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Incredible image and associated effort! I'm seeing some sort of artifacts in red channel. Could these be due to mosaic stitching or is it something else there? It is strange however, since these are taken with OSC camera and any such artifacts would equally affect each channel - but they seem to be present in red only: here is a "blink" between red and green channel. There seems to be some sort of square / rectangular pattern feature in red channel. I first noticed it in this region in original image: where it shows as stair case of different hue.

I'm not much of a conspiracy theorist, but that is the only logical explanation for following: 1. No solid evidence (or almost any for that matter except "witness" accounts and dodgy aerial footage) 2. All statements are made in such way that they can't be either proved or disproved and can easily be later dismissed as "mistake" or hearsay in case anyone needs to be accountable 3. It is aimed at US crowd, there is oncoming elections in autumn (of next year?) there and perhaps some current administration blunders that are about to be exposed - need to be masked somehow? (I do admit that point number 3 is a wild guess on my part. I'm really not political analyst and I should probably refrain from any further comment in this direction to avoid breaking SGL rules)

That rather strange. I printed it on Ender 3v2 with 0.4mm nozzle and 0.12mm layer height. I managed to print down to 0.6mm pitch thread (that sort of works) with this setup so far.

Well, I obviously can't be 100% sure - but we need to look at two things: 1. Who is performing the show, and 2. Which theaters it's playing at

You do understand that it is a distraction technique? Let's talk aliens so that something that is actual and important slips under the radar of average Joe.

Hi and welcome to SGL. Skymax 127 is a decent scope and it will suit most of listed needs nicely (better for solar system, a bit less on deep sky objects), however, for your budget and stated requirements - I'd be tempted to recommend this: https://www.firstlightoptics.com/dobsonians/skywatcher-skyliner-200p-flextube-goto.html It is however very much down to other aspects like storage and transportation as well as managing the scope of that size. 8" dob is large and heavy, so you really need to take that into consideration. It will give you better views of planets and brighter views of deep sky objects.

But all the energy / matter still exists and hence relationship between their properties still exist (in one form or another) - much like money that might have changed from paper to coin or to electronic form - but nominal value remained or even changed based on inflation. I think that we have problem with world view above all else and as such, I'm not sure I can contribute anything further

Content? All the stuff inside it? There is no reason to think it is different spacetime and that previous stopped existing and now different one exists. Even if that is the case - we can still integrate numerical values as that is simple summation of things. You can calculate how much you earn in a month by summing up all the expenses and the money you are left with at the end of the month - even if you no longer have that money with you. In any case - distance is just comparison between two quantities of "stuff" that is inside space time. Stuff did not cease to exist nor was it created / replaced in the mean time.

Yes, and these properties can change - but that does not mean that spacetime vanishes or appears - it is the same spacetime just with different properties. One of these properties is distance - and we can integrate this distance as it changes over some other parameter - for example time

You will need to explain a bit more this statement. What do you mean by does not exist? It is the same space - but with "changed properties". Property of distance changed.

But it is. Along the path as photon is traversing any particular patch of space - it does so at certain time and due to expansion of universe - that patch of space being traversed is at different scale factor than the rest of the path. Ok, so here is simplest explanation that I can think of. Imagine following scenario. There is some example universe in which expands in particular way - say we have three epochs - early, middle and current epoch. Scale factor for each epoch is 1/3, 2/3 and 1. In each epoch photon travels with speed C which is some "epoch kilometers per second". Each epoch has its own "kilometers" which should not be mixed. We have early kilometers, middle kilometers and current kilometers. Think of these as different units of length, maybe that is better - like miles and kilometers - they measure the distance but have different numerical value for same length and there is a conversion factor (scale factor). Now, if we say that distance to edge of observable universe is 13.7Bly - what does that mean? Well that just means that if we had static universe and we shot the photon at C - it would take it 13.7 billion years to reach said distance. So we are using measure of distance that we know from present time - light year. It is "present" light year - one that we are familiar with (not early light years - from the past). Let's say that photon is traveling for 1/3 of the time in each epoch. How do we calculate in "present kilometers" how much it traveled? We will have: c_early * 1/3 + c_middle * 1/3 + c_present * 1/3 Where c_period has the same numerical value but is expressed in different kilometers - either early kilometers, middle kilometers or present kilometers. But we want answer in present kilometers to make sense to us, so what do we do? Well, it is easy - we have conversion factor, so we can convert it to modern kilometers by dividing with scale factor at given epoch. so it will be: c * sum ( 1 / early_scale + 1 / middle_scale + 1 / modern_scale) * delta_t (or 1/3 in our case) Do you see anything familiar in this formula?

I think I now see why we don't understand each other. There are two different sizes we can attribute to term size of the observable universe. One is based on light travel and other is based on "hypothetical ruler length" / or size in co-moving coordinates. equation addresses following question - thru how much (local) space did photon need to travel from CMB to reach us? That distance is not the same distance that we would get if we had hypothetical ruler that we placed at the same spot in universe and other end at our location - such ruler would give different answer. In each little segment of it's flight - photon had to "traverse" some universe. Universe between photon and us expanded, and universe between origin and photon expanded as well. However, in this case we are not interested in stretching between origin and photon - as photon already traversed that part and that stretching won't contribute to total length photon traversed to reach us. Only expansion between us and photon is considered. Now, we can simply look at above formula as much more common everyday scenario. You are in the car and you want to calculate the distance you traveled from the speed function. For constant speed we know that s = v * t (s being distance, v - velocity and t - time). However, if you have changing speed - you need to perform integral of v(t) * dt - or sum every little v*t for small t intervals where v can be considered constant. In above integral we almost have the same thing. With one difference - velocity is constant and can be brought in front of the integral - but scale factor - which represents change in length (and hence "speed" if we stick to definition of speed as length / time) is variable in time - so we must integrate it. If we observe following formula: which says that if we have some distance d0 now - at Hubble time t - that distance was smaller by factor of a(t). Now from perspective of photon - it traveled "full" distance, even if it was smaller at time t - so we need to do inverse - to divide with a(t) in order to get "true" distance photon traversed. That is why we have 1/a(t) in integral for light travel size of universe.

Integration is summation process. It represents the fact that at each "leg" of the journey photon expands by tiny little bit and all those tiny expansions add up to x1100 when it reaches us.

Hi and welcome to SGL. This is correct. This is also correct. Not sure how you came up with this part though. You should look at it this way: For every different spacetime segment there is a small change in scale factor which corresponds to small change in spatial length. Photon being in that segment of space time will have its wavelength altered due to this change in spatial length. Wavelength of photon is distance between two "crests" of EM wave - increase this distance (while photon is in this patch of space) and wavelength gets longer - photon is red shifted. Total wavelength red shift / increase in wavelength is sum of all small increases in wavelength that are consequence of scale factor changes and respective spatial length increases as photon travels thru each patch of spacetime

Quite right. Here is original post: That design is part of small telescope made out of binocular lens, so it has some features related to that telescope integrated. Above design is stand alone focuser and if you wish, I'll provide files for that as well.

I'm certain "it was", but I'm not sure two are comparable in speed. Speed of light is measured as distance over time. Cosmic inflation is measured (if I'm not mistaken) as scale factor over time.

or

I would not call that a research. That is simply a paper that will need quite a bit of evidence (research) to back back it up before it gets taken seriously.

How did you conclude this? Aberration is kept within this circle of 4 micro radians even at 22 degrees off axis If I'm not mistaken, 4 micro radians is equal to 4 * 10e-6 * 180 / PI = 0.00022918 ... degrees or 0.01375... arc minutes or 0.825 ... arc seconds. Humans can resolve about 1 minute of arc, so this aberration is about 60 / 0.825 = ~x73 smaller than we can normally resolve (20/20 vision) For comparison F/10 4" objective will have size of airy disk at 221.6" or 3.7 arc minutes - about x287 larger circle than presented in the image. It might be visible in some sort of afocal imaging method, but I'm doubting it will be seen visually by observer. As far as our vision go - this aberration is non existent. As for the eyepiece being glorified Plossl - have a look at spot diagram of a plossl eyepiece in F/10 beam (granted, we have no idea what F/ratio is above for TPL-12.5 - probably for ideal beam because it just shows EP aberrations not combined): So 10mm plossl at 0 degrees, 14.5 degrees and 20 degrees of axis - circle is e line airy disk for F/10 optics.

Not much, but I've seen that some variants of superglue are not very tolerant to heat. I had 3d printed case that housed banana pi single board computer that got really hot - like 60+ C for prolonged periods of time. Interestingly, pla that case was printed with - fared quite ok, but super glue that was used to put the case together started behaving strangely - I could find that whitish superglue residue all over the case - as if it had evaporated and condensed on other parts of the case. I did some research and appears that some CA variants don't tolerate heat (or rather you need high temperature one to resist heat above 80C). Maybe that can ease debonding? Another thing that is useful idea is to try it first with some scrap aluminum or unused bits (old extension rings) - apply super glue and then see what debonding method works the best?

Can you make a diagram of threads? I've found that extension rings and adapters have certain flex in them and depending on pressure that you put on them - you can either increase or decrease friction in threads. For example - with extension rings - you can unscrew one side if you use another extension ring that you screw in to the other side. Sounds funny - but it actually works. putting pressure on one side - on male thread for example with another extension ring (red arrows) will cause other side to expand outward (blue arrows) thus reducing friction on female thread. If your thin adapter is like this: meaning it has male threads on both sides, then, using force by pushing it towards the reducer will have negative effect: What you want to try is to attach another M48 extension tube and then "pull" on it as you unscrew the whole assembly - instead applying pressure towards the reducer (as you would instinctively).

Maybe even use ethernet-over-powerline adapters instead of running ethernet cable through the window? This is of course if house has power outlet on the outside. Mind you, I've found that circuit breaker board kills of the signal, so if you have several different "sub grids" in your house - make sure you use one where outside outlet is attached to (I have 3 different "zones" in my house - first floor, top floor and basement and can't bridge between them with powerline adapters).

Yes there is, but it really depends what you use to define "good" part. There is scientifically correct way to get visual representation of captured light. I'm sure that there is a good way to get visually pleasing result as well (probably not the same method though).

Nope. After meridian flip - only thing that happens is frame "flip" - or 180 degree rotation of the frame. Sometimes there is small deviation from this - like few degrees, and I'm not sure what is consensus on that one - if it's orthogonality issue or cone error, or maybe both.

And thanks to Dr. Sheldon Lee Cooper and Dr Amy Farrah Fowler Super-Asymmetry!