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astroavani

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About astroavani

  • Rank
    Proto Star
  • Birthday 08/08/1960

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  • Gender
    Male
  • Interests
    Astrofotografia
  • Location
    Canoas, Brazil
  1. An unusual crater

    LOL Ruud!
  2. An unusual crater

    LOL! Finally someone figured out where I got the ship I use to make the photos, the Zeta Rediculi Persei 8 region. From now on I will lose many admirers!
  3. An unusual crater

    An unusual crater! Talking with his friend Cícero Soares, he called my attention to the unusual form of Lavoiser A. I was quite sure that I had never done a specific capture of this crater but I remembered that when I took pictures of the super moon of 2016 it should appear. I checked my files and did not give another, there was this interesting crater. I used to make a specific process of this region and here we can see it in the photo. It is located very close to the lunar northwest limb and therefore in a region that makes it impossible to photograph it from the top which causes that in the photograph of profile can not be noticed its square form. Why are most craters circular? (up to craters found on Earth?) Impacting objects many miles a second into large laboratories, scientists have shown that only the most oblique impacts (less than 10 ° from the horizon) produce elliptical craters. The kinetic energy of a pendulum behaves like the energy of a nuclear bomb. The energy is transferred to the target material by a shock wave, and the shock waves produced by an impact, whether oblique or from the front, propagate hemispherically. This means that energy is being delivered equally in all directions; resulting in a hemispherical void and therefore circular craters. However, conditions in nature do not always reflect the laboratory. In fact, some craters are almost square! A portion of Lavoisier's Edge tells a story of geology before impact. Lavoisier A is a square crater with a diameter of ~ 26 km (16 miles) found in the northwest portion of Oceanus Procellarum. Much of the shape of Lavoisier A is thought to be due to preexisting junctions or flaws in the target rock. These discontinuities create zones of weakness, affecting the way the shock wave travels through the material. Mainly the square corner along the northern edge of the Lavoisier crater is evidence of pre-impact fracturing. We find square craters in other planetary bodies, as in the asteroid Eros and here on Earth! An example of a square crater that has been carefully studied is Meteor Crater in Arizona. This crater formed in layers of sedimentary rocks that have orthogonal vertical joints moving downward, from where the crater formed. The joints interrupted the flow of shock waves in certain directions, preventing the formation of a circular crater. The exact composition of the subsoil is not well known on the Moon but we can predict that something similar may have occurred. Source: LROC / NASA Adjective: Avani Soares https://www.astrobin.com/full/329193/0/?nc=user
  4. Mons Rümker

    THE LUNAR DOME COMPLEX MONS RÜMKER The lunar volcanic complex Mons Rümker lies in the northwestern part of the Oceanus Procellarum, has a diameter of about 65 km and maximum altitude around 1.1 km above the surrounding surface, is the largest known volcanic building on the Moon, a huge dome of volcanic origin, composed of a cohesive grouping of domes, that is, a complex of overlapping domes of smaller domes, most with low slopes and a few steeper ones and for this it presents itself as a discrete formation. It is estimated that the estimated lava volume to create Mons Rümker was about 1,800 km³. According to current studies it is composed of a series of overlapping lava flows. Mons Rümker is aligned with the Aristarchus plateau and the Marius Hills along the axis of Oceanus Procellarum. Several individual domes can be distinguished on the plateau. Rümker is the only dome with the name of a crater. Rümker tricked the selenographers, who in the 19th century thought it was a ruined crater. Lunar domes are smooth undulations between 3 and 20 km wide, and at most 1 km in height. They can be of various shapes and sizes, but the most common are of hemispherical shape with a low profile. Most have very low tilt angles and are the best evidence of volcanic activity on the moon. Many have a small central crater at the peak, which occurs after the end of the magma flow with consequent falling collapse inside. Domes without a peak crater are still of volcanic origin, but appear to have had its central opening covered with lava. Observing lunar domes is a challenging activity that requires dedication and time coupled with good observing conditions. Most domes can not be observed when away from the terminator. As its distance from the terminator increases, it loses contrast and begins to blend with the local terrain, and for all practical purposes the dome disappears from view. For the reasons mentioned, most authors recommend that observations of the domes should be performed near the terminator, where the solar altitude does not exceed 4-5 degrees. Other observers suggest 8 degrees of solar altitude as the maximum, but notably between 4-5 degrees of solar altitude, the smaller low-profile domes and the details of the larger domed surface become very visible. There are only a few domes that can withstand high solar altitudes without disappearing in their local areas, one of them can be seen in the photo and is indicated as Mairan T. Even a small 3 "refractor telescope will show the larger domes on the moon, but for a more serious work a refractor of no less than 4" or a reflector, not less than 6 "is needed.Another item that is almost indispensable is a good equatorial mount that can provide constant monitoring Because domes are objects that are difficult to observe, it is often necessary to use high powers in the telescope, which prevents the use of a handheld telescope for long observations. and well collimated 8 "mounted on an equatorial one can make excellent observations and records. Colimation of the optics should be emphasized to have a clear and good image that is paramount in order to provide the observer with the ability to capture those evasive domes, especially when atmospheric conditions are not perfect, which will happen most of the time. It is recommended whenever possible the use of high power. In good viewing conditions there is no reason why good optics can not be pushed to achieve its maximum. Increases in the order of 200 to 300X are desirable, filters can also be used, but they are not a fundamental requirement. It is also important to mention that effective observation of the dome can not be performed with the moon too low, near the horizon. A minimum altitude of 45 degrees from the horizon is usually necessary to reduce atmospheric effects. A good seeing is important although some of the larger domes can be observed with some turbulence. Source: LPOD - Charles Wood VTOL - Vaz Tolentino Lunar Observatory THE ALS LUNAR DOME SECTION - Guido Santacana and Eric Douglas - American Lunar Society JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 11 - Bruce A. Campbell, B. R. Hawke, and Donald B. Campbell Research and adaptation: Avani Soares https://www.astrobin.com/full/328975/B/?nc=user
  5. Babage and South

    Babage and South On a night of mediocre seing, only one capture was saved, yet our view of the formations near the lunar northwest limb is not due to other places on the Moon. Both Babage and South due to their sizes are considered walled plains. In fact they are very old craters almost completely destroyed and submerged in the events that occurred in later times. Babage with its 143 km in diameter was totally corroded and modified by the multitude of subsequent impacts, until all that remained was that ring of rounded hills that can be seen sublime in this photo made at extremely low angle of illumination. In its floor we can perceive numerous other craters being that the greater is Babage A that with its 32 km of diameter could very well be named like an independent crater. South a crater of 104 km in diameter underwent an even greater degradation process than Babage being that of its edge only remained a few hills located to the south and the most prominent section located to the northwest in the border with Babage. It was a crater totally flooded by lava having its floor level and no prominent features. "Look at the Moon with other eyes!" That's what my friend Chuck Woods always says, so why not start here? Text: Avani Soares https://www.astrobin.com/full/328798/0/?nc=user
  6. Catena Abulfeda

    A pity friend Jules, I hope you still have the opportunity to observe our Moon from a good place and with a powerful tele, it is an unforgettable sight!
  7. Catena Abulfeda

    Catena Abulfeda Watching small lunar craters stretched in a row, makes us wonder what could have caused that. Even today, there are serious doubts about the origin of these craters. Will it be caused by rebound material? Some believe in an endogenous origin, that is, through the volcanism originated in the Moon itself. However, several chains of craters on the Moon and elsewhere in the Solar System do not seem to fit into either of the two previous scenarios. The mystery was solved in 1993 with the discovery of Comet Shoemaker-Levy 9. As you recall, it was not a single comet, but a chain of twenty-one comet fragments created a year earlier when Jupiter's gravity ripped the comet original. SL-9 fell on Jupiter in 1994, and we can imagine that if Jupiter had a solid surface, a chain of craters would probably result from any particles of SL-9 that survived the passage through the atmosphere. In fact, these chains of craters were found on the Moon and Ganymede. Now we know that fragmented comets are not uncommon. Sunlight alone can destroy its fragile nuclei. The separation of Comet Schwasmann-Wachmann 3 is a recent example. And there is evidence that many asteroids are actually aggregates of dust and rock barely held together by a slight fragment of gravity. If these things hit the earth, they would probably create a chain of craters. If you have not guessed yet, the word "catena" is a Latin term adopted by the International Astronomical Union to mean a chain of small craters. In 1994, Jay Melosh and Ewen Whitaker announced the discovery of two crater chains on the Moon, neither of which seems endogenous or secondary to a greater impact. A fairly large chain is near the Abulfeda crater (photo) and the other is near Davy (https://www.astrobin.com/full/253411/0/?nc=user). The chain of Davy's crater is particularly interesting because it is a nearly perfect line of twenty-three fragments each with only a few kilometers in diameter. This is significant because it proves that the events of multiple impacts and the resulting crater chains actually occurred in our Earth-Moon system. I think that all the assumptions are valid, some must have endogenous origin, others are formed by rebound material and some must have formed from fragmented comets. The interesting thing would be to try to discover the origin of each Catena, but I think it would only be possible through the search in the place. Our Moon has many secrets that still deserve to be unraveled, you can become another trying to unravel them! Text: Avani Soares https://www.astrobin.com/full/328515/0/?nc=user
  8. Lunar South Pole

    Thanks Ron!
  9. Lunar South Pole

    Ele esta legendado para inglês amigo Ruud!
  10. Lunar South Pole

    Your words leave me extremely moved friend Barkis, make me increasingly try to do my best to make good photographs, do not forget to look at the Parsec Observatory film:
  11. Lunar South Pole

    Hello Ian, filters are extremely important in both lunar and planetary photography. Many complain of a bad seeing and forget the wonders that an IR pass filter 685 or 742 nanometers can produce. Having aperture, we have enough light to operate with ever deeper cutting filters on the IR and at the same time we can use high speeds that allow us to freeze those brief moments of good seeing and thus produce that photo that makes the difference. Another interesting example of the usefulness of IR Pass filters can be seen in Saturn, only with filters in this range can we distinguish the hexagonal polar hurricane eye. This all demonstrates that we must deeply study the use of the filters and know how to use them with mastery.
  12. Lunar South Pole

    This time instead of talking about the formation itself let's talk about how the photo was taken to get these subtle details that appear here. The telescope used was a Celestron Schimitd Cassegrain Edge line, commonly known as C14 HD. The assembly used was CGE PRO from the same company. The camera used was colored ASI 290 coupled with a Baader IR Pass filter 685 nm. General considerations For lunar photography as well as high-resolution planetary a good independent desing telescope is essential, we can not deny that the larger the aperture the greater the resolution capability. The focal length is also a fundamental factor and it is usually ideal to work between f / 20 and f / 35 and for each telescope it is important to define the best d / f in relation to the camera used because this is directly related to the pixel size. In high resolution photography you usually work with oversampling, using large increases. It does not have to be said that a good collimation is fundamental as well as a reasonable seeing always favors obtaining better results, the correct focus is critical to a high resolution photo and the image must be the most perfectly focused on the capture screen. My Account Good telescopes have been around for a long time, the breakthrough of high resolution photography was only possible with the appearance of the current generation of cameras that allowed high speeds combined with great sensitivity. Cameras like ASI 174, 224 and 290 allow you to dribble much of the bad seeing and get high quality images. This image of the south pole, for example, was obtained on a medium seeing night, I calculate something around 3/5, but I used speeds of up to 100 fps in frames of 1280 X 960. This allows to capture those brief moments of good atmospheric stability (lucky frames) that will be separated from the bad frames during processing to form the final image. In this photo with ASI 290 of the 2000 captured frames I could use 308 to stack which allows to create a photo with low noise and extract many details. Filters Filters are fundamental in high resolution photography and should be used according to the goal you want to achieve, in particular lunar photography, IR filters allow a remarkable gain and even make it possible to take pictures on those nights that without them would be completely impossible. The filter that I use the most is the IR Pass 685nm which favors long-wave (infrared spectrum) passages, these waves are much less subject to turbulence than the visual spectrum (RGB) waves, but there are others more open or closed and up to a 610 Long Pass nm can help a lot when seeing is a little better. If seeing is really good, I highly recommend using a simple Green color filter, it increases the resolution because it has a shorter wavelength. Barlows and powermates In high resolution photography are essential and there is any brand that is suitable. Excuse me skeptics but if you really want to get a high definition photo, quality is a fundamental factor, you should always prefer the powermates because they are one step above the barlows, but if this is not possible you should opt for quality barlows recognized. They are very important because only with them can achieve the appropriate focal reasons for the photos that we want. Programs of astrophotography Below I will list in order the programs that I use to make my moles as well as some general considerations about their purpose. Fire Capture: Undoubtedly it is one of the best free programs for lunar and planetary capture, easy to download (http://www.firecapture.de/). This program seems a little complicated but once you get used to it you can not use another one, in the link itself, where low orientation tutorials exist, it has many features that make it much easier to get good photos and for those who will start using it one of the The main points is the control of the hystogran to obtain even shade photos and easy to process. We should try not to overdo the Gain so as not to make the photo very noisy and all the success of a good capture is directly related to the good balance between Gain, Range and Exposure. There are no fixed values because everything depends on the telescope and aperture used. 2. AS! 2 (AS! 3 already exists): I used Registax 6 to select the best frames and their stack, but AS! 2 or AS! 3 (http://www.autostakkert.com/ ) does this much better because it is a specific program only for this stage of processing. AS! 2 lets you output two TIF files (photos), one of which is already preprocessed and I use it to make the final photo, since I started to use AS! 2 I never needed Registax anymore and thus saved a step delayed post-processing. A brief tutorial of AS! 2 can be seen here: http://astroavani.no.comunidades.net/tutorial-as2 3. Photofiltre: it is an editing program (http://www.baixaki.com.br/download/photofiltre.htm), use only to adjust the brightness and contrast can also be used the filters sharpen and soften in case there is need of give a smoothed or pulled in the details. If anyone is interested in a simple tutorial to test it you can find here: http://astroavani.no.comunidades.net/usando-o-photofiltre-tutorial 4. Fitswork: it is an excellent deconvolution program, with it we can fine tune the image and pull lots of details, can be downloaded here: http://www.fitswork.de/software/softw_po.php I advise to read the tutorials and do a lot of tests with it because in fact it is the program that makes all the difference in the finalization of the photo bringing to the surface numerous details and increasing greatly the final resolution. Final considerations Of course reading does not seem complicated, but in fact getting good photographs requires good equipment, a lot of training and practice to realize the subtleties of every step and get that photo that really makes a difference. Patience, perseverance, willingness to learn ever even missing a lot, and humility to accept praise and criticism is mainly that can make us all a great astrophotographer. Photo and Text: Avani Soares https://www.astrobin.com/full/326848/0/
  13. Parsec Observatory - Avani Soares

    Thank you, friend Pete! It really is good to meet people who hide behind Nick sometimes. Of course this is not always advisable, but we can not deny that it creates greater intimacy.
  14. Parsec Observatory - Avani Soares

    It's a great telescope! I had two exactly alike and all two had very good optics, this makes us think that good optics is the rule, not the exception. I also really like the mechanics of GSO being the first to offer crayford focal point as standard on relatively inexpensive cost. Collimation is easy and will last for a long time if you consider other Newtonians I've had such as Sky Watcher and Orion UK. Anyway I have a certain passion for them and I can say that they are worth every cent invested, only, in my case you can not compete with a C14 still above the Edge line.
  15. A cool video my friend Rafael Compassi made about the Parsec Observatory: https://youtu.be/TzUTI4_c-O4
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