inFINNity Deck

Hi Nikolas, I have a 64bit Intel NUC7i5BNK, i5-7260U with 8Gb RAM and 500Gb SSD. The latter is slightly too small, I have difficulty keeping approximately 200Gb available for sessions. This sounds like quite enough, but when doing planetary imaging this is barely enough for half an hour data (so when doing RGB, it is just enough to create a 10 frames animation). The advantage of a NUC is that I also do all the processing on it using a remote-desktop connection: simply start the processing, close the connection and look a few hours later if it is done. 🙂 Speed-wise this NUC is fast enough to control the observatory, but for processing it is never fast enough... Nicolàs

Hi Knobby, I use one of these rubber strap wrenches. Nicolàs

The collimation of a RC8 has recently been discussed on this forum. Based in that discussion I made a step-by-step procedure for it, which I tested on a RC8 of a friend and gave very good results. The procedure is on a Dutch forum, but it will translate well when opened in Chrome. Nicolàs

Of I understood Padraic well this is M2 of Messi's list, so two more to go..... 😉 Nicolàs

Hi Aston, you nailed right there! Indeed the play in focusers (and 1.25" - 2" adapters) will always mess up the alignment. For this I only use the laser to get the secondary right (for my SW 300PDS that is) and then a Cheshire to see if the primary is fine as well (although I always start with a coarse check with the laser). When using the laser I always rotate it in the focuser, while keeping it pressed against it as even a well collimated laser may still produce a small circle when turning it around in the focuser (this may depend on make). I also test it in various focuser-positions as the focuser too may not always point in the same direction is my experience. In the end I aim at an average collimation. Recently I borrowed a Catseye 2-pupil Infinity XLKP Auto-collimation eyepiece from a friend and I have to say that collimating your scope with that is much more reliable. Please note that the altitude of the scope may also slightly affect collimation (it is noticeable in my 300PDS). I have no idea how well you should collimate to not have a significant degrading effect of it, but perhaps others may know. Nicolàs

Hi Mike, from the ASCOM-Help mail-list I understood that last night you "...downloaded a Fresh one [ASCOM driver], and boom... Telescope does telescope things." So may we presume that al is fine now? Nicolàs

My first SCT was a Celestron C11 XLT Carbon, which I primarily bought for planetary imaging. Reasons why I bought it were lack of spider (= no spikes, but in planetary imaging that seems to be marginal), aperture (= more detail) and focal length (=more magnification). Excessive mirror-flop and better optics made me decide to swap it for a C11 XLT EdgeHD as that scope has mirror-lock. It was at that point that I found out there is mirror-shift (play between the baffle-tube and mirror-tube) and mirror-flop (loose mounting of the mirror on the outer tube). Mirror-shift is something I can live with as it is only 30" at maximum (factory specs, mine has about 24"). Mirror-shift causes the scope to go out of collimation, so requires re-collimation as soon as the imaging session is interrupted by the meridian-flip. I returned the scope to Celestron for repair, but despite their promise they did not manage to repair it and did not even seem to bother (see my article on a Dutch forum, opening it in Chrome will translate it for you). Hopefully this year I will have it properly repaired. I anticipate that if that repair is successful I will have a great scope! As stated above I use the scope mainly for planetary imaging, but also for visual observing of planets and DSOs using TeleVue Ethos and Panoptic eyepieces (M13 is just great through it!). Nicolàs

Hi Mike, For what I understand an ASCOM driver is available for that scope. https://www.bresser.de/en/Astronomy/BRESSER-Computer-Cable-for-Remote-Control-of-MCX-Goto-Telescopes-and-EXOS-II-EQ-Goto-Mounts.html Stellarium should be able to control any ASCOM scope. Nicolàs

Perhaps it is good to mention that the pier is bolted down to the concrete floor using 16 M12 threaded ends with nuts and washers below and above the base. So instead of trying to pull the threaded ends out of the concrete by bolting down the pier, the base of the pier is clamped between the nuts and washers to avoid stress building up in the chemical anchors that hold the threaded ends in the concrete (so the base hovers a few centimetres above the concrete). The holes in the base are as close as possible to and on either side of the gussets to avoid further flexure in the base. Nicolàs

I can only agree with previous suggestions that you need gussets. I once made a very similar 1 metre tall pier like yours to hold a 120kg collimator and that swung around happily like an inverted pendulum, even though it sat on top of a 15 metres (yup, 15m) concrete foundation pole. The whole problem is the connection of the square profile with the baseplate. I used a 10mm steel baseplate under a 140mm square sectioned pier, but that was not stiff enough to avoid flexing. In the end I more or less solved it by adding three pressure points around the central bolt that held the pier in place and putting as much pressure on them as possible (it was a temporary set-up). That reduced the wobble, but not fully eliminate it, while it was far from ideal solution. When I created my observatory I needed a 3.4 metres pier to hold my GM3000 + four telescopes (total weight well over 150kg). That pier has 8 gussets: 4 tall ones going up to 2.5m and 4 small ones in between at the 0.8m diameter base (see below images). This pier weighs 270kg and shows almost no vibration (only when you hit it hard it trembles for a few seconds). Nicolàs

For those interested, version 0.2.0 of the SafetyMonitor Hub is now also available from my web-site. Main change is the way it connects to the underlying SafetyMonitors. The previous version created several unintended and unused instances of the connected SafetyMonitors. In this version no more than a single connection is made to each SafetyMonitor at all times. In addition the current version allows to access the settings of the connected SafetyMonitors, even when these and the Hub are already connected. It has improved status-LEDs and is now provided with tooltips. Nicolàs

Hi Iwan, ok, that post, thanks. That method does about the same as my method with the camera. My method has two advantages over the one in David's initial post: - it is not affected by misalignment of the laser; - it can be done without dismantling the OTA (although David's method may have been possible with the spider in place), only the secondary needs to be removed. In addition I think my method is more sensitive (but that has yet to be proven ;-)). In David's method the parallelism of the mirror with the wall is not critical at all. What happens, is that the mirror 'sees' the laser light on the wall and projects it back onto it, so even at a steeply inclined wall this should work (although being parallel may work easier). Nicolàs

Hi Iwan, The idea of taking out the secondary mirror is to use the screw-hole (that has the screw that holds the secondary) to align the visual back with the camera that stands in front of the OTA and at the same time to use this camera to see its own reflection in the primary mirror (in order to get that reflection properly centred). As long as removing the whole front end and replacing it with a template allows to exactly replicate the location of that hole and to still see the primary mirror, that would indeed be the same. The problem lies, I think, in that part "exactly"... Not sure which part of the procedure you are referring to, so please provide a link. Nicolàs

Hi Iwan, I agree with David, so please forget about the HG-laser and try to follow the methods described in this thread. The HG-laser is a fine tool for a final check, so after you calibrated the RC8, but is better not used for the collimation itself. A well collimated RC8 should provide a proper laser pattern, but a good laser pattern is no proof of a correct collimation. Nicolàs

Hi Brendan, I just ran a few tests (with 3 SafetMonitors in the HUB) and found that the HUB has an issue on my machine opening it's log-file. If that error message gets in the background it will not allow you to control SGP any more. Hitting ALT-TAB combination (perhaps a few times) should bring the error-window up. Hitting the OK button of that error-message will close it and the HUB works as expected (at least it does so here). Anyway, I will get this bug sorted, hopefully it will work flawless again on your machine as well. Will post here again once the new version is available. Nicolàs

Hi Brendan, the current version of the HUB is 0.1.1. I will have a look at it the coming days (it can do with some improvements anyway), see if I can reproduce your hang-up and, if so, fix it. Nicolàs PS: what was your third input into the HUB?

For those interested in automation: in the last few weeks I have produced another two new SafetyMonitors: Generic File SafetyMonitor Environment SafetyMonitor The Generic File SafetyMonitor monitors any ASCII-file(s) on the local hard drive or on the network, scans it for a preamble (e.g. ROOF) and a trigger in that same line (e.g. CLOSED) and sets the SAFE/UNSAFE event based on the user settings. The Environment SafetyMonitor reads observations from an ObservationConditions Driver (preferably OCH, but any driver can be used) and allows to trigger SAFE/UNSAFE events on 11 observation types in a maximum of 13 rules (the 2 additional ones are to allow for upper/lower limits for wind direction and temperature). Both have their own web-page on my server: http://www.dehilster.info/astronomy/ascom_environment_safetymonitor.php http://www.dehilster.info/astronomy/ascom_generic_file_safetymonitor.php Conform validation reports are included in the downloads. I share these with the community in the hope they are beneficial to other (amateur) astronomers. I can, however, not be held responsible for any damage done as a result of a wrong setting or failure of the algorithm(s) or of the driver as a whole (this also accounts for all other freeware downloads on my server). So, use at your own risk and feel free to redistribute it. I would appreciate feedback in case any bugs are found. with kind regards, Nicolàs

I must have missed this thread back in November, but I think that the OP would appreciate my 5 cents input. Last year I had exactly the same issue, but then with the combination ZWO ASI1600MM Cool Pro, SkyWatcher Esprit 150ED and ZWO 36mm unmounted filters. I wrote a thread on a Dutch forum, but that should properly translate when opened in Chrome. Especially the second image can be of interest as it shows the differences between the old style and new style ZWO NB filters, the old ones showing halos very similar to those by the OP: http://www.starry-night.nl/forums/topic/halos-en-zwo-filters/ So, in the end I got myself a new set of ZWO Ha and Siii filters and that solved the issue. Now, I know that the OP has a different make of filters, but using a similar methodic approach should make clear which part in the imaging train is responsible for these halos. Nicolàs

Hi Rusted, Thanks! Yours is nice as well. Making it tall gets you closer to the stars and therefore reduces seeing....🤪 For those who want to see more of my obsy, please visit my website: http://www.dehilster.info/astronomy/building-an-observatory.php You also wrote that "A round building has less room than any other shape.", but as long as we make it tall like you and I did, there is plenty room below it. 🙂 Nicolàs

Well said (should I repeat that threefold? 😉)! It is all too true. When I was creating drawings for mine, I searched the internet and the general advise was to go for at least 3 metres (10') diameter, so mine became that size (it also was the maximum the structure of our house could accommodate. A nearby public observatory has a 3.4 metres dome. The difference sounds small, but in fact is huge! When I first installed my 1490mm f/25 Galilean Type Telescope I found out it did not fit when mounted piggy-back, so I had to device dedicated mounting rings to squeeze it in between the two other scopes. With 3 metres (the drive ring on the inside is even less with only 2.8m) it is still possible to accommodate 4 adults or 1 adult and 4 to 5 children. Anything smaller will make it difficult to accommodate two... So if you can scale up, you certainly should! 🙂 Nicolàs

Hi Paul, If you really want a case (instead of a bag) I can recommend Peli or Explorer cases. https://www.waterproof-cases.co.uk/product/peli-1740-case/ https://www.protective-cases.co.uk/product/explorer-7814-gun-case/ They are available in many sizes, the above two are perhaps not the most ideal ones, being quite (too?) thin for a 4" scope. If you take a larger one, you might be able to have two scopes in it: https://www.protective-cases.co.uk/product/mub-78-multi-utility-box/ The padding is often optional. Nicolàs

Hi Adam, the 11 points will be separated by 30 steps each. The advantage of more points is that SGP has more data to fit the curve through and thus to correctly detect outliers. Downside of the 11 points is of course that it takes more time to finish the routine (11 images are taken). The instructions to calculate the step-size provide a good starting point. After the first run you will see whether you get a V- or parabolic-curve, but you should aim at the latter as that will match the parabolic fitting better. So if a V-curve is shown, it is better to slightly reduce the step-size and try again. From a physics point-of-view the HFR has a hyperbolic response (so all optics show a V-curve when far enough out of focus), the near-focus part of which can be approximated by a parabola. Implementing a best fit method is easier when using a second-order best fit instead of a hyperbolic fit and that was the reason why that model was implemented. Nicolàs

Hi Adam, I am using 6px at 1x1 binning on my ZWO ASI1600MM Cool Pro. Exposures are 7 seconds and are always taken in luminance. Nicolàs

Hi Adam, that screen shot actually isn't mine, but of one of the other guys together with whom we built this new routine (I was responsible for the automatic outlier-detection part). At the moment I have no screen dumps of my own set-up in action, weather permitting I will post one later this week. Currently I am using 11 points in the focus routine and, once centred, the HFR values lie between approximately 2.4 and 7-8. Here is one of my focus-runs from the testing stage, processed in a stand-alone application: The step-size of 15 is for my focuser, which uses a home-made 1:16 geared planetary drive on a standard SkyWatcher focuser (the OTA is an Esprit 150ED). So for the original 1:11 drive the step-size would need to be around 10. Nicolàs

Hi tooth_dr. The current version of SGPro uses a second order (parabolic) fit on the data points, so it is best to choose settings that make the curve look like a parabola and thus less like a V. Nicolàs