mikeDnight

Ten PM would be too early from my site, as the planet would be low and troubled by heat from the town. The best is yet to come though, as Mars rises earlier each night, although it would still be worth staying up late so as to observe it high in the sky and close to the south Meridian. Regards, Mike

A turbulent sky or even tube currents will kill it every time. I seriously doubt you're an incompetent observer though Rob. And of course its good to remember that the detail in any sketch isn't how it first appears through the eyepiece, But an accumulation of detail recorded after around 15 mins of concentrated observing. I reckon a pencil and sketch pad can improve the performance of any telescope! Regards, Mike.

I'd consider a canvas garden bench cover Paul. I used a canvas garden chair cover for five years to cover my Losmandy mount and electronics in all weather's. Nothing ever got wet!

Thanks Des. I must be losing it big style as I had a seriously delayed reaction to the "out of this world" quip. It's so bad it made me laugh out loud once it clicked.

It's little wonder I'm so grumpy and have bad back, I've been doing it wrong all these years!

The P means preceding, which is the direction the planet drifts across the field of view. Rotating the diagonal can confuse matters though. If the diagonal was vertical, the south pole would be at the bottom with the terminator (the preceding side in this sketch) towards the left, even though the planet is moving to the right across the sky.

Amazingly the sky was clear and Mars was blazing brightly as it rose in the east before midnight. I set the refractor up on its mount, rolled back the roof of the observatory and aimed at the planet, not expecting too much. The seeing in my eastern sky hasn't been too steady of late, but tonight was different. The planet was immediately sharp, and the southern detail was well defined without having to wait for the scope to cool. After sketching the Southern hemisphere I'd become more aware of the more subtle detail extending from under the northern cloud and mists around the limb. The CM shows Solis Lacus to be on view and that's what appears in the sketch. Although I've observed this region many times, it nearly always presents itself in a slightly different light, which fascinates me. The view in the sketch is reversed as seen through a diagonal, and as the diagonal was at a tilt, I simply drew it as I saw it, so south is at 2 O'clock on the disk. I apologize if this messes with your head!

Another nice sketch Chris. I've not had much joy over the last few nights, but I've just had a great view of Mars this evening (9th sept), nicely displaying Solis Lacus, an asymmetric polar cap and plenty of limb haze. I made an eyepiece sketch of which I'll make a cleaned up version tomorrow. Regards, Mike

In a thermally stable refractor the focused star at 100X should present itself as a perfect Airy disk, appearing somewhat like a tiny pingpong ball, which if bright enough should show a single concentric diffraction ring encircling it. Inside and outside focus, the star image should appear as concentric rings either side of focus. If one side of focus shows no rings, that's a sign of spherical aberration. If the in focused star image appears furry around its edge, or the diffraction rings are washed out, this too indicates spherical aberration. Aiming the scope at a bright star such as Polaris and removing the eyepiece, then using a fine toothed comb held against the focuser, you'll see dark lines set against the starlight. Winding the focuser slightly inside or outside of focus until you see five lines, you can check the basic figure of the lens. A refractor should show the lines as straight. If there's any barreling of the lines the scope has spherical aberration. If the lines appear straight the scope is spherical and essentially perfect. In short, if the stars are sharp points of light the scope is good. If they are soft then you may have a problem.

I bought a 120 F8.3 Helios refractor back in 1999 and really enjoyed it. I remember vividly my first thoughts as I aimed it at a crescent Moon - "where is the false colour"? Obviously it was there, but it wasn't as destructive or as obvious as I'd expected. At F8 the 120 is still a rich field refractor and capable of giving some wonderful views of brighter DSO's. Personally I feel it has a performance edge over the F5 version, and yet it's still easily mounted and carried around. The only thing to be aware of with the SW's is that they are not all well figured, and can suffer from quite severe spherical aberration. On the other hand some are really quite wonderful. I suppose if you get a poor one, you could always return it and get a replacement.

A lovely sketch Robert. I hope you continue sketching as it makes a great record of your observations that you can look back on for years to come.

This is an interesting question Mark. I've mulled this over in my mind many times as different planets do handle magnification differently. For me, Jupiter is the most complex planet to observe. It's belt and zone detail is so complex and often so subtle, that over magnifying kills definition and contrast. So Jupiter will often give its best at around 180X no matter what scope is used. Saturn is full of fine linear detail, which appears sharp at higher powers, so 200X to 250X. Mars and Venus display more subtle albedo markings, and because the disk's are bright, the markings can be difficult to discern. It may seem counter intuitive, but smaller apertures can often give detailed views of Mars while in larger apertures the brightness can blind out detail. Personally i find Mars and Venus the most rewarding planets to observe, possibly because they are a challenge. Jupiter, although dynamic and highly detailed doesnt excite me too much, and Saturn sits between the two extremes as far as being an interesting target. When it comes to the planet's, a sharp image is essential, or at least as sharp as possible, so scopes that take an age to cool or that are sensitive to seeing can fare less well despite having larger apertures. In the end its all about how well a scope defines an image, so magnification needs to be tailored to suit both the scope and the local seeing, as without definition aperture is of no value.

The Pleiades are also affectionately known as The Seven Sisters, because visually with the unaided eye most people can count seven stars in the cluster. Some from a dark site can count more stars, and if the sky is transparent the entire cluster is bathed in nebulosity. ...The Pleiades, rising through the mellow shade, Glitter like a swarm of fireflies Tangled in a silver braid. -From Locksley Hall by Alfred, Lord Tennyson. Below- a sketch through a 4" refractor.

Fantastic! Your quick eyepiece sketches are a delight to me, and they reveal much more than the detail on view. They reveal that you have an excellent observing eye, and the ability to record what you see in a wonderful and meaningful way. Excellent!

You might be laughing, but your observing skill is undeniable. Many people struggle greatly with Mars and some see little or nothing at all. You though have captured detail beautifully. I hope you keep sketching it throughout this apparition and end up with a great visual record to look back on. EXCELLENT!

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That's an excellent image Lamaule. Welcome to SGL! I observed Mars last night visually and made a sketch, but in less than good conditions as the seeing was very turbulent. Your image though has confirmed some of the subtle detail I saw in the northern hemisphere. Can you remember the time of your image in UT? I think our meridians differ slightly but much of the detail is the same. EXCELLENT!

Superb image of Mars Simon. Absolutely wonderful!

I nolonger have the AZ5 and can't remember if the azimuth behaved like yours does. I do remember that I had to make some adjustments to the azimuth. I even had to strip it down and regrease it, as the drive was dry and squealed when in use. It made me think that the Chinese factory just assembles them rapidly without too much care, and its upto the purchaser to iron out any minor issues. I do remember the mount ran smoothly once I'd finished fine tuning it.

This is what I love about studying Mars Lee. It is challenging in so many different ways, as its small, brilliant and it's albedo features appear to alter shape and intensity. Mists and dust storms can alter the impression these features give, sometimes leading you to doubt your observations. But if every time you draw what you see then your observation is an honest representation of the view through the eyepiece, and that's all you can do. If you regularly sketch Mars throughout the apparition you'll undoubtebly have a number of sketches that don't appear to make sense at first. However, when you line up all your sketches in unison at the end of the apparition, everything becomes much clearer as you'll see Mars come to life, revolving on its axis. Nasa maps are of limited value to a visual observer as we rarely see anything but albedo features. Large impact craters such as Hellas and Argyre, may be seen well when highlighted by the mists within them, and Olympus Mons can be seen as either a bright or dark spot depending on whether its capturing cloud. Still, most of the markings are relatable to actual upland or lowland features. I genuinely thought your sketch was really good, which tells me that you have a keen eye for observation and the skill to record the detail you see. I'm looking forward to more of your sketches as the months progress and mars appears at a more sociable time. ☺

With my AZ5 i could gently tighten the azimuth locking nut until it allowed both the slow motion to work, and sill allow me to push the head round with the scope attached. But if the locking nut was loose the drive didn't engage. From what I saw in your video the mount seems to be working ok. You may feel the need to fine tune the tension on the worms by adjusting the grub screw on the drives. Often these Chinese mounts are not factory adjusted, they are just assembled and shipped out.

Your DL looks perfect on your T-Rex John. I can't imagine a nicer Altaz mount, its just a shame they are nolonger available.

Another great sketch Chris. I like your depiction of mists along the limb. Keep em coming, I'm loving it!

Its great to see such an excellent observation and sketch Procky. The dark patch in the north may well be Phlegra, as it corresponds nicely with the meridian on view.

I like the SW100ED and have owned one, but the TS being physically shorter would be my choice, as it will still do everything the longer SW will do and give a wider field. Could be a perfect grab and go scope!