AstroKeith

It's a rather nice nod to the grand refractors (and a few other scopes) of yesteryear. Take a look at the back of the 36" Yerkes telescope - lots of brass, wheels and the same steering handle.

Are you sure it's red? I've only ever seen green Zygo tests. The report should also give strehl, rms and astigmatism figures.

The choice does depend on the scope focal length of course. With my 18" f4.5 dob it used to be the 17mm Nagler that hit the sweet spot. This was replaced by the 13mm Ethos. Same field of view but more magnification hence darker background and better performance on the faint fuzzies. I use the 13mm 80% of the time. It got my vote in your poll. Recently, with my plate solving finder, I find I use the 10mm more. Not having to search for the object has made a small difference. I used to have a 6mm, but didnt use it enough so that funded the 10mm. Now I have the 8,10,13,21 and a x2 power mate.

Thats good new. Typical of Serge's excellent support, despite the fact it is he dealing with someone else's product that is made with poor control of tolerances.

Just watched Ed Ting's review. I think he is right on so much - in particular it's not great image quality and much better is coming. But, I believe his conclusions are biassed. I'm a visual only observer. I go after really difficult objects and work actively to improve my own visual performance. Never gone to the 'dark side' (what I call astrophotography), since why not just look at images on the web! But I've bought one. Costs less than an eyepiece (my Ethos at least), or a week away at a star party. I'm enjoying the technology. It's a good package and must not be compared with astro-photography rigs costing £1000's. No doubt we will see firmware upgrades (post processing and mosaics). Meanwhile I'm having fun and it's something I can share with my grandchildren without them getting bored, cold and disillusioned. Heh they might even get interested in astronomy! I design telescopes and tracking systems, and ZWO have hit a good spot. Almost everything Ed wanted could double the price. Except better processing which is almost free. Even a bigger sensor might sound affordable, but it will impact the optical design (size of flat field) filter apertures, etc and prices will spiral upwards quickly. Next time I'm out with my 18" Dobsonian, there will be little friend nearby on the ground busy imaging. (Albeit with gaffer tape over the LEDs!)

Not so. A cold surface (your dome) will attract condensation if it is colder than the dew point of the air inside. Warm humid air (ie air from outside) will have a high dew point and be likely to condense. To stop this you would have to blow enough air through to dry off the surface - a lot. Its quite simple, you are getting condensation, therefore the air inside is not dry, therefore your desiccant isnt working in this instance

If you open it now, what colour is the silica gel? It clearly isnt working as a desiccant, or it is saturated. already - Laws of physics.

Well, the air in the box is saturated with water. That for sure. So either, The desiccants are saturated and/or not enough (a 50 gem pack is about minimum. It isnt sealed. Carbon Brush gave good advice, I wouldn't cook my gel at 100C though. I find 60 for 2 hours enough.

That is why the sealed version has desiccant. It reduces the RH of the internal air to about 10-20% which reduces the dew point to a figure that cant be reached. ( I used to design optical equipment for the services) Rain is never truly vertical and anyway will run down the sides of the box. So your vents, grills and foam will be damp at best, soggy at worst. The Starlight Xpress Oculus all-sky camera uses holes underneath I believe.

If it truly sealed, and has desiccant, plus a dew heater, it cannot mist up. All three are required (sealed, desiccant, heater) Or as I said, the ventilation holes must be underneath, no fan, reasonable high power to the dew heater.

There are many different approaches! First how much power are you putting into the dew heater? The holes in the sides, are they protected from rain and dew? It would be more usual to have them in the bottom. If it's an open box, I'd suggest not having the fan on, and the heater on max power. Otherwise the heater is going to fight a losing battle with fresh damp air coming. You want the heat from the dew heater and Pi to build up inside the dome. My own version is sealed. It has a dew heater and silica gel packets which I change every 3 months or so.

Amalthea was easy at the Texas Star Party in 16" & 24" scopes, but we had to wash the dust off first. I've seen it once from Kelling Heath (UK) in my 18", again very clean mirrors.

Two 'clear' half nights out of 7, but still had a great time. Great to see so many there. Good to see Widescreen and Altair Astro on the Saturday. Kelling did a fantastic offer on the food. Monday night's curry was awesome.

Monday is load up day. I'll be taking my usual 18" Dob.

Definitely not the first, and not quite the second! EQ platforms are the 'flat types' used under Dobsonians, but not goto's - they dont need one. EQ platforms are used with push-to dobsonians that dont have any drive at all. They provide about an hour of tracking before they need 'winding back' to start again.

My own view, is that the 'popular' Dobsonians have been cost engineered down too far. The mirrors are generally of good quality, but the mounts let them down. The non-Goto/tracking variants suffer from poor motion and altitude balance issues. The GoTo versions have drives that are borderline adequate, and often fail to perform. I've seen very few budget Dobsonians that can hold good collimation for a whole night. The solid tube versions are best, but again the mirror supports and focusers are 'basic'. I even had to rebuke a popular vendor who tried to justify poor mounts by saying it was the optics that are important. What good are optics if you cant get a stable image. The step up to a 'premium' Dobsonian comes with a significant increase in price and weight. A good solid basic Dobsonian on an EQ platform can be a good solution for some.

Great videos! Clearly shows the problem. Are both axes affected? Are the inserts supplied the same for both axes, I believe they should be different.

The female metal part has to grip the white disk strong enough such that it doesnt rotate when the screw is rotated.

Is the metal female part slipping in the white disc? When you continue to tighten - can you tell what is slipping?

Nicola, did you see someone has just posted some Ethos for sale!

Just to be clear - your list Kstars... etc, is that on Ubuntu or Bookworm? I've used the second display port a lot, but never the audio. I guess they removed it to get some board space? I have one with a 512gb NVMe drive connected to the PCIe bus which runs nicely.

OK, try this Before inserting the assembly in your top photo into the mount, wind the screw in so the white 'cone' is just starting to grip the inside of the black part. Insert into housing and try tightening the screw. If it still dosent tighten, then remove and wind the screw in to give more grip. Try again.

The relatively new Pi5 is now readily available. It gives a massive improvement in speed - at least x3 on most tasks, sometimes more. I'm blind plate-solving in about 0.6 seconds. I have modified my own kit to move from the Pi4b to Pi5, and it wasnt a complete drop in (not just the USB socket arrangement reverting back to the Pi3 layout) The biggest issue is the new Debian 12 Bookworm OS. This has made some significant changes to UART addressing and GPIO pin handling. Plus a much more formal approach to users, with virtual environments being almost essential now (Good Linux practice anyway) I thought it might be useful to collate a list of what works and what doesnt. Please comment if you have any experiences, good or bad with the Pi5. As a starter, this is what does work: astrometry.net Skyfield Astropy ZWOASI camera SDK Phidget module support What doesnt work: Netatalk (but Samba is a good alternative)

What telescope and kit type do you have?

Relatively easy to replace. Here's an example - you might need to hunt around if the pin placing doesnt look the same, although usually they are standard. https://www.amazon.co.uk/sourcingmap-Double-Female-Socket-Connector/dp/B00NQ9TN6E/ref=sr_1_15?crid=2HHOOZLKDS8BU&dib=eyJ2IjoiMSJ9.h8G5XSk3XvVsmG51CfWYC2Nho_v7F2yGuQcgaccLuQpqhOTXj_7fbauPh490VGlCMCRsw1RY5LNbGJAeq0UTOtr4nE-T7sJCOEyFX3rCcxpMfpImzjTIwvWNzj_m_XFHHbuf7tyfavCXQDCGhJfShMALi7o4X-P8C5ngT0IhAIhGZ6C70tqP7_7_tda4RYEkN6CskREoG5yuqk128xMMP5_ZkiEASr1kgCE7cxfIRqs.XVxtTKIKjJ0-Zitdv0SrOBFzMdfWFn9gPC5Ol9t7g34&dib_tag=se&keywords=usb+pcb+socket&qid=1708538964&sprefix=usb+pcb+socket%2Caps%2C172&sr=8-15