ONIKKINEN

Have you ordered all of that already? Might want to rethink that corrector as it does not correct coma completely and has generally terrible sharpness across even a small field (see spot diagrams and reported RMS radius). Nowhere near diffraction limited, i am pretty sure your current refractor has better sharpness than the Maxfield would give. I had one, but then again my scope is a little bit faster than f/5 so in a worse starting position so might not be that bad for yours. But overall would never recommend that to anyone just because of the absolutely butchered spot diagrams it is designed to give. You can borrow mine to test if you want to, was not planning on ever using it again anyway.

I meant resize as in resample or bin, which is a typical action when processing. Cropping would not matter for arcsec/pixel calculations.

Image solver works with stretched images, jpegs, PNGs, you name it. If the image has stars, it can be solved. Most likely some setting issue then. Is your pixel size, focal length and coordinates input correctly? Remember that if you have resized the image during processing the "pixel size" is no longer the same as the ones found in your camera and you have to tweak that parameter accordingly.

Just a dew shield + i ordered my tube to be a little bit longer than it should for the focal length. The secondary sits maybe around 40cm recessed into the tube. But also, the spider in mine has a 60mm central diameter while the mirror is only 63mm in minor axis diameter so very little pokes out from behind it. So far have only found ice on the edge of the secondary once, but to be fair i only happened to check out of curiosity that time and not because i noticed something was wrong. Could be happening more often but if it is its not a major issue. If you plan on mostly imaging with the planet scope then you should go for the biggest aperture you can muster. The small maksutovs are good for their size and price and apparently for visual because of their great contrast, but will probably lose to any decent 8'' newtonian when imaging. Actually you could go for a 10'' even, if you plan on only taking on the Moon and planets since tracking accuracy is not that critical for that use. Wind is a real issue though, no solution for that. Have made a round trip to the Porkkalanniemi site a couple of times without even bothering to set up because it was too windy. Some other times i chose a mosaic target that i could bin x3 or more so that i can "hide" the bad data caused by wind. But in that case you could just skip the headache and use the 90mm that probably doesn't fall apart in a breeze.

Just had a look at the FITS file, stars look very weak and soft with only 39 found with the findstar command. Looks like the shots are well out of focus and i think DSS wont be made to stack these. I think you might get an image out of Siril with subs like these as long as the rest are not too much worse.

Try with another stacker, like Siril? DSS is quite picky about what it considers a star and what it does not. If the shots are underexposed and/or trailed/out of focus then DSS might not want to use any of the images.

My scope is basically the TS f/4.5 ONTC at this point, but it came to be so as a ship of theseus and not a single purchase. The initial scope (VX8) was around 900€, carbon tube from klaus helmerichs 380€, better secondary spider 200€, Baader diamond steeltrack focuser 400€, CNC rings and losmandy plate maybe 300€, flocking and other miscellaneous stuff lets say 100€ (at least). At this point the price starts to look the same as the TS ONTC version, so i think their price for that scope is quite fair.

The safe bet with that budget would be an EQ6 or an AZ-EQ6. The difference between the two mostly being in how you polar align and some other convenience changes (slightly more modern design in the AZ-EQ6). These mounts are dead simple and have been proven to work so it will be a safe bet, which may not be the case for the new harmonics.

Mine has a roughly 33% obstruction, and its definitely not too much for imaging. For visual, it has been an issue for a few times although it has been a while since i actually looked through the scope. The central obstruction can be visible at lower powers and in a bright environment such as very light polluted skies or looking at the Moon. By the way even if you do have a small sensor now, will that be the case in the future? Sizing the secondary upwards might be a smart choice that saves you the headache of refitting one in the future. Also it will help with flats somewhat. Its very easy to have an off-center fully illuminated circle with a newtonian and with a small mirror that will have a greater effect on vignetting and may become an issue.

Yes, thats the gist of it. It really is that simple.

1,2, sounds good. 3) Yes, sounds about right. You can slew to vega from the manual focus stars list (or externally from stellarium but i dont recommend it, its just an extra step with little benefit). Once the slew is complete you will likely see that Vega is not in the frame. Hop on to the platesolve tab and run it with re-slew and sync options turned on and then it will take an image, platesolve, re-slew, rinse and repeat untill within tolerance. Word of warning here, some mounts dont like the sync option and you can leave it off if you notice something weird.

There are no added complications, and in fact most of the complications, including "normal" alignment go away. The first slew will be off but it doesnt matter. An image is taken after the mount communicates to NINA that the slew is complete and then it platesolves. If the mount is no more than a few degrees off, which is usually the case, then the platesolve succeeds in a second or so. The mount is aware of the coordinates it think it is pointing at, and this is the basis for the platesolver where reference stars are searched in a spiral fashion around the reported area. If the mount to sky error is large the search time can be longer. But that will not happen unless there is loss of power or manual movement of the axis (such as bumping the mount). Astap can platesolve locally with files on disk, and can even blind solve (no mount communicated coordinates, such as with a simple non go-to tracking mount).

Have you set up Astap platesolving yet? Once that is done you can auto center targets and can forget about stellarium and star alignments.

The price is not so shocking to me, considering that there is an apple buffer of at least 1k and that the tech here seems to be pretty good. The display seems to be decent with "23 million pixels" (no other information in the link) overall. Probably something close to a 3000x4000 pixel display for each eye or something like that. I have a Valve Index but to be honest it sees little use because the resolution is just not there. Reading text or trying to see fine detail on anything is a chore for the eyes with the 1900x1440px displays in the index so its still deep in the gimmick territory IMO. Problem with better displays is that better hardware is needed to push those frames, and framerates will need to be high or the illusion of VR really falls flat which is a double whammy: large resolution and high framerates which means no GPU on earth is capable of doing the job yet. I still think we are a good 5-10 years from resolution and GPU power being at a sweet spot, although i might have said the same 5 years ago. But still, universe sandbox and No mans sky are really fun in VR even with the limitations. Would love to see more astronomy related apps for sure.

Discussion of dark frame optics tends to end in a locked thread so lets not get into too much detail, but the short version of the story is dont bother with that company. You could search the forum for that topic, although im not sure any threads have survived. 11kg will absoluyely not happen on that mount, its just too flimsy structurally. I have an AZ-EQ6 and would consider 11kg a high payload! I used my eqm35 with a VX8, which initially with a DSLR weighed around 7-8kg which was already too much. The mount will simply not guide well under such loads and i ended up turning dec guiding off and only shooting at high declination targets with short exposures to get away with no dec input. If you have a heavy setup on the mount i highly recommend you reconsider the choice of mount before you go bald from the stress of dealing with it.

You dont need to change anything in the EQMOD settings, it will work even though it says its for an HEQ5. Sorry to tell you but there isn't much to hypertune in the EQM35 since the innards lack bearings. Its all supported by plastic washers and lubricant so any weight you put on the mount will immediately strain it. In my opinion its not a mount suitable for setups heavier than 5kg, and in an ideal scenario it would not be used for astrophotography at all. That said, the factory finish is quite crude, with either too much or too little or the wrong type of lubricant in the mount so it will benefit from a teardown and clean if only by little. I found my EQM35 a little bit less bad after doing that with balancing seeing a noticeable improvement.

You conveniently ignored the entire point of my post. You can get the exact same wide field of view with the C11 with mosaics, and still be faster! There is no world in which a smaller scope gathers more photons than a larger one. Best of luck with your imaging, i wont bother commenting on your threads anymore.

How is it possible that one scope takes bad data in poor seeing and one scope good data? Its not, if both datasets are treated equally at the same scale. You are comparing the C11 at its native scale to the TOA130 at its native scale, a comparison that has the goalposts moved so far that the argument in my opinion falls flat immediately. The "lost to wind" argument also doesn't make a whole lot of sense to me. Are you saying that binned x3 a large portion of the subs are still so far beyond salvation that they have to be scrapped entirely? Again, if you bin/resample both the C11 and TOA130 images to the same size, the C11 will win every single time because it has more than 4x the aperture area. Clinging on to the argument that you dont want to bin is not the scopes fault, nor your skies' fault. If you really cant survive the horror of a non zoomable image because it is binned, then why not mosaic? You have 4x the aperture, you can afford to take extra panels for a target and still land in a "faster" image than the smaller scope. Just a simple 2 panel mosaic will create an image large enough to be zoomable on a 1080p monitor, and will still be much faster than the small refractor. What is your plan here? So far not one of these sky complaint threads have had a conclusion.

Cant offer you the first hand experience you were looking for, but will say a few things that i can read between the lines of the product description anyway. The telescope is very cheap, suspiciously cheap even. Realistically you cant expect the thing to be a ready astrophotography platform when the very low price includes: The scope, plate and rings, an eyepiece, a finder, some adapters. The accessories without the scope will cost almost the 500€ this seems to be sold if of good quality. You should be expecting a factory standard newtonian which will require the usual modifications to get going, which would be: Flocking of the tube since the images seem to show a mostly gray rather than black inner tube, longer plate since the stock one is very narrow and you should expect stability issues with it. Might even want to add a top plate to tie the rings together. The tube seems to be steel from the stated weight of 11.2 which is good, so it doesn't buckle like an aluminum VX8 for example. The mirror cell could require some work if the mirror is not stable enough, or if it is too stable and you get pinching in the Finnish winter conditions the scope will presumably spend some time in. The scope is cheaper than just a 200mm f/5 mirror that comes with a certificate stating its at least "ok", so you should probably not be shocked if there is some turned down edge or similar minor aberration on the primary (that one is hidden with a primary mirror mask). Focuser might be ok, might be not. They seem to cling on to the hexafoc name in the description so maybe this is a strong part of the scope, if not, expect to get rid of it for again almost the price of the whole scope. Long story short, the scope is a third of the price i would expect it to be in order to trust it as a ready to go scope and you should probably expect to tear it down and modify it. The TS GPU 1.0x corrector is also a good option, spot diagram below: For comparison the ER one you linked below: RMS radius numbers are similar for both (ignore everything else, the images are at different scales), but a little bit flatter for the GPU which might translate to easier focusing and fewer noticeable differences in focus at the edges. The flatness part is good for a newtonian since slightly out of focus stars will have out of focus diffraction spikes, making the aberration immediately obvious. The HR diagram also only shows up to 15mm radius, while the TS GPU goes all the way to 22mm. From these 2 i would choose the GPU. And on the focuser intruding issue, it might, depending on how they have configured the scope and its focal point. It comes with an eyepiece and is shown in images with a DSLR so it has to be designed in a way that allows an eyepiece and a much deeper backfocus requiring imaging train to be at focus. Because of that i think the focuser will be poking out the inside of the tube a little bit since for imaging purposes the focuser would be racked in more than with an eyepiece. This will create either an extra diffraction spike, or some general diffraction messiness around bright stars. To get rid of you would be chopping the focuser tube shorter or pushing the primary mirror up the tube. Hope i scared you just the right amount and not too much so as to not want a newtonian. When/if it works well you get a blazing fast scope that i think truly can do it all or at least a little bit of it all.

I am assuming you are doing planetary/lunar imaging with video recordings with your kit? If so, take a look at autostakkert!3: https://www.autostakkert.com/wp/download/ It claims to work with Linux using wine, but have not personally tested this. If you can get it to work, look no further as AS!3 is much better than the aged Registax that is honestly a relic of the past these days. If you were doing longer exposure deep sky imaging, then Siril is the way to go for stacking and image processing for free with linux.

No such thing exists as fixed in place in practical terms. Not even for refractors if we are talking about same sized apertures and not an 80mm frac and a 200mm newton (very unfair comparison). Machining tolerances would need to be beyond all reason for every part of the telescope and imaging train to be "fixed in place" and even then a slight bump might undo it all. Its much simpler to allow adjustments in the design. Some cheap refractors cannot be collimated but that does not mean they dont need to be as you occasionally read in forums when a bad copy is sold.

There is also a Youtube channel that did a video on every messier object, highly recommend watching at least the objects you are interested in: https://www.youtube.com/playlist?list=PLC9FC5F6773B383D5

Actually the manual focus targets thing is apparently not visible by default. You'll need to click the star icon in the top right corner of the imaging tab to make it visible in the lower "tabs" type toolbar. This is in version 1.10, so its been there a while. Maybe its time to see what the newer versions have to offer.

If the end goal is 1.5" per pixel, surely there is no great need to have seeing or guiding to be as great as if you were planning on having 0.8" sampling?

Im with Vlaiv on this one, the C11 is the winner and with only a third of the time investment of the refractor it should be obvious as to how much better it really is.