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Hi - Am new to all this stuff so help on this DSS staking blocker would be much appreciated - done a load of googling but need to know if my hours of FITS are scrap
Setup : ASI183MC - Sharpcap 3.2.6480 (Live Stack for lights, Capture for Darks - no bias or flats yet)- DSS 4.2.5 - Win7 64bit-USB2 - CEM25P - no guiding yet
I managed to get Sharpcap into a mode where it was saving individual RAW Fits files for Darks and only the Stacked FITS for Lights.
DSS spits these out with the message "The checked pictures are not compatible (width, height, number of colors, number of channels, only one master dark, offset and flat)."
If I check the Sharpcap CameraSettings txt file for the two (the set of dark FITS files and the single stacked FITS file) they are identical except the file for the stacked FITS has a different date/time, the number of stacked frames and the total exposure time - so no difefrence in the core FITS spec apparently - RAW, 16bit, pixels, binning
Am I breaking process and so totally irrecoverable ? (i.e. Lights must be individual FITS or pay for Pro and do darks first and include on the fly when capturing Lights)
or are there some options to set in DSS or other stackers to use ?
I have several nights and long hours of careful capture. My lights show weird hot pixel trails so I need the darks or I'm stuffed and have wasted my time - true ?
Any takers ?
I had promised myself to write this up but then NigeB beat me to it - so thanks NigeB for the prompt!
For most, the problem is how to justify the cost of a purchased system compared to a home-built system. For me it was slightly easier - I have a 2.7m dome that isnt a standard manufacturer or for which an Off the Shelf system is available. So the only approach is to build my own.
I'd previously built a timing belt dome rotation solution for the first dome I had, about 10 years ago now. This used wiper motors and glued belting and timing pulleys to drive against the belt. But havent motorised a shutter before.
The reason to do this is typically to automate the dome for unattended operation. For some systems, there is a cost in added noise of the solution using clanking chain, for example.
The dome rotation is already automated using motors and an encoder into an ASCOM driver.
The Dome layout
The dome is a 2.7m wholly fibreglass dome, the shutter is in two parts - an upper sliding section and a lower sliding section which tucks under the upper section as it moves up the dome and is pulled out as it comes down. Below right is the rear section showing the power electronics, charge controller, fuse box, remote switch, environment sensors and flat field panel. Below left is the front section, showing the two-part shutter, retaining elastic spring and below-shutter recess for controls.
The bottom of the lower section has a plunger with a mushroom head which I used for locking it using an electronic latch driven by a solenoid.
The shutter rides on PTFE glides up and down the slot sides - the glides support the shutter on the edge of the slot and preserve its spacing and alignment to the edge of the slot.
One of the key problems I wanted to address in automating this shutter was to prevent the upper shutter running away once it had crested the balance point at the top and sliding to a slamming crunch on the far side of the dome against the stops in the middle of the night.
I had tried several solutions including elastic rope used as springs to keep the two shutter parts engaged but the last solution only survived 6 months of weather.
The other problems were to minimise the intrusion into the slot gap of the drive system, to keep operating noise at a minimum, to provide manual and automatic modes in case of systems failure and to fully integrate into the observatory control system.
As I hope to show later, I have written a lot of ASCOM drivers in ASCOM ALPACA as embedded hardware devices using the ESP8266 chipset. These have native wifi built in and are quite powerful little beasts.
I also have a Node-red server with MQTT messaging, openweather api and web dashboard available for integrating. So using that as a asis for driving any solution was an obvious choice for me.
I'd spent time lo0king at pulley systems like Steppenwolf and Hugh's and chain systems like the Pulsar before coming to something I wanted to try.
The solution I devised took a lot of testing of drive systems, motors and electronics.
To minimise the visual intrusion into the slot space I adopted 1.6mm diameter steel wire rope to pull the shutter up and down, attached to a lower corner in an 'endless-rope' model.
The steel wire does the actual pulling; as it pulls the shutter up it rides over the side pulleys on the way up and back through wire guides for the returning wire.
The problem of the collapsing shutter and its changing length could be ignored since I was only interested in driving the lower edge to carry the entire load.
The wire rope needed to be carried over a few home-made rollers since it also needed to be picked up by the rollers on the way down again.
They were turned from PTFE and attached to a turned alloy block which was then body-filler glued to the slot edge at just the height to pickj up the wire while allowing the sutter to tide cleanly over.
In the picture you can see the alloy block, the nylon pulley wheel and the transiting wire guide below. There are 4 of these in total from top to bottom. The white object is one of the PTFE glides.
At the top of the run, the motor and its winch bobbin takes a few ( 5 or 6) turns for its winch action and then return the wire through wire guides back to the bottom, around an idler pulley at the bottom of the slot and back to the bottom edge of the shutter.
The drive motor itself is the ubiquitous 12v electric geared motor, effectively a wiper motor but purpose bought for the 20Nm torque requirement that I measured by experiment, trying various motors and destroying a few, to lift a 20Kg weight off the garage floor.
The drive comprises this gearmotor and a turned bobbin, acting like a ships winch on coils of wire wrapped around it. The infeed and outfeed of the wire rope is separated across the winch and displaced by 10mm or so, so by laying a few turns of wire around the bobbin, the bobbin behaves just like a sailing winch.
For this to work, the wire has to be kept under a certain tension and the wire has to play through evenly otherwise it lays over itself and jams.
You can see the bike wire tensioners from brake parts, the winch bobbin, and the large motor below. It bolts directly to the bulkhead using an alloy L bracket.
The motor started off located at the bottom of the shutter opening where it was accessible but there wasn't much space there and when I needed to get a bigger motor it would no longer fit the small cubby hole so I had to change to a top mounting for the motor, above the telescope.
Interestingly, a very small DC motor with a 500:1 gearbox on was also successfully tried but the key probem there with the torque was getting the pulley not to slip on the small gear axle. It takes more than a 4mm screw on a flat to hold that pulley .
The motor controller also went through a few iterations. While using small motors, small controllers could be used. Starting with small PWM current drivers and ending up at a 40Amp controller which could easily provide the up to 20A stall current of the final motor.
In early use, the fastening point at the lower edge of the shutter just captured the ends of the wire rope under a screw on an aluminium fixing bolted through the shutter. Thats not very kind to the rope or your fingers when the rope starts to part and presents nasty sharp wires to the fingers trying to feed it back into a small hole for fastening.
also, the rope stretches a bit after a few operations so needs re-tensioning to take the slack out, otherwise the bobbin doesn't take on the friction necessary to drive the cable without slipping.
In later use, I redid the fastening point as per the picture below - spring tensioners on both upper and lower runs, with cable tensioner for easy take up, proper wire clamps to form wire end loops nicely and small v-groove bearings to take the wire round the corners into the up and down runs.
The spring fastening points are the bolts used to mount the mushroom headed bolt used for the dome latch.
In the picture, the handle provides the inner shutter guide with the wheels which prevent the shutter blowing out and off. To the right is one of the limit switches. The wire guide goes to the slot lower surface , turns the wire around the pulley wheel underneath and comes back to the wire tensioner rig that can be seen on the lower shutter below the handle.
Industrial switches are used for the two range sensors - one represents a closed signal - ie at the bottom, the other is the fully open signal, ie when the shutter is fully at the top.
anywhere in between is also regarded as open - there will be a an inclinometer fitted as part of the controller to register its actual position to allow the shutter to be controlled to a part open position
The switches are glued on to the dome using hot melt glue. This is OK if care is taken cleaning the surface before gluing and the surface isn't in full sun. If it gets too warm, the glue fails. At some point, both of the fixings will be replaced with body filler used as adhesive.
Power is provided by a 100W flexible solar panel on the outside of the dome section the shutter runs over, so while the shutter is open the panel is not charging.
Two batteries are used to collect this power - totalling 21 Ah at 12v. A MPTT charge controller, an automotive 6A 12v regulator and a fused distribution point completes the power system.
The local devices attached to this mobile power include the shutter controller, the shutter motor, the dome environment internal sensors, the flat field light tile and two IP cameras currently under test. The last device is an ASCOM ALPACA switch device which controls 4 relays remotely over wifi to the node-red web dashboard.
The shutter controller provides a manual and automatic mode of operation. A switch flicks between the two modes. A second switch then operates the dome direction by providing the right signals to the high current driver stage. The driver can take PWM signals for soft speed control. I haven't included that yet...
In automatic mode, the controller monitors for web calls from the Dome controller and moves the shutter to the tasked position using the switches to detect travel limits.
When opening, the latch is operated automatically to release the shutter for a short period until clear of the lock. Nothing needs to be done but close to lock it in the other direction
This project has taken a lot of elapsed time but maybe a month or so of duration - ie time I actually spent on the project. Over about 4 years.
I had to work out whether the winch model would work, and what bobbin profile was required, where I could source a winch from or whether to make my own , test some motors for torque and size, turn the bracketry and wheels and finally fitted the spring tensioning system.
The system cost was relatively low.
£180 for the motor from rapid electronics
Wire rope is £5 for 10m from various stockists.
Wire rope clamps are a few pounds each.
Aluminium bracketry from the scraps box.
Pulley wheels turned from material again in the scraps box.
Wire guides bought in 5m lengths for about £15. The sort used for bicycle brake and gear wire guides.
A few bicycle brake and gear end nipples and trension adjusters from the scrap bikes bin
The ESP8266 controllers are £2 ea. I use an esp8266-01, a PCF8574 i2c 8-bit expander and a BTS7960 driver at £20 for 2 off the web.
If I replaced the driver I would use a Cytronics i2C motor controller for direct control rather than requiring bit bashed signals. These are also cheap and have 30A of current.
Risks and issues
The motor is sufficiently powerful to probably pull itself from the mountings if the batteries lasted and the shutter ran up to the hard stops for long enough. To try to prevent this It is individually fused to 10A and the regulator limits that further to 6A.
The motor in stall mode also drains the batteries very quickly. They are not really meant for this type of load. The way to manage this for me is to provide a way to remotely charge the battery at night. This so far , has taken the form of a charging coil capable of 140W through 10mm of free air from AliExpress. In the case of the batteries going flat, I can rotate the dome to align the charging coils and recharge that way. Sadly my charging coil is currently not functioning yet. I think I blew it up while testing.
As mentioned, the controller is an ESP8266-01 wifi module which is programmable using Arduino tools. Its a 3.3v device so the device bottom left in the picture is the 5 to 3v3 regulator along with another 12 to 5 regulator to manage the power drop from the supply.
The ESP is the red/blue led device with the visible wiggly wifi aerial. It is tiny.
To the middle is the i2c expander. this turns a 2-bit serial control signal into an 8-bit parallel set of signals.
One bit flashes at a 1 second interval to indicate life.
Another provides the control to the MOSFET transistor buffered through a 2N2222a NPN transistor that powers the solenoid lock.
Top right provides the switch signal inputs and the signals from the manual switches that are then fed to the motor driver unit through the 6-pin connector.
The code is available if interested at
http://www.github.com/skybadger . As mentioned it supports ALPACA, supports remote debug over telnet and remote update of the firmware.
The dome power is enabled by script (Voyager) or manually through the web dashboard. That means turning on the mount remote switch power feeds and then turning on the shutter control.
The shutter control is then turned on through the dome remote switch and integrates into the ASCOM dome controller and operated directly from voyager.
as discussed elsewhere, Voyager then opens and closes the dome based on observing conditions inputs from external sources. My external sources are the openweather api forecast for my location and my weather centre (itself a rebuild using an ESP of an old maplins weather station to wifi enable and integrate it into MQTT).
The weather and conditions get reported to an ASCOM observing conditions hub which Voyager queries for Safety events.
While all the drivers (observing conditions, safety, dome controller ) are all built and operating with Voyager, I'm in the final stages of debugging the shutter control logic for full automatic operation while all the manual switching works like a dream...
What I find most satisfying is the way the spring tensioners move in and out like pistons as the winch drives the shutter up and down. And that its a whole lot quieter than the manual process before.
I've been on these forums a couple of times for the last 2 weeks and ive found amazing advice, on telescopes, mounts and eyepiece. Besides reading countless of information on the internet about various equipments; pros and cons; and i got some queries about how to upgrade my setup.
My original purchase was a 15x70 Celestron Binoculars last year, and boy ive seen amazing things with it, specially globular clusters, Jupiter and Saturn and the Orion's Nebula; for me these were amazing; i still use them given how easy it is to look at the sky with them and how bright and full everything looks. A couple of months ago i got a 70x400mm Gskyer Telescope with an AZ mount (The cheap 99$ one that Amazon is displaying on all its adds for the last two months) it came with a 25mm and a 10mm eyepieces as well as a x3 barlows (which i didnt even count as part of my scope as it is too bad quality and i havent managed a single decent view with it).
Currently My Celestron Binoculars (x15) seem better for visualizing the sky than the 25mm eyepiece (x16) (things seem a very bit dimmer). And since the Barlow is a "no go", the 10mm (x40) eyepiece is what i really use, it has decent zoom and detailed views , it is my go to eyepiece most of the nights.
However from reading all around, ive read that most of the stuff that come with the Telescope (aside from the scope itself) are actually really bad quality, specially no name brands without even webpage, so if i were to maximise my telescope i should update some of those items.
-Recently i ordered a new Start diagonal to replace to default one (ive heard on Refractors its usually the weakest link next to eyepieces) as well as an economic x2 Barlow lens
Keep in mind i recognize my 70mm cheap telescope will not suddendly become the Hubble Telescope, and that it doesnt matter how hard i push it, in the end such a low scope will be bound to hit its limit pretty fast, thats why i avoid 70$+ eyepieces and barlows for now.
I expect to keep using this telescope for a good couple of months; at least until around August, when Jupiter and Saturn are more in the night sky, rather than morning.
Now, im very satisfied with my current telescope; while the phone mount is garbage and the phone weight and the sound of my heartbeats pretty much shake the telescope out of position, as well as how cheap the mount is; it still gets the job done for seeing interesting stuff in the sky and i have managed to do some AP for some of the globular clusters, bunch of 1-2s images (with the wrong lens), not the best, not even good pictures; but decent overall for my equipment. I am currently interested in stargazing in general and some minor AP (as i dont have a camera, currently an Iphone 7s with the mount) Buuut im interested in borrowing a camera for the low sky photos without a telescope.
I do most 97% of my Skywatching on my backyard, i live in a small country, there is some light pollution, but i can see the pleiades and the orion's nebula core on the naked eye most nights (so i guess its not that contaminated lol)
Now; currently i like finding stuff by myself and show it to the other people around me who cant be bothered to find the moon in the sky, so setting up, finding and seeing stuff is part of what i like.
With all the above in mind..... Id like to plan ahead for my next purchases.
First, im thinking a x3 barlow lens (to replace the original crappy one) and a 15mm lens (to have a bit better view than the 10mm, but less spread than the 25mm) in two or three months (with this id be able to check if my new eyepiece outperforms my default ones, but given the quality of the scope, i dont expect this to be noticeable).
And Afterwards id love to get a new Scope, but im not quite sure what i want... and i would like some advice and help in choosing my next Scope upgrade.
-I entered with and im liking the refractors; however i dont wanna spend 300-400$ on another refractor that is 20-30% better for triple the price
-Ive heard really long focal lenght might bring some distortions; and also make the scope much bulkier, annnd most importantly i know that magnification is not everything; so a 1000mm long tube would prob bring too much magnifications for me to use properly on my backyard skies. So i think id settle for a maximum of 600-700mm.
-Originally i was againts Newtonians in general, those inverted views scared me, i have a hard time of my own with my finderscope. Then i found out that Reflectors are the name of efficiency as they have more value per aperture than refractors; and as someone once mentioned "There is not really up and down in space, you will get used to it" annnd its true... save for references on the ground, like buildings, trees and mountains to help you locate where you are in the sky; once you are on it, you dont need right ups and downs.
-I did see some 90mm Orion's Refractors as well as 90-102 Celestron Astromaster Refractors (these are 350-400$)
-Im thinking a 130mm reflector is what im looking for; i think the 130mm aperture is a nice upgrade for my 70mm, and will keep me occupied for quite a long time; ive read about Orion SpaceProbe 130EQ and Celestron Astromaster 130EQ (ive also read, Power Seekers and Astromaster's are made out of pretty much garbage lol) Ive read that the main issue is the constant collimation required for them; but ive also read its something that can be learned and once you get used to it; its a pretty easy thing to do to keep getting amazing views.
-Ive also seen people recommending 6-8'' Dobsonians; i know the deal with them; if anything i could aim for a 6'' one i found a litter under 300$ ive read they are amazing values for their aperture
So, TL;DR: I have a 70x400mm Telescope, im new to stargazing, im really amazed and excited by what im seeing with my current scope, but would like an stable upgrade before the end of the year that will last me a year or two. I am interesteted both in regular and deep sky stargazing and astrophotography; im not currently interested in an motorized mount; could deal with a regular Equatorial mount. But overall i am looking for more aperture (100-150mm) to have clearer views; than focal lenght for zoom.
Im also open to the fact that at one point i might have to get a scope for stargazing and another for AP; but would like an upgrade that could help me all around for both while i get initiated.
Sorrry for the Huuuuuuuuge post, i was very excited while writing it; please let me know what you think and if there's anything else you'd want me to add to help understand my situation, thanks in advance!
This is another finished target for this season.
I (quite) recently bought a TS Photoline 102 ED with FPL53 which performs surprisingly well for a doublet. So I put it to tests and imaging, in parallel with an older FPL51 AstroProfessional 102 ED doublet.
The blue color correction is much better in the newer TS. I shoot luminance often with both and then take the highlights from the better scope.
For this image I also used some older data that I had available, shot with a 130PDS, but that maybe only made my life more difficult. Not that otherwise I shot data through the refractors in a single panel with reducers/correctors, but also in 2 panels with no reducing correctors. Same about the RGB. Some shorter exposures from the backyard, some from a dark site, most of the G data from a dark site, B and R from home (clouds came in at the dark site) and a lot of other adventures.
But in the end I managed to put them all together and made an image out of them.
You can watch it in full resolution and see other details on astrobin: Great Orion Nebula
By Mark Jo
hi, apologies if this is not correct location for this question
Trying to setup for guiding for first time with these cameras ASI385 MC and ASI290 mm mini , when both connected on usb3 and USB 2 respectively only the ASI290 appears and is duplicated. Both on USB2 appear correctly
Have looked at various forums and have checked the details below but nothing has helped with this.
Guide camera ZWO ASI290 mm mini connected by usb 2 port and ZWO ASI385 MC for imaging to USB 3 port both with new 2 meter usb cables
10 year old Toshiba laptop
No obvious issues connecting singly.
Both appear in device manager with correct name.
In Sharpcap when both are connected ASI385 to usb3 and ASI to USB 2, the ASI290 appears duplicated and no 385.
Both connected to USB 2 ports they appear correctly under the ZWO cameras.
Have looked in some forums and have most recent version of sharpcap installed, updated ZWO drivers, disabled USB Selective suspend in the power management and disabled the sleep option in windows.
Checked the USB drivers and they appear to be upto date
When both cameras were connected the ASI 290 was losing connection every 20 – 30 seconds, disabling USB Selective suspend being disabled appears to have stopped this happening
Is it that the laptop needs to be retired at least from astroimaging I saw a mention that there could be an issue with chipset, or is there anything else that I can do ?