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sophiecentaur
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I’ve considered it. Now what?chemisttree said:
I’ve considered it. Now what?chemisttree said:
I don’t think phase contrast will work on the sun. A filter would be required. The phased image would be completely blocked out.chemisttree said:
How could phase contrast be applied to an object the size of the sun? Could you provide a diagram?Quarker said:I don’t think phase contrast will work on the sun. A filter would be required. The phased image would be completely blocked out.
It would work like any other telescope of similar size and f ratio. The only difference would be the additional phased image provided by the eyepiece. As I said earlier, there are aberrations inherent in the design of eyepieces that could be phased with only minor adjustments. The problem is, no such eyepiece is being made.sophiecentaur said:How could phase contrast be applied to an object the size of the sun? Could you provide a diagram?
Why would it not work for the Sun, but work for a nebula or other deep sky object?Quarker said:I don’t think phase contrast will work on the sun. A filter would be required. The phased image would be completely blocked out.
I’m probably missing something but could you actually indulge me with a diagram showing how the “phasing” takes place and what the result would be on a solar image [Edit: or any astronomical image]?Quarker said:It would work like any other telescope of similar size and f ratio. The only difference would be the additional phased image provided by the eyepiece. As I said earlier, there are aberrations inherent in the design of eyepieces that could be phased with only minor adjustments. The problem is, no such eyepiece is being made.
Drakkith said:Why would it not work for the Sun, but work for a nebula or other deep sky object?
If anyone ever tried to design a phase contrast telescope by adding a phased image to the visual image, they would have had a problem combining the two images. The eye will simply ignore the phased image in favor of the visual image. I think this problem can be solved by using a slow telescope with a wide depth of focus. If the eye can be held within the depth of focus above the eyepiece, the visual and phased images will align perfectly with one another. When the visual image is focused, this will hopefully force the eye to detect the phased image as well. Basic physics says that the amplitude of the visual image should double at that point. What that means visually is still an open question. But if dim objects like galaxies can suddenly become visible using a simple property of light, it seems worth it to me.sophiecentaur said:I’m probably missing something but could you actually indulge me with a diagram showing how the “phasing” takes place and what the result would be on a solar image [Edit: or any astronomical image]?
I can appreciate that lenses can be designed to produce ‘sharpening’ at the expense of added diffraction effects and resolution. But is that Phase Contrast?
I have already made the point that the evidence is a present lack of such an attractive Astro tool. Amateur astronomers are all desperate to spend their money and the industry would have produced thousands of PC eyepieces if there were even cat’s chance of having possible models available.
I wish I could provide a detailed ray diagram showing exactly what I’m talking about when I refer to depth of focus, but they seem to have disappeared from the internet. All I can find are simplistic sketches of undergrad homework assignments.sophiecentaur said:I’m probably missing something but could you actually indulge me with a diagram showing how the “phasing” takes place and what the result would be on a solar image [Edit: or any astronomical image]?
I can appreciate that lenses can be designed to produce ‘sharpening’ at the expense of added diffraction effects and resolution. But is that Phase Contrast?
I have already made the point that the evidence is a present lack of such an attractive Astro tool. Amateur astronomers are all desperate to spend their money and the industry would have produced thousands of PC eyepieces if there were even cat’s chance of having possible models available.
Quarker said:The phased image will probably not be very bright to begin with.
Yet again, you haven't actually described what you mean by "phased image" or even the basics of how your eyepiece could work. I don't need a 'detailed' diagram- just something that tells us what you have in mind.Quarker said:I wish I could provide a detailed ray diagram showing exactly what I’m talking about when I refer to depth of focus
Of course, and so do we all but you can't just hope your idea will work without good cause.Quarker said:I simply want to make dim images more visible.
You have to realize that every part of the normal image, formed by a lens is, in fact due to constructive interference of light taking all the alternative paths from object to image. In the case of an astronomical telescope, you want as much light to land in the appropriate place. That's the best you can do.Quarker said:As to the source of the constructive interference, I’ve been as specific as I can be for a non-optician.
As a non-optician you should realize your limitations and treat the subject seriously. "If' doesn't make devices work; knowledge sometimes does. Give the subject some respect.Quarker said:I’ve been as specific as I can be for a non-optician.
I've already explained that this isn't possible. If you want to make it brighter you either get a bigger aperture or you reduce the focal ratio. The latter of which only works because you're making the image smaller, cramming the same light into a smaller area.Quarker said:I want to use constructive interference to increase the amplitude of the light coming from a dim source like a face-on galaxy. This should, theoretically, make the image easier to see.