ariesram

well, I think what matter more than weight is the torque. But how to calculate torque for a specific telescope?

Hello there, Having imaged successfully with 200mm telephoto lense on Vixen Polarie, I am eyeing on a Vixen polarie accessory on vixen website. ITEM #35529C - HEAVY LOADING KIT FOR POLARIE This kit has everything you need to start imaging at high magnification with the use of a heavier camera or small telescope. Anyone has the kit and tried small telescope on it? Any idea what small telescope can be mounted on it for astrophotography? I own an Orion ED80 which is weighted 5.7 lbs and 600mm focal length. Thanks

I am trying to figure out how accurate polar alignment should be in order to get a round star photo using certain lens and exposure time. calculated pixel size is about 15 arcsecs per pixel using my DSLR with 70mm lens on this website. https://starizona.com/tutorial/pixel-resolution-and-field-of-view-calculator/ Calculated alignment error using this tool. http://celestialwonders.com/tools/polarErrorCalc.html Input drift 15 arcsecs, 1 minute, and declination 35 degrees, calculated alignment error is 69.95 arcmins, more than 1 degree. It is an error tolerance that allows rough polar alignment, isn't it? As long as Polaris is close to the mark that it is supposed to, there should be no trailing. I used this method to do polar alignment. Then verified the position of the 6 clock mark using PS align Pro. https://fstop138.berrange.com/2018/05/polar-alignment-of-the-skywatcher-star-adventurer/ I tested more than 10 times in different locations, and got good round stars 3 times using my Star Adventurer. All of rest is trailing ones. I could get round stars in one exposure, and all the following exposures are trailing stars. Polar alignment is as accurate as possible. I am sure that it's on Polaris, not other stars. No wind, solid Gitzo series 3 tripod on solid surface, shutter cable and remote control. Camera on DEC plate, no ball head. Properly balanced. I calibrated polar scope as per the process on the manual. It is good, too. I did a 24 hour test indoor. I marked a laser point on the wall 21'5" from the SA. 23 hour 56 minutes later the laser point was only 1 3/8" away. this is about 0.3 degree. 0.0002 degree per minute. Also I did a long exposure test of lights on horizon far away. No periodic error, no zigzag line of the lights. What can be wrong with the process? Does it tell that the SA is defect? Thank you

Hi there, I purchased Star Adventurer a few months ago and tried it really hard more than 10 times. It never worked - 30 second exposure shows trailing. Polar alignment is very good, from what I can see. All screws are tightened, camera and lens are under 5 lbs weight, attached directly to DEC plate without ball head. I believe for sure it is the star adventurer malfunctioning. How can we verify star adventurer is tracking correctly? Is there any tests we can run to confirm it is functioning as expected? Thanks,