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Fill the Big Brain

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  • HumanoidoHumanoido Posts: 5,770
    edited 2011-11-06 23:15
    Build This "Million Drops" Liquid Telescope
    Runs on Water Fuel

    Million water drops telescope

    The fuel to power this telescope comes from water and forms the primary Plano-Convex lens for this refracting design. It can build in versions ranging from small lenses on up to giant lenses. The upper limit is imposed by the weight of the lens and the strength of the membrane.

    attachment.php?attachmentid=86645&d=1320648142
    The Water Drop Telescope forms varying size refracting
    lenses by a clear transparent membrane and a million
    drops of water.

    ______________________________


    Telescope Key
    1 - Plano surface (flat) of water level
    2 - Mount
    3 - Water
    4 - Clear Plastic Membrane
    5 - Detector
    6 - Lower Mounting Surface

    Assembly
    1) Begin assembly with the side mounts (2)
    2) Stretch a strong yet very clear membrane across the top of the mount (4)
    3) Add water (3)
    4) Take some photos with camera (5)

    Theory of Operation
    The weight of water held in place by the sagging membrane and pulled down by gravity will form a spherical convex surface. Parallel celestial light rays enter through the plano side of the lens and exit the convex side, converging to a common focal point where a detector measures and records the image.

    Materials
    Go to the kitchen and find the Seran Wrap. This will make a lens about a foot in diameter. For larger lenses, use industrial clear wrap. Try large sheets of commercial shrink wrap and clear rolls of cellophane in 12-foot wide rolls. This will make a telescope with a refracting objective as large as 144-inches in diameter. Make sure the material is strong enough to support the weight of water.

    Weight of Water
    Water weighs about 8.328676 pounds per gallon and is dependent on slight variations due to temperature and pressure.
    http://mathforum.org/library/drmath/view/56355.html

    Weight of Common Water Lenses
    Gallons
    Weight (LBS)
    001
    8
    002
    17
    003
    25
    004
    33
    005
    42
    006
    50
    007
    58
    008
    67
    009
    75
    010
    83
    020
    167
    050
    416
    0100
    833
    0500
    4,164
    1000
    8,329

    Construction Tips
    Use the Weight of Common Water Lenses chart to determine the weight and the practicality of the material to support this weight.

    Weight
    The weight of a million drops water lens is 110 lbs.

    Increasing Strength
    You can increase the strength of the membrane by doubling up on the surface layer but this will also degrade optical viewing by a certain proportional amount. The degree of degradation may be well worth it to massively increase the diameter to gather more light.

    Adjusting the Telescope
    Some membrane stretch may occur. This is offset using a detector with travel focus.
    366 x 352 - 24K
  • HumanoidoHumanoido Posts: 5,770
    edited 2011-11-06 23:35
    Rating a Water Drop Telescope

    Choose the size of your water drop telescope by the number of water drops.

    We are now using this new water drop converter
    http://www.conversion-metric.org/volume_conversion/drop_to_gallon_conversion.php

    1000 Drop = 0.0171321916083 Gallon

    (to be continued)
  • ElectricAyeElectricAye Posts: 4,561
    edited 2011-11-07 06:33
    Humanoido wrote: »
    ...

    Filtering
    Filter out achromatic aberrations etc. with a glass filter.....

    I think the only way this approach would improve your image quality is if it filtered out all wavelengths but one.


    Humanoido wrote: »
    ...

    The fuel to power this telescope comes from water and forms the primary Plano-Convex lens for this refracting design. It can build in versions ranging from small lenses on up to giant lenses. The upper limit is imposed by the weight of the lens and the strength of the membrane.....

    Have you actually cranked the math to see what sort of shape such a loaded membrane might provide? Be aware that a real-world membrane would have slightly more elasticity, etc. in some places than in others, and those polymer properties will differ according to orientation, strains, etc., so the actual curve the water bag creates would most likely be optically impaired. Even local variations in the bag thickness would matter in this case. I think one point you consistently forget in your designs is this: good optical imaging systems need to be made to tolerances on the order of 10's of nanometers, mere fractions of a wavelength of light. Otherwise, the best you can hope for is some kind of light bucket, good maybe for solar energy applications, but not for imaging much. You seem determined to push some sort of frontier by making things bigger, more complex, more involved (dare I say grandiose?) than anything that has ever come before, but it seems to me that most inventors and pioneers push for simplicity and elegance. I'm sure you could apply your Big Brain to adaptive optics or large telescope manufacture or something like that, but you really need to kick back a bit, take a deep breath, read a couple books on optics, and start simple before you hit the launch button.
  • HumanoidoHumanoido Posts: 5,770
    edited 2011-11-07 11:20
    I think the only way this approach would improve your image quality is if it filtered out all wavelengths but one.

    it could be just the opposite! You want to keep all optical wavelengths and filter out just the achromatism. Since achromatism varies from optics set to optic set, telescope to telescope, it helps to tune directly to a particular optics.

    The big low cost glass that we're experimenting with does not have canceling combinations of crown and flint (if it did it would cost thousands of dollars), which is very acceptable for the current low cost project.

    But your way will work too. Optically view in the wavelength of green light for example and we have two solutions to one challenge.
  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2011-11-07 11:32
    Humanoido wrote:
    You want to keep all optical wavelengths and filter out just the achromatism.
    And what kind of magical filter do you propose for such a purpose? Achromatism manifests itself as image blur for all but the wavelength to which a non-color-corrected lens is focused. How do you plan to: 1) Separate the blurred parts of the image from the in-focus part, and 2) refocus the blurred parts?

    When the Hubble Space Telescope was launched, it was out of focus, due to some mistaken calibration during manufacture. No amount of software massaging can fully repair a blurry image. It was not until corrective optics were installed that we were able to enjoy the stellar images of which it is capable.

    -Phil
  • HumanoidoHumanoido Posts: 5,770
    edited 2011-11-07 11:32
    Really the projects are quite simple. Even the Big Brain operates on some fundamental rules.

    But you're right about my go-for-it attitude when it comes to big telescopes. I love big telescopes. In my career as professional astronomer, I built and worked with some of the biggest telescopes in the world. Indeed, I admit it - I have aperture fever, and continue to need larger and larger telescopes...

    You really need to look through a good telescope to get hooked. I really encourage you to seek out the local astronomy club and attend their next star party. Aperture fever is very catching.

    Now I'm finding new ways to simplify making large telescopes and to bring down the cost to make it affordable to the amateur scientist. After you get aperture fever, you will appreciate this more. :)
  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2011-11-07 11:43
    Humanoido wrote:
    Now I'm finding new ways to simplify making large telescopes and to bring down the cost to make it affordable to the amateur scientist. After you get aperture fever, you will appreciate this more.
    Aperture fever is probably counter-productive for most amateur astronomers. One of my biggest mistakes in life was spending thousands on an 11" Schmidt-Cassegrain scope. It's a beautiful scope with a rock-solid equatorial mount. But it takes forever to lug outdoors and set up. And you know what? I haven't used it in years. Moreover, scopes with large apertures are more susceptible to atmospheric turbulence than are smaller scopes. Also, SG scopes exhibit poor contrast compared to their achromatic refractive bretheren. I would have been much better off with a 4-5" apochromat. The best telescope for any amateur's needs is one that they will use.

    -Phil
  • HumanoidoHumanoido Posts: 5,770
    edited 2011-11-07 11:44
    To a lay person, it does seem like a magical filter.
  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2011-11-07 12:01
    Well, for us lay people in the forum, perhaps you can describe how it works. Be sure to use short words and simple sentences. I'm often baffled by complex subject matter.

    -Phil
  • HumanoidoHumanoido Posts: 5,770
    edited 2011-11-07 12:09
    Phil is negative about everything. If he didn't like hauling around a small 11-inch SCT he could build a nice observatory and the telescope would be ready at all times. (I'm working on my third observatory.) Besides, he's preaching to the wrong audience - I built a portable 1-meter diameter telescope and moved it around frequently. Telescopes are 1.22(Lambda) over D. That means the bigger the better. And get up to date! Big aperture telescopes now shoot through corrected seeing with Speckled Technique. And stop moaning about your pathetic 11-inch size. I know it's small but it's how you use it. I converted a 12.5 inch into 125 inch performance and discovered a new star that the Hubble Space Telescope could not find. We're going to build a big telescope (ULT Project) with the Big Brain and study the edge of the Universe and make new discoveries. You can join us (cup half full) or fault us (cup half empty), the choice anyone can make.
  • HumanoidoHumanoido Posts: 5,770
    edited 2011-11-07 12:42
    Well, for us lay people in the forum, perhaps you can describe how it works. Be sure to use short words and simple sentences. I'm often baffled by complex subject matter. -Phil
    I know you're often baffled and perplexed as your posts prove it but it's you that makes the "subject matter complex." Take Electric Aye's suggestion and read a couple books. He's provided a very good source for a good book on filters and another about refractor element design (Porter series is also good).
  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2011-11-07 13:17
    Here is what a Wikipedia article has to say about correcting chromatic aberration via post-processing (what I assume you mean by a "filter"):
    "In some circumstances it is possible to correct some of the effects of chromatic aberration in digital post-processing. However in real-world circumstances, chromatic aberration results in permanent loss of some image detail. ... In reality, even a theoretically perfect post-processing based chromatic aberration reduction-removal-correction systems do not increase image detail as a lens that is optically well corrected for chromatic aberration would ..."

    This is why a post-processing "filter" which claims to produce images equal to those of an achromat might properly be characterized as "magic." OTOH, if you had some sort of optical filter in mind (other than the narrow-bandpass filters ElectricAye alluded to), please let us in on your secret.

    Thanks,
    -Phil
  • Martin_HMartin_H Posts: 4,051
    edited 2011-11-07 13:46
    The achromatic and apochromatic refractors are nice, but the 5" maksutovs are sold in greater volume. So they give a nice image, portability, and better price point.
  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2011-11-07 13:52
    For the average amateur, portability and ease of setup and use trump tack-sharp image quality and light-gathering power as considerations for purchase. As I stated before, the best telescope for anybody is the one they will use.

    -Phil
  • Duane DegnDuane Degn Posts: 10,588
    edited 2011-11-07 14:22
    Humanoido wrote: »
    Phil is negative about everything.

    Humanoido,

    I strongly disagree. Phil is just stating what many of us are thinking. I agree with what he's said. Your personal shots towards him are very offensive.

    You've been making, at least to me, very wild claims. You give directions to making a saran wrap telescope. Those of us who have used plastic film with water know it doesn't form a nice parabolic surface. It tends to fold and distort.

    Can you show a picture from such a telescope.

    It's one thing to brain storm but you've been presenting wild ideas as if they are tried and true.

    Duane
  • Martin_HMartin_H Posts: 4,051
    edited 2011-11-07 16:29
    For the average amateur, portability and ease of setup and use trump tack-sharp image quality and light-gathering power as considerations for purchase. As I stated before, the best telescope for anybody is the one they will use.

    -Phil

    True, I like my 5" mac because it is so easy to use and fairly compact. A pair of binoculars are also handy for the same reason.
  • Martin_HMartin_H Posts: 4,051
    edited 2011-11-07 16:50
    Humanoid, I wouldn't describe Phil as negative. I've been struggling a few times and his help got me out of the mud. So I would describe him as helpful.
  • ercoerco Posts: 20,256
    edited 2011-11-07 17:32
    PhiPi is one of the sharpest dudes in the forum, period. He's a practical guy who just asks for substantiation when fantastic claims are made, which happens frequently in this thread. When there is demonstrable progress and proof to back it up, he's the first guy to say "well done", and usually quite eloquently. For Phil and myself, this would be a more credible thread if there was more documentation provided.
  • ElectricAyeElectricAye Posts: 4,561
    edited 2011-11-07 19:26
    One of the things on my bucket list is to build a muon telescope and search for signs of intelligent life blowing itself up somewhere in the universe (I'm guessing warp drives are a bit unstable and learning how to build them, never mind drive them properly, is probably a buzz killer.)

    But muon imaging systems in general sound like fun. For example, some dudes effectively x-rayed a volcano sometime back:
    http://www.agu.org/pubs/crossref/2010/2010JB007677.shtml

    And that probably also partly explains why radiation detectors are outlawed in NY city: the bankers don't want you imaging their buildings and detecting where their various vaults are located, etc. Apparently, given enough time, you can see through anything with this technology. Cool thing is, I'm fairly sure this is something a Propeller chip can handle: one of the first things I ever built with the Prop was a coincident photon counter, thanks to its built-in counters. Just place the detector plastic or crystals far apart in a line and start counting coincident pulses and you, too, can map out where all the billionaire bankers keep their gold - or our gold, as the case may be.
  • HumanoidoHumanoido Posts: 5,770
    edited 2011-11-07 22:42
    Optical or Not Optical

    Let's address issue #1. In general, the projects presented here make no claim on the design specifics regarding the level of image formation. That's because it's quite possible some or all of these telescopes won't be designed to form images. The Brain has not yet announced the telescope parameters for the ULT or any of its smaller experimental development siblings. The smaller scopes are experiments with a higher purpose. They are not telescopes designed to be sold or for your viewing pleasure. They answer specific research questions and establish viability of science toward larger projects. Some project experiments show things that work exceptionally well while other projects help to reject certain ideas and designs. In the case of the latter, it prevents money and time being spent on a project that would not produce the results we want. No one knows if this (ULT) will be an optical telescope or not, as the Big Brain has not announced it.
  • HumanoidoHumanoido Posts: 5,770
    edited 2011-11-07 22:44
    MMT MLT Accuracy
    Let's address issue #2. There are a number of other large MMT projects that make specific theoretical claims of the high accuracy required to form the type of optical images they desire, but it does not mean the reality of the system met these theoretical values. Quite the contrary. They found flexure in the mounts holding the individual mirrors and it was virtually impossible to support and move mechanics in the distance of a human hair divided 50 times let alone 500 times. If some research is done reviewing the nomenclature before and after the telescope is built, it may become apparent some politics are involved. Whatever the reason, in the case of at least one MMT, the multiple mirrors were removed and replaced with a single disc.
  • HumanoidoHumanoido Posts: 5,770
    edited 2011-11-07 22:53
    Blown Warp Drive Differentiation with Celestial Objects

    One of the things on my bucket list is to build a muon telescope and search for signs of intelligent life blowing itself up somewhere in the universe (I'm guessing warp drives are a bit unstable and learning how to build them, never mind drive them properly, is probably a buzz killer.)
    There are several techniques using very large telescopes to help differentiate blown warp drives from Quasars, Black Hole emission, exploding Neutron Stars and other phenomena. You may want to merely search for changes the signature of space time distortions created by the matter antimatter displacement. I'm not so sure if you will be restricted to using only a muon telescope. A big light bucket could offer some surprises.
  • HumanoidoHumanoido Posts: 5,770
    edited 2011-11-07 23:10
    Expect the Unexpected

    On to addressing issue #3. These projects are intended to be fantastic. If there's something you've never seen before, don't be surprised. The Big Brain has the claim on fantastic. The Big Brain itself is fantastic. One would not expect anything less. You're right. Projects are out of the box. Crazy sounding. Some things work. Some things don't. We are busy trying new things. New experiments. New science. Working with new materials. Common household items. Shoestrings and chewing gum. Plastic and suction cups. Using new designs. Even duct tape and wire hangers cannot escape.
  • HumanoidoHumanoido Posts: 5,770
    edited 2011-11-07 23:24
    Documentation

    Issue 4 is about the need for more documentation. This is really a balance of spending oodles of time on posting or rather spending the actual time developing the project and utilizing it. So to balance the time, it's currently about 5 percent posting and 95 percent work on projects. To make this level work, the postings are basic summaries that stimulate one's thinking, provide the project synopsis and the food to put together a nice meal. You'll have to do some research along the way, learn some new things, as currently with time constraints, the Brain cannot write a book on every topic or educate on every technical matter. Even assembly must be condensed and summarized. The Brain has lots of projects and the schedule is swift. Some people cannot keep up with the fast pace or need more information to believe it. You may need to fill in some holes to get it. Usually you will see more and more information appear as a project develops so it may be a matter of patience.
  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2011-11-07 23:26
    Humanoido wrote:
    No one knows if this (ULT) will be an optical telescope or not, as the Big Brain has not announced it.

    By what means might such an announcement be forthcoming? IOW, how does the Big Brain (which from all implications in this thread must be sentient by now) communicate with you? Telepathically (per this quote from post #1557)?
    Humanoido wrote:
    Commanded by the demanding and incessant insisting telepresence of the Big Brain getting inside my head, ...

    Or is it something more mundane, such as a video display? Or has the "Big Brain" become simply a metaphor for your own thoughts, desires, and ambitions (not that there's anything wrong with that)? I'm just trying to get a handle here on what you mean exactly when you refer to the "Big Brain" because ... well ... I'm just not sure anymore.

    Thanks,
    -Phil
  • HumanoidoHumanoido Posts: 5,770
    edited 2011-11-08 04:50
    Achromatism Technique

    Way back when we constructed a multiple lens refractor and named it the MLT, we first made a post introducing the concept, then posted the details of how it would function, then began posting build information during and after it was built. Keep in mind many of these posts are written offline and then posted online as time and position becomes available. As I'm often traveling, this works best.

    This is the general outline for most Big Brain Projects. In a follow up post to the first built MLT, a number of tips and techniques were posted for its use. Two of those tips were on the order of correcting for achromatism since the MLT has multiple primaries of single refractor glass which leads to some achromatic aberration. This appears to have raised some questions about how this works, i,e. how can one reduce or eliminate such aberrations from simple lenses.

    We have used one of the three methods outlined to successfully reduce and eliminate evidence of achromatic aberration in the MLT, (a liquid telescope may involve similar situations or not, i.e. the refractive indices of two dissimilar materials may cancel), and as there is now a heated interest in this topic, now is a good time to review.

    The previous discussion is indicative of one obvious thing - you can review all the formula you want but to get a handle on it, you actually have to see it and experience it. When you see it, you know the degree and what it will take to correct. It should also become obvious of how a filter will correct it. If you look at the provided photo in a previous post, it would appear at least one technique has completely eliminated any visibility of AA in the photo.

    For amateur astronomers wishing to tackle achromatism in their images, there are three methods.
    1) apply a selective character wavelength filter to the telescopic image
    2) apply computer image processing to the image
    3) apply an added lens

    In the photo provided that was taken through the MLT, IP was used. Let's call the subtle effect a sheen over the overall image. The sheen has low contrast and can be removed through simple computer image processing. I used the functions of iPhoto and a followup with Preview. These are Mac programs and I currently exclusively use Mac. Photoshop on the Mac works with more functions and has better control over the curve. As you can see in the photo, the stars are pinpoints which indicates the results we wanted are achieved.

    To understand the next effect, one needs a good understanding of exactly what achromatic aberration looks like through a telescope. Do you know exactly? Let's say you don't know or forgot. As a reminder, the image will be color shifted, i.e. the opposite ends of the color spectrum will not come to a focus. In the case of an extended source, or opposing sides of a point source, the appearance is red on one side and blue on the other.

    This manifests itself quite obviously in a Tasco 30mm refractor telescope. This is how I became interested in astronomy. As I looked at the Moon, one edge was red and the other edge was blue. This was fascinating as no one knew why the colors existed. The object itself, aside from the outer fringes will appear tack sharp. In a photo, the fringes will be obvious too. Now, to correct, introduce a transmission character selection filter at mid range to block the red and violet ends of the spectrum. The image will now appear tack sharp and the edge achromatism will disappear.

    The final method involves putting in contact two dissimilar pieces of glass or substrate that can bring the color spectrum to a single focus. As mentioned there are good books and places on the web with more descriptions and more detail. For example, the effect is illustrated here:

    http://www.transtutors.com/physics-homework-help/optics/lens-defects.aspx

    defect1.JPG

    From the web site:
    Chromatic aberration: Image of a white object is coloured and blurred because
    µ (hence f) of lens is different for different colours.
    This defect is called chromatic aberration. µv > µR so fR > fV
    Mathematically chromatic aberration = fR – fv = ωfy
    ω = Dispersive power of lens.
    fy = Focal length for mean colour √fRfv
  • HumanoidoHumanoido Posts: 5,770
    edited 2011-11-08 05:01
    Conceptual Development

    "Way back when we constructed a multiple lens refractor and named it the MLT, we first made a post introducing the concept, then posted the details of how it would function, then began posting build information during and after it was built. Keep in mind many of these posts are written offline and then posted online as time and position becomes available. As I'm often traveling, this often works best."

    Generally this method has not changed. Perhaps someone is getting a little mixed up with the order, thinking the first introduction to a concept is the working model. It is generally not. Often this is the most exciting time of contemplation, examination, and running values and conditions through the initial design. Even by the time of the second post, the idea can still be in developing stage and trying new things. When you start seeing stuff on how it's put together and then actual photos taken through it or of it, you can figure it's in the works, completed or being experimented on, and we'll move on.
  • HumanoidoHumanoido Posts: 5,770
    edited 2011-11-08 05:17
    Membrane Quality in Liquid Telescopes

    The comment in point is about the negative degradation effects of Saran Wrap or other membrane materials in liquid refracting elements.

    We are well aware of many effects of this type of material and for our purpose it is determined the material is quite suitable.

    It is not to say that Saran Wrap is the ultimate material for such a lens. Various different plastics and polymer films and membranes are also being tested. Some of these have exceptional transparency and will probably work better than SW.

    http://en.wikipedia.org/wiki/Saran_(plastic)

    It is also interesting that each time you choose a different material, the effects are different, due to a change in many physical properties.

    People have had good success in imaging through membrane telescopes and optically, similar refractor membrane liquid results are possible.

    If time permits, I will show a photo take of the moon through a dry membrane telescope, corrected with my method of IP, showing the depth of remarkable clarity that should serve well as an example of what can be achieved.

    We are not looking to make a high resolution high precision optical elements with this experimental unusual water bag lens.

    The interesting and simple design will answer some questions about liquid mirrors and lenses of static nature and the affects they may have on telescopes.

    In a future post, we may examine some properties that make these telescopes perform better.
  • HumanoidoHumanoido Posts: 5,770
    edited 2011-11-08 05:31
    Maksutov Telescope
    Martin_H wrote: »
    The achromatic and apochromatic refractors are nice, but the 5" maksutovs are sold in greater volume. So they give a nice image, portability, and better price point.
    These do make nice portable telescopes. Martin, have you looked through one? The Maksutov can perform outstanding with its sharpness and high contrast. Some of the finest images I have ever seen were through various Maksutovs built by Howard Louth who worked as an engineer for Boeing. Those small telescopes are just like small Questars and regularly photo large sun granularity. Planetary and lunar imaging is spectacular. Generally these instruments are smaller but Howard had one around 11-inch size. It was portable and rolled out of his workshop on wheels. These are technically challenging to build so you pay for what you get.
  • HumanoidoHumanoido Posts: 5,770
    edited 2011-11-08 05:40
    JMI Wheely Bar
    On the topic of moving the Celestron around, for handicapped and people with occasional bad backs, or simply for roll-out convenience from the garage, the use of a JMI Wheely Bar add-on can be an effective mobility solution. These work well for the C14 too which is a jump up in weight and massive proportions with the original Celestron equatorial mounting.

    http://www.jimsmobile.com/buy_wheeley_bars.htm
This discussion has been closed.