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Everything posted by wisepeter

  1. The price of a Zerochromat 8 inch could be around 8,000 Euros or less, depending on numbers. I have designed the Zerochromat in much larger apertures, and a 12 inch version is not impossible, maybe even a 16 inch. I would probably make it f10, and shorter in relative terms than the 8 inch. However, the 8 inch needs to be established first.
  2. I am going to hand over the scope I am currently finishing off to a recognised astro imager, as this not an area that I am anywhere near expert in! Though I am going to take some images myself before doing that. Please form an orderly queue.............!
  3. Exactly the same principle! There was also the Risley prism which worked in the same way.
  4. Only a small amount of adjustment is needed, at worst about a quarter turn of one of the knobs. Even with an equatorial mount, the adjustment is simple, and if you turn the wrong knob, it is easy to return it to its previous position, and then try a different one. When you turn the correct one, the chromatic aberration magically disappears. Of course, observing near to the horizon is not going to give a very good image anyway, but it is good for demonstrating planets to newcomers when you have no choice as to planetary position.
  5. That is simple - by adjusting the fold flat, errors are introduced to counter atmospheric refraction (as long as you tweak the correct knob!). It is an easy job to then re-adjust for stars or planets higher up. Of course, what you get is not perfect, but a distinct improvement on a bad situation. The result is surprisingly good. The Russian apo system using a single lens is not retro-focal, so is different from the Zerochromat. It also can only be used in small telescopes, as the errors multiply very quickly past 100mm in aperture.
  6. The design has been made to be very tolerant of mis-collimation. It is true that the corrector lenses need to be carefully aligned with regard to each other, but that is a fairly trivial mechanical exercise. As long as the corrector array is then aligned with the focuser tube, the rest is easy. The large fold flat takes care of any small inequalities, and can even take out atmospheric refraction. The main idea is to make a superb planetary/lunar telescope that can take in the smaller DSO's. Although it was designed for visual use, it can also be used for imaging. It is also very lightweight at 10kg, and is the length of an 8 inch f6.5. The price is a moot point, as it depends so much on the numbers! The system has virtually no expansion - I set one up in the Arizona desert on distant mountains during the day, and at night, it needed no focus adjustment on stars.
  7. Not the point. The plain fact is that the precise point at which a product is ready for market cannot be known with any degree of certainty. Until several have been made, you cannot do an analysis. Why do you think that car makers have to do recalls? None of us wants to get it wrong, but even multi-million pound enterprises make mistakes. For those people that have never invented anything, it is only too easy to criticise. There are very few people with the foresight, sheer guts and persistence to attempt something completely new, but a huge number just waiting to pick fault.
  8. Not quite right - the Zerochromat had been tested by Dave Tyler, plus my own testing showed that the optics are very good. I have not followed the design up for quite a while because of other projects, but now have the time to do so. It is quite common for designers to put products on the market at an early stage - even large concerns such as car makers etc have put products on the market which are not really ready for sale. Early Sierra cars were awful! Also the early Celestron telescopes had all sorts of problems, which took a while to sort out.
  9. Hi everyone, the 'Newise' design is actually an extremely good one, as evidenced by those who own and use one. Sadly, it was killed off by poor quality control of Chinese optics - we ordered 100 sets of optics, paid up front, and had to reject 96 of the front widows due to astigmatism. Having nothing to sell, and no funds to sort out the window nightmare, I had no choice but to wind the company up. The patent is still in effect, so maybe one day it will be resurrected. The Zerochromat is not 'vapourware', but may take a little more time before it sees the light of day commercially. Collimation is much much easier than you would think. Dave Tyler has had access to an early version, as has Martin Taylor. If you watch this space, an upgraded (prettier!) prototype will be appearing in March this year. The theoretical Strehl ratio is 0.995 across the visual range, so stars look textbook perfect. One reviewer even complained that the diffraction rings at high powers are very weak compared to the Airy disc, and thought that that reflected some sort of optical defect. 'Nuff said......
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