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موضوع: Astronomical sketching

  1. Top | #1
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    Jun 2011
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          Astronomical sketching

    Hello my dear friends
    As you know, astronomical sketching is one of the best way to record our observings

    In this topic we will start from general points that we should know about sketching and then talk about the methods and techniques that we can use

    to improve our ability for sketching the sky & its beautiful objects & events!

    so stay with us!




  2. Top | #2
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          benefits

    first of all let me say something:You don’t have to be an artist to sketch what you see through a telescope (or naked eye). All you need is an eye for
    details and the patience (maybe starting with simple objects, be a better idea) to practice your technique.


    it also help train your eye to see details and I can assure you ,its an important thing in observation too. In fact , Sketching improve your attention for details more, and it causes you to ask from yourself what you actually see? so, Drawing , develops your visual skills and enables you to become a better, more accurate observer.

    The other reason for sketching: You’ll have a permanent record of what you saw! and when you look back on it later , you find them really interesting. they also can be a memory

    Sketches give you a way to compare what you see in different scopes , different condition &... and you can show other people what you really see.


    and more interesting : Drawing increases your chances of making a scientific discovery! If you had an experience to draw celestial object before , you are the first one to find out the changes in them if happend

    anyway if you dont believe me just do it once and I am sure you find it interesting
    ویرایش توسط stargazer : 02-25-2012 در ساعت 12:15 AM

  3. 13 کاربر مقابل از sara shahabi عزیز به خاطر این پست مفید تشکر کرده اند.


  4. Top | #3
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    تاریخ عضویت
    Jun 2011
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    ok , now we want to start the main point , but before that , let's talk about the history of sketching. we can see sketches of the moon, Mars or Saturn from scientists like Galileo, Lowell, Huygens, Cassini. Most of these scientists weren’t artists, and their sketches often weren’t pretty as you can see below (I mean their work are not artistic masterpiece) , but they are really valuable! and the early astronomers traded their sketches, and compared what they saw while they tried to understand it

    and the other point is: these astronomers did their sketches just by pencil and paper and we can do it like that ,too (although we have sybersketching (by tablet or sth) , but I mean we don't need special equipment for drawing and it also can be easier from photography

    these are galileo's sketches from the moon and jupiter with its moons (with this sketches he find out that they turn around jupiter and not earth)i






    ویرایش توسط stargazer : 02-25-2012 در ساعت 11:59 PM

  5. 9 کاربر مقابل از sara shahabi عزیز به خاطر این پست مفید تشکر کرده اند.


  6. Top | #4
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    I think this is a good time to introduce an excellent website for you to check it every day. Its name is ASOD (Astronomical Sketch Of Day), And this is the address:

    http://asod.info/

    امضای ایشان
    اینجا جنگی در کار نیست...
    آرامش است و سکوت.
    سکوتی از جنس آواز شب مرگ قو
    و آرامشی به رنگ خدا
    آهسته صحبت کنید
    مبادا این آرامش را بهم بزنید
    ...



  7. 9 کاربر مقابل از Negar Najafi عزیز به خاطر این پست مفید تشکر کرده اند.


  8. Top | #5
    کاربر ممتاز

    عنوان کاربر
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    تاریخ عضویت
    Jun 2011
    شماره عضویت
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    تشکر شده 3,386 بار در 317 ارسال

    thanks dear Negar for introducing asod

    I think , if anyone want to learn , she/he should check the websites and see different works of astronomers. and if you don't want to learn you just can check this site or similar sites to see beauty of celestial objects as we can observe through the telescope
    --------------------------------------
    Did you have an experience like this?: stargaze without telescope! with unaided eye we can see constellation , meteor(bursts), moon & lunar eclipse&.../ If we can see them , then we can draw them and as you can see below for meteorbursts we can draw constellation firstand use them as a guide for marking meteors.

    this two sketches belong to perseid (meteor outburst) by two different person (right: Aleksander Cieśla / left:Juanchin) sourse:asod.info



    p.s:If you did sketches by nakedeye please share it with us



  9. 9 کاربر مقابل از sara shahabi عزیز به خاطر این پست مفید تشکر کرده اند.


  10. Top | #6
    کاربر ممتاز

    عنوان کاربر
    کاربر ممتاز
    تاریخ عضویت
    Jun 2011
    شماره عضویت
    906
    نوشته ها
    346
    تشکر
    2,507
    تشکر شده 3,386 بار در 317 ارسال

          the way of observing and sketching

    it's better to provide the best situation for drawing sketch. at first you'll face with two opposite subject. one, for seeing a celestial object you need your eyes get used to darkness, and the second , for seeing the paper & drawing you need to light! so for this purpose it's better to use a red light torch, because it has the least effect on your eyes. & also you should try to watch that object for more duration with great attention (punctuality), it causes you memorize more details for drawing.

    when you are watching from optic it's better to keep your hands beside your head or eyes to prevent from entering light.

    the next point is
    choosing a good position for drawing, like sitting down. so if it's possible try to sit down instead of standing up.
    -----------------------------
    and I should thank from dear stargazer for helping me in translating my ideas and thoughts to english.
    ویرایش توسط stargazer : 03-13-2012 در ساعت 07:38 PM دلیل: your welcome dear sara,& i thank you for sharing your educations here :)

  11. 8 کاربر مقابل از sara shahabi عزیز به خاطر این پست مفید تشکر کرده اند.


  12. Top | #7
    کاربر فعال
    مدیر تالار

    عنوان کاربر
    ديوان سالار ويكی نجوم
    تاریخ عضویت
    Sep 2011
    شماره عضویت
    1479
    نوشته ها
    1,068
    تشکر
    14,157
    تشکر شده 11,960 بار در 1,080 ارسال

          Sketching the transit of Venus-1

    On June 5-6, astronomers across much of the world will focus their attention on a cosmic rarity – a transit of Venus across the sun. Such Earth-Venus-sun alignments occur in pairs 8 years apart – the pairs separated by alternating intervals of 105 ½ and 121 ½ years. The most recent Venus transit occurred in 2004, so this is our last opportunity to witness one in our lifetimes
    .
    For this reason, many amateur astronomers will be working feverishly to record and document the event, taking images with digital cameras mounted on their telescopes. What if you lack the equipment and expertise to create a Venus transit photo album? Fear not! With pencil and paper and a little patience, you can fashion an attractive and accurate rendering of the transit.




    Sketch of Transit of Venus 1769


    Step 1. Getting Ready

    Start by gleaning as much information about the Venus transit as you can. You’ll need to know the basics – the nature of a Venus transit, how to observe it safely (remember, the sun plays a key role in the transit!), when it will be visible, and where to best set up for an optimum view.

    .
    The centerpiece of your rendering will be a detailed sketch of the sun upon which you’ll overlay small black disks to represent the progress of Venus during the transit. In the days preceding transit, make a practice sketch of the sun following the technique outlined below


    To be continued.....
    امضای ایشان
    وقتی خدا را دیدم که مشکلم را حل می کرد، من به توانایی او ایمان می آوردم

    و وقتی حل نمی کرد


    می فهمیدم او به توانایی من ایمان دارد...


  13. 10 کاربر مقابل از هانیه امیری عزیز به خاطر این پست مفید تشکر کرده اند.


  14. Top | #8
    کاربر فعال
    مدیر تالار

    عنوان کاربر
    ديوان سالار ويكی نجوم
    تاریخ عضویت
    Sep 2011
    شماره عضویت
    1479
    نوشته ها
    1,068
    تشکر
    14,157
    تشکر شده 11,960 بار در 1,080 ارسال

          Sketching the transit of Venus-2

    Step 2. Sketching the Sun

    Don’t bother purchasing expensive art paper, easel, and paints. A standard 8 ½ by 11 inch (or 210 by 297 mm) sheet of white copy paper secured to a clipboard, some #2 pencils with erasers, and a compass will suffice.
    Near the top of the paper, use a compass to lightly trace out a circle between 4 and 6 inches (10 to 15 cm) diameter to represent the sun. Whether using eyepiece projection or solar filter, start with a thorough visual overview of the sun, using low-power (25-50x) to capture the entire solar disk. Like an artist, study your subject carefully before putting pencil on paper. Pay particular attention to the location, size, and shape of sunspots.
    If you’re viewing with a solar filter, compose your sketch by alternating brief glances at the eyepiece with equally brief pencil and paper sessions. Individuals projecting the sun’s image have a slight accuracy advantage over the filter users. Because the sketch sheet can be used as a projection screen, center the sun’s image on the predrawn circle and “trace in” the sunspots


    .


    With either method, sketch lightly at first. Don’t commit to final detail until you’re confident that what you have on paper closely matches the actual view. When drawing sunspots, gently shading the outer penumbral regions before darkening in the central umbrae. Notice that the edge of the solar disk is darker than the center – a phenomenon known as “limb darkening.” You can duplicate limb darkening by lightly shading with the edge of your pencil the periphery of the sun in your sketch, and then blending it in with finger or eraser. Once you’ve mastered the technique for sketching the sun, you’re ready for the transit



    Sketch of Transit of Venus 1761

    To be continued.....
    امضای ایشان
    وقتی خدا را دیدم که مشکلم را حل می کرد، من به توانایی او ایمان می آوردم

    و وقتی حل نمی کرد


    می فهمیدم او به توانایی من ایمان دارد...


  15. 12 کاربر مقابل از هانیه امیری عزیز به خاطر این پست مفید تشکر کرده اند.


  16. Top | #9
    کاربر فعال
    مدیر تالار

    عنوان کاربر
    ديوان سالار ويكی نجوم
    تاریخ عضویت
    Sep 2011
    شماره عضویت
    1479
    نوشته ها
    1,068
    تشکر
    14,157
    تشکر شده 11,960 بار در 1,080 ارسال

          Sketching the transit of Venus-3

    Step 3. Transit Day Tactics

    As Transit Day approaches, assemble the materials you’ll need. Besides the essentials (telescope, projection screen or solar filter, eyepieces, and sketching materials), add a printed timetable of the various stages of the transit as well as an accurate watch to keep track of time.
    Arrive at your observing site an hour or two before the transit begins (before sunrise, if the transit will already be in progress then). If you’re able to capture the onset of the transit, set up your scope and make a detailed drawing of the sun in advance of first contact. Once you see the first “nick” in the sun’s edge, note its location on your sun sketch and record the time. From here on in, make an observation every half hour, each time plotting the location of Venus with a dark circle and writing down the time. Because Venus has an apparent diameter 1/32nd that of the sun, you’ll signify its disk by drawing circles of the appropriate scale (for example, 3/16th inch [5mm] for a 6-inch sun) and then darkening them in. Can’t draw circles? Use a template that contains circles of various sizes. Continue these half-hour observations until the transit ends or is interrupted by sunset. If the transit is already in progress at sunrise, plot the location of Venus on the sun’s disk first and then ‘flesh’ out your solar sketch.



    There are two instances during a Venus transit when you’ll want to switch to high magnification (100x or more) and make a separate drawing. These are moments associated Venus’ entry and departure from sun’s disk (ingress and egress). Shortly after Venus has completely entered the sun’s disk, see if you can detect a thin black strip between Venus and the edge of the sun. This phenomenon is known as the “black drop.” In the lower left corner of your sketch sheet, trace out an arc representing the portion of the solar disk nearest Venus (no need to waste time and paper drawing the entire solar disk). Then add Venus and the “black drop,” if visible, using the circle on your template that best approximates the size of Venus as it appears through the telescope. If you’re able to view egress, follow the same procedure as Venus nears the edge of the solar disk.





    1874 Venus Transit Expedition
    Summary

    All too soon, the Venus transit will be over. You’ll never see one again. By sketching the event, however, you’ll have a permanent record and worthwhile reminder of the Great Venus Transit of 2012. Who knows? You may even want to pass it on to future generations of your family until the next transit in 2117.



    From: http://transitofvenus.nl/wp/


    I hope Clear Skies for you

    امضای ایشان
    وقتی خدا را دیدم که مشکلم را حل می کرد، من به توانایی او ایمان می آوردم

    و وقتی حل نمی کرد


    می فهمیدم او به توانایی من ایمان دارد...


  17. 10 کاربر مقابل از هانیه امیری عزیز به خاطر این پست مفید تشکر کرده اند.


  18. Top | #10
    کاربر فعال
    مدیر تالار

    عنوان کاربر
    ديوان سالار ويكی نجوم
    تاریخ عضویت
    Sep 2011
    شماره عضویت
    1479
    نوشته ها
    1,068
    تشکر
    14,157
    تشکر شده 11,960 بار در 1,080 ارسال

          Transit of Venus Across the Sun Through History

    Astronomical sketching         



    James Ferguson's Sketch of the 1761 Venus Transit



    Credit: NASA Goddard Space Flight Center Sun-Earth Day

    James Ferguson's sketch of the path of Venus across the sun disk on June 6, 1761 emphasized the dryly technical aspects of the event



    .


    Lomonosov's Venus Atmosphere Sketch

    Credit: NASA Goddard Space Flight Center Sun-Earth Day

    The atmosphere of Venus seen during the 1761 transit was sketched
    by Russian astronomer Lomonosov. Here the atmosphere is sketched as a ring in figs. 6 and 7




    Sketch of Transit of Venus 1769


    Credit: NASA Goddard Space Flight Center Sun-Earth Day

    By the Venus transit of December 8, 1874, photography had been invented, and hundreds of photographs were taken of the event,
    though few were useful enough for scientists. Over $1 million was spent worldwide on observations. The sketch shown here is of the transit as observed in London

    From: http://www.space.com/
    امضای ایشان
    وقتی خدا را دیدم که مشکلم را حل می کرد، من به توانایی او ایمان می آوردم

    و وقتی حل نمی کرد


    می فهمیدم او به توانایی من ایمان دارد...


  19. 6 کاربر مقابل از هانیه امیری عزیز به خاطر این پست مفید تشکر کرده اند.


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