AstroKeith

1809 - Wonders of the Telescope Has lovely fold out illustrations ...

The dc to ac inverters are inherently less efficient, mainly I think because they are constrained to run at 50Hz. So as Craig says, plugging into the ac outlet on a power pack, and then using a dc power supply to get your 12V gives a double loss. But at least you get a stable output, but not for very long! Considering the complexity and value of our astronomy gear, we really shouldn't be running it off raw battery voltage. So you either find a power pack with a regulated output, or add a dc-dc converter (refer to my earlier link). dc-dc converters can be 95% efficient as they run at 20kHz typically which makes losses easier to manage. The problem with the 12V regulated outputs, is that they are 12V. Add a couple of metres of cable and the mount or camera etc will see around 11volts. Loads of threads on here and CN about problems this produces. The advantage of an external dc-dc converter like I linked to is that you can choose a 13.8V version. Just about perfect. BTW, all the built in capacity monitors, and the in-line sort you can buy are inaccurate especially when stepper motors are used in the mount. These monitors seriously underestimate the current being drawn as they dont sample the spikes.

It is clearly marketed as an astrophotography telescope - for which purposes no diagonal is needed or wanted.

I took a look at the Anker 521 specifications. I have a few Anker bits and they are all of good quality. I was surprised to see that the USB C PD output does not support 12V, only 5,9,15 & 20V. This immediately rules it out for me. They dont specify their inverter efficiency, but others have done some tests and indicate it to be perhaps 85%.

OK, the input to the converter goes to the cigarette lighter socket on the Anker. No matter what voltage the Anker puts out, the converter will supply a clean 13.8V on its output. Connect the converter output to your rig.

If you plug that adapter into the 3 pin mains socket on the Anker, you will lose capacity in the inverter. You are taking dc from the battery cells, the inverter is producing 240Va, and then your adapter is converting back down to 12Vdc. You are probably going to lose 50% capacity. Did you try that link I posted above https://www.amazon.co.uk/HOMELYLIFE-Automatic-10A-Waterproof-Transformer/dp/B07WFMG11F/ref=sr_1_1_sspa?crid=9Z5OFZ3C2DP8&dib=eyJ2IjoiMSJ9.PvkmenU9z0q22gENn7KTqYCTZfWVX3qMcmx1pz5LgsUCgwkZLBFM9-hMCdRCP0586xevs9Mg-WYnyccZtktdhC2unZvHwS3Hx5fI6GtE1qDj6cPEl65RiVhKvFxxlAO4ekpKdZjxKGp51YZ2JeH9tSqpP4v5AGnmqwVPFLfh4m7sKYosqfcY1t6Dnpp4TCt49e89GSuL_UtzsyoG6MhVg7w2pcbVhcwcGd3M-E8C5sBoE_4uN3_S8y-horE_VTg7bzotoyOphOpub1IcQVZMLJmFLGTTp4v6Yqjvg2PQE1o.X9NMHV6AeOWrZ2kl7WMQkd7k2slebkyW5jIZ2KpicqU&dib_tag=se&keywords=dc-dc+13.8+converter&nsdOptOutParam=true&qid=1727184799&sprefix=dc-dc+13.8+converter%2Caps%2C69&sr=8-1-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGY&psc=1 These are about 95% efficient.

Mounts that have stepper motors need to be well supplied. An ordinary meter won't tell the whole story. The stepper motors are driven by very short pulses, at many times what a meter will show the average current to be. Harmonic Strain drive mounts in particular draw higher pulse currents. These pulses can cause at least a volt drop down the cable, maybe two. The mount needs to be fed by a short stout cable directly from the battery/power source. Beware of non-brand power cables. About a year ago I bought a dozen various 1m cables from Am**on. With one exception they were rubbish. On dissection, two of them had just four 0.1mm stands of copper, yet they were sold as 6A cables. At 6A continuous load, initially they dropped 3 volts, but after a few minutes the copper gave out and they went open circuit.

Hold on! First it must be measured on load - the similar load you are using. It will immediately drop by about a volt. Then watch the discharge curve, at the load you are using. It will remain relatively high for most of the time, and then dive. How much useable voltage/time you get depends on the current being drawn. If you need a good voltage, then consider a dc-dc converter. supplier link this will give you that 13.8V constant until the battery output shuts down.

First split the dew heaters off - they dont need a regulated supply and can be swapped mid session anyway without losing alignment or data. The mount is power hungry, especially when slewing. Thick cables are a must otherwise you will lose 1 or 2 volts while slewing and goto. I'd look for batteries with regulated 12V output. Those with cigarette lighter sockets are unregulated and likely to dip under load. An alternative is to get a dc-dc converter from Amazon (9to30Vin 12Vout). As Elp says, get some measurements and then scale up for the number of hours you want.

Dont bother - it's a blank file. Nothing to cover I'm afraid.

Your bad file, isnt corrupted data - it's just blank. No header and the binary data is 'null' It's not a good rule to write to a USB stick straight off. The USB stick has firmware in it to manage storage and you may be getting conflicts.

In this case unregulated means it's straight off the battery cells, so it will vary as the battery drains. It will start perhaps at 13.5, stay around 12 ish for most of the time and then dive towards the end. The stated capacity may only be available to you if you can accept a voltage down to probably 10.5. The regulated USB C PD outlets will provide a constant 12V, even as the batteries drain down to 10.5. At which point they cut off.

I'm thinking that may be rather under-capacity for what you want to power. Have you added up the total drawn by your kit? The dreaded cigarette lighter socket will be an unregulated 12V. So you won't be able to get all the rated capacity out before at least on of your devices starts to complain about low voltage. If you do go with it, I suggest considering powering from the USB C PD sockets. Each of which will give you 12V 3A regulated.

Given that moment of inertia is proportional to distance squared, if you are trying to make tracking adjustments, I would bring the weights in toward the axis.

Is the nylock nut actually loosening, or is just that the bearings are settling in? These castings often are poorly machines and a bit of working in can help. But also try a new nylock, but before fitting make sure the thread on the axis is grease free.

Nice, do you have any photos or detail on the lower bearing?

I presume you have paid for the extra cabin bag allowance? The small bag has to go under the seat in front, and so is quite protected, but its so small! The larger bag has to go in the overhead locker, plus if busy they reserve the right to put in the hold. You cant argue with EasyJet when they make these decisions, even if they are wrong. You are standing at the gate with two options, do what they say, or dont fly. I used to fly a lot with gear, and used Peli cases. They are great, but heavy. Plus you still need a lot of foam inside. They are not suitable for cabin use at all. I assume you are going to the Atlas Mountains? I'd downsize to one rig and a pair of binoculars - the skies are amazing.

Hi, Can you tell a bit about the overall process, as I think we cant work out the need to remove the bright stars.

If you use a tool like astrometry.net, it will plate-solve all stars, and give you astrometric position data for all of them in brightness order. So you can manipulate the table to concentrate on the stars you are interested in. However, I'd look at the errors in plate-solving due to optical distortion (eg barrel distortion) which may only be partly compensated for in the solve. These errors will surely be much larger than proper motion? The astrometry.net people will advise on this - they are very helpful I have found.

I too suggest considering a Seestar50 if you are able to. I'm guessing you are in Ash near Whitchurch, which will be fairly free from light pollution as long as you are out of direct line of sight to a lamppost. I use a Seestar in Camberley which has quite bright skies yet it produces amazing images. Your 98% cloud is an exaggeration of course, but it does feel like it! Another advantage of the Seestar is that set up can be very quick, so if it does clear you can start observing. Its good for solar work too.

Good job (it did need a clean anyway!)

Oh dear. At least its not too big. First a very local attack on the poo. If its dried, then soften it first with fluid, but be very careful not to use too much such that it runs down the side of the lens. Use cotton buds in that local area to remove the poo once soft. Repeat many times to totally remove poo, then clean whole lens as usual.

Your biggest error sources likely to be tilt of the camera and lens assembly. You will need to mount the camera/lens into a 1 1/4" tube. and then rotate it to see if the centre of the image stays still, if not adjust somehow.

I would say definitely both sides, but mount the rollers so they can 'float' a little in the required direction (tangental to the track). The metal track should be fixed to the timber with slotted holes so if the timber warps the track can stay straight. Timber will change dimension only across the grain, so in general a building won't change size. It might warp, causing distortion, but bracing would help

I can get focus with a ASI120 mini. It is inside the eyepiece holder so only similar 1 1/4" cameras can work.