target on the imaging chip. The number of things wrong with my scope and these images is getting smaller :_))))
Exposure : Data : LRGB 1x5m
CRGB 3x5m
Camera : SBIG ST-8i ( non E ) AGB parallel port version , 9x9 micron pixels, 0.60 arcsec/pixel
Capture software : CCDSoft v5.xx
Processing Software : MAXIM DL / CCD, PS CS v9.xx
Post Processing : Dark subtraction, Combine-sigma clip, DDP, PS levels and curves to bring up the fainter stars and galaxies
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02/22/2006 
This is an engineering test image from the 0.7 meter f/4.4 RC telescope . The optics are currently masked down to 20" so the effective focal ratio is f/6.5. Field of view is 10 x 15 arcmin, , north is up. The brightest star in the field is Zosma (delta Leo) at mag 2.5. Limiting mag is 17.5 with S/N ratios above 30. THESky 6.xx screen shot is included to reference objects in field. Only a few minutes before this image was taken, I had discovered that the secondary holder was under stress due to my design and fabrication. I corrected about half of the problem and decided to take a star test image. Aside from the fact that this star was nearly overhead there is nothing special about it. There is a 16.5 mag star only 42 arcsec from the big one that was clearly captured. Although just a smudge, there is a 17.5 mag galaxy captured also ( mid center of field ).
Exposure : Data : 6x 1m LUM, 1x1 bin
Camera : SBIG ST-8i ( non E ) AGB parallel port version , 9x9 micron pixels, 0.60 arcsec/pixel
Capture software : CCDSoft v5.xx
Processing Software : MAXIM DL / CCD, PS CS v9.xx
Post Processing : Dark subtraction, Combine-sigma clip, PS levels and curves to bring up the fainter stars
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02/06/2006 
This is an engineering test image from the 0.7 meter f/4.4 RC telescope . The optics are currently masked down to 20" so the effective focal ratio is f/6.5. Field of view is 10 x 15 arcmin, , north is up. The brightest star in the field is 48 Auriga at mag 5.0. Limiting mag is 15.5 with S/N ratios above 30. THESky 6.xx screen shot is included to reference objects in field. There is nothing special about this star except it was directly overhead when I needed a test subject for mirror alignment investigation. The mirrors are not correctly aligned yet and there is some kind of stress in the secondary screwing up the image. The number of things wrong with this image is too great to list.
Exposure : Data : 5x1m LUM, 1x1 bin
Camera : SBIG ST-8i ( non E ) AGB parallel port version , 9x9 micron pixels, 0.60 arcsec/pixel
Capture software : CCDSoft v5.xx
Processing Software : MAXIM DL / CCD, PS CS v9.xx
Post Processing : Dark subtraction, Combine-sigma clip, PS levels and curves to bring up the fainter stars
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07//2005 
This is an engineering test image from the 0.7 meter f/4.4 RC telescope . The optics are currently masked down to 25" so the effective focal ratio is f/5.1. There is some kind of astigmatism in the system that is screwing up the image. The star-mirror-grams show that the mirrors are fairly well aligned but there is a warp in there somewhere. The intra-focal and extra-focal images are not even close to being symmetrical. There is a nasty squish to the near focal star images on a 45 degree that seems to flip thru focus. This is classic astigmatism but I don't know where it is coming from. It could be the primary not liking the 9 point floating suspension, but 4" thick glass is pretty sturdy stuff. The secondary could be not liking its suspended mount. It is only 1 inch thick so it may be flexing. It could be that I am missing some critical part of the optical train. It could be any number of things that are too depressing to continue to list.
Exposure : Data : 1 second LUM, 1x1 bin
Camera : SBIG ST-8i ( non E ) AGB parallel port version , 9x9 micron pixels
Capture software : CCDSoft v5.xx
Processing Software : MAXIM DL / CCD, PS CS v9.xx
Post Processing : None