fifeskies

I cleaned my OOUK mirror without removing it from the cell. As long as you allow it to fully dry before powering up the fan again it will be fine. Distilled water and cotton wool balls is the way to do it. Only needs cleaned if there is a lot of dust on it though , a small amount will not matter a lot. My mirror had several years of dust build up so did benefit from cleaning. Pour the water over the mirror first to wash off any loose dust, then just be very gentle and wipe from centre to edge using each cotton ball just once,

That's the big group off round the edge now, not much other sunspot activity just now. Image gives a nice view of the "Limb Darkening" effect , where the edge seems a lot less bright than the main disk.

Turned out to be a display screen problem

I use win10 pro and "remote desktop" to run my dome. There is a PC inside the dome connected up to all the various bits via USB. From there a single Cat6 cable travels the 25m to the desk beside my cosy woodstove where I have my other PC set up. Never had any problems logging onto the dome and watching the magic happen.

I think the 2GB limit is actually the 32 bit Microsoft Windows limit on file size. I use Registax 6 on a 64 bit Windows computer and process full disk solar captures of around 50Gb. Also make sure you have the latest version of Registax 6 as file handling for large AVI has been tweaked in latest versions. (Note: this will take forever unless you have a fast PC with lots of RAM and a very fast SSD storage drive , I have 32GB of RAM, an NVMe SSD capable of 6Gb/sec read/write and a multicore processor at 3.9 GHz, and it still takes some time to complete)

Astronomy Threads Explained (agenaastro.com) Hope this helps

While that will work it gives no control over the heating straps , ie full on all the time. You generally need to reduce from full output, mine run around 20% to 40%. Only higher if very heavy dew on a cold night. There are several options for in-line control that sit between the PSU and the heating strap itself.

interesting to compare rotation from yesterday

Among other ways to seal these other than grease are :- adhesive lined heatshrink (But this makes for a very rigid connection) Or self amalgamating tape (This forms a flexible rubber like sealed cover, but remains slightly sticky for a while)

I should have added, I use a big 13.8v linear supply, so can easily cope with a voltage drop of a volt or so out to the mount. If your supply only delivers a flat 12v , as CraigT82 has mentioned above you may need to use heavier gauge cable. Most of the re-wirable adapters can be persuaded to take up to 2.5mm stranded cable, but check the exact ones you are considering , they vary in quality. Crimped termination sleeves to the cable ends can help to fit them into the adapters.

rewirable adapters allow you to easily make up any length of high current DC cable without having to solder large cables onto small fiddly tabs. I use 1mm 2-core rubber cable (or 2-core 0.75mm for shorter runs) It can be a good idea to also use an inline fuse.

Rule of thumb is that focus will change by 1/3 the thickness of the filter , so a typical 3mm filter will add 1mm. It is because the refractive index of glass is not the same as just air. To focus with Ha filter and Bahtinov , just push camera to high ISO , just remember to lower it again before imaging.

False colour image derived from Green continuum filter.

Derived from narrowband continuum filter and Baader Coolceramic Herschel, Vixen SD103s Zoom in for full view False colour conversion from Green original.

The tripod handset cradle for Synscan (or similar) handsets is not that suitable for fixing to a pier. (and a suitable spare is relatively expensive) I came up with a very quick and easy way to make a cradle that can either be screwed to something or hung from a hook with some nylon cord. I used some 4 inch PVC gutter offcut and a heat gun, heat the edge and use a flat piece of wood to press the soft edge against to mould the shape you need.

When I first visited Tenerife there was almost no-one visiting the crater at night so the dark skies were undisturbed. These days there seems to be a regular set of tourist minibus groups that visit the crater every clear night with their powerful laser pointers cutting up the sky. Its not just confined to one part of the caldera as the minibus convoy seems to split off to all the best spots with ample parking. However if you wait it out they are pretty much all gone by midnight.

Anyone else noticed the error in this year's giveaway calender 30 days hath . ........ (And no it's not on the June page)

+1 for using the UV-IR filter on guidecam Have one on my ZWO290mm mini and it gave much tighter stars when observed in the PHD2 monitor window than it showed before the filter was added.

Since 8 x 1.2 volts is only 9.6 this makes rechargeable batteries replacing a 12v supply slightly tricky. One solution is the easily obtained 10x battery boxes designed to overcome this , using a flying 12v lead to plug into the mount 10 x 1.2 volts is of course 12v , just don't mix in any normal batteries with the rechargeable ones.

Is that a 1.25 wedge on the ST120. Looks like it has used up most of the in-focus so I doubt that the longer path needed by the 2inch Coolceramic will allow it to obtain focus in an ST120 , unless anyone knows for sure that it does. Nice little solar setup all the same Just a note , I would remove the Telrad when looking at the sun , you can melt the target screen if the sun is high and strong and you accidently pass the strong sun across the top when aligning the mount , the little lens inside it can focus back into the Telrad

I am using my 2 inch Baader Herschel with my William Optics Zenithstar 61. There is not enough infocus to use my DSLR with just the 2inch snout adapter so I have taken some photos with my phone. Very pleased with how well the wedge performs. I am however thinking of upgrading the scope I use, a bit more aperture and hopefully with a better infocus range, (I only need around another 20mm at most). What are others using with the Baader wedge. 2

10inch f6.3, Orion Optics UK

To answer this we need to know what camera it will be going on. It may be your camera already has a filter (eg if you are using a DSLR). Most ZWO cameras do not have any filter out of the box , just an anti reflection glass window (AR glass). In this case a IR/UV can be an advantage depending on the target.