John78

On 14/05/2021 at 06:53, astrosathya said:

looks like if i need to use my 8729 drivers i need to wire up M0 and M2 on the CNCV3? or am i getting it wrong?

Never used 8729, but this guy has a build log of exactly what you are using...

ONSTEP EQ5 GOTO (groups.io)

Your gear ratios will be different, the AstroEQ site has all the appropriate gear ratios for the SW mounts.

On 11/05/2021 at 18:31, skybadger said:

I think you are asking a lot from those steppers to drive much at 1/32 step or more.  I ran mine at 24v for a while to see if they could get past the base stiction and get up to to speedbut you can of course start coarse and go fine later by simple reprogramming. 

 

The trinamic drivers in either drive mode stealthchop (silent) or spreadcycle deliver more torque than a conventional driver in half step mode, and spreadcycle 256usteps delivers only slightly less torque than full stepping, they're amazing pieces of tech, the issue used to be generating the clocks to accelerate and run them at high rpm in 256usteps, but with modern processors that's not an issue, no way could an arduino do it.

Thanks to OP and repliers for highlighting onstep - have ordered some MaxSTM boards from JLCPCB today to change from astroeq (which has a really frustrating windows bug) to an OnStep controller.  The ascom info required seems to all on this site.

edit: let me rephrase that, windows has a really frustrating bug, that requires the astroeq to be powered before you plug in the usb - it works fine in linux as it handles the ports properly.

http://www.stellarjourney.com/index.php?r=site/software_telescope

Yeah one of the reasons I'm attempting to move from Windows to a Rpi is EKOS keeps my QSI583 connected properly 100% of the time, sometimes windows/ascom totally loses the plot - I cannot control the camera, but the filter wheel still work fine through the same USB port, which forces me to reboot and then I lose the pointing model, guiding cals, tracking etc....  So understand mitigating software frustrations.

One thing I've never tried is the autofocus using bahtinov option, the HFR options I use are a bit slow I need to do the average of 3 subs at 5 to 7 focus points for it to reliably find best focus - it looks like I could test that tonight as its too moony for real imaging.  I presume it models the diffraction lines and moves them to dead centre.

On 10/04/2021 at 13:42, AMcD said:

I mount my electronics on a home made plate mounted on top of the scope rings.  It is getting a little crowded now and I am in the process of designing and building a remotely controlled Bahtinov mask and scope cover.  The electronics box for that and the stepper motors will have to hang off the side like the current TEC box for my QHY8 😁

I'll bite, why do you need a remote bhat, if you already have a remote/motorised focuser?  The autofocus routines via various free software is amazingly good these days - I was considering an automatic flat/scope cover, but its not entirely clear how to implement it on the front of a refractor without it being a wind sock or having 270 degrees of  motion.

Fractory do some decent pricing on laser cutting.

On 09/02/2021 at 16:55, Stub Mandrel said:

The S/W coma corrector is designed to give the correct performance when the flange (i.e. the flat surface at the bottom of the 48mm is exactly 55mm from the sensor.  This works well with custom M48 to Nikon/Canon fit adaptors.

What you probably need is to discard the T-mount nosepiece which is too long to use and instead use suitable adaptors between the CC and the body of the camera.

QSI can probably tell you what to use.

This is how I use mine with ZWO kit: M48 - M42 adaptor, followed by various combinations of various M42 spacing rings and my filter wheel to make up a about 50mm, leaving about 6mm for the camera backfocus. The extra length allows for shortening of the light path by 1mm due to refraction in the filter wheel.

 

 

 

Indeed - what I need is a M48 faceplate for the camera - which QSI don't appear to make, the SX one looks like it would be able to fit if you make a small adapter plate - or I could machine a whole new one - although cutting the thread might be a challenge and then I'd need to find someone to anodise it.

Is anyone using a QSI 683wsg camera with a Skywatcher coma corrector - I have one on the way (camera) and I forsee back-focus issues,  The Skywatcher CC has M48 threads, if I use the M48->T2 M42 adapter to screw on the end of the CC to then screw into the camera I effectively add 7.3mm to the total distance because I cannot screw the adapter down to be flush with the flange.

So the question is - is the 55mm measured from the flange, or the very back of the threads on the CC, there appears to be no optical drawing I can find for the CC?

The camera with T2 adapter has a backfocus distance of 1.98", so i'll be out at 57.6mm before including filters etc...  I suspect the solution is a custom M48 adapter plate close to the correct thickness to screw the CC straight into, that or turn 3mm+ off the end of the CC in the lathe 🥶

53 minutes ago, Honcho41 said:

That's the one I bought.  It's a USB camera.

I don't necessarily think that's a problem the code appears to support any cameras your RPi works with - it just needs different configuration options.

https://github.com/CroatianMeteorNetwork/RMS#capture

Note the most recommended camera is analog and uses a USB analog to digital dongle to interface to the RPi.

Dont they have these in stock on amazon uk?

https://www.amazon.co.uk/ELP-Webcam-USB3-0-Camera-Webcamera/dp/B07KMW5TRS

55 minutes ago, alacant said:

Really? Maybe you missed focus a bit? Faulty examples? Dunno... 

Granted, with their tiny apertures, they are very (read: painfully!) slow, but if you've a few hours (read: the whole night!) to spare, we find that they really are capable of fine results. This is an example of an area in Auriga taken with a €50 Super Takumar 200/4, and this is the same region with the even cheaper Takumar 135/3.5.

No need to remove the lens pins; choose the adapter without the flange.

Cheers and HTH.

Well, like I said my experience with my first 200mm was so poor I bought another and that was, if anything, worse.  I even built an ollypenrice type micro-focuser basically a 3D printed lever clamped around the focuser barrel which was some 150mm long with an M3 rod and a thumbwheel, then subsequently a fully motorised micro-focuser using HFR focusing.

Your images look like they are stopped down, these lenses aren't slow compared to telescopes - they're quite fast esp the 135mm F2.5 is in the very fast range, I will concede I found them to be somewhat better performing stopped down using a step down filter adapter (I find the aperture blades detract from the images) - but then its slow, which defeats the point, and in all honesty still nowhere near as good as the benchmark lens for this type of imaging: the Samyang 135mm F2, its flat across the field, fast and free from aberrations even wide open.

There are many more threads across the internet in general with people with performance problems with these lenses than success', and once I'd failed to see a noticeable performance improvement using a halpha filter I gave up and these lenses wont see the light of night again for imaging.

Unfortunately in my experience (2x200mm F4, 1x135mm F2.5) these SMC lenses are just no good for astro - even though some people appear to get good results with them.

To reach proper focus you need to do the 3 screw trick, you need the thin version of M42 adapter, you need to remove the pin on the lens that pushes against the adapter.

Once you get to proper focus, without tilt in my experience; you get the most heinous star bloat - even with a Halpha filter in the image train its just provides totally unusable data using a Canon EOS body astro modded or my cooled mono CCD.

This popped up in my YT feed a few days ago...  Its quite interesting for 3D printing things in general but especially stuff that goes outside on cold damp days.

I haven't tried it yet, still getting my new printer running right before I switch over to PETG - but it seems like a good way to make strong brackets without making them super thick and also waterproof electronics boxes, all sky cameras etc....

I realise on consideration the other (probably better) method, is using PCB printing paper and adhering the toner to glass...

https://coolcomponents.co.uk/products/pcb-toner-transfer-paper?variant=45222872270&utm_medium=cpc&utm_source=google&utm_campaign=Google Shopping&gclid=CjwKCAjwlID8BRAFEiwAnUoK1eHj7KnvNASDiU4w20kUj6n_DuhFZLxh3x6JABt7iNEtvxpcVAhPYBoC1goQAvD_BwE

Any 600 dpi laser printer should be fine, even a bog standard £40 special can print a toner transfer for even the most ridiculously small legged chips.

This place appears to have them in stock at sensible prices and despite the 1998 looking website it does have a COVID19 notice up so would appear to be in buisness still

http://www.awrtech.co.uk/awr_cat.htm

600dpi is 42um dots, so if you aim to print the lines in the 600dpi direction, perpendicular to the way the paper feeds, and print screens in 42, 84, 126, 168um lines you should get a usable result.

The way 2400dpi is achieved wont work for printing 10.5um lines, its not really 2400dpi.

NINA is absolutely brilliant, its more than just an AP control app, its like an AP control OS although it uses all the tools you know and love under the hood it pulls them all together in one window in one umbrella in a logical fashion - for free, and as pointed out the autofocusing routines in particular are spot on and more featured than in any other tool I've used. 

In my opinion its totally left SGP in the dust, even without knowing its going to subs business model.

The other nice thing it does is uses the astrometry API to solve your images if plate-solving fails, takes a few minutes while it gets solved but it works every time.

ASTAP however as mentioned in this thread, is potentially even more brilliant than NINA, I don't know how it does what it does - but it plate solves anything, pointing anywhere, blindly, largely out of focus, in a fraction of a second.  The amount of hair I've lost and imaging time to boot because ASPS or Astrotortilla decide they're going to take minutes to solve or just refuse to solve at all and require masses of debugging only to end up back with the settings you had in the first place, its like they're afraid of the dark - they always work nicely during the day!

ASTAP also has analysis built in to show you issues with your image train like tilt.

These two programs are really exciting for the world of AP.

On 24/09/2020 at 08:10, Spaced Out said:

There are a number of ‘firsts’ for me here.

Got my first ever image with the new V-power focuser on my 130PDS, it’s my first step into imaging with a dedicated mono camera (ZWO ASI 1600) and it’s also my first ever use of any calibration frames. It has been a steep learning curve and lots could have gone wrong, however, I am just happy to have produced this colour image !

The processing isn't great, I still have much to learn and I’ve found it quite difficult tbh. I have struggled with star bloating when stretching, wasted hours trying to produce star masks (but just produced ugly  halos), then wrestled with colour balance and battled some nasty noise as I tried to stretch the image to bring out the dark dust clouds (I’m guessing I need more data to smooth things out ?).

Anyway, this is the result so far. I will have another night on this target soon hopefully and see if adding more data helps improve things a bit.

 

Thats a brilliant image!  For star masks - try starnet++, easy, free, accurate starless images and mask.

Having owned both (well, I still own a 130PDS), the 130PDS is much faster, if you use a SW 0.9x CC much much faster - F4.5 vs F6.37! 😮

The 80ED weighs 4.1kg with tube rings vs 4kg for a 130PDS.

They are both excellent scopes, the 130P-DS is phenomenal value but trickier to use to begin with, and its trickier to balance on the mount as all the mass is at the focuser end the mirror doesn't provide anywhere near enough counterbalance.

So the real differentiators are the price and the great divider of astrophotographers - do you like diffraction spikes or not?

Although this is not UK its Germany I've heard some good reviews from his service.

http://www.stathis-firstlight.de/spiegelschleifen/materialeng.htm

Its M51x0.75, but you'll need to adjust up and down in OD until you get a nice fit as FDM type printers are pretty variable in terms of printed dimensions vs cad dimensions, and you need to print at 0.1mm layers or less, it also helps not having complete 360 threads.

I'm fairly experienced with astroeq - I've done a DIY mega2650 one using drv8825, tom's board/ic's using tmc drivers and I looked at the new version with surface mount just as a project.

So I can probably answer your questions if you post them.

After somewhat of a hiatus - I appear to be imminently back in the game (soon as dark come back anyway!), I chanced upon a 428EX mono for an unbelievable price so I snapped it up.

So I'm considering a 135mm F2 for the FOV, speed and price for predominately narrowband imaging when paired with the 428, the concern is the under sampling - I would assume for best results I'd ideally want a scope in the 400-600mm range?  The issue with the longer focal range is the size of the Ha targets!

Anyone have any thoughts on the subject?

So the technique we got taught when we were boys at school involved a coke can, biro, needle and wet and dry paper.

Cut a section of coke can out, push it flat

Push the biro into the can to form a small depression

Went and dry the hill down until its thin

Push through the needle as shallow as you can, if you cant get the needle through - wet and dry some more.

Here's the work in progress cube and the remnants of its Chinese laser cut printer that died so the cube may live... 

I'm missing some 10mm carbon fibre tube and a new hotend to get it printing. 

Another point I think is worth making - is for me my printer is an enabler for my other hobbies, I want to press print and to get what I want first time not continuous upgrades and fettling.  For quite a lot of people their printers are their hobbies.

I would buy a turnkey printer, almost surely a Prusa mk3 - but I don't have that sort of money burning a hole in my pocket.