kookoo_gr 12 Δημοσιεύτηκε Απρίλιος 21, 2009 Ωρια η φωτο αλλα το μπλε σου εχει φυγει λιγο πανω δεξια με ενα RGB allign στο registax θα ειναι μια χαρα την εχω φτιαξει λιγο αν θες πες μου mail να σου την στειλω
kookoo_gr 12 Δημοσιεύτηκε Απρίλιος 22, 2009 Δεν εχει να κανει με εσενα ή τον εξοπλισμο σου αυτο το φαινομενο. απλα οφειλετε στο φαινομενο της διασπορας, οσο πιο χαμηλο το υψος του αντικειμανου τοσο πιο μεγαλη η διασπορα των χρωματων του φασματος. πιο συγκεκριμενα σου παραθετω απο το βιβλιο Lunar and Planetary webcam user's guide του Martin Mobberley τα εξης So far we have mentioned little about the color aspects of planetary image processing,but a vital understanding of color and the eye/brain perception of whatappears on your monitor screen is essential.From latitudes well away from the equator, the planets are never going to bedirectly overhead. This instantly causes a problem with respect to atmospheric dispersion,i.e., the splitting up of colors into a spectrum. We have all seen the way inwhich a prism splits light up into its constituent colors. Well, the Earth’s atmospherecauses the same effect: the lower the object’s altitude, the worse the dispersion. Theeffects are especially notable on the Moon, where bright crater edges will be fringedwith red and blue. Unfortunately, atmospheric dispersion is significant enough toseverely limit a telescope’s resolution on any planet lower than 35 degrees altitude.A planet at 90 degrees altitude, that is, directly overhead, will have no color disper-Lunar and Planetary Webcam User’s 94 Guidesion. At 60 degrees altitude (a typical best case scenario for observers in the U.K.),the visual spectrum from red to blue will be smeared across 0.35 arc-seconds, i.e., thetheoretical resolution of a 30-cm telescope. Move down to 45 degrees altitude andthe visual spectrum will be smeared over 0.6 arc-seconds, i.e., roughly the resolutionof a 20-cm telescope. Things then get dramatically worse! At 30 degrees above thehorizon dispersion will be 1 arc-second and at 18 degrees, 2 arc-seconds. Of course,at these low altitudes there will be other undesirable effects, too, as the light is comingthrough a lot of air, seeing will suffer and the image will look dimmer.Fortunately, for the webcam imager, there is a partial solution to atmosphericdispersion. All digital images are constructed from red, green, and blue values,which can, at the user’s discretion, be separated into their respective channels. Forexample, Registax has a feature called RGB shift (Figure 8.1) in which the user can choose to move the red, green, and blue components of each image with respect toeach other until no color fringes are seen at planetary limbs or around brightcraters. Of course, this is not a perfect solution, but, aesthetically, a planet withoutblue and red fringes on opposite edges, looks much better. Needless to say, whena planet transits the local meridian (due south from the northern hemisphere anddue north from the southern), it is at its highest point and this is the point of leastdispersion. Another solution to dispersion is to use an optical arrangement bywhich prisms reverse the damage inflicted by the atmosphere. This might seemlike a horrendous optical problem, but, in fact, AVA (Adirondack VideoAstronomy) has recently marketed an affordable wedge prism corrector that canbe set to correct atmospheric dispersion at a variety of altitudes. I remember seeingsuch a device in 1984, when I visited the legendary optician Horace Dall in hishome, but now such devices are available commercially.
kookoo_gr 12 Δημοσιεύτηκε Απρίλιος 22, 2009 Δεν εχει να κανει με εσενα ή τον εξοπλισμο σου αυτο το φαινομενο. απλα οφειλετε στο φαινομενο της διασπορας, οσο πιο χαμηλο το υψος του αντικειμανου τοσο πιο μεγαλη η διασπορα των χρωματων του φασματος. πιο συγκεκριμενα σου παραθετω απο το βιβλιο Lunar and Planetary webcam user's guide του Martin Mobberley τα εξης So far we have mentioned little about the color aspects of planetary image processing,but a vital understanding of color and the eye/brain perception of whatappears on your monitor screen is essential.From latitudes well away from the equator, the planets are never going to bedirectly overhead. This instantly causes a problem with respect to atmospheric dispersion,i.e., the splitting up of colors into a spectrum. We have all seen the way inwhich a prism splits light up into its constituent colors. Well, the Earth’s atmospherecauses the same effect: the lower the object’s altitude, the worse the dispersion. Theeffects are especially notable on the Moon, where bright crater edges will be fringedwith red and blue. Unfortunately, atmospheric dispersion is significant enough toseverely limit a telescope’s resolution on any planet lower than 35 degrees altitude.A planet at 90 degrees altitude, that is, directly overhead, will have no color disper-sion. At 60 degrees altitude (a typical best case scenario for observers in the U.K.),the visual spectrum from red to blue will be smeared across 0.35 arc-seconds, i.e., thetheoretical resolution of a 30-cm telescope. Move down to 45 degrees altitude andthe visual spectrum will be smeared over 0.6 arc-seconds, i.e., roughly the resolutionof a 20-cm telescope. Things then get dramatically worse! At 30 degrees above thehorizon dispersion will be 1 arc-second and at 18 degrees, 2 arc-seconds. Of course,at these low altitudes there will be other undesirable effects, too, as the light is comingthrough a lot of air, seeing will suffer and the image will look dimmer.Fortunately, for the webcam imager, there is a partial solution to atmosphericdispersion. All digital images are constructed from red, green, and blue values,which can, at the user’s discretion, be separated into their respective channels. Forexample, Registax has a feature called RGB shift (Figure 8.1) in which the user can choose to move the red, green, and blue components of each image with respect toeach other until no color fringes are seen at planetary limbs or around brightcraters. Of course, this is not a perfect solution, but, aesthetically, a planet withoutblue and red fringes on opposite edges, looks much better. Needless to say, whena planet transits the local meridian (due south from the northern hemisphere anddue north from the southern), it is at its highest point and this is the point of leastdispersion. Another solution to dispersion is to use an optical arrangement bywhich prisms reverse the damage inflicted by the atmosphere. This might seemlike a horrendous optical problem, but, in fact, AVA (Adirondack VideoAstronomy) has recently marketed an affordable wedge prism corrector that canbe set to correct atmospheric dispersion at a variety of altitudes. I remember seeingsuch a device in 1984, when I visited the legendary optician Horace Dall in hishome, but now such devices are available commercially.
Aggelos Kechagias 50 Δημοσιεύτηκε Απρίλιος 22, 2009 Παρα πολυ καλη προσπαθεια για πρωτη φορα μανο ευγε. Συνεχισε ετσι συντομα θα τον δουμε και καλυτερο μπορεις ανετα .
planetman 26 Δημοσιεύτηκε Απρίλιος 22, 2009 1) Ήταν αρκετά ψηλά ο πλανήτης. 2) Ποιος είπε πως ήταν η 1η φορά;
planetman 26 Δημοσιεύτηκε Απρίλιος 22, 2009 1) Ήταν αρκετά ψηλά ο πλανήτης. 2) Ποιος είπε πως ήταν η 1η φορά;
petrosl 34 Δημοσιεύτηκε Απρίλιος 22, 2009 Συγγνώμη παιδιά μπερδεύτικα από την περιγραφή της φωτογραφίας. Όπως και να 'χει όμως η φωτό είναι πολύ καλή.
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