speckofdust

Come to think of it, unlike a refractor, the need to clean the primary mirror at least once in a while and the process of remounting it will also introduce errors in alignment.

I am sure there is a good reason, but why is it not possible to make a reflector that has all the relevant optical elements firmly fixed in place so that collimation is not needed from time to time? Curiosity....thanks in advance.

signed

let's wait to hear from Moonshed.....😀

I have just googled the picture of smarties and a picture of 1 litre milk bottle ( only used to either 1 pint or 6 pint bottle, thats why) and my guess is about 1200.

Ah....looks like there was a misunderstanding, but anyway, considering the premise that people have seen the jar and the size of the candies before making the prediction, then intuition (!!!) tells me that this phenomenon is no longer an incredible one . I guess it is intuition derived from life experience after all, like estimating someone's height, speed of a car, muscle memory when lifting an object etc that leads to a ball park figure. The more people you throw in to make the guess, the extremely wrong responses are drowned out by the closer to normal ones, ie resulting in the normal distribution. Obviously this response does not contain any sound scientific evidence and invokes the nebulous concept of intuition, which nevertheless seems to be a good approximation.........

I think prior knowledge, however inaccurate it might be, plays a role. The participants would have to have seen the size of the jar and the size of the smarties to come up with a value that is actually close to the truth. If asked to guess the wealth of a random person, most people will say "tens of thousands", but the moment you say that the random person is a banker, the answer will change to millions. The rest is just Gaussian distribution.

Was mesmerised by the appearance of the sum this morning on the way to work through the "freezing fog" and just took a picture of it with the smart phone with no filters. Never expected to capture the sun spots, really pleased with this lucky !! imaging.

Hello all, on the recent processing I did for veil nebula, I could not see any effect from using the dark frames on Deep Sky Stacker. Not sure why. I have tried all the various options such as remove hot pixels, dark optimisation, kappa sigma, median kappa sigma etc, but to no avail. I have attached a selection of the image from a processed light frame and master dark frame ( generated by DSS). which show the same hot pixels. any help would be appreciated.

Thats brilliant, I feel this solution will work, will give it a go and feedback here. Thanks

Thank you, I will give this a go!

I am using zwo asi 1600 mm camera for imaging and zwo asi 120 mini for guiding, but what I have found is that these cameras have to be attached to the same specific usb ports on the laptop. If the cables are swapped around to usb ports, then the capture software (ASI Cap that comes with the camera) does not work and always chooses the guide camera and at the same time PHd2 would stop working. Does anyone know why this is so? Is it an issue with the software? Thanks in advance

absolutely stunning images

Wow, simply wow!! you can almost feel the fusion explosions fuelling the proms. well done and thanks for sharing!

Or we could try to match supply and demand. The vast amount of imaging data collected from the clear sky areas elsewhere could be outsourced over to be processed by people like me living under the endless cloudy nights in the uk. just thinking about the market forces....

the concept of time travelling terminator is a moot point, which forms the sci-fi premise for the tv series and the movie. a bit pointless to argue with that, but we can analyse the remaining aspects which are presented as science. Anyway glad to see that this has generated quite a bit of discussion and I have some ideas for me to determine the exact date if I were to wake up in the middle of nowhere, although I wouldnt have the appropriate equipment for some of the methods suggested above.🤔

but I am assuming that one needs to track the rotation of the stars for some time to determine the earth's axis of rotation and then see how far away Polaris is from that point. This process should take at least a few minutes rather than seconds even for a powerful AI?

Lol....I want that upgrade for my next telescope (without the Terminator functionality, of course!

In the scifi tv series- Terminator the Sarah Connor chronicles, there was an episode wherein a time travelling robot lands at around the 1950's and he looks up at the night sky to confirm that he has landed on the correct date. I am not sure how this is possible as in order to detect the difference in the parallax measurements, he should have a very powerful telescope that will be too big to be fitted into his eye socket. He would also need an extraordinarily powerful instrument to determine the shift of the Polaris relative to the earth's rotational axis. Is this assumption correct or is it theoretically possible to determine the date (year at least ) within a short period of time?

Thank you so much! really appreciate it

Really Nice. Can I ask how you find this object, as my hand controller only has IC and NGC objects ( and M of of course).

Best I could manage with my mobile phone, while clinging to the edge of a table.

Hello all, came across this issue 3 nights ago. I think it is ice forming on the ccd sensor, but not sure why it happened as the outside temperature was about 10 degrees on average through a 3 hr imaging session (started at around 13 degrees). Turned on the cooler on the camera for a target temp of - 5 degrees which was maintained throughout. after about 1 .5 hours the image started developing a weird shade at the centre. checked the objective, which was clear of dew. ( dew heater strap was on). looked down the scope and found a oval shaped area of fogginess at the centre of the CCD sensor, which I assumed to be ice. turned the cooler off and blew some warm air from a distance towards the camera and recommenced imaging after 10 minutes and after the fogginess was gone. The sub frame afterwards was good with no abnormal shade. So I presume this to be ice forming on the sensor, but its a bit weird, as I have not had this problem before and I have run the camera much colder at colder ambient temps. Any comments/ advice welcome. Thanks equipment- sw E80 ED refractor, camera asi 1600mm with Baader LRGB filters on zwo electronic filter wheel

what telescope are you using? Looks like a collimation issue to me.

oh ok, afaik, those files will have different pixel content, hence I dont think you can stack them. You can however use an image processing software such as adobe PS or GIMP to overlay them.