Whirlwind

Yes I finally got to see the Aurora now I've moved North.  Exciting to see it for the first time!  Here's my iphone attempt...

What about St Helena if you are looking for something in the Southern Hemisphere but want something a bit "home from home".

Though not the easiest to get to.

53 minutes ago, Leo S said:

Great catch. They were mentioned on spaceweather.com. Just for a moment there I thought they might have been visible here, after seeing your location (Leicester)!

Yeah, sorry I've just recently moved up here for work.  Just stepped out the car and there it was!

There were some Nacreous (mother of pearl clouds) that were displaying yesterday evening and this morning.  Here is my attempt just before I went into work (Dingwall, Highlands). 

Very strange how it just stood out in an empty sky.

17 hours ago, Horwig said:

I was under the impression that the rate of cooling was influencing the creation of dew, hence slowing down the cooling was the way to go, but maybe I was wrong.

No it's nothing to do with rate of cooling (other than how quickly it will form).  It is at a simplistic level a combination of humidity and differential temperature.

If you have high humidity you need less differential temperature for dew to form.  If you've had some particularly wet weather the humidity will be higher so it is more likely to form on a cooled surface. 

You'd probably want to test both and see which you prefer.

G2V is calibrating against a sun like star whereas SPCC, from my understanding, is looking at your image and determining what the colour calibration should be against a "standard" galaxy colour.  There will be differences to both really.  It would be interesting to see whether either fall down in non-standard conditions though (for example a narrow field view of a cluster of hot stars etc.)

I don't think you need to change the individual exposures though for the different colours as you can just change the ratio of the number of exposures I believe.   However strictly speaking you should expose a G2V on the same night / same area as your target etc.

SPCC is ultimately simpler but arguably is processing based rather than your own "data" based.

I've got a place at Pixelskies but it isn't yet set up (waiting for a mount).  But they've always been very helpful and communicative.  Have no experience with E-eye.

There's another hosting firm in Spain here as well (again no experience):-

Telescope Hosting - Trevinca Skies

I'll send you a PM separately.

Cheers

6 hours ago, icpn said:

I think as one of the vendors there I can say that the turnout was very poor. Friday was almost dead, certainly the afternoon. Saturday was better but  the number of vendors was down and the turnout from people attending was well down on previous years which was disappointing given the three year break. Whether this is due to the economic situation or the lingering issues with Covid I don't know. Certainly given this I doubt we would attend next year if it occurs. At least compared to PAS which was entirely an imaging event there was a wider range of kit to see.

Yes, it was quiet compared to when I was last there in 2019, though I did spend more this time as I'm about to move to the Highlands and wanted to get a grab and go set up as it won't be until next year until I have a property I can put an observatory down in.

However, I'm not sure PAS2023 will be any better as I tend to think the quietness is largely down to the economic circumstances we find ourselves in.  Even those with more money to spare (and astronomy favours those with deeper pockets) then they are going to be having to consider mortgage increases, energy bills etc.  And this is before considering everything has increased in price and there are less discounts on offer etc.

There are some fundamental issues I feel though in that:-

It was held a week or two before half term.  Holding something on Friday when most families will be banking holidays for the following week(s) doesn't make sense - this then only encourages older people to turn up.  Even though I was there on Saturday midday'ish  until early afternoon, I barely saw anyone younger than me not on a store (there were a few).  Hence, I don't think that helped attendance.

I think there should be an effort to make it more 'family friendly' in terms of getting more activities that younger people can engage with - That might mean engaging with universities and the like to try and do outreach activities.  Although I appreciate RVO want a full room - I think this could be better set up for this area.  The talks could also link to these outreach activities as well.  Also because you would have mini-speakers it might become more interactive.  For example perhaps holding a spectroscopy event (which might then make people think about doing some of their own).

Hold it earlier in the summer - by mid October I have pretty much sorted out my set up for the winter season - I'm less likely to be looking for things in October.  This would also potentially allow outdoor activities (weather dependent) - e.g, solar observing, moon observing if linked to first quarter etc.  I recognise FLO tried this partially with remote viewing but it was tucked away in a corner as well (really could understand this at PAS - might encourage people to buy a solar scope.

I don't think paying for the talks separately is a good idea for a niche hobby - to go to all talks would cost nearly £40 each.  In my view it would be better if the talks were included - so even if you brought the family it wouldn't be prohibitively expensive (especially if you have kids 16+ that might be interested).  Personally, I'd prefer to pay a bit more and have free talks (even stream them for a small cost).

The site is easier to get to though, so that is a positive.

Just my thoughts.

10 hours ago, Northernlight said:

Ok maybe i have - but have any customer actually had their mounts delivered ?

I think Peter Shah has one now set up.

15 minutes ago, Xilman said:

As I understand it, which may be imperfectly, the use of a R filter can reduce the noise (from sky and from seeing) by more than the signal compared with unfiltered.

As for binning, I generally use 2x2 binning on the images downloaded from the camera. It doesn't reduce dynamic range but it does even out pixel-to-pixel sensitivity variations and it does reduce noise.  My advice: bin in time only if absolutely necessary to get the SNR. With a transit what is much more important, in pracfice, is precisionin  the orbital elements rather than in the size ratio of planet to the star. The former requires precise timing, the latter precise magnitudes.

I'm working on the principle and looking at the website that they are doing follow up detections.  Many of the space telescopes and even ground ones focus on cooler red stars.  Not only are the stars smaller, so transits have a larger impact they also occur more frequently.  On top of this their habitable zone is a lot closer to the star (so it's easier to identify potentially habitable planets).  Hence there is sense on what they are telling you as I expect many of the follow up stars are M and K stars.  Once you start to get hotter stars then a lot more flux is outside, what I assume is the R band filter.  Hence there is a balance that yes, red filters do reduce your noise but then you are also filtering a large fraction of light in bright, hotter stars.  However from a guidance perspective one simple message for the public is easier to explain.  It also ensures greater consistency of data (is the depth change because of noise or because it is a binary etc).

Yes, binning in time is for higher SNR, for most observatories (barring very large telescopes) you generally run multiple observations of the same object over and over to get the precision as you can phase fold the data.  But again the consortium are doing that with the various data sets I assume (again preference for consistency would be key in this approach).  On the other hand if you are doing it for 'fun' and just want to evidence you captured the object then time binning is likely to show the transit easier. 

On 26/06/2022 at 19:11, Xilman said:

I have been recommend to use a R filter to reduce sky brightness and seeing. If you can't get a high enough SNR and cadence filtered, use unfiltered.

 

For exoplanets you really want as much signal as you can get.  I think this might come from the principle that many short period planets are around cooler stars as even at short periods they might be habitable.  However around brighter hotter stars a red filter is just cutting out flux more than any benefit you will get from seeing or sky noise issues.   There is some benefit from using filters to identify binary stars (as depths will change dependent on the filter band).  But really you want as much signal as you can get.  If it is noisy just bin your data in time (not on the camera).

Also think you are doing something wrong in astroimagej as both your assessment are putting your data half a phase out of where the eclipse is.  So your T0 has been shifted for some reason.

2 hours ago, AMcD said:

That is a very good point.  The short answer is I do not know.  I find AstroImageJ a very complex programme to use.  I am quite new to this aspect of the hobby and at the moment am at the 'follow what it says on YouTube' stage 😀

My lack of software prowess is probably demonstrated by the fact I have spent most of the day trying to install HOPS, as kindly suggested by @Xilman, via repeated reinstallations of Anaconda without success.

Annoyingly I've just tried installing it all and it's gone through fine (and I'm not aware this computer already had Python installed).  So can't really help here.

As a question, why does the second line (bulleted on plot) say Kepler 408b?  Just checking you are using the correct model as I wouldn't expect it to have been this far out when you modelled the system.  Are these data points binned in time?

Sorry, missed this initially.  Yes I use Prism and do also like it being an all in one solution.  However, quite pricey compared to things like NINA I suppose for most (unless you want some of the bespoke options).  I think it is based off professional observatory controls from what I recall has been said (but then for most they don't need that).  The interface is a bit clunky though compared to things like NINA/Voyager.

What was the problem with the guiding as I've not had any problems (barring my own setup mistakes)?

On 03/05/2022 at 13:33, The Admiral said:

Are we sure cable tangle isn't going to be an issue with these mounts...?

On 14/03/2022 at 16:10, Magnum said:

Even if cmos is as good or better ( thats debatable ), I think the statement CCD is dead to be ridiculous, our existing CCD cameras don't just stop working lol, and I would happily buy a another 2nd hand CCD, I already have 2 mono CCD's and 1 OSC CMOS and really don't see a big difference at this point they are both good and im happy using both.

"CCD is dead" really aggravates me and something I see quoted by the retailers that only sell cmos. I really can't see why any end user would want to be saying that when its not true at all.

Cheers

Lee

From the perspective new development for the amateur market the era of the CCD is generally over.  For science / specialist applications it is still going strong and there are pros/cons for both when used in this way.

The problem for amateur astronomy, is that CMOS is more adaptable - in effect there is no reason to develop CCDs from a business perspective.  Which is a shame as I imagine the new tech in CMOS if it could have been transferred to CCD architecture would have brought them up to similar standards in terms of read noise/sensitivity. However this is not going to be an option (unless you win the lottery). 

However CCDs will be around for many years to come, and will still provide a strong showing against CMOS cameras.

2 hours ago, spikkyboy said:

Hi, does anybody know of or at least think that its high time that we were blessed with a self aligning EQ mount?

I have a HEQ5PRO mount and really struggle with alignment. The slightest amount out of level before you start and the object you goto is 2 inches higher than the field of view. Not even getting started on being down on my knees looking for Polaris. I bought the Polestar alignment camera and this does help but HEY if there are any mount designers or perhaps a rep from Sky Watcher reading this come on its 2022.

Thoughts please ........GO!

Avalon Instruments do provide this with some of their setups but there is a cost to it.

M-zero obs | Equatorial GoTo mount (avalon-instruments.com)

I wouldn't worry about it too much.  There are a lot of catalogues out there and photometry and astrometry has used more developed code (and better resolution images) over time.  Hence old catalogues might have identified the object as one star but later as two stars - which is why you now see it in such programs as three stars when you load multiple catalogues.  

The Gaia catalogue is the best source of data these days.  This shows only two days.  They are about 842pc (+/- 26pc assuming three sigma error) and 884pc (+/- 29.7pc assuming a three sigma error).  Their proper motions are also very similar so there is a good possibility this is a binary system but longer observations are really needed to be conclusive.

1 hour ago, centroid said:

I will give it a fair try Olly, but does seem from what I am hearing, the 2600 is a much better option than the 294.

From what I can tell each CMOS camera has its own unique 'oddities' that have to be dealt with.  From what I've read the 294 needs careful flats because of the way its pixels are structured.  At the moment there isn't one comprehensive 'manual' to ultimately calibrate them.  The 2600/268 are most 'CCD-like' in this regard from what I understand.

17 hours ago, centroid said:

That said, call me a sceptic, but I still think that the CCD was much more 'user friendly. No severe amp glow/starburst, no black level, or gain setting to get right, no green colour cast, and no other strange colour renditions.

I do see some very odd colour images posted, having been taken with CMOS cameras.

Yes, I know they are cheaper, and more sensitive, but imo, compared to CCD, that is as far as it goes.

However, it is early days for me with a CMOS astro camera, that use re-purposed senors, not designed with astro imaging in mind.

I will see how it goes, and I can always go back to a loved, and trusted, Starlight Xpress camera. I note that FLO still has a good stock.

Terry Platt of Starlight Xpress, always provided excellent customer support, with their manufacturing based in the UK, and not China.

There may be other factors as well.  From my own experience light pollution has got worse (not just brighter but now with greater use of bright white LEDs etc it is less easy to control.  The weather may have also played a part as last week was very misty/foggy which would both scatter more moonlight/light pollution more as well as reducing photons from space getting to us.

I don't think you can see CMOS as an improvement but just a change compared to CCD.  I too find that calibrating CMOS images is more of a chore compared to CCD.  I think this is down to the greater stability in CCDs compared to CMOS.  I've never had a problem calibrating CCD images but do so regularly with CMOS (a 183MM currently but am going to test a QHY268M shortly).  For example take a wide field image I was playing about with last week (1.57 hours total 94 x 60 secs on a stock canon 18-55mm lens using a 6nm halpha filter - please excuse the trees on the left!):-

Despite being calibrated there is still obvious banding remaining (the vertical element abut a third way from the left being particularly obvious, although there is less obvious horizontal banding).  I didn't get flats with this set up (I was really just testing a wide angle arrangement) but am not sure yet whether this effect will be corrected in this way.  The bias/darks have removed a lot (see below of those master frames)

In particular these have removed the amp glow but trying different combinations (with/without bias etc) leaves some banding so is either a flats issue or something that won't calibrate out (meaning either dithering or potentially longer exposures maybe).  Otherwise I have to use processing to remove it which ultimately does impact on the final image quality.

I hence do recognise the frustration compared to CCDs, however amateur CCDs won't be around for much longer in all likelihood so starting to learn the oddities of CMOS is likely going to be needed (though like you I am tempted to pick up one last CCD; although they are likely to left behind in the long term as CMOS should be able to be developed to allow part of an image to be used for guiding in the future, as an example).

Nevertheless the ability to take shorter exposures is a benefit placing less constraints on the mount you can use and can work in conjunction with short focal length instruments well that are 'weighty' which in the past might have needed more expensive mounts.

1 minute ago, vlaiv said:

If you bend cables into semi circle - you'll do the same - there is no need for special mask and blockage of the light.

Diffraction happens on a straight edge - in direction perpendicular to that edge. If you make edge curved - each little section will diffract in direction perpendicular to it and if you have semi circle - this will spread in 360° effectively creating halo rather than one strong spike.

Just make sure you have semi circle and not semi ellipse or otherwise you'll end up with elliptical halo around bright stars, see here for discussion on that:

Yes, sorry I was aware that you could do it this way.  I was thinking more that it provides a structure to attach the cables to.  As noted if you get it wrong it has effects.  If you have a mask template that fit around the opening then you could attach the cables to backside of the mask to hide them completely and providing a known attachment path (rather than trying to arrange the cables in a certain way that might then move during imaging etc).

It depends on what you are trying to achieve.  Although it is larger the f ratio is similar; you are hence just spreading a similar amount of light per pixel (as the focal length is increased), you won't get brighter images because of it.  All you will be doing is increasing resolution at the expense of the field of view.  To capture the brighter image you would need to bin the pixels (but it is OSC camera so isn't really relevant here as you will lose the colour data). 

On 11/01/2022 at 08:54, Annehouw said:

I have experimented with that, and they do work. There is a slight downside in that it will take away a bit of contrast.

In the end I decided not to use them. I do not dislike spikes anyway.

 

I wonder whether they could be used on a RASA as well to hide diffraction spikes from cables that would otherwise cause no symmetric effects?

2 hours ago, d-s-m said:

@Sunshine yes I thought about switching the car lights off, but wouldn't that be a bit dangerous? Especially if it's a place that is very dark. I guess half beam would be a good compromise, but still has the potential to spoil other people's night vision.

I don't think I'd recommend anything that might be considered dangerous driving if there was an accident - you might get both be prosecuted and your insurance may not cover any damage.  At professional observatories you would turn off the headlights and use the hazard warning lights (but again not recommended for general roads).

I think you should just operate normally.  If it is an organised event then there will probably be site rules anyway (must arrive before a certain time etc).  On a public site you'd have to take the risk that random people will turn up with other endeavours in mind anyway (private solicitations, dog walkers etc) and they aren't going to be bothered about keeping headlights down etc.

Sorry, but I think we would have heard about it before.  Astrogeologists have been studying the moon for decades.  There are volcanic features but they are more akin to low explosive type of eruptions that we get on earth after factoring in the lower gravity (something akin to recent Iceland volcanoes).    

However an immediate problem does show itself in the Prinz crater.  If we at least speculate that very explosive eruptions (i.e. a supervolcano) can exist [which would be weird anyway because there is nothing between the non-explosive to super explosive which you should expect] then we do know that:-

A volcanic crater occurs when the magma chamber under the volcano empties and the overlying rock is no longer supported and hence then collapses to fill the void.  As such you this only occurs at the end of an eruption.  The rilles (likely being old collapsed lava tubes (definitely not water formed!) would be formed whilst the the volcanic chamber is emptying.  Hence the crater should be younger than the rilles.  However the rilles are emplaced on the old flood lava that partially submerges the Prinz crater.  As such the rilles must be younger than the crater.  This rules out that the rilles arise due to Prinz being a 'supervolcano'.

There is likely a lot of other evidence in terms of heights etc, but generally the advice is that just because two events are co-located doesn't mean they are in any way linked.