wimvb

Agree, better to get the clean Ha and Oiii masters to work on.

If you put Polaris in the small circle on the polar scope reticule, it will move over time, because Polaris is not at the true Pole. There are aids such as the Synscan app, which will tell you were to put Polaris in the polar scope eyepiece.

Difficult to come up with a good answer without further details. Is your mount on a pier or a tripod? How did you polar align, and how did you then check it? How far off is it?

The skyguider, afaIk, only has one motor, whereas the heq5 has two. Have you updated the asiair settings? I use indi and ekos, but for every item I change I have to update the profile. My guess is you need to do something similar.

Location isn ’t going to be much of a problem; I live well away from any neighbours, my house is on a ridge, and the few high trees around are mine, and planned to go down in the not so distant future. But the anemometer will definitely not be placed on a 10 m high mast. Just above the obsy will do for me.

The cheap chinese anemometers, such as the one I have, come in a variety of flavours, from modbus to pulse to analog output. If I can’t get mine to work, I’ll have a look at the electronics inside. What appealed to me when I bought it, was that the rs485 version was already calibrated.

It's not a full station yet. I have a rain sensor which I haven't implemented yet, and am struggling with an anemometer. Most of the sensors are very basic. They all use i2c, which is easy to implement. The rain sensor is analog, also easy. The anemometer uses rs485/modbus, which is a completely new protocol for me. Information on the internet suggests that it's straightforward, but not so. I can read values from the anemometer with a windows modbus master. I can also communicate with arduino code and a modbus slave emulator on windows. So I know the various parts are working as they should. But I can't get the anemometer to talk to the arduino or esp32. I've tried everything, including various ttl-rs485 interface boards and chips, but no success. I will try connecting it to a rpi with the usb/rs485 adapter, but if I can't get that to work, I'm considering hacking the anemometer and use its analog signal, bypassing the modbus logic alltogether. This is my hardware https://www.amazon.co.uk/gp/product/B07WD8LZD6/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1 https://www.amazon.co.uk/gp/product/B078X5H8H7/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1 https://www.amazon.co.uk/dp/B0721BB8PQ/ref=dp_cerb_1 Max485 chip https://www.amazon.co.uk/gp/product/B07G1867ZX/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1

For cmos: removal of any amp glow. Otherwise removal of outlier pixels. The same way that you can evaluate a master flat by doing flat calibration of a single flat frame, you can evaluate a master dark by doing dark calibration of a single dark frame.

If the Nii source is bright enough, this may work. But the 5 nm filter will also contain red background, more than the 3 nm filter. So, it depends how much each filter will let through outside the Ha and Nii peak as well as outside its passband. Plus you will have to consider the transmissivity at peak for both filters. All in all a non trivial exercise in mathematics.

That shouldn't increase std dev much. Calibration should. What camera do you have? Darks don't always work with dslrs for example. But since you've matched temperature, I assume you have a cooled astrocam. Btw, if it's a cmos, make sure you don't scale the master dark.

The first image is "after". If the dark is noisy, there may be a substantial increase in std dev The square of the std dev after equals the sum of the squares of the std dev of the uncalibrated image and the dark (if the noise is truly random) S_cal^2 = S_uncal^2 + S_dark^2 That's why it's important to take many darks.

Very nice indeed. As you already figured out, more data would improve the image, and make processing easier.

So does @Ken82, but we still haven't figured out whether it's metric or imperial. But it is a real hoot. Btw, the 17th century warship Wasa (which sunk on her maiden voyage, never making it out of Stockholm harbour) was asymmetric. Inside the ship 2 types of measure sticks were found, each a foot long, but one had 12 inches to the foot (English foot), the other 11 inches to the foot (Amsterdam foot). Maybe this whole metric vs imperial thing the real reason why Elon Musk/SpeceX only hires Americans. Or not.

Surface mounted? 😁 for strip board, there is veecad. Good enough for simple, one of projects and quick prototyping. Not so good for valves or smc. https://veecad.com

The left image for me. Viewed on my iPhone, the right image seems to have holes where there should be stars. Maybe replace the stars at original strength after you’ve strengthened the nebula?

My first guess is that it's the post processing that needs addressing. Which ever software you use, colour calibration should be your first order of business. In PixInsight you'd use background neutralization and colour calibration for that.

As @sharkmelley already hinted at: you also need to look at the noise, fwhm is only half the story.

You can have that stone that broke my knee cap last winter, for free. 😁

Does it fit the AZ-EQ6 GT?

According to wikipedia: "The stone or stone weight (abbreviation: st.)[1] is an English and imperial unit of mass now equal to 6.35 kg (14 pounds).[nb 1] England and other Germanic-speaking countries of northern Europe formerly used various standardised "stones" for trade, with their values ranging from about 5 to 40 local pounds (roughly 3 to 15 kg) depending on the location and objects weighed. "

Limestone, I'm not taking anything for granite. (That was all too easy)

And how many stone is the load capacity of your mount?

So what have we learnt from this? That manufacturers can cut a losmandy plate any which way they like and it will be exactly 42 units long.

So do plumbers

Me 24/12 😉