Apollo

The first of the so-called 'J Series' missions, geared for maximum scientific gain, Apollo 15 took the first car to the Moon the LRV or Lunar Roving Vehicle. The landing was made on July 30, 1971. At last, the astronauts could cover many miles on the lunar surface. Of all the Apollo landing sites, the Apollo 15 Hadley rille region is the most fascinating to inspect through an amateur telescope and the most infectious to webcam. Lying 200 kilometers southeast of the 80-kilometer crater...

The Solar System A Brief Introduction

This is primarily a book about imaging the planets with webcams and is aimed at amateur astronomers who already have some basic knowledge of the solar system. However, we all have to start somewhere and it is quite possible that a few complete beginners will be attracted to this book, with virtually no prior knowledge of astronomy at all. This chapter is for the total novice. If you are familiar with the structure of our solar system, feel free to skip this introduction. If not, then start your...

Planetary Webcams and Their Alternatives

Imaging technology is a very fast moving area in the early 21st century. Once millions of dollars are invested into any form of technology, fueled by public consumption of a product, remarkable advances can occur. In 1989 the very first amateur CCD cameras started to appear on the market. A decade later, the first decent digital cameras and webcams started to be mass produced. In 2004 2005, Canon's Digital Rebel 300D Digital SLR put a real SLR camera in consumers' hands at a very affordable...

Keen Planetary Observers

Damian Peach's excellent planetary imaging page www.damianpeach.com Antonio Cidadao's lunar and planetary imaging http www. astrosurf.com cidadao Eric Ng's planetary images www.ort.cuhk.edu.hk ericng webcam Ed Grafton's planetary page www.ghgcorp.com egrafton Dr. P. Clay Sherrod (Arkansas Sky Observatory) www.arksky.org Jesus R. Sanchez www.arrakis.es stareye Tan Wei Leong's planetary images html Martin Mobberley's web pages Christophe Pellier Thierry Legault's high-resolution imaging...

Quality Equipment for Planetary Observers

Cloudy Nights Equipment Reviews www.cloudynights.com Celestron www.celestron.com Celestron's U.K. dealer David Hinds www.dhinds.co.uk Orion Optics (U.K.) www.orionoptics.co.uk Takahashi Home Page (Japan) http www.takahashijapan.com Texas Nautical (Takahashi U.S.A.) www.takahashiamerica.com True Technology (Takahashi U.K.) www.trutek-uk.com BC& F Telescope House (U.K.) http www.telescopehouse.co.uk TEC (Telescope Engineering Company) http www.telescopengineering.com TMB (Thomas M. Back)...

Brilliant Venus

As far as the planet Venus is concerned, many of the factors that affect observations of Mercury are similar for Venus. It too orbits the Sun within the Earth's orbit and it is rarely high above the horizon after sunset. Like Mercury, it is biggest when merely a thin crescent (or when transiting the Sun) and it is best when elongated as far from the Sun as possible. Venus is the planet most similar in size to the Earth. It has an equatorial diameter of 12,104 kilometers, i.e., 95 of the...

Copernicus [97 N 2GG W

Copernicus (Figure 10.19), situated in the Oceanus Procellarum, must be the most obvious crater on the Moon to the binocular user. Although it is certainly not the largest lunar crater, it is situated close to the center of the disc and away from any Figure 10.18. The crater Gassendi and the intricate rilles on its surface. Orion Optics 250-mm f 6.3 Newtonian and 5x TeleVue Powermate. September 9, 2004. Image M. Mobberley. Figure 10.18. The crater Gassendi and the intricate rilles on its...

Clavius [584 S 144 W

It is tempting to think of Clavius (Figure 10.11) as the largest crater on the near side of the Moon. In fact, this is not the case. But, undoubtedly, it is the largest spectacular crater on the lunar surface and it is a truly awesome sight. Larger, Figure 10.11. An excellent image of the huge crater Clavius, taken with a 250-mm f 6.3 Orion Optics Newtonian, working at f 24. Image taken with an ATiK 1HS webcam on March 19, 2004. Image Jamie Cooper. Figure 10.11. An excellent image of the huge...

Test Objects

A number of lunar features have become test sites for a telescope's resolution. Probably the most famous features in this regard are the tiny craterlets on the floor of the crater Plato (shown later in this chapter in Figure 10.21), the rilles near the Figure 10.1a. The major lunar seas. Key (clockwise from top) Nu Mare Nubium Hu Mare Humorum In Mare Insularum OP Oceanus Procellarum Im Mare Imbrium SM Sinus Medii Fr Mare Frigoris Va Mare Vaporum Se Mare Serenitatis Tr Mare Tranquillitatis Cr...

Thermal Considerations

If someone were to tell you that having an electric fan on a telescope was, perhaps, the most important decision you would make in your observing career, you would probably brand them as insane But, as the years have gone by (and I have been observing planets for over 30 years) I have become increasingly convinced that the ability of a telescope to cool to the night air is absolutely crucial to getting good results. Back in the 1970s, the French optician Jean Texereau claimed that a temperature...

Plato [516 N 93 W

We have already looked at Plato's smooth, dark floor with regard to resolving the tiniest craterlets, but Plato (Figure 10.21) is a fascinating crater in its own right. With such a smooth floor and such high mountain peaks on the eastern Figure 10.20. Brilliant Aristarchus, plus Herodotus and Schroter's valley, imaged with a 37-cm Newtonian working at f 14. Starlight Xpress HX516 CCD camera. A single 0.01-second exposure taken on March 29, 1999. The inset shows how the subtle banding on the...

Find the USB Port and Buy a Webcam

The first step on your webcam journey is to check that you have a PC with a USB port. If your computer was made before 1998 it may not have one, in which case there is not much point proceeding. A USB port looks like a small slot in the PC and is completely different in appearance from the multi-pin serial and parallel ports. In addition, if your PC's operating system is earlier than Windows '98 then USB will not be supported. PCs and operating systems prior to 1998 simply will not work with...

Webcam Imaging the Giant Planet

Compared to Venus and Mars, Jupiter is not a planet with a high surface brightness. Yes, it is bright in the evening sky, but that is mainly by virtue of its physical size. However, it is much brighter than Saturn and, crucially, more than bright enough for a webcam to easily record, even with brief 1 10th second exposures that freeze the seeing. The biggest problem with Jupiter is the speed with which it rotates. As we saw earlier, the formula to calculate the 0.5 arc-second drift time window...

Gamma

Many terms used in planetary imaging are already in frequent use by nonas-tronomers. The digital camera era has plunged many otherwise sane and normal people into the world of image-processing jargon. However, the term gamma is rarely understood and it is so crucial to planetary imaging that an explanation is required. At first glance it would appear that increasing the gamma of an image makes it brighter and reducing the gamma of an image makes it dimmer. However, it is a lot more subtle than...

The Lunar Limb

On a final note, before we leave lunar orbit, I would like to say a few words about observing the lunar limb regions. It is often said that there is little point observing the Moon when it is full, simply because there are no long shadows and the finest details are always glimpsed when the Sun is very low over the formation being studied. Thus, at sunrise and sunset, maximum contrast is seen. At full Moon, the regions on virtually all the visible lunar disc are experiencing the Sun well above...

Saturns Weather and the Great White Spots

To the beginner, Saturn's globe appears fairly featureless when viewed through the eyepiece. Although Saturn does have equatorial, tropical, and temperate belts and zones (Figure 14.1), there is nothing on the disc that stands comparison with the Jovian Great Red Spot or even the giant planet's North and South Equatorial Belts. Undoubtedly, the huge amount of internal heat produced by Jupiter, combined with its closer proximity to the Sun, is responsible. Heat is the driving force behind...

Alpha Imagin

When you first look through an H-Alpha filter you will be struck by the deep red color of the image. It is immediately obvious that this is a redder red than you see in everyday life, and the color may be a bit off-putting at first. However, this is no problem for the CCD detector in a webcam, which is very sensitive at 656 nanometers. A monochrome webcam like the ATiK 1HS is the best choice as it is pointless using a color webcam for such narrow-band work. However, digital SLRs, and even small...

Space Probes And Hubble

As well as observing the planets out of sheer fascination and actually seeing them with your own eyes, the images returned by planetary space probes throughout the last few decades have been truly staggering and are well worth tracking down on the web. While manned spacecraft have only traveled as far as the Moon, unmanned robotic spacecraft have traveled to every planet except Pluto. Traveling at speeds as fast as 60,000 kilometers per hour (17 kilometers per second), these probes still take...

Advanced Stacking of Rippling AVI Frames

We have already examined the remarkable Registax software developed by Cor Berrevoets, a software package that has made the stacking of thousands of AVI frames a routine and reliable operation. However, few amateurs who use Registax seem to have the spare time or the inclination to examine exactly how it works and to assess which options are the best in different situations. However, a full understanding of Registax' strong and weak points can be of great use. As a Registax user myself, I hope...

Collimation

Maksutov Collimation

I never fail to be astounded at the number of amateurs who do not keep their telescopes collimated. I wonder whether they are simply scared of doing more harm than good, or even damaging the instrument. Admittedly, the traditional methods of star collimation are best done with two people, but, for the webcam user, this is just not necessary. It must be said that not all telescopes, even expensive ones, have friendly mirror adjustment systems. I know of one world-class planetary imager who...

Ultimate Planetary Telescopes

What is the ultimate planetary instrument Is there such a thing at all and what, exactly, do we mean by ultimate I have touched on this subject already when discussing the relative merits of my own Newtonians and the long-focus Newtonian. One way of answering this question is simply to look at what telescopes the world's leading planetary imagers use. However, when we do this we just see a reflection of the market share of different telescopes. Damian Peach,...

The Deep Red Advantage

At first it might not be clear how the LRGB technique can be applied to curing atmospheric dispersion. Surely, in the luminance image, the full dispersive smearing is still captured, but is it simply a monochrome smearing Well, this is true, but Figure 8.3. Once LRGB processing is checked, the LRGB sliders in Registax allow the luminance signal to be constructed from any mixture of the color channel signals. Figure 8.3. Once LRGB processing is checked, the LRGB sliders in Registax allow the...

Holiday Destinations

Of course, a lot depends on where you actually live an amateur astronomer in the U.S. is unlikely to prefer a Mediterranean destination to a Caribbean one unless he or she wants to combine a European north African sightseeing trip with a bit of astronomy. The requirement is, of course, to head closer to the equator so that the planet is higher up. Also, a site that enjoys clear skies much of the time is essential, as is a site renowned for its good seeing. As we are planning on heading nearer...

The Martian Moons

A real challenge for the amateur observer, even at a favorable opposition, is spotting the Martian moons Phobos and Deimos. In a large amateur telescope these 11th and 12th magnitude moons would not normally be a challenge, but they never stray far from the brilliant Martian disc and their rapid orbits mean they move considerably even in one night. Phobos is the larger Moon at over 20 kilometers across but never strays more than a Martian diameter from the planet, making it the hardest to see....

Quick Start Guide

This Quick Start Guide is designed for those people who have limited knowledge of webcams or image processing but are comfortable with PCs and gadgets, have a telescope, and just want to get up to speed quick. In other words, they want to get some good lunar or planetary images in the next few days, without studying every chapter of this book. If you fall into this category, this section is for you. Assuming you have a USB-equipped PC newer than 1998, you need to have the following, all of...

Equipment For The

On a planetary imaging trip you will need to cart several thousand dollars worth of fragile equipment to your destination so, the first point to note is that you will need adequate travel insurance. Your basic insurance will almost certainly be inadequate. Also, when observing far from home, you cannot suddenly dash indoors to get some vital piece of equipment if a problem arises. Therefore, some forward thinking is highly advisable. Note well the bits and pieces you use at home before you fly...

Final Processin

The Wavelet page is, undoubtedly, the Registax page where really excellent images are created. This is where you can endlessly tweak, tweak, tweak, tweak, tweak the image until you are diagnosed as having an obsessive compulsive disorder and the men in white come to take you away. What in God's name is a wavelet anyway Well, the term wavelet originates from the world of DSP, or digital signal processing. In electronics, as well as in planetary imaging, the challenge is often to extract signal...

Dispersion

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...

Image Scale Considerations

Let us have a look at this image scale business in more detail because it is important to understand the issues involved. Most of the popular webcams have CCD chips with an array of 640 x 480 pixels. These pixels are, typically, 5.6 microns in size. So the imaging chips themselves are roughly 3.6 x 2.7 mm across. The standard formula for calculating the resolution of a telescope, in arc-seconds, is given either by 138 D (the Rayleigh limit) or 116 D (the Dawes limit), where D is the Figure 7.2....

Ptolemaeus [92 S 18 W Alphonsus [134 S 28 W and Arzachel [182 S 19 W

Lying exactly on the lunar meridian, but trailing south from just below the center of the disc, one will find three impressive craters named Ptolemaeus, Alphonsus, and Arzachel (Figure 10.27). The trio is so distinctive that it is almost impossible, even for a beginner, not to recognize these three huge craters. Ptolemaeus is the Figure 10.27. Ptolemaeus, Alphonsus, and Arzachel. Imaged on April 9th 2002, with a 37-cm Newtonian at f 14 a ToUcam Pro Webcam. Only six frames were stacked for this...

Saturn through the Webcam

Saturn Images Taken Philips Webcam

Saturn is the most challenging and, arguably, the most rewarding target for the webcam imager. The biggest problem posed by the ringed planet is simply its low surface brightness. Saturn's globe is 16 times fainter than the globe of Mars and a third as bright as Jupiter. With the maximum available AVI video exposure being 1 5th of a second (5 frames per second at, confusingly, the 1 25th setting on the Philips driver settings) and 1 10th being more desirable (to freeze the seeing) the raw...

Video Options

Webcams are not unique in their ability to freeze the atmospheric turbulence. For many years before the webcam, low-light video and security cameras where used to freeze the seeing, with the added advantage that data can be stored on videotape. In 2005, this data can be stored on a variety of tape formats and on DVD as well. Indeed, the two technologies are now merging, as domestic video recorders featuring terabyte hard disks are now on the market. This book is about lunar and planetary webcam...

Predicting The Atmo Calms

The popular concept of an astronomer's perfect night is one where a cold front has swept through the observer's location and a crystal-clear sky full of twinkling stars can be seen. In fact, this is a nightmare scenario for the planetary observer. A cold front passing through a region may well reduce the moisture content of the air and is great for looking at deep sky objects and comets, but it leaves the air in a very unstable state and, invariably, the hotter ground radiates its daytime heat...

Optical Quali

250mm Newtonian

A word or two here about optical quality may be appropriate. Manufacturers quite often use the term diffraction limited. This means that the optics are good enough that they are only limited by the laws of physics, and the property known as diffraction limits the resolution of all instruments, whether optical or radio telescopes. The larger the mirror is in relation to the wavelength, the better the resolution you will get. To be diffraction limited, an optical telescope needs to have optics...

Planetary Imagers Worldwide

250mm Newtonian

Despite the ease with which excellent planetary images can now be obtained, planetary imagers are rather thin on the ground among the population. Across the world there are only a few dozen regular planetary imagers whose results are good enough to be used by professional astronomers. Undoubtedly the main reason for this is simply the rarity of good, stable, atmospheric seeing coupled with clear skies, along with the dedication and knowledge required to get world-class results. However, a few...

Saturns Rings

As well as Saturn's rings and the Cassini division providing an excellent sharp edge on which to focus, they also act as a great seeing indicator and can be used to check the color balance of an image. Let us look at the ring structure in more detail. The Pioneer 11, Voyager 1 and 2, and Cassini spacecraft all showed that the Saturnian ring system is highly complex. Fortunately, the view through the amateur's telescope is a lot simpler and basically boils down to a system of three rings,...

Astro Webcam Manufacturers

In the last few years a number of custom companies have sprung up in response to the need for affordable CCD imaging for those amateur astronomers with a tight budget. In many cases the products offered have simply been modified webcams, altered by a few wiring changes such that long, if noisy, exposures are possible, making webcams suitable for deep sky imaging. By stacking hundreds of frames, the noise has been reduced to acceptable levels for exposures of 30 seconds or so often the unguided...

Mercury Map By Mario Frassati

As was the case with my previous two Springer books, I am indebted to the outstanding amateur astronomers who have donated images to this new work. I feel humbled that such great names as Isao Miyazaki, Damian Peach, and Eric Ng to name just three have been so willing to share their images with others via my Webcam User's Guide. I am especially grateful to Damian as he has donated more images than anyone else to this work and it is only by his example, from the cloudy UK, that I was coaxed back...