Yep field de-rotators are an option. Sometimes the right option, but they are an added drive system and can be pesky. I would say in this case a much better option than trying to build an equatorial mount for an instrument this large.
No not really the same thing at all. Both strategies will form an image but the physics are different. The mirror reflects the light via a paraboloid and thus forms the image without any chromatic abberation. For the lens to form an image the light must pass through the glass and because the speed of light in the glass depends on the wavelenght, the refractive index is slightly different for every wavelenght and the therefore the lens will show significant chromatic abberation. This is assuming that it is a single lens. Multiple element lens are possible to design with different refractive indicies that will minimize this effect but they are much more complex and expensive. Oh by the way the largest refractor ever built is the Yerkes telescope which is only 40" in diameter. Anything larger would distort under it's own weight.
Even with tracking capability, which isn't that hard for a dobsonion, alta-azimuth mounts like this suffer from field rotation effects and exposures longer than about 30 seconds are not ideal. But you can take many 30 second exposures and stack them to give you something resembling a much longer exposure. The stacking de-rotates the images and aligns them.
I can back up your calculations. Did mine in Ohio and came up with about the same results. Large out of pocket expense for about 1/3 of my usage. Then no guaranteed subsidy as they would be so called market priced in the future and may be phased out. Decided to let the greenies invest. Oh also while the panel prices have become cheaper, have you priced the mounting brackets lately? Extremely high prices for these at about half the price of the panels.
Me Too. Anything less than 10 hours and it is not worth it to fly. Plus I can leave whenever the mood strikes me instead of waiting around in the hotel room until it is time to leave for the airport.
It is also possible that Joe Salesdroid recogonized a need and sold a product that had value for that customer. Now i agree he should have consulted with the dev team, but a sale that causes inconvience is far better than no sale at all.
Bzzz't not really. I can live with a ding in my trunk lid. The car will not notice and perform flawlessly. But with a battery trunk lid, I just lost 20 percent of my energy capacity until I make a very expensive repair.
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You can get chicks with titles. Wow what was I thinking?
Yep field de-rotators are an option. Sometimes the right option, but they are an added drive system and can be pesky. I would say in this case a much better option than trying to build an equatorial mount for an instrument this large.
Mine also gets the 26 mpg up to about 80 mph. Afraid to average more than this for long stretches due to the high cost of citations.
No not really the same thing at all. Both strategies will form an image but the physics are different. The mirror reflects the light via a paraboloid and thus forms the image without any chromatic abberation. For the lens to form an image the light must pass through the glass and because the speed of light in the glass depends on the wavelenght, the refractive index is slightly different for every wavelenght and the therefore the lens will show significant chromatic abberation. This is assuming that it is a single lens. Multiple element lens are possible to design with different refractive indicies that will minimize this effect but they are much more complex and expensive. Oh by the way the largest refractor ever built is the Yerkes telescope which is only 40" in diameter. Anything larger would distort under it's own weight.
Even with tracking capability, which isn't that hard for a dobsonion, alta-azimuth mounts like this suffer from field rotation effects and exposures longer than about 30 seconds are not ideal. But you can take many 30 second exposures and stack them to give you something resembling a much longer exposure. The stacking de-rotates the images and aligns them.
I can back up your calculations. Did mine in Ohio and came up with about the same results. Large out of pocket expense for about 1/3 of my usage. Then no guaranteed subsidy as they would be so called market priced in the future and may be phased out. Decided to let the greenies invest. Oh also while the panel prices have become cheaper, have you priced the mounting brackets lately? Extremely high prices for these at about half the price of the panels.
Wait a minute, I thought that Putin designed it and coded it all in a weekend while entertaining ladies.
Unless of course someone comes up with 6 minute abs.
Me Too. Anything less than 10 hours and it is not worth it to fly. Plus I can leave whenever the mood strikes me instead of waiting around in the hotel room until it is time to leave for the airport.
It is also possible that Joe Salesdroid recogonized a need and sold a product that had value for that customer. Now i agree he should have consulted with the dev team, but a sale that causes inconvience is far better than no sale at all.
Bzzz't not really. I can live with a ding in my trunk lid. The car will not notice and perform flawlessly. But with a battery trunk lid, I just lost 20 percent of my energy capacity until I make a very expensive repair.