Ags

Actually, this new APM zoom looks a bit delumptious...

COMPLETE! Well, maybe I will upgrade the barlow, and maybe get a Baader zoom. Speers WALERs to the left, then Explore Scientific, and Vixens to the right.

Bonanza today. Proof copy of my book in hardback form with Amazon premium color - looks good. And two vintage NLVs from @Mr Spock.

Combined with the barlow, it looks like an ideal addion to my Zenithstar 66. At its widest it would give 1° fov, and at narrowest it would give 109x magnification. How does it hold up at F6? I used to have fixed focal length hyperions and loved them in a Mak, hated them when I got fast refractors and newts.

Two things put me off the Baader Zoom: the sortest focal length is only 8 mm, and the AFOV at 24 mm is only 50°. It might be useful to me with the 2.25 barlow, but how does the barlow affect the AFOV of the zoom throughout its range?

The best advice I can give is: don't eat the eyepiece and you'll be fine!

I can highly recommend doubles as an observing choice in Bortle 8++ conditions. If you can still view Lyra from your location, it has a number of lovely doubles near relatively bright stars - all very easy to find. You can download the PDF in my signature which has a number of finder charts. Cassiopeia is also a rich hunting ground with plenty of bright stars acting as signposts.

I do dream about dream scopes and I am glad they exist. I think if a future archaeologist digs up a Questar, they would smile at our folly and think more kindly of our barbaric culture!

I find my Wratten #8 quite useful when observing the planets, given their current low elevation and consequent atmospheric dispersion.

The high power eyepeices will show the middle of the field, so you will see less coma. But the focal ratio of the telescope remains very "fast" regardless of the magnification, and affects eyepieces of every focal length. Having said that, there are plenty of cheap "planetary" style eyepieces that work fine in so-called fast scopes. It's more of an issue for wide apparent field eyepieces.

I've backpacked with an ST80 and it is rugged and effective. If I was you and buying now I would buy the SkyWatcher equivalent of the SkyScanner for the aperture and novelty, and because the tube is red! One consideration with the SkyScanner is it is very fast (focal ratio of 4.0 versus 5.0 for the ST80) so it will be quite tough on eyepieces. The ST80 will have a lot field curvature (different focus point at the edge of the field of view compared to the center) while the SkyScanner will have lots of coma (towards the edge of the field, stars look a bit like comets). Both are capable and enjoyable scopes, but the SkyScanner gathers more light and can go to higher magnifications.

My 9mm and 12mm NLVs came second hand from the UK with a nice helping of VAT added at the border. But no soup 😐

I keep thinking I should get an SLV 2.5 for my ZS66, but I am waiting for a turret that works better than the Baader Q Turret. The eyepiece should help a lot with double stars!

I had a department store telescope as a kid - it must have had plastic lenses or been a singlet because the chromatic aberration was so bad, but it showed me Jupiter's oblate shape and its four moons, and also Alpha Centauri, so I was hooked. As a teen I tried making a 6" reflector but kept getting nasty scratches in the polishing stage. Life intervened for a few decades, then I got back into the hobby with a Nexstar 4SE.

I don't drive and wouldn't feel safe observing alone in some deserted spot, so all my observing is in my Bortle 8 back garden. This gives me access to a patch to the south, and a bigger patch to the east. West from the zenith down is blocked, and north is lost to the Amsterdam light dome (the southern patch gets blasted by the infernal Dutch greenhouses, but it is still good for planets). My observing season on any object is very brief - here in November, I read with envy of people still observing targets in Lyra! We are thinking quite seriously about moving to La Palma on a semi-permanent basis so I hope for better skies there. I hope I can persuade my employer. I haven't been in the office since early March last year, so I don't see why I can't labor for them under La Palma's skies instead! Even before the pandemic, my work was 100% about online meetings and giving remote assistance to clients around the globe, so really an office location is pretty irrelevant for me. I expect however there will be a housing shortage on La Palma for a while given the recent volcanic disaster.

The ZS66 was sufficiently warmed up after an hour so I took it out for a star test. Aside from a loss of sharpness from tube currents, the blue-red cross was still there. Out of focus, the rising tube currents looked like a lava lamp! So cool down is definitely needed, even for small fracs. After 15 minutes of re-cooling, the blue-red cross was confirmed, and clearly not related to scope temperature. After a brainwave, I removed the Baader Q Turret and used the eyepiece directly in the diagonal. Red-blue cross gone, point-like stars restored. That's a shame, I quite like the concept of the Q Turret, and the better turrets are a bit spendy...

The 50 mm RACI has popped up several times on this thread. It has been revolutionary to me.

@Mr Spock one thing about your table. How stable is it? It looks like a bump from the left (in your picture) could send the eyepieces scattering. Regarding picking up the orthos: it would take a bit of work to make it look nice, but add a ring of wood around those holes to raise the eyepieces 5 mm?

Slightly off topic, but what about other strong colors. I have seen strong oranges and yellows, but a good blue is really elusive. Alnitak should be the bluest of blue (being an O type star with high apparent brightness), but it just looks white to me. Maybe "cold white", but that's all.

Tonight I saw a confounding peculiarity. My Zenithstar was bringing stars to focus not as a dot but as a sharp blue line forming a cross with a sharp red line. What is the meaning of this annoyance? It wasn't the eyepiece (an excellent SLV 6) as the same sight was revealed in my ES 6.7 too. My working theory is that the telescope was too cold and the the lens cell got pinched. I put it out to cool down at sunset, on the basis that I've always owned Maks and SCTs and three hours of cooling is what you do. It's a relatively mild 3°C tonight so not that cold surely. The scope is indoors warming up for a test session later. Never seen this effect before... Hopefully it is just my Mak-based cooldown routine. I can switch to a no-cooldown routine instead I think given the aperture is just 66 mm and the light isn't folded threefold through the tube. On a more cheerful note, I was wearing my distance vision glasses, and the Moon looked spectacularly sharp (no telescope).

The first question is, what would the upgrade fix? Are you chasing the last 5% of on-axis performance, or do you want generous eye relief? Then SLVs. Do you want excellent performance with an ultrawide field of view, then ES 8.8mm. If there is nothing in particular bothering you about the performance of the Starguiders, stick with them 🙂

Nice work. I simply put this on a regular table 😀 one advantage of this is I can keep the lid shut with a hand warmer inside. No dewy eyepieces! It needs a red light that comes on when open.

If it is for low magnification views of big stuff like the Pleiades and M31, then a StarTravel isn't a bad idea. I used to use an ST80 for the same purpose and it was capable of giving lovely views of those sort of targets.

Yes, it must be Petavius. Very striking.

I want all of them!