JamesF

I agree with Stu. If you feel the need for a smaller aperture having made the full-size mask, you could always make a disc with a hole to place over the top of the filter, perhaps even in several different sizes to see what works best. James

Is there a description anywhere of what "CMOS-optimised" actually means? I've been unable to find anything. James

This is so true. People often look at me as if I have two heads. James

I've tried both the addresses I have now. The first didn't appear to receive a response, perhaps because it's no longer read. The second (his work address, as far as I know) bounced. I hope that Chris is well and just busy rather than the project being effectively dead. I know he planned to open the source at one point, but I don't believe that happened and we may be stuck for the time being. He was confirmed as a speaker at a planetary imaging workshop last year, but that didn't happen for obvious reasons. James

As far as I'm aware, you can't use a wedge with a reflector (which is why I still have some film filters for use with my 127 Mak) for precisely those reasons. I believe the greatest danger whilst using a wedge is setting fire to one's tie (you do wear one whilst observing, don't you?) because it dangles down into the path of the majority of the heat/light that the wedge is rejecting. James

I generally use a wedge these days, but my Baader film filters are fairly flat, though they're not under tension. I just lay the filter on the table and then gently placed the carrier on top to fit it, as far as I recall. I am wondering though if the reason flatness doesn't matter for the film is that it's only a few wavelengths of light thick (about 10µm, I believe, compared with about 0.5µm for green light), so refraction effects in the medium of the film are small, or perhaps the film just has a refractive index close to 1. I've not ever had a glass filter in my hands, but I assume they're several millimetres thick and probably have a refractive index somewhere in the region of 1.5, meaning greater distortion of the final image due to refraction if the surfaces are not flat? James

I think perhaps you've over-extended my metaphor I'm just quite relaxed, comforted even, about knowing that we are a very tiny thing that's part of an inconceivably big thing. I might be more concerned if we weren't aware that anything existed beyond the solar system. Life would indeed feel very fragile then. And perhaps it is a little extreme to suggest that we have zero effect on the universe. We've been sending radio signals into the universe for one hundred years and the first man made object has left our solar system. It will be followed by others. One day, somewhere, "someone" might discover that. And what effect might that have, even if we are long gone? James

Oddly enough, exactly the same thought occurred to me James

That's a nice illustration. Especially if you mentally move the rectangle over Mare Crisium or Mare Humorum. I reckon they're pretty close to the same size as seen from Earth, so if the Moon is in the sky it gives a nice indication of the amount of sky in the image. James

I think it's going to be very hard to get good images of Saturn and Jupiter until they're higher in the sky and if you have better uses for the money then they'd almost certainly be better uses for the money Used equipment that is mostly for planetary imaging might be cheaper at the moment though, because fewer people (in the northern hemisphere at least) are looking to buy it, so there may be some bargains to be had if you don't might spending the money and not using the gear very much until the planets are better placed. James

There are some that genuinely are spirals, which work fine but can be a pain if you need to add or remove cables. There's also a variety that is more like those plastic document binders with "fingers" that you can get, so whilst the cables are completely enclosed they can be pulled straight out. That always seemed like a good idea to me, but I can never remember what they're called, if indeed they have a particular name. James

I've always loved the image, and personally I find it quite reassuring. Whilst some might find it a bit like going into the Total Perspective Vortex, I think it's a joy to know how we fit into the universe as a whole, even if it does mean the entire human race is no more significant than a single amoeba in all the oceans. In some senses it gives me a great deal of hope, in that perhaps if we don't manage to avoid self-extinction then all of life's eggs may not be in one basket and there could be examples somewhere out there that manage to avoid a similar end. There is however a sadness that we can only explore all this amazing stuff with telescopes and may only ever be able to do so. My one absolutely compelling reason for living forever would be so that I could meet a technologically advanced extra-terrestrial species James

And yes, it does appear that they provide their own SDK: https://www.get-cameras.com/requestdownload James

The web page says near the bottom of the spec details that it uses the USB3 Vision/Genicam protocol. In my experience that usually means the vendor also provides their own SDK that's required to communicate with the camera (Basler has Pylon, for example, and TIS has IC Imaging Control, whilst whatever FLIR -- Point Grey as was -- are known as these days has Spinnaker). It's possible that Firecapture or Sharpcap has included their interface, but seems unlikely. On Linux there's also a generic Genicam interface called Aravis, but as far as I'm aware it still doesn't support a lot of cameras (and hasn't been tested with any from this manufacturer that I can see). There may be something similar for Windows perhaps? They do appear to have their own software package, but it may well not be suitable for astroimaging and it costs twice the price of the camera No issues with raw format with this particular camera though, as it's mono. Genicam does however allow raw frames from colour cameras to be made available to the user, but whether the SDK developers choose to make them available is a different matter. And of course if someone would like to provide me with a camera, I'll try to get it working with oacapture etc. on Linux and MacOS James

I've emailed the author with a reference to this thread as it looks like he's not signed in on SGL for almost a year. If there's no response after a couple of days I'll try a different address that I have for him. James

Do you also get the "Bad CPU type" error? James

For some time now I've found that Libre Office is a sufficient substitute for MS Office, though it/Open Office used to be a bit ropey in places. I'm hardly an Office "power user" though. As long as I can read files that people send me then it's all good. I've only had a brief flirtation with the dark side though, for a few months on a work project that never came to fruition. Other than that I've used UNIX or Linux pretty much exclusively for the last thirty-five years, since I started my (Computer Science) degree. James

I think vlaiv's answer more than demonstrates why asking this question does not make anyone look pretty stupid James

What could possibly go wrong? James

I don't think they crashed, but I can't find a copy of the book to check. Perhaps I never had one and just borrowed it from the library. Wikipedia doesn't mention a crash either: https://en.wikipedia.org/wiki/The_First_Men_in_the_Moon James

Ah, jolly good. I couldn't find any close-ups of the wheel fixings, but I can certainly take some if it would be helpful. Just let me know. James

A few pics of mine during construction that might help (possibly some of the photos from the weeks prior to this might help to show more about how I did it all): I used this track: https://www.fhbrundle.co.uk/products/0587604000__3_metre_Track_for_V_Grooved_Wheels_in_galvanised_steel and these wheels: https://www.fhbrundle.co.uk/products/0586604000__80mm_Dia_V_Groove_Wheel_One_Ball_Bearing_Internal_Support James

That looks fun Surely Cavor and Bedford beat Tintin to the Moon though? James

Now there's a place I've seen so many times in the twilight, either on the way to or returning from swimming competitions at Millfield. It's never looked quite like that though James

Aside from getting my vote for the most novel use of a scissor jack since they were invented (even putting it ahead of my own use of one in an apple press), I'd like to ask: what is the above tool in the drill chuck. I think I can honestly say that I've never seen one before. James