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About michael8554

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  1. michael8554

    Motion of telescope on a wedge

    The Celestron deluxe Tele Extender allows you to do high magnification eyepiece projection imaging, which I assume means you want to do planetary imaging. In that case the mount should track a planet for short video sequences without a wedge. If however you are considering Deep Space Objects, the single fork 8SE isn't robust enough for serious long exposure imaging IMO. Also you would probably not need the eyepiece projection, more likely the other way with magnification ie a Reducer. Michael
  2. michael8554

    Imaging through IR light.

    If your camera has an IR cut filter I believe you'll be alright? Michael
  3. michael8554

    Canon D450 drivers

    I have a Windows 7 Home Premium 64bit Desktop PC and I have just tried a 450D on it. Runs Canon Utilities just fine, the remote controller operates the shutter and downloads images to the PC and ZoomBrowser EX displays the image. Michael
  4. michael8554

    Dithering with 1000D-scale setting

    Yes 5.95/0.76, my bad Michael
  5. So true Pete. But maybe there are tweaks in the DIGIC processing of Raw images that will be upset by the removal of the LPF-1 filter? Relax, just being provocative, the only downside I've heard of is infrared star bloat with refractors Michael
  6. Variously branded as GSO, Altair Astro, Revelation, Bresser etc. Needs to give zero (or minor) focal length change. Thanks Michael
  7. michael8554

    Dithering with 1000D-scale setting

    Well the guide scale (3.75um pixels and 130mm FL) is 5.95arc secs per pixel Imaging scale with 200P/200PDS (1000mm) and 1000D (5.7um pixels) is 1.18arc secs per pixel So every one pixel movement from the guidecam will move the DSLR 5.95/1.18 = 5 pixels approx (So to guide to less than one pixel imaging accuracy you need PHD2's sub pixel guiding ability) So a multiplier value of 2 in PHD2 would give you a dither of about 10 pixels. For the 127 Mak (1540mm) it's 0.76 arcsecs per pixel This time the ratio is 1.18/0.76 = 1.6 pixels approx. So a value of 6 would give you a Dither of about 10 pixels. Calculator here: https://astronomy.tools/calculators/ccd Hope I've got my ratios the right way round !! ............ :-> Michael
  8. michael8554

    Dithering with 1000D-scale setting

    The dither scales in PHD2 set the number of guide camera pixels the mount is dithered, not the imaging camera. So you need to work out the ratio, guide arcsecs per pixel to imager arcsecs per pixel. This figure will be unique for each setup, so only saying you have a 1000D won't work. So if your ratio is 3 and you want to dither the imager 12 pixels you would set PHD2 to dither 12/3 = 4 pixels. Michael
  9. Yes Tris, the standard wedge is a POS. Tightening usually changes the alignment because the wedge bends so easily, so you have to learn to under adjust so that tightening gets you on the mark. Pier mounted and well drift aligned, I have never bothered with 1 or 2 Star alignments, I just SYNCH on a star near the DSO. Michael
  10. michael8554

    Mead LX 200 needs repair

    I think the troubles started when Meade upped the psu volts from 12 to 18v without upgrading the C's. Repair it and stick to 12v. Michael
  11. michael8554

    Canon EOS 6D PC recognition

    I have a 6D mk1 Win7 Home Premium 64 bit Connects to Canon Utilities and a Shutter Counter no problem. Michael
  12. michael8554

    Preserving Autofocus on Modded DSLR's

    My previous camera was a 500d. I too had it modded by Juan, because of the floating sensor. But my current camera is a 6D that nobody wants to modify, only to sell ready modded. I've already modded one high shutter count 6D, but I now want to do a newer one. The Autofocus is actually no big deal for my solely telescope needs, but would be a bonus in any future sale. Michael
  13. michael8554

    Wooden pier

    Not to be pedantic, but to get the length of bolts you need it's easier to get stainless studding, Use big washers through pairs of posts, then join those two pairs together with more staggered studding. No way of knowing if one big post would move more or less than four smaller posts with the end grains randomised. Michael
  14. michael8554

    Wooden pier

    Since I installed my wood pier in 2015 I have seen a product called Postsaver used to protect farmer's wooden fence posts. I only saw them when they were installed, I'd guess they are placed over the end of the post then heat-shrunk, I could see the section above ground. Michael
  15. I believe that Canon DSLR models starting with the 500D now have floating spring-loaded imaging sensors, adjusted by Torx headed screws. Here are my (untried) calculations for adjusting the sensor to preserve Autofocus after LPF Filter removal. Gary Honis gives superb instructions for modding almost every Canon DSLR at http://dslrmodifications.com/ Each LPF filter refracts the light passing through it, which extends the light path. So without a LPF filter the sensor has to be screwed in further towards the shutter to meet the autofocused image. Gary's calculation for the correction figure is based on a Refractive Index of 1.517 for the LPF: (0.517 x Thickness of Removed Filter) ÷ 1.517 = Correction in mm I understand the LPF#2 filter on the floating sensor models are 0.5mm thick, but that can be checked with a micrometer. So for a LPF#2 removal, retaining the LPF#1 filter, the correction figure is: 0.517 x 0.50 ÷ 1.517 = 0.17mm I also understand the Torx T7 screws are M1.6 x 0.5mm pitch. To check, measure the length of 10 threads with a micrometer and divide by 10 to give the pitch. 0.5mm pitch means each full turn moves the screw 0.5mm in or out. Gary's method of adjustment uses "points". He notes that the star-shaped sockets of Torx screws have 12 "points". So before unscrewing the Torx screws he makes a radial Sharpie mark on each Torx screw head and the sensor mount. So on replacement, the Torx screws should be returned to the Factory "height", at which point the Sharpie marks should align. The final adjustment for 0.17mm Autofocus Correction is: 12 (points) ÷ 0.5 (pitch) x 0.17mm = 4.08 "points" (4.08/12ths of a turn). So the Torx screws are tightened a further 4 "points" to preserve Autofocus. I hope someone can confirm or refute these calculations before I get going on a mod !! Michael

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