Κρόνος - 17-04-09

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

Πολύ καλή η πρώτη σου προσπάθεια. Μπράβο!

Δεν ξέρω γιατί μου συμβαίνει αυτό με τα χρώματα...

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 what

appears on your monitor screen is essential.

From latitudes well away from the equator, the planets are never going to be

directly 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 in

which a prism splits light up into its constituent colors. Well, the Earth’s atmosphere

causes the same effect: the lower the object’s altitude, the worse the dispersion. The

effects are especially notable on the Moon, where bright crater edges will be fringed

with red and blue. Unfortunately, atmospheric dispersion is significant enough to

severely 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 Guide

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., the

theoretical resolution of a 30-cm telescope. Move down to 45 degrees altitude and

the visual spectrum will be smeared over 0.6 arc-seconds, i.e., roughly the resolution

of a 20-cm telescope. Things then get dramatically worse! At 30 degrees above the

horizon 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 coming

through a lot of air, seeing will suffer and the image will look dimmer.

Fortunately, for the webcam imager, there is a partial solution to atmospheric

dispersion. All digital images are constructed from red, green, and blue values,

which can, at the user’s discretion, be separated into their respective channels. For

example, 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 to

each other until no color fringes are seen at planetary limbs or around bright

craters. Of course, this is not a perfect solution, but, aesthetically, a planet without

blue and red fringes on opposite edges, looks much better. Needless to say, when

a planet transits the local meridian (due south from the northern hemisphere and

due north from the southern), it is at its highest point and this is the point of least

dispersion. Another solution to dispersion is to use an optical arrangement by

which prisms reverse the damage inflicted by the atmosphere. This might seem

like a horrendous optical problem, but, in fact, AVA (Adirondack Video

Astronomy) has recently marketed an affordable wedge prism corrector that can

be set to correct atmospheric dispersion at a variety of altitudes. I remember seeing

such a device in 1984, when I visited the legendary optician Horace Dall in his

home, but now such devices are available commercially.

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 what

appears on your monitor screen is essential.

From latitudes well away from the equator, the planets are never going to be

directly 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 in

which a prism splits light up into its constituent colors. Well, the Earth’s atmosphere

causes the same effect: the lower the object’s altitude, the worse the dispersion. The

effects are especially notable on the Moon, where bright crater edges will be fringed

with red and blue. Unfortunately, atmospheric dispersion is significant enough to

severely 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., the

theoretical resolution of a 30-cm telescope. Move down to 45 degrees altitude and

the visual spectrum will be smeared over 0.6 arc-seconds, i.e., roughly the resolution

of a 20-cm telescope. Things then get dramatically worse! At 30 degrees above the

horizon 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 coming

through a lot of air, seeing will suffer and the image will look dimmer.

Fortunately, for the webcam imager, there is a partial solution to atmospheric

dispersion. All digital images are constructed from red, green, and blue values,

which can, at the user’s discretion, be separated into their respective channels. For

example, 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 to

each other until no color fringes are seen at planetary limbs or around bright

craters. Of course, this is not a perfect solution, but, aesthetically, a planet without

blue and red fringes on opposite edges, looks much better. Needless to say, when

a planet transits the local meridian (due south from the northern hemisphere and

due north from the southern), it is at its highest point and this is the point of least

dispersion. Another solution to dispersion is to use an optical arrangement by

which prisms reverse the damage inflicted by the atmosphere. This might seem

like a horrendous optical problem, but, in fact, AVA (Adirondack Video

Astronomy) has recently marketed an affordable wedge prism corrector that can

be set to correct atmospheric dispersion at a variety of altitudes. I remember seeing

such a device in 1984, when I visited the legendary optician Horace Dall in his

home, but now such devices are available commercially.

Παρα πολυ καλη προσπαθεια για πρωτη φορα μανο ευγε.

Συνεχισε ετσι συντομα θα τον δουμε και καλυτερο μπορεις ανετα .

1) Ήταν αρκετά ψηλά ο πλανήτης.

 

2) Ποιος είπε πως ήταν η 1η φορά;

1) Ήταν αρκετά ψηλά ο πλανήτης.

 

2) Ποιος είπε πως ήταν η 1η φορά;

Με μπερδεψε ο πετρος πιο πανω

Συγγνώμη παιδιά μπερδεύτικα από την περιγραφή της φωτογραφίας. Όπως και να 'χει όμως η φωτό είναι πολύ καλή.