FrenchyArnaud

EDIT -[    Airing tonight 23/05, BBC1 7pm, the One Show  ]

I cannot not share this with the community because you guys can appreciate...

The BBC spent the whole day with me yesterday at home filming about my Pier of Doom. I REALLY tried to explain to them that most of you do much better pictures than me but somehow they did not buy it. 

Massive case of Imposter Syndrom here but that was pretty fun. 

That will be a short inconsequential segment of a few minutes but still pretty cool and a good ego boost. Date of broadcast still unknown 🙂

When I build my DIY EAF I came accross the same issue.

The problem is that the metal core inside the plastic fine focus knob is dislodged and the plastic outer case of the knob just slides freely around the core. When you turn this knob, due to friction the plastic turns around the core without moving it, when you turn the coarse knob, core and casing both turn in sync because no force is applied between them.

You need to pull the casing out cautiously, unscrew the tiny allen screw to free the core, then when you have both parts in your hand, a drop of superglue on inside the edge of the plastic then push the metal core back in (making SURE the screw thread and the opening in the knob casing are aligned!) 

22 minutes ago, LuckieEddie said:

Onstep could be your friend for this project. Its a full featured open source control system that runs on various Arduino systems. Drivers for Ascom and Indi are mature. I've converted two mounts to use it so far an E-Q5 and a G11.

Another good pointer, thanks! 

1 hour ago, Dr_Ju_ju said:

I don't know whether you've come across this site (https://www.astroeq.co.uk/tutorials.php) but I made one to drive an old EQ5 mount, & it works quite well ....

Thanls, a few interesting pointers there 👍

Hi guys, 
Starting yet a new thread for another diy build - but this time it could well be the diy project of a life time because, let's face it, I am too stupid and arrogant to know when I am out of my league. So, on the strength of "He did not know it was impossible so he did it",  I am tackling the build from scratch of an equatorial mount with very serious ambitions, namely and in no particular order: 

- Must be able to take overkill loads without breaking a sweat, even if one day I can afford a quattro 12" or sthg like that. 
- Must have near perfect tracking speed
- Must have negligeable backlash RA + Dec 
- Must be 100% ascom compatible so as to snuggle lovingly with NINA & PHD2, which also means
- that it must be "pulse guiding capable"

The things I DO NOT need, because it will be on the pier with illimited power supply:

- A weight limit. Even if it ends up weighting 50kg: who cares. 
- Battery autonomy and reasonnable current use (it's on the mains)
- Advanced Goto.  I only need to be able to point roughly in the right direction, NINA will plate solve afterwards. 

With this in mind I have already determined quite a few things. 

Hardware: 
- Motors will be heavy duty steppers, NEMA17 or even 23. With low backlash gearboxes either 30:1 or 100:1 and the transmission will be 100% belts.  First calculations tell me that can move up to 15kg of balance error which means it's effectively unlimited load. 
- The base will be a wedge, much easier to build rock solid than a GEM turret. 
- For now the plan is to have both axis free spining using car wheel bearings (there is pretty much zero play in these things and the load is obviously not a problem) 
- These axis will be hard mounted on a BIG steel barcket that will in effect act as the "chassis" of the mount.
- It will embark its own RealTimeClock and Eprom so that it is effectively plug and play.

Electronics: 
- prototyping and firmware/software dev is now on Arduino Nano and Uno but I will surely need a Mega plus a whole collection of rotary encoders, LCD, temp probes etc. 

For now I have just put 2 tiny steppers on a bread board to confirm that I can get it to be seen as a telescope by a basic ascom driver and get the motors to act as Ra+Dec. So yes, this tiny mess is, technically, a computerized telescope mount.

First estimations tell that the build budget would be surprisingly low - in the order of £200 to £500 at the very, very max. In the other hand, the firmware and ascom driver could be really, really long to write. 

But hey, dream big. 

All ideas, inputs, remarks etc more than welcome. 

2 minutes ago, Paul M said:

Thank you, can I start by thanking my parents...🏆

I'm glad you like it. The very latest version ( might be a beta) has the simbad annotation feature.

If I remember correctly, press right (might be left!) mouse button somewhere over the area of interest of your image and drag out a box. Then another mouse click gives a drop down menu, somewhere in there are the online query and annotation  options.

That thing goes crazy!

Yeps and as a bonus you can export the image in full def, annotated, which is a very cool feature. I have found the functions to send directly the request for sthg on the picture to be ID'd and detailed via NED, which is also an amazing thing, basically "point and open the database on the relevant entry" - hours of fun right there for rain rainy days ! 

9 hours ago, Paul M said:

A good tool for identifying seriously faint objects in your images is ASTAP. A multifunction program that has 3 levels of deep sky annotation, a "normal" bright object option, hyperleda, which goes deep and a recent addition with which you can select a region of your image and click on Simbad Annotation and a whole universe of stuff is identified in your image.

And the award for best advise of the year goes to @Paul M !!! 
This little plugin for ASTAP is just absolutely fabulous 🤪 And I cannot believe how fast it is; ASTAP was always really, really fast but Hyperleda is pretty much instantaneous. Never heard of it before; but I will never forget about it either! 

Ok, it's late March so it's about 1/4 of an award but still, spot on. Thanks Paul! 

8 hours ago, SamAndrew said:

I believe that is PGC49919; NGC 5471 is part of M101, on the other side towards NGC 5477.

I might have mismatched my orientations... Looking into it, thanks for the pointer

26 minutes ago, ollypenrice said:

If you've shot the Leo Triplet you'll have collected a good number of quasars near the Hamburger galaxy. These are seriously distant.

I have not... yet. I explored on stellarium and apparently the Markarian's Chain has quite a few really distant things with structure too... I might give both a go. 

13 minutes ago, Paul M said:

A good tool for identifying seriously faint objects in your images is ASTAP.

Excellent point, I have it installed (it's my NINA plate solver) and I use it for stacking too, I never even thought of using it as a stand alone plate solver, trying tonight!👍

Hi guys, I was exploring the background of my recent images as it's a personal mania of mine to try and identify the furthest object I have pictured. (Currently, on this same image: NGC5422, 100 million LY) I found this smudge that is not even ID'd by telescopius - turns out it it is NGC 5471 - HII Ionized region. I scoured the internet and all databases I could find, no way to find the distance to that thing. Does anyone have the info? (and if so, I'd love to have access to the source of the info too!)

52 minutes ago, Bruce Leeroy said:

Well done on making the Daily Mail 👍

You meant Daily Express didn't you? I don't think the Daily Mail published If thry did, I need to know 🤭

12 minutes ago, Bruce Leeroy said:

Well done on making the Daily Mail 👍

And the Mirror 😁

4 hours ago, powerlord said:

do be aware though that those wee 28bys do not have a whole lot of torque to them

Hey  Actually, the focuser has been built, installed and thoroughly tested - it works absolutely perfectly. The thread is here: 

I had some doubts with the torque as this is something that always comes back in these discussions. However, this is only true with direct assembly. In my case, I had installed a belt and pulley which gave 2.5:1 gear ratio but on tests this gave me a too short course - so I changed the pulley for a 36 teeth that has the same diameter than the 10:1 knob,  and in this config, the motor has no problem pushing/pulling the camera in any orientation, including with the cooling box installed (dslr+cooling box = 1180g) , including with the focuser straight down, the motor having to lift the full weight with no mechanical avantage. In fact, I tried to stop the motor with my fingers and yes, I can, but the force to apply is VASTLY superior to the force I ever need to apply to move the focuser. 

I imagine that if you have a massive camera at 1000g+ AND the focuser is a bit stiff/tight, the motor might jump steps. If that eventually happens I too will have to stepup but after about 20hours of sessions and about 50 AF cycles it gave zero signs of weakness. I am building a second one for my C8N that I am converting into photographic; the focuser is of very, very poor build compared to the 130PDS and the knobs, though much bigger and giving a 4.75:1 gear ratio, do not have the secondary 10:1 knob. So it is very possible that with the extra friction, and having 4.75:1 instead of 10:1, the motor will prove out of its league. Well, I will shove a nema17 on the thing if needed   Also, I will put a rotary encoder on the other knob to monitor in real time if there are any issues with rpm or skipped steps. 

 

20 minutes ago, malc-c said:

 So all you do is drive the LED in the OPTO device to activate the relay coil, which could be supplied by its own 9v or 12v depending on the voltage rating of the relays.

Yes, exactly. From the arduino perspective, it's only turning leds on or off, totally oblivious to the relays themselves (these happen to be rated for 5V)  This specific relay board has a native LOW logic though. Of course, there is always the possibility of connecting "normally on" rather than "normally off" but in some cases I might need to be able to turn the mount itself on without the laptop connected to it to command the relay HIGH (coil off, therefore circuit closed therefore mount powered)

It follows that it is just simpler and safer to have the arduino ungrounded, to keep the total isolation and the LOW logic with Normally Off electric connexions. And I know what you think at that point: "lazy idiot, what prevents you from having some coils Normally On and others Normally Off?"  Well, the answer is NOTHING 🤪 but I just did not see any downside to energising the coils separately and coding to initiate HIGH or LOW depending on the gear   Besides, I know the risk of failure is low, especially with 12V 2A grounded in the relay while they are rated for 2500W, but it occured to me, should there be a failure, I prefer to increase the chances that the coils fail open rather than closed for obvious reasons. So... yes, that's why the jumper went off and the relay board is not grounded to the UNO. 

Also, remember - my first failure was due to too low current in the USB relay. I did the whole thing especially to be able to drive the coils on their own power, so psychologically, powering through the 5v pin was no satisfying. I might have over-engineered the thing a bit... But in that case I don't see a downside. 🤭

14 minutes ago, malc-c said:

Any reason why the GND of the relay board inputs is not connected with the GND on the Arduino, especially as it looks like the board has opto isolation to keep the control side of things isolated from the switching side

That's actually precisely the reason : if the GND of the relay board is connected to the arduino, you lose the benefit of the octo. It becomes conceivable that in case of catastrophic failure of a relay, this GND becomes live, fries the board and even the laptop on the other side (the relays are good for up to 10A)

With the jumper removed , the coils are energized through a the VCC-JD and the arduino uses the IN pins to sink the current as grounds. Which is why the board is low-triggered (LOW pin means active coil here) and the only connexion between the arduino and the coils is the light of the LED in the octo - it becomes physically impossible for the current to leak anywhere. Connecting the GND arduino anywhere would defeat the purpose of octo isolation... Only the tiny 5v PSU grounds there. Even if it failed, there is no way it can damage anything - at worse, the UNO would fry but the gear on one side and the laptop on the other side are absolutely safe. 

EDIT - That's also the reason why the relays are interrupting the negative of the different elements : so that the relay board cannot, ever, become live, it's absolutely impossible. 

A quick video of the actual box completed. The red wires are the 12V input that powers the coils via a tiny 12v>5V transformer, the arduino is powered by the USB and the two circuits are totally distinct with no possibility of electrical leak. The 4 cables are 4 junctions from the relays, meant to interrupt the ground of the gear, and of course the USB is supposed to be connected to the laptop via the hub on the pier. 

The box is 100% sealed with hot glue and I am confident it can take a storm without letting a drop of water in. 

Hi guys! 
Since I built the pier I am going full on with total automation 🤪

My main problem was that my camera, a modded canon 450D,  randomly "hangs" in NINA. (not when used standalone) It will say "downloading...." forever but is in fact stuck. It will not disconnect or reboot, I need to physically pull the cable. Not a big deal, two or three times a night I need to pull the USB cable that supplies the power to the dummy battery - and we are back in business. 

Except that it means staying up and monitoring the connexions... Staying awake is not a problem but being at the computer just waiting and looking at the guiding graph - that's dull. 

So I thought, why not put a relay on the power supply of the camera? There are relays that are powered by usb and can therefore be piloted directly from the computer, which means, with the remote desktop aps, from anywhere - INCLUDING MY BED!

I tried but because of the length of the USB (10m) the relay will trigger to the data input but the coil would not physically activate. Disappointing. 

Long story short.... I ended up DIYing a completely remote system to bypass all the switches, based on an arduino board and a 4channel relay board. I have created my owm firmware taylor made to my needs and while I was at it, a nice little desktop app that both monitors the state of the relays and allows me to start, stop, or reboot any of the piece of gear, one by one or all at once. Thanks to Google Remote Desktop app, I can also command that (and Nina) from any of my computers or phone and from anywhere in the world. The only thing that is not automated now is the removal of the BBQ cover from the pier!

One channel turns the telescope mount on/off, one turns the dslr on/off, one turns the dew heater of the guidescop on/off - one relay is still free. 

The total cost is : arduino UNO, £18 for 3 = £6, a 12v>5V2A converter, £2.5, and the relay board £4.  If someone is interested, I can supply the exact list of parts, schematics, firmware and desktop app. Demo in the video. Prerequisite : Python3, a remote desktop app of some sort, an the arduino IDE (free and easy to use)  

EDIT : the video does not play on my PC from this page but it does on my phone. Not sure what's up with that. 

38 minutes ago, DaveS said:

Then I thought to check the reducer (Which is sunk into the focuser)

Rooooo! That's a good one! 🤣😂😝🤪

2 minutes ago, tomato said:

There is now over current protection on the motor.☺️

The very definition of "learning the hard way" Something has to give, the dome, the rail or the motor but it will not be the padlock for sure! 

To conclude this thread once and for all, allow me to share the first images taken from the pier, with the DIY autofocuser running and the L-pro actually installed on the comma corrector (don't ask) 
My processing skills have not caught up yet but the overall improvement in the subs is absolutely enormous, with 90%+ keepers compared to my usual 50% on a good day and my stars are both much rounder and much tighter. Overall, there is no question that it was all well worth it! 

3 hours ago, 900SL said:

left the Bahtinov mask on for the last two hours

I FEEL FOR YOU 🤣🤣🤣 You have no idea how many times I did it. Like, I don't ever learn 🤭

First try yesterday... And there is no question that ensuring critical focus on every single sub frame makes a massive difference on the final result. I cannot in fact, believe how much of a difference it makes, it's like massively upgrading the optics. This is officially my best galaxy picture so far, and by quite a mile - the Pinwheel M101, 51x 300s + 25D+25F+25DF.

I am overwhelmed by how well this intimidating project went and by how much it actually improved the final result. I can even see 10 or 12 very, very distant galaxies in the background, by my modest standards that is an image that I am really chuffed with and that I never could have done without computer-assisted focusing.  The combination of the permanent pier+EAF is a proper revolution to my imaging process, I have no words to say how pleased I am! 

So my monstrosity is done! Surprisingly, manufacturing the bracket was the most tricky part. I needed quite a few attempts and fidling to achieve the proper belt tension (not too tight, that would block, not too loose, that would slip) 

But! Incredibly it worked perfectly on the very first attempt tonight. I just can't believe it.  The very first run gave me an unbalanced but nice curve,

the second run was as good as I could expect with apparently very, very little backlash.

When I took the 30s test image after the 2nd run, my stars were pin sharp, better than I was ever able to do by eye and much, much faster. 

Pun intended - over the moon. 

Opening this thread for a laugh because I facepalmed this morning. You know, this second of realisation when you are overwhelmed by the sudden evidence "I am an absolute cretin" - facepalm. Share yours! Here is mine : 

Since I build the pier, I have had only 1 clear night to do proper full tests, a full session imaging.  I spent a little time on M101 and as you can see, the colour balance is not quite right, shifted to red. 

That is because I have been battling with a severe light pollution gradient despite a high altitude target and an expensive Optolong L-pro. 
Bit disappointed by this L-pro. It is clearly no match for the city lights. 
As I am building an autofocuser I had to take the OTA off the pier, and I took the camera off the focuser.  Then and only then I realized I forgot to put the filter on. It is still in its box. 

I will leave a scaving review "L-pro optolong, don't buy it, it works ONLY if you take it out of the box AND use it, zero stars." 
F.A.C.E.P.A.L.M. 
I should not be left unsupervised.  🤦‍♂️
 

The autofocuser is on its way! That will be a massive upgrade

Hi guys, so, following the thread here : 

I decided to undertake the build of a DIY electronique focuser. I could of course, buy a zwo eaf or equivallent but that's just too expensive (no offense to @FLO )
DISCLAIMER : I know NOTHING about electronics. I know quite a little bit about programing C and other languages - but as it turns out, contrary to my intuitition, there is absolutely no need to. 

So, after a lot of reading and studying, I settle on an arduino based system and specifically, "myFocuserPro2", a very complete project that you can find here. 

I bought all the parts off of amazon and ebay. That's a little elegoo kit with cables and breadboard (£12), and arduino UNO Rev3 (£10), a stepper motor + associated driver board (28BYJ-48 & ULN2003, £6) and a Step-Down Power Supply Converter Module 12V to 5V (£3). It was not needed but just for fun I also bought another Arduino, a nano (for the permanent assembly when my prototype is ready to deploy) 

The total is therefore about £30, and I will need a few mechanical bits and bolts for the linkage - it will all be well below £50. 

Having never done any sort of electronic assembly, and having read an awful lot about the topic, I was expecting a very tedious and complex process. In actual fact, it took me about one hour, download of software included, to get a working prototype that is 100% integrated to NINA. 

I must point out at this stage that I am in fact building the most basic version of myFocuserPro2, with no probe, display, buttons - nothing. My plan is to have everything piloted from the computer and the linkage will be pulley and belt. So, I just stupidly copied the connexions explained (no need to understand what does what, just imitate the plans supplied) and upload the firmware (so easy it's stupid and no need to even look at the content, let alone edit the code), then copy-paste the libraries were they belong (it is essential but dead easy and very well documented) and download the ascom driver (supplied too, nothing to think about, just grab and install.) Anyways, after less than an hour, without knowing anything and for pocket money, I have my autofocuser 100% integrated to NINA ! 

So, the rest of the project will be to

1) replace the arduino UNO by the nano and confirm it all works as intended
2) encase the electronics and lengthen the connexion between circuit board and motor
3) Link mechanically the motor to the focuser of the 130PDS (which involves building a metal bracket and installing a GT2 pulley and belt)

Pretty chuffed with how that started; I can already say that if you are wondering how hard it is, just stop and go for it, the 115pages of tech of the pdf file are there just to frighten you, it is so easy to do that it is almost insulting. The devs of that project did an incredible job at pre-digesting everything for us.