Stu

I was supposed to be getting an early start, working in the garage and garden today, but given the lovely sunshine this morning I thought it would be rude not to give the Beast its first run out which somewhat delayed me! As a recap, ‘The Beast’ is a 150mm f10 PST Mod using an internally mounted 110mm Baader D-ERF and setup to work with a barlow element in my Baader MaxBright II binoviewers and 40mm Plossls. Our very own Peter Drew kindly put the scope together for me and checked it worked with the binoviewers correctly. I mount the scope on my AZ100 Goto with a pillar on top of the Planet tripod. Whilst it suffers some vibration I reckon it will do the job, until I build a pillar and perhaps a dedicated mount for it. The scope itself is large, but not unmanageable weight wise. I can carry the mount and tripod in one piece out into the garden too, although my back doesn’t thank me for it! Back to the scope, it is designed for high power, hi resolution views in Hydrogen Alpha and will require excellent seeing to make the most of. Suffice to say, my expectations today were not that high, I thought I would have to wait for the Sun to get higher in the spring for this scope to be worthwhile. How wrong I was! Initially though I had problems finding focus, until I remembered to pull the PST backend out of the OTA to the correct distance and could then give it a tweak with the PST focuser. I also found eye positioning very difficult due to the long eye relief of the Plossls, extended further by the Barlow. I solved that eventually by resurrecting some home made eye guards which reduce glare from the side and make eye positioning much easier. So, the views? I guess I expected proms to be spectacular in this scope, so was quite unprepared for the contrast and detail on the surface features. In the 102mm, this is relatively muted compared with the proms, but in the 150mm it was quite gobsmacking, and the scary thing is, I know it can be so much better than this in better conditions. There were some nice proms visible, but that surface detail really stole the show. Filaments showed clearly, and there were two lovely filaproms showing in almost 3D as they arced from surface over the limb. This is a crop from today’s Gong image. Most dramatic though was the group of active regions 3536, 3537, 3539 and 3542. Hard to describe, so I’ve cropped the relevant bit out from the Gong image and processed it a bit to give you an idea, though the reality was so much better; contrasty and the bright parts quite dazzling. I need to dig out my solar observing book so I’ve got some language to describe these features properly. Anyway, I’m delighted to have finally got the scope back home, and to have seen that it more than meets my expectations. Best of all, I know there is so much more to come! With grateful thanks to @mikeDnight for the donor scope, @Highburymarkfor the D-ERF and of course to the legend that is @Peter Drew for creating this wonderful scope for me. Hopefully at some point I’ll be able to get it to a star party to share the fun!

Sorry to hear that @MalcolmM, it’s a sickening feeling when something like that happens. A while back, I picked up an eyepiece case that I was sure was clamped [removed word], but it wasn’t….. horrible, but fortunately no damage somehow. I would suggest replacing the WO binoviewers with MaxBright IIs! Clicklock holders and no messing about for collimation, they are just right every time.

Very nice! Thanks for posting as I missed seeing any of Jupiter last night due to inevitable cloud 😞

Yes, that’s what I’ve been seeing. The turbulence of the GRS seems to split the SEB then trailing it there is a dark band but at the bottom of GRS. @John’s sketch here shows it well I think.

The Beast in action for the first time today. Fabulous is all I can say, even though the seeing is not that great. Will write more later elsewhere.

I’m sure the AZ75 would handle either of these scopes with no problem. You have an excellent tripod and the mount is more than capable. I’ve used mine with an FS-128 and heavier LZOS 130 f6 and it was very useable. You may want to consider a counterweight, not because the mount needs it, just for stability of the rig but it may not be necessary.

FS-128 on AZ100 Goto/Planet. Looking at clouds mainly 🤪

Here is the FS-128 (aka Phyllis) on my AZ100 Goto with pillar and on a Planet tripod. I spent the evening largely looking at clouds, but had some decent views of Jupiter.

Typical! I’ve just let the dog out and the sky is now stunningly clear! We are in the middle of a film though, so no chance of going out now unfortunately.

Good stuff, cloudy here 😞 So, is Ganymede appearing bright or dark against the surface? Probably bright just to prove I was talking twaddle all along 🤣

🤞🤞🤞

There’s a fairly uncommon Ganymede transit coming up which I posted about a while ago. In theory Ganymede is a bit darker than Io or Europa so may show as dark against Jupiter and so be visible more easily during its transit. Cloudy here inevitably 🤬

Very nice John! Similar view to mine last night. The dark band off the bottom of the GRS is very distinct, isn’t it?

I negotiated a full evening pass last night as the forecast has looked promising a few days ago, but alas it was mainly cloud with a few clear gaps. I was trying the FS-128 out with the FeatherTouch FTF3035 for the first time, and it was a good as I hoped. So much easier to reach good focus with a lighter touch on the scope. Annoyingly I couldn’t find the power cable for the AZ100 Goto, so it was slo mos only which are a little bouncy with the motors fitted. In the occasional gaps I got, Jupiter was showing some good detail. GRS clear from the time it came around the limb, and when it was central the was a dark belt coming from the bottom of it. Plenty more to see, but it was fleeting in the better moments.

Andromeda is a bit of a weird one really. It is huge, roughly three degrees long by one degree wide, so to see it all you actually need a widefield refractor. Under a dark sky with a scope that fits it all in, it is a wonderful target. Big dobs by definition have longer focal lengths; even an f4 16” scope has a 1600mm focal length versus say 700 ish for a 4” refractor. Put even a 31mm Nagler in the dob and you get a 1.5 degree field of view, so you won’t fit it all in. Compare that with over 3.5 degrees for the frac example. What you do get is close up views which should show you the dust lanes but I think there are better targets for large dobs. Globular clusters in particular benefit from the added resolution and can be quite spectacular. Smaller galaxies are excellent too, under dark skies of course.

You have a very capable scope, despite its ‘beginner’ tag. I have owned one and it at times put other more expensive though smaller aperture refractors in the shade! Totally agree with what has been said already. Making a shroud should make a difference for a few reasons; it cuts out glare and protects the mirrors from few, but I also used to find that my breathing disturbed the views as it goes straight through the light path. Adding a shroud stops this happening and steadies the views. Whilst your scope won’t need that much cooling, it will still benefit from say 20 mins to let it acclimatise to the ambient temperature and stop convection currents. For some reason I never really spent much time on Jupiter with mine, but I got some excellent views of Mars with it when it was at opposition, dark markings and the polar cap visible which was a great result for such an affordable scope. I see no reason why you shouldn’t get some more detail out of Jupiter with practice. Keep your collimation right, get the scope cooled, observe when the planet is at its highest and as often as you can so you catch the good seeing conditions when they occur. Nail the focus, then just spend time at the eyepiece. Your brain is very clever and over time it combines the best moments of seeing so that you see much more after, say half an hour, that a short one minute look. There are plenty of improvements which can be made to the scope. Wrapping PTFE plumbers tape around the threads of the focuser helps give it a firmer movement and stay where you put it. You can also put the scope on a mount using the dovetail, which puts it at a much more convenient height. I never actually used mine on the dob mount, putting it straight on a mount. If you search for Heritage 130p posts by @Mark at Beaufort then you will find plenty of great examples of how to lodge scope to improve it, like this one: Enjoy! 👍

Was just about to post on this after seeing it on Sky News https://news.sky.com/story/new-images-reveal-neptune-and-uranus-are-not-the-colours-we-thought-they-were-13042392 I see Uranus as greyish green, and Neptune as quite a deep blue, definitely different colours so I find this quite intriguing. I wonder why what we see differs from this finding?

I normally use either a TelRad or Rigel Quickfinder to get in the right starting place, and then a RACI of some description, normally 10x60 to do the hopping. Sometimes I will just use a widefield eyepiece in the scope and not bother with a finder. Key to everything for me though is SkySafari. I know that phones can and do affect your night vision, but to be honest most of my observing is done in places where other sources of light affect me at least as much, so the benefit of using SkySafari outweighs the negatives. If I were observing in Mag 21 plus skies I would think differently. I have actually bought an e-ink tablet which can be set to very low, or no backlight so I will start to use this more as the weather improves. Another benefit is that my brain seems to work better with white stars on black, rather than the negative you normally get with printed maps. I set the app to show the same orientation and field of view circle as either the finder or scope, and set the limiting magnitude of the stars shown to match what I’m seeing. It then becomes trivially easy to hop from your starting star, just by matching patterns as you go. You can zoom out to see that you are heading in the right direction still and then back in again. Almost feels like cheating, but I’ve found some good stuff using this method, including from under quite light polluted skies where few stars are visible with the naked eye. So long as you can find a starting star you are in with a chance.

Thanks very much Mark 👍. Your ERF was one of the last pieces of the jigsaw that made it possible. It’s been a long time in the making; there as an idea in my for a few years then a while to get it organised and then seven months to be able to go a pick it up! Hopefully worth it though 🤞

Managed to get the scope mounted with a spare pair of rings whilst waiting for the correct ones to be delivered. It sits well on the AZ100 and seems pretty solid. I might give it a go in Astro mode first by refitting the original focuser and removing the D-ERF. This scope will need excellent seeing to give best results on the Sun, and that won’t be until it gets a bit higher next year.

Pretty sure it was a 4” refractor (Tak FC100) on a Vixen GP-DX mount, though may have been on the AZ100 tracking motors. I believe it stacks the subs and corrects for rotation if using an AltAz mount. I’ve got my AZ100 back now, so will give it another go soon (weather dependent!)

Thanks John. It is rather lovely. I find that a good dual speed focuser really improves the feel of the scope; you can have a much lighter touch with the fine focus which helps reduce vibrations.

If you count me as the postman, this beauty made it back to me today as I finally managed a trip up to see Peter and collect it from him; David had kindly dropped it off at the Astronomy Centre for me 👍. Now fitted, it looks and feels as fabulous as I expected, will make a big difference to my enjoyment of the FS-128, when we get some clear sky of course!

No hope here either, blowing a gale and chucking it down all afternoon and evening ☹️

I can’t quite believe where the time has gone! I finally collected this from Peter from Todmorden today and will be home this afternoon. Lovely to meet Peter finally and have a little look around the main dome with its 16” and piggy backed 150ED (which looked tiny!) Goodness only knows when we will get some sun, but hopefully when it gets higher in 2024 I’ll get to use the Beast and enjoy the fabulous views.