Ags

I agree the eye relief is far too tight for me at the 3-5 mm settings, but I simply hover my eye a little higher and sacrifice the edge of the FOV. As a 60° eyepiece, the Svbony 3-8 has dreadful eye relief, but as a 45° eyepiece it has brilliant eye relief 🙂

I'm glad the price is going down, but I don't really regret buying earier either, the eyepiece has given me a lot of fun. At the current price level I think it is an instant recommendation for any beginner with an f4-f8 scope. I have been through plenty of eyepiece iterations over the years, but now I m starting to wonder if all I need right now are the Svbony 3-8 for general viewing, my ES 68 degree 20 mm for widefield stuff, and my SLV 25 mm for solar viewing and finderscope duties. Can it really be that simple????

I think just wipe it away, don't want to use solvent if not needed. I have a degree in Chemistry, and the only thing I really learnt is to not trust chemicals, especially ones you can breath in.

If I was being scientific I would move the wire, put it back together, wait three weeks for a clear night and test - before attempting any more changes. Life's too short for that! I can see some swarf in the current grease, so I will clean and regrease. On second thoughts maybe I should cut the red wire? Then it won't explode...

The internet is wrong. The AZ-GTI cover is held on by 4 not 6 screws. Already found the problem? Look at the red wire looped through the RA motor gear housing at the bottom... The innards revealed:

I'll keep a little photoblog of my mechanical adventures. Firstly my tools: Torch - to help my aged eyes 1.5 mm allen key - for grub screws Small star screwdriver - to remove cover Hammer - to fix it real good

Welcome back!

I should get an astrosnorkel to go with my astrohood?

Svbony 3-8 zoom and 90 mm refractor out tonight looking at some easy targets. I started with Jupiter, very stable and clear and no GRS as usual for me! I tried star-hopping to 21 Lutetia but my finder chart needs to show stars half a magnitude fainter to be usable. I also might pick up an Amici diagonal for this kind of detailed star hopping. I tried the zoom on Castor - it fun zooming in and seeing the split widen and the diffraction rings come into view. The zoom gave a nice view of M37 at 8 mm. I tried using a dark hood to help my night vision, but it had the opposite effect - the hood ws nice and dark but the longer I looked the fainter the cluster became. The hood was trapping my breath and fogging the eyepiece!

Not sure, I thought the astrofi was an alternative to eq5+150pds. Hopefully the OP can clarify.

I use a 6" SCT scavenged from an Astrofi 6 with an AZ-GTI mount. The telescope is excellent, no different from any other Celestron 6" SCT, and can be used for imaging planets and the moon (and even deep sky objects if you get an f6.3 focal reducer/corrector). I have no experience of the Astrofi mount, but I am pretty sure it would let you image planets or the moon, but would be a real headache trying to image deep sky objects which need longer exposures and thus a more stable platform.

I remember when I started back in the hobby a couple of decades ago that Jupiter was just a painfully bright, featureless disk in my 102mm scope. One of the mistakes I was making was waiting to be dark adapted - firstly your night vision doesn't have any sense of color, and secondly of course dark adaptation makes the planet seem too bright. These days I actually keep the outside lights on when looking at planets, and periodically glance over to my brightly lit porch just to make sure I am not dark adapting. Another thing to avoid is too much magnification - this simply makes the planet dimmer and colors more muted. I would expect the 4mm eyepiece would be too much for many observers. A 10mm eyepiece would be my choice I think... One final thing - when Jupiter is in focus, the planet's disk will be at its smallest size. If you turn the focuser and the planet gets bigger, you are moving away from best focus.

The GTi is pretty old so I can imagine the worm is riding up and down due to old grease. Can anyone recommend a suitable silicone grease? One video I found recommended vaseline, but I think maybe not...

A 4SE was my only scope for 10 years. There's plenty to like - sharp optics, no collimation hassles and reasonable goto.

That's a good tip, and very encouraging too!

Reading that thread is a bit depressing. It looks like I was lucky that my GTi didn't develop mechanical problems until it was a few years old. But it's always had electrical/software issues with DEC runaways while tracking, especially when pointed closer to Polaris. The only way to look at Polaris itself was to switch off the mount. It looks like the issue could come from the following areas: 1. Inside the motor. Unfixable. 2. The gears connecting the motor to worm. Clean, inspect and regrease. 3. The worm. Clean inspect and regrease. 4. The binding of the worm with the RA wheel. Tighten the connection when reassembling. 5. The bearings in the middle of the RA wheel. I'm tempted to say that's unfixable. Given the frequency and consistency of the ticks, I am inclined to discount 5 - that part moves too slowly to produce the ticks that frequently. By the way, I don't actually hear the ticks - I only see them.

Das ist eine gude tipf! I only frequent the te-les-koop.nl but the German market is obviously bigger. First thing I spot is an old EQ5 with motor and polar scope for EUR 210 😀 I have been pondering my situation for a while and I have settled on getting an EQ5 with dual axis drives after all. It will be perfect for all my current scopes. If I do decide to go big, I think a 10" dob on an EQ platform can always be added later.

Possibly they become self-aware and try to communicate in morse code?

I am the proud owner of two AZ-GTi mounts, but one is sadly useless. Every second or so it 'ticks' by an arcminute or two. Tracking is fine but the the constant ticking and ensuing vibrations make it useless for visual and photography. The ticking occurs in AltAz mode and in EQ mode when tracking so it's safe to say the issue is in the RA assembly. It is also super regular so its not sticky grease, its something with a pretty precise cycle of just under one second. I have looked at some vids about tuning AZ-GTis and they look a bit worrying but doable, but the question is - where is the fault likely to reside? Does anyone have any ideas what could be jumping, catching or slipping at a 1-second interval? In case anyone asks, the mount is out of warranty so I have nothing to lose!

I had 15 minutes of clear sky tonight, so I pointed the hackstrograph at the Pleiades. I haven't fixed the AZ-GTi yet, so the view 'ticks' every second or so. As a result I shot 333 ms subs while the gap in clouds lasted. Despite the short subs, I still had to throw away 75% of the subs - I would have had more keepers switching off tracking of course but I wanted to see how it would handle tracking and the goal was just to check how flat the field would be on my ASI485MC so I didn't need to gather a lot of light. The mount did track well despite the slightly higher elevation of the Pleiades... I am quie pleased with the stars at the edges, but I need to find my Astronomik L3 filter to improve the bloaty blue stars.

The Svbony 3-8 lives in the focuser of my small refractors. At the wide end it gives a bit more than 1 mm exit pupil and a 1 degree of FOV, so perfect for 99% of DSOs, and the zoomed function takes care of doubles, the Moon and planets. I also own a bunch of NLVs and SLVs and they win on comfort by a big margin. If I am taking a good long look at something, I would rather use my SLV 6 or NLV 9. I would say they give a better view too, cleaner and more contrasty. Despite that, the Svbony 3-8 is the one in the focuser.

I'm 40 years into this hobby and tonight was the first night I polar aligned. Only very approximately as the clouds were almost continuously blowing through the polarscope view. But I confirmed I could contort into a position to look through the polar scope and could make out Polaris in the scope, so progress! My old AZ-GTi was making its first outing in EQ mode, and I had slight hopes that the periodic judder the mount makes every second would not occur in EQ mode (50-50 odds as only one motor would be engaged). I need more counterweights but it turns out the AZ-GTi could track the Moon despite the misbalance. The hackstrograph itself is a Long Perng 90mm refractor with an SCT f6.3 reducer attached. Sadly I could not photograph a star field, but at least the Moon showed through the clouds and confirmed I could reach focus with 2 cm infocus to spare. Based on the photograph I took I calculate that the hackstrograph is operating at f3.76 and 338 mm focal length. Sadly the AZ-GTi still judders even in EQ mode, so I need to open it up tighten all the whatsits...

One concern I have is ensuring that the coordinate systems for the background stars and the asteroids (which have different data sources) are in alignment. I realized tonight I can simply generate charts for known historical occultations to verify this. I had hoped to verify directly with a little photography but it seems when it's not cloudy it's foggy.

I'd love to see Jupiter and Mars on a good night through a scope like that! I did see Mars through the 26.5" refractor in Johannesburg - 2000m altitude - but I was too young and inexperienced to fully appreciate it. I did see the canals!

I just haven't had the weather to get this one. I have an apartment block blocking view of it now