IB20

I went a good few years ago and at the time felt it was definitely aimed at children. Lots of the interactive exhibits had been “child handled” and weren’t working. It was still interesting but I wouldn’t recommend travelling a great distance if you don’t have kids.

There’s a transit of Iapetus on the night of July the 17th/18th this year. Not sure what kind of aperture would be needed for observing this, could be a case of one for the imagers.

So it has taken a selfie… Incredibly, incredibly cool.

D is the diameter of the mirror and FL is the focal length, which I think is simply length of focus point from the surface of the primary mirror. If you divide the FL of the scope by the FL of an eyepiece you will get the magnification the eyepiece gives you.

What scope is that if you don’t mind me asking?

During this Jupiter season I was using between 80-106x most of the time in a 3” refractor. Could easily see shadow transits, barges, GRS, zones/bands. I remember one session where I can vividly recall seeing Ganymede transit against the planetary disc too. I never really found bumping up the magnification improved anything and always preferred sharpness over a softer view.

I don’t use binoviewers but it concerns me they seem quite impossible in this system. I’m annoyed that such an expensive piece of equipment isn’t perfect but then I remember even my £300 80mm achromat, with its 25cm of draw-tube travel, still struggled with in-focus.

I haven’t found anything that takes too much outward travel so far. The Delite requires more inward focus. My understanding is the Herschel Lunt wedge is too little inward travel as well.

This is a great help https://www.telescopes-et-accessoires.fr/Files/131989/FS-60CB_instruction_manual_EN.pdf It comes with an aux ring TKP20001 in the optical train but the schematics shows that for straight-through visual, so needs removing with a diagonal in place. Despite the really short draw-tube travel, I have been able to focus all my eyepieces with the Tak prism diagonal with the exception of the 13mm Delite, there’s a work around by moving it slightly higher in the diagonal though. I know @JeremyS found an adapter combination to get a Lunt Wedge and Quark working too but I haven’t had chance to do any white light observing yet. I think my next purchases for this are the 5XW Pentax and a micro-focuser, either the More Blue or MEF-3 upgrades.

I have the 76DCU for visual and I am enjoying it immensely. I’ve only had one chance to observe Jupiter, which wasn’t best placed but it has been outstanding on the moon, doubles, clusters and general perusing. It’s so small and light, I can’t quite get my head round how small the FS-60CB must be!

Clear but some dirty seeing here, high mags were swimming so have just cruised around Orion with the 17.5mm Morpheus in the 76DC. Highlights were two brilliantly red carbon stars of W Orionis and BL Orionis which are new targets to me. Open cluster NGC 2169 situated near BL Orionis too which is another wonderful target. Lost count of the number of double stars I stumbled on. Nice little session, sometimes we have to make the best of the conditions.

Our celestial neighbour amongst another hobby. Didn’t do us much luck 😅

Terrible seeing tonight here, lots of atmospheric rippling on the moon and Sirius is scintillating like mad. Struggling to push the magnification. Not worth pursuing as it’s too cold to wait around for conditions to calm down.

Seems I’m starting backwards on the L100! Have just noticed Lacus Timoris or the ominously sounding Lake of Fear, just to the left of Tycho, that was visible too. 😱

Superb @Nik271 thanks for this! I’d forgotten to flip my original image, I’ve lined it up with the simulator too. Pretty chuffed at seeing these craters! 😀

Had a look at the Southerly pole of the moon. I’m amazed at how good it looks in the Tak, the undulations, hills, cliff faces, recesses, valleys and features present with such definition, they are truly striking. Almost feels like I could walk along them. Two features stood out marked on the 2nd image. Any lunar experts help identify them as I’m struggling to find out what they’re called? Was extremely cold out so had a quick look at M42; sure I could see the E star pop out on occasion but it wasn’t as easy as a few nights ago. Back inside now 🥶🧊.

Fantastic. FLO will always be my first port of call when purchasing Astro gear. It’s great to know your employees will be paid fair wages for their labour.

I have added this upgrade on my 8” SW. It’s an amazing bit of kit making fine focusing a joy. One of my best Astro buys to date.

I really need to spend more some time observing the moon. That Nasmyth Phocylides crater clash looks fascinating. Maybe one day I’ll know the names of some of the more exotic and unknown features.

It’s a keeper for sure. The two systems are interchanging nicely, got the Tak on the Starbase tripod and currently using the Starbase finder on the Tak.

One of the biggest differences, literally, is the length of the OTAs. Being nearly 25cm longer than the Tak, it makes manoeuvring as a grab n go and observing higher altitude targets that little bit more uncomfortable and cumbersome.

Copied last night’s targets with the 76DC in Orion with the Starbase 80 tonight. Conditions and transparency seemed similar to last night but the moon was 6-7% more illuminated so there is that to take into account. After letting the scope cool for 10 minutes I started off with the 17.5mm Morpheus on M42 (46x) and honed in on the trapezium cluster - showing all 4 stars nice and clearly. Tried to match the lowest mag I used last night so swapped in the 25mm BST, again all four showed, but in both EPs I’d say the stars looked slightly dimmer than the Tak. There was also no sign of the E star after multiple re-visits, the 7XW also resulted in dimmer images purely due to the smaller exit pupil in the f10 system. Going through the mags, it was obvious that the nebulosity of M42 wasn’t as defined and contrasty as in the Tak, and it appeared as more of a smudge than the shapely wings I observed yesterday. Moving to Rigel, I got a nice split at 80x but the diffraction rings weren’t as well controlled and a small arm of CA and stray starlight tried to obscure the dim secondary, although visible it wasn’t the doddle it was in the Tak. Mintaka and Nair al Saif proved nice and easy splits and all stars presented clean airy discs. Betelgeuse however was a lot messier, nice colouration but just not as well controlled as the Tak. On to Sigma Orionis, the Tak showed all 4 stars easily yesterday and tonight the Starbase displayed all 4 but the lowest mag secondary companion occasionally dipped in and out of view. Finally, a crack at Sirius but presented with what seemed like a lot more diffraction rings coupled with a purplish glare, no where near as controlled as the Tak! I guess it’s not a surprise result, a £1200 premium fluorite scope being better than a £300-350 achromat, but not by much, there wasn’t a lot I didn’t see with both scopes. Look forward to comparing both under the same conditions when I sort out a nice mount and tripod for the Tak. The white light comparison could be really interesting too. If anything, tonight’s session reminded me how much I love this scope and it’s nice to have a grab and go I can use if I’ve had a beer or two.

Was terribly foggy around 6pm so decided to have a few drinks. It’s now crystal clear! Have quickly put the Starbase 80 out, I have a no drinking and Tak handling rule! 🤪 Will see what Orion is like compared to the 76DC

Super set. The 7XW is proving to be a wonderful EP. Think I’m going to save up for the 5XW next.

Spent most of the tonight’s session in Orion again with the 76DC. Rigel split easily with the 7XW, always worth a visit. Betelguese’s colouration was mesmerising, a perfect deep gold disc with such tight diffraction rings. Sigma Orionis showing four brilliant stars. Visited M42 numerous times and tried to spot the E & F stars with mags ranging from 81-178x but couldn’t tease anything out. A-D stars were showing beautifully at 32x & above however. Did leave Orion to gawp at the Christmas tree cluster, beehive cluster and after some star hopping, found the faint Eskimo nebula. Pretty washed out from the moon’s brightness but certainly visible. No doubt a good target for my dob next time I tear myself away from the Tak. Tried for comet 67P but again foiled by the moon I think. Bashing my head against a brick wall I went for Sirius again, a relatively still night but chimney trails were making it dance and weave. To finish the night I returned to M42, with the 7XW I could detect a really faint pinprick of light to the left middle between the A & D stars of the trapezium. Checking SkySafari the star was Struve 748, is this the E star? The contrast and control in the Tak 76DC is mind bogglingly good. I’m falling more in love with it with each use - I’m finding I’m spending hours on very few targets. I didn’t even look at the moon tonight 🤣