Seelive

I wonder why it hasn't fully removed the stars over the galaxies?

Have a look in your PC instruction manual, it should tell you the recommended operational and storage environments. Any decent make should be capable of operating in ambient temperatures between 0 and 35°C (32 and 95°F) and have a storage (non-operating) termerature range much wider.

I'd go for a prime lens rather than a zoom. My first ventures into astrophotography were with the Canon 50mm f1.8, even today it is just over £100 new and £60 - £80 second hand. With your Canon 500D and a 50mm lens you will just fit in Orion with Betelgeuse and Rigel in opposite corners but will still be able to make out the horse head and flame nebula easily. With your EQ5 you should easily be able to go up to 200mm without any guiding but the longer focal lengths will come at an increased cost.

Try here: https://stargazerslounge.com/topic/247247-mesu-200-ra-guide-speed-correction/

The flats for my Canon 200d are usually around 1/1000s (0.001s). I guess it could depend upon your light source and whether it has a particular refresh rate that may cause a problem.

The RA and Dec of mounts normally have different gear ratios, generally the RA will have a higher gear ratio than the Dec as the RA is usually the most important to be most accurate (see here for examples https://www.astroeq.co.uk/tutorials.php?link=ratios#eq3-2_alternate) So, if you plug the RA motor drive into the Dec motor, it will probably seem to move faster and visa-versa?

Here are a few photos of a fork mount I made for my 10" f6 Newtonian back in the mid 80's that may give you a few ideas? The fork was constructed from welded 3/4" square 16 SWG steel tube covered in 16 SWG steel sheet (I didn't have the facilities to weld aluminium at home otherwise I would have used that instead). The fork was supported on 14" diameter cast iron wheel (a concrete mixer wheel I found at a scrap metal yard) running on 2 rollers and a 2 1/2" steel shaft into a thrust bearing. The base was made from 6" x 3" x 3/8" steel angle, 4" x 2" x 1/4" steel 'U' channel and a 3/4" thick steel plate (all picked up from scrap metal yards). All the metalwork was 'machined' using a hacksaw and hand file but all lathe work was done at a weekly model engineering evening class at the local college. It did have the hand written plans but they went with the mount when I gave it away on UKABS. This is the mount and scope at its prime inside my observatory circa 1985: This the RA wheel and rollers (taken when I was dismantling the mount circa 2010 prior to demolition of the observatory - everything has suffered from several years of being unused and a leaking observatory roof!) And finally the RA shaft and thrust bearing (the white disk is the 12" diameter 360 tooth RA drive gear, also made together with an identical declination gear at the local college).

Is it the thread on the bolt or the thread on the mount that's stripped?

My query was referenced to what is the source of Vpp+ on pin 6 of the multi purpose port (on all versions?). My assumption is that it originates from the hand controller, independent upon the hand controller version, and I also assume it will be 12V when the handset is connected to the mount (or external PSU for the V3 version)? Edit: Having re-read my instruction manual, pin 6 on the multi-purpose port is a power output (with a voltage equal to 0.7V less than the power supply voltage (12V?) at 100mA max) so I've answered my own question.

As a guess, I would expect that the 12V on the SW RJ11 plug is actually supplied by the handset as I'm not aware of any 12V supply being available from the standard RS232 9 pin D interface. The Servo Driver interface appears to be intended to directly connect to a standard PC RS232 interface that would use the +/- 12V levels so I would expect the USB to serial converter to output true RS232 levels rather than TTL levels (certainly what my FTDI CHIPI-X10 USB to RS232 converter does).

If it helps, you can find the Mega Fabs D1 Servo Driver datasheet here https://www.google.co.uk/url?sa=t&source=web&rct=j&url=https://www.hiwin.us/wp-content/uploads/d1_drive_user_manual.pdf&ved=2ahUKEwi7j7zT0u_zAhVwQkEAHV4nDXEQFnoECAgQAQ&usg=AOvVaw3HtitA10MWa2Un4qlj4zj5 and compare its RJ11 signal connections (page 36) with the SkyWatcher RJ11 signal connections shown here https://www.google.co.uk/url?sa=t&source=web&rct=j&url=https://inter-static.skywatcher.com/downloads/Synscan_V4_Hand_Control_Manual_SSHCV4-F-161208V1-EN.pdf&ved=2ahUKEwjKq8TD2e_zAhVjnFwKHbUlCHoQFnoECAUQAQ&usg=AOvVaw3JjXThEGFPoTDdouJALv6s (page 48).

Does your controller currently do what you want it to do? If so, why bother updating the firmware? If your handcontoller isn't the version with a USB type B connector (in which case you'll just need a standard USB-A to USB-B cable) then it should have come with a RS232 to RJ12 cable, so you would just need an USB to RS232 converter (get an FTDI one). Unless you are sure that RJ12 connector signals exactly match those of the handcontroller then you risk causing damage.

Hypersensitived Kodak Technical Pan seemed to be the in-vogue emulsion when I used film but I never had the facilities to hypersensitive it so Tri-X or HP4 with push processing or one of the 'new' 1600 ASA colour slide emulsions together with manual off-axis guiding for what seemed like forever! (Well at least 10 minutes). Oh, it's so easy these days 😆.

That explains it! Hope you go on to get great results using your filter.

If your local light pollution is predominately LED lighting is it possibly transmitting the peak of the typical white LED spectrum at about 470nm which is at the blue end of the spectrum (and possibly within the Skytec CLS passbands)? Do you see any stars? What do you see if you point at a 'bright white-light object' (eg the moon or a daytime landscape object), is the colour tint blueish?

According to my EQM35 instruction manual (Part X, page 34), to update the firmware you just need a standard USB type B cable which plugs into the USB socket on the handset and the USB socket on a PC. The online firmware update instructions do not appear to have been updated for the latest handsets that now have a USB port rather than a serial port. (I've had the mount for 2 years now and the firmware has been updated since I purchased it, but as it does everything without a problem, I've never felt the need to update it.)

Yes you can but for large targets (in relation to the FOV) the position of the target within the images needs to be very close between sessions otherwise you'll just end up with an even smaller usable FOV.

I assume it's a low pressure sodium lamp which are easily 'suppressed' by any of the standard light pollution filters although if you are only troubled by LP sodium lamps they will also unnecessarily take out a lot of the other spectrum. Many years ago (when all street lighting was LP sodium) I used a filter that just removed the twin D lines but I'm not sure if you can get anything that simple the days! But I wonder if a single lamp will cause that much of a problem? I have a roadside LED lamp 10m away that illuminates my garden but it's the light pollution from the local town and large industrial estate that causes the light pollution. I've tried LP filters in the past and just don't like trying to deal with the resulting colour balance. Nowadays I just take more subs so that I have the chance of extracting the faint detail from the background noise caused by the light pollution (OK, the image dynamic range is reduced but I can cope with saturated stars as long as I can get the fuzzy stuff).

That's when the data sheet for the battery is invaluable (which should be available for any branded battery).

If you believe my Ladybird book on batteries, definitely not - the higher discharge rate will likely hit the battery harder.

I have my mount permanently fixed to its tripod and have 2 East-West marks in my garden where the tripod legs are positioned each time. As my garden slopes quite considerably I then use a spirit level on the mount eyepiece storage plate to level the mount. Actually, it isn't truely level (it doesn't need to be) but it just means that every time I set up, Polaris will be well within the Polar Scope field of view (so I don't need to hunt for it). I always polar align before I can see Polaris with the naked eye - I've always found I can see Polaris through the Polar Scope before I can see it visually - and it takes no time to align Polaris to the correct place on the graticule.

You can easily check whether it's the polar alignment or periodic error that's the likely cause of the trailing by taking a series of short exposures (say 10 to 30 sec) over a length of time equal to several rotations of the worm wheel (so for the the Star Adventurer a multiple of 8 minutes) then stack the resulting images WITHOUT applying any alignment. Any polar alignment error will show as a slow but constant drift in a particular direction, periodic error will show as an oscillation either side of that drift. The following image was taken with my old home-made tracking mount (starting on the left) with no period error correction applied and then midway though the series of exposures periodic error correction was applied to the motor drive (a magnified view of an image taken using a 100mm lens and a camera with 3.7um pixels): Since the periodic error effectively describes a sinusoidal waveform, if you happen to expose during either of the two 'zero crossing' points of the sinusoid the trailing will be significantly greater than if you happen to expose during either of the peaks of the sinusoid. Since the worm rotation of the Star Adventurer is 8 minutes, depending upon the imaging focal length and pixel size you could possibly get away with a 30 sec exposure at the crests with negligible visible trailing but the same exposure at the zero crossings would show some trailing?

If I'm correct, the Star Adventurer tracks in RA only so if you intend to use your lens at 600mm you will need to have VERY precise polar alignment to achieve any reasonsble length exposures. I use a 400mm lens with an EQM-35 mount (which is basically a Star Adventurer with a declination axis and GOTO) but still need to use a guide scope in order to achieve my typical exposure of 180 sec at F5.6 and ISO1600 without having to discard any images.

That makes sence, thanks.

Excuse my ignorance but wouldn't selecting the 'Super Pixel' bayer transformation result in a monochrome image from a colour camera?