Green Baron

Concorde flew higher (50.000ft ?) because of drag (less density, less drag, less thrust needed). It only flew supersonic after crossing the coastline because of regulations. Sketchy spoken: besides improved behaviour during trans- und supersonic flight swept wings are a constructive feature that provides stability, mainly pitch. For an airliner this is a reassuring feature, in conjunction with a v-shape and a torsion in profile. A plane with straight wings can be more responsive and can have better gliding ratios. A multihull design seems not to be in favour of swept wings. Though, it's Burt Rutan, you never know ... :-) Judging the design, Stratolaunch is or will be a slow flying, high altitude plane with transport capacity.

Ediacaran and early Cambrian fauna are my favourites too. Animals from a different world.

What do you mean, betrayed ? dss is quite straightforward. Just choose lights, darks, biases if you have, click "Select all" and then click "register images". dss does the rest and saves a fits in the lightframes directory. Maybe try just the lightframes first ? You can stack manually with fitswork or pixinsight and will have my respect if you do so. You will have to walk all the way on foot, where dss offers a quick ride.

Very good question, i try a generalized answer. Ideally the chip's pixel size should exactly meet the telescope's theoretical resolution, so, yes 1:1 would be ideal. But most amateur telescopes do not reach their theoretical limit. Some high-end APOs might, reflectors usually stay way below (or above :-)). That's why some people still spend five digit prices for an APO while there is two times the aperture for a tenth of the price. Sadly one of the best manufacturers of air spaced triplets (LZOS) decided last year to double it's prices for fresh lenses and skip the small ones up to 120mm totally. Back on topic. If your camera offers a better resolution than the diffraction limit of your scope you have probably spent too much money on the cam because you will never use it really. We should have a set of different pixel sizes, because when using a compressor/reducer/barlow resolution changes :-) Also other considerations apply. Image field is probably the most important. Most chips are very small so that you only use the center of the image. It should have a size so that vignetting is not yet disturbing. And then the choice for us amateurs is limited. Even a simple ccd cam with a mass produced chip of the penultimate generation (example KAF8300), second choice batch, costs 1500-2500 funds new. High end full frame cameras easily go beyond 10.000, and still they have a mass produced chip you can accept or not. Second there is the atmosphere. It limits the resolution to way below what even a 4" telescope can deliver. There are the one out of 100 days where you can see in the enlarged pixels that the telescope/camera really was the limiting factor. But then again we do not have the time for this every 100th day ... In my case the combination telescope camera is a little below what the telescope alone (115/805mm apo) could theoretically deliver. The chip has a pixel size of 5.4 micrometers. So i am still a little better with the combo scope /cam than what the usual atmospheric conditions allow. I decided for this one because of my limited budget (i waited for a price reduction of the old generation chips) and the chip size / imaging field (right size for most nebulae and clusters, a little too small for andromeda galaxy). Of course i checked the pixel size, but image field was more important to me. Phew, hope that was an answer ... :-) Edit: sorry, the focal length of the tube is 805mm, but i use a 0.79* reducer. Now you can do the math :-)

Factorio. Great game. Can get arbitrarily complex. Got the hint here in this thread :-)

Raw is the only format we ever use. And ... exposure times are a strict Geheimnis i will never disclose :-) Seriously, look at astrobin, everything is open there. That's the fun part.

If it's only for the life view, my D700 dslr doesn't have live view either.I take exposures and look at them in 1:1 magnification, that's more accurate than the viewfinder, which in my eyes is too dark to see clearly anyway. Also, once your setup is balanced on the mount the camera will almost always be in the wrong position to look into the viewfinder, especially on a newton and you don't want to give up the balance. As said before, use a focusing aid, Luke. A Bahtinov-, Hartmann- or Carey Mask which you can cut out. Use it to get close, and then a few exposures to focus sharply. That is more accurate i think and you only focus once and then fix the focuser with a screw. I practiced last summer with the cam on a simple tracking mount and telelens and found out that mirror pre-release is a must. Also i would strongly recommend a cable less timer for the cam, much more than life view ! Fingering at the release in the dark and cold may results in cursing. My ccd's capture program uses a method called full width half maximum (fwhm) to calculate a value for a marked unsaturated star. In principle, if it is small and bright it is sharp, if it's large and dark it is out of focus. Maybe, if you get a cam that you can connect to your pc, you can find a program that does something like that ? I do not know though ... as said, bahtinov mask and test exposures ... it's so easy with the electronic stuff these days :-) Visit astrobin and see which cameras people use for astrophotography. These are usually not the newest models ... Edit: search "focusing dslr astrophotography". Everyone recommends the Bahtinov mask. Everyone. :-)

Cool. This may be a stupid question because i lack the understanding, but how can a single apparently directed light pulse be seen from the side ?

Let's wait for your first exposures. You have a nice newton reflector there for a very reasonable price, given the opening and focal ratio. Also i like the steel tube more than the modern plastic (carbon fibre) ones. It is better suited to bear a heavy camera. An astrograph is not defined sharply. Usually one understands an instrument that has a corrected and flattened image for measuring distances and angles between objects, to get their exact positions in relation to fixed stars. This is what one needs when somethings new is involved, like discoveries of dwarf planets, asteroids, etc. Ideally the correcting equipment of such a thing is designed for the use of a special chip, to meet exactly its resolution (via pixel size) and plane. Usually one does not look through such a thing. It is mounted somewhere in a dome, accessible via cable and scans the sky all night long (yeah) :-)

Why not contact a manufacturer of industrial transport things or weighing equipment (scales they are called) ? I could imagine that there are enough solutions to choose from ... my uncle had factory for transport equipment ...

Visual is usually along the axis you will not need a cc if you are content with the view. fotographic is in the field as well. If you have coma in the corners of the picture you will then need a cc. If you use 100 or 120 degrees app. fov eyepieces then coma might get disturbing as well :-) Edit: am on a reasonable pc now and can type ... Visual observation occurs along the optical axis. You point at something, center it in the eyepiece and watch. So you will not notice any coma because that is out in the field of view, the farther away from the optical axis, the stronger. Only if you use those nice 80, 100 or 120° eyepieces you will probably notice the coma at the borders of the view. Your instrument has an imaging field a little smaller than an aps-c chip, as written in the specs, which is absolutely ok. Most dslr cameras have a chip in that area, which is roughly half the size of a so-called full frame chip, the format the old analogue slrs had. If you want to find out if you need a corrector: connect your aps-c -size camera and bring it in the primary focus (no correctors/filters/glass) using the correct adapters (see the manual, most probably a 2" or M48->T2 and then T2->bayonet of the cam or, if available, direct 2"/M48->bayonet), focus the center sharply and shoot. You will then have an image that is sharp in the center and shows more or less pronounced aberrations in the form of prolonged stars or stars in the form of "pears" towards the darker borders. It is these deformations that you would want to correct with a coma corrector. Hope that helped in your decision making :-)

If that earns it's designation of being an astrograph than some sort of field correction is built in ... ? Edit: hm, orion offer a corrector for their newtonians. I would take that one. The televue paracorr has a good reputation. But take your camera with you to get the right set of adapters and correct distance. This is submillimeter work. Maybe try without first ? Sorry for being short, am on my tablet ...

Wow, am astonished how many people actually speak at least a little German. My neighbour learns German, i learn Spanish, because i have moved. German with a German accent, English with a German accent, Spanish (well, cough, ... trying hard) with a strong German accent. I won't starve in France or Italy but i can hardly speak freely. Typical European ...

So am I !

*rofl* op, you are a funny guy :-) Also, asking for manpower/resources isn't really science & spaceflight ... imo.

Don't use heaters, you only cause turbulences in the tube. Leave it in a dry and cool place during day to reduce the cool down time. Here the difference is only 5-10°C between in- and outside, yet i put my stuff out in the shade when the sun goes down and give it 2 hours, and refractors are said to cool down much faster than reflectors. If there is too much moisture in the air then i try another day. The seeing conditions will be bad anyway. In this climate here water may be dripping from the tube, time to give up and do something reasonable instead like play ksp ...

Well, a webcam is what many people still use for moon and planets and in principle a guiding cam is nothing more than a good webcam with a little more software. Single shots do look like that. Try a video sequence of a few minutes, push your dobson manually, the bad frames will be discarded later. And then feed it into registax. Maybe i try it too today with the guiding cam, just to be able to keep up with you guys :-). I only don't want to dismount my equipment because it's all adjusted for DSOs. I'll have to get the old newton out of the cellar, free it from dust and adjust it ... where is my laserpointer ... ? Edit: oh, this may be a stupid hint, but give your reflectors at least a few hours to cool down when you take them out of a heated interior into the cold. That'll make a big difference. If you have an adjustable main mirror mounting the main mirror should rest with a little clearance, so that it could be turned by hand or a thin sheet of paper fits between mirror and rest. Most people fix the screws tight just because they think that is the way ... I hope this wasn't too impertinent.

Good news :-) I wanted to do this in spring, but i did a search now. There seem to be a lot of registax tutorials. Example http://www.astrotarp.com/Registax_basic_tutorial.html Also i believe registax has some sort of manual, the foreword in the link says that. It seems like there is a frame grabber for avi built in registax, so i hope you have avi. If not maybe you need a conversion software, or registax can extract the frames out of other formats as well ? Hint from an amateur: before you gather data be sure that your planned workflow (the steps from data aquisition to presentation) understands your data or you might get stuck in the middle of processing, contemplating the evil in the world :-) Sorry for not being more helpfull right now, if the tutorials do not help and you get stuck i'll try and dig deeper.

Hehe, i shortly read a humorous text that tried to answer the question "Why are the vast majority of moon photos from a crescent waxing moon ?" (sorry, bad english, i meant the phase between new and full moon ...) As far as i am concerned, the morning hours are not my most active phase ...

@ProtoJeb21: like @_Augustus_ said, Registax and hundreds of exposures or a few minutes video. At least that is how people do planetary imaging. You need a high magnification and a videocamera. A cheap one is enough or maybe your phone can do video. I must admit i still have a phone that i use just for calling If "copies" mean that you copy a single photo that will not work, they must be different. A tracking mount is helpful as at the high magnification the planet will just race through the field of view. Maybe you will become a master in greasing the rockerbox of your dobson and pushing it manually. Should work with video sequences. You can experiment with the moon to see the difference between a single shot and the stacked video sequence. I have not done it myself yet but it's on my list for the spring, maybe we can exchange our knowledge then :-) @Veeltch, well, try it out.If it works ... i didn't mean to talk old ...

http://astrosolar.com/en/ Why risk health and material ? Yeah, you can burn your eyes. It is not the bright light, that will make you turn away quickly, avoiding damage. If you use a homemade film it may look dark so that your pupils are wide open, but hard radiation is eventually getting through, you cannot see it directly but you damage your eye background while looking through. So, clear answer, do not tinker with untested material if you value your health :-)

Ages ago i have taken photographs with infrared films (other side of the spectrum :-)). Nice for landscapes. Roentgen radiation (x-ray) is a broad spectrum between uv and gamma radiation, much broader than visible light. You'd somehow have to convert it to a visible light spectrum and send it to a ccd. I can imagine that this is a challenge for an amateur, but i do not know. As for film, it's expensive these days and the chemicals aren't always available anymore. You'd probably have to mix your own soups or buy expensive ready made stuff if available. If you think of medical equipment, they use a radiation source for exposure (cesium or something), a "bright shining light" sotosay. I can imagine (but i do not know for sure) that medical equipment is simply not sensitive enough. Also, with film you have one shot per negative that might cost at least a few funds per shot and development, and that's it. No delete and redo (F5/F9) like these days :-) Sorry for shouting, it is not my usual habit, but IF YOU LOOK AT THE SUN ALWAYS USE A SOLAR FILTER ! You'll damage your eyes and your telescope from the heat. Solar filter foils are available at astronomy shops. Get a sheet, cut it out and fabricate a sturdy frame (plywood) to cover your front lens or opening so that the filter cannot fall off. Additionally, you can use projection on the other end on a white sheet of paper or so. I am sure you can find examples. For solar photography people usually use narrow band filter, like hydrogen alpha e.g., but i fear these interference filters are extremely expensive (200 funds a version with just 48mm diameter), and before mastering narrow band maybe the "normal" rgb-techniques should be mastered, because for presentation it is all about combining the wavelengths to a nice and shiny colourfull picture :-) See astrobin for examples ... Ok then, i'm looking forward to what a phone camera can deliver these days :-) You are right using adapters, it will make it a lot easier to find the focus and hold still. If you need help with that try bahtinov- / hartmann- /carey-mask that you can cut out as well, no need to spend money for that.

No, you are not missing something. This is a premature question given the fact that the whole thing is nothing more than a concept paper and a presentation with a few funny aspects (like stealing underpants) and a length if you want. Which maybe totally different once things become clearer. Nothing of the ITS really exists and assuming that anyone yet knows when, where and if there are doors, ladders, crane on a traveller or whatever is like imagining a door without a frame. Once it is clear how to build the ITS at all a ladder/crane/whatever can be put in the appropriate place. Edit: ... and, by the way, the door / cargo hatch is clearly visible on the first photo. The ladder is probably part of a mod. No pet peeve here ...

Where's the ladder ? How often have i slapped my forehead ... were's the ladder :-))

"predicts" is the right word in this context :-)