SiD the Turtle

Just to add if anyone finds this post in future, a few points on the guide at High Point Scientific:

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If you have any equipment that requires 12V DC power that you want to run off the ASIAIR’s DC out ports, connect these cables next.
Note: These are not intended to run a mount. Connect your mount to a dedicated power supply or separate power port if your supply/ battery supports this.

...

The longer version is this - the per channel current limit for the ASIAIR is too low for most all the popular 25 lbs and up payload capacity EQ mounts. Additionally you can’t get more power out of the device than you put in, which is an easy calculation in this case since the input and output voltage of the ASIAIR is the same - so we can just look at the Amperage. A popular ultra-portable EQ mount needs 2A, which means that if you add a cooled camera at 3A you’ve now maxed out the 5A power supply with nothing left over for the ASIAIR (or any USB devices connected). Now if you were going to run just an ultra-portable mount and then use the ASIAIR with a DLSR, you could be within the limits of the ASIAIR’s output.

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ZWO has also stated that if you are connecting a power supply that is capable of more than 6A of current, that a 5A fuse should be placed between the supply and the ASIAIR - ergo there is no benefit to purchasing/ using a more powerful supply, only more complication.

Thanks again @Elp, @Carbon Brush, this is why I love the astro community, you learn so much and people are happy to share their own knowledge. This is the stuff that's not in the manual!

So electrics are not my speciality so happy to be wrong here, but I guess the concern is if there's any chance you could draw more than the system allows. Take the Celestrons: you pull more than 3A, they shut down for safety. The ASiair can take in 5A max, what if the downstream components ask for 6A and your PSU can provide 6A? Does it cut off, does it try to deliver 6A? Does it cook something on the board? I know the Pegasus Powerboxes are built to be fairly idiotproof to prevent burning out devices or the powerbox itself. Is there a risk here that the Air doesn't?

Oooh good shout. I don't know how good the regulation is on the Air, but I don't want to cook it.

Thanks @Elp, @Carbon Brush. Indeed if I turn off the dew heater the draw appears to max at about 2.1A when slewing. I guess I could turn off the dew heater, GOTO, do all the usual setting up of tracking etc, then turn on the heater. But as if you suggest, the draw is still high on the dew heater, I might be dancing a little close to the edge. Still, gives me options regardless.

Interesting how even the mains link might cause me an issue if it breaches 5A. I have a relatively cheap Lynx Astro 12v adaptor that delivers 5A that I'm using indoors for testing. I have a ludicrously expensive Pegasus Astro adaptor in a dribox in the garden, and now I know why it was so expensive: it can support 10A. Probably more expensive than it needed to be, but it's been as solid as a rock for years.

Thanks @Carbon Brush that's good to note and tracks with my findings. You go over 3A, it just turns itself off instantly.

Thanks all, I can't believe how daft I've been. @ONIKKINEN is correct, that's my old tank, and my new one is its baby brother. Both are rated at THREE amps, not FIVE, only the even larger version will do five. I'm simply underpowered, nothing more nefarious.

When the whole system is going (tracking, one dew heater, camera capturing with cooler running, anti-dew on the camera on, guide camera on) it's using about 2.5A. When using GOTO, it peaks at about 4.5A, way above what the batteries can do. Even if I turn down the slew speed it seems to take the same amperage, so no luck there. I guess this matches the AM3 documentation, which states it needs 1.7A during GOTO.

I put together this setup as a travel scope, and by travel I mean small enough and light enough to go in airline carry-on, so a car battery or proper caravan-spec lithium battery is out of the question. However, all is not lost, as @ONIKKINEN suggested, I'm going to run the mount off the smaller battery directly, everything else off the larger one via the ASiair and spread the load. Plus smaller batteries are easier to spread across backpacks for the aforementioned travel, rather than returning this battery and scaling up to a monster one.

9 hours ago, Elp said:

I assume you're running the power to either the air and feed the mount from that or the other way around (does the am3 have 12v out capability?).

For reference, the AM3 does not have the separate 12v out option.

I've got a brand new ASIair Plus, a ZWO AM3 mount hosting a Redcat 51 and a ZWO ASI2600MC-Duo camera. This is all working lovely when connected to the wall via a 12v power supply, but I'm having issues with Powertanks.

I have an old Celestron Powertank Lithium Pro which has seen a lot of abuse. When slewing, the power entirely cuts out and the battery dies. So I bought a brand new smaller version, the Powertank Lithium, but it has similar issues. Basically on slewing after a moment I hear a relay-like click in the mount, the same noise you hear when you first power it up. Then it decides it's only going to slew on one axis, and beeps if you try the other.

In the ASiair app it seems to occur when I breach 3 amps, but that's miles under what either battery is rated for. So, I think the ASiair and the mount are fine, as they'll work off of the wall socket. On battery if I turn off everything apart from the mount, it slews fine, so I think it's load. I'm going to try it on my HEQ5 mount via a Pegasus Powerbox to be sure, but anyone else had similar issues? How best to diagnose the cause? Are these batteries just rubbish, or am I missing something?

22 hours ago, Grant said:

I built the app and I’ve been on holiday this week so haven’t been able to respond.

Android have made some changes which mean in essence we have to rebuild the app entirely if we want to support the latest versions of Android and given the app is just a wrapper for the website we are instead moving to a progressive web app model which will work on all platforms and make future updates much quicker to deploy.

I expect a beta version of this to be available in late-April / early-May.

Hi Grant, thanks for the news, sorry that the latest version of Android is a pain!

With all respect to @FLO for providing the Android app free of charge, the lack of response here and to my emails is disappointing.

Retailer and William Optics both told me to simply screw it back in until there was resistance, but not overtighten. I did want to ask WO exactly what it's for after a slightly vague answer, but with the earthquake since, I'm not going to pester them.

The focuser seems fine, but as we have this infinity cloud over the UK right now, not had a chance for first light yet.

The android app works a little better in app than the mobile website.

Yeah if you read the reviews, you'll see lots of complaints. I'm no expert but I wonder if it's something silly like each time a new Android version comes out, the developer has to go and tick a box to say it's compatible (or fix any compatibility issues). I'm sure if I sourced the APK I could sideload it, but wondering if there's could be an official update.

@FLO any news on support for Android 14?

Thanks all. Seeing as it's brand new and very expensive, I've decided not to mess with it until the retailer responds!

Will post back here when I know more.

As the title really, lovely new Redcat 51 with the new WIFD focuser arrived today, on getting it out of the box there was a grub screw loose in the package. Upon checking, it's one of these circled in purple:

The focuser seems fine so far, but wanted to check before I break something by putting it back in!

Thanks again all for the input. I have gone a little off-piste in then end, with an eye on super-portability. Here's what I'm planning once all the parts are in stock, critical opinions welcome:

• ZWO AM3
• Redcat 51
• ZWO ASI2600MC-DUO
• Optolong L-pro LP filter
• Pegasus power box advance for power/USB hub (already owned)
• Raspberry pi for control (already owned)
• Dew heater on the 51 (already owned)

My rationale is that makes the setup super light- just the scope and the ZWO OSC that has a built in guide cam, so no need for separate guide cam, scope etc. so I won't need the capacity of the AM5 or similar as the total payload should be around 3kg.

Downsides is that this option is super expensive, that camera isn't cheap nor is the Redcat, and there the risk of under-sampling. Though after much reading here and elsewhere, it seems there's a lot of successful people undersampling but then using dither/drizzle to solve.

Thanks all for the great input.

17 hours ago, Elp said:

You could use the evoguide as the main scope, it works well. Needs the flattener and other bits to setup.

If not, many camera lenses work well too, the Samyang 135mm F2 is one of the best imaging optics for astro and it's not even designed for it, beats most astro specific equipment due to it being small and supremely fast.

You'll still need a filter drawer, or can screw filters into the front of flatteners if using most astro cameras because many let all wavelengths of light through so you'll have to block the IR with a UV/IR cut or luminence filter otherwise you'll get star bloat.

If you've got the funds for it, a HD mount will be excellent, I've got a hem15, ever so slightly smaller than the am3.

How are you going to control it? An Asiair makes things simple via mobile phone control, Stellarmate on an rpi also has a phone app.

You can just use the 1600, but I assume you want short session quick results with OSC.

Good shout on needing an LP filter, and wonderful idea using the guide scope, never thought about that! I see some complaints about backfocus with it, so I'll do some more research. I'm using an Rpi and the free version of Stellarmate + laptop which work

15 hours ago, PhilB61 said:

I take my full OSC imaging setup away on regular long trips to France and Spain but as we travel in a 6m campervan I don't really have to worry about size or weight, so can't really offer advice on that aspect. What I can say is whatever combination of gear you end up taking especially the imaging software/hardware make sure you have tested and used it for some imaging sessions before you go. It's a pain having to download and reinstall software, update firmware and generally trouble shoot when it's being done on your phone. Make a list of all your interconnect power and data cables so you don't leave anything behind, getting spares might be impossible if you are somewhere remote and just difficult anyway when not in your home country.

Very good shout. I'm a checklist weirdo just for remembering to pack enough underwear, so will be adding an astro section!

18 minutes ago, 900SL said:

My response is bias driven and a result of my own purchasing decisions and  experience, so take it with a pinch of salt

My portable rig is a Nikon D5600 or 533MC Pro, filter drawer,  Redcat 51, AsiAir mini, Fornax LT2 tracker, ZWO EAF and Blackcat focuser. No guiding, no guide scope, no goto. I plate solve and adjust RA and Dec by hand to find targets. 

The Redcat is a great short focal length scope. ASI Air for PA, plate solving, focus, capture etc. Fornax LT2 tracks at 1" PE without guiding, so 3 min exposures at 250mm are spot on, no egg shaped stars 

Lovely, I was wondering for such short usage, OSC, no very long narrowband exposures plus a decent mount I could probably get away without a guide scope. Star trackers scare me though, before I had a go-to I was rubbish at centring targets so computerised go-to and plate-solving saved the day!

So I'm going to the southern hemisphere on holiday soon, to a bortle 4, (I live in a 5 in the UK) and I'm considering building a travel rig to take with me. However, whenever I price this up it get's pretty expensive, and I've got some questions on the parts, so interested to know people's experiences and ideas. Some background:

• Where possible I'd like to recycle parts from my existing rig, without making it super hard to put back together. This is a HEQ5 (too big and heavy to travel), William Optics ZS73 (not huge but probably a little too big to travel), ASI 1600MM-Pro camera, ASI-120MC and Skywatcher Evoguide for guiding, filter wheel, electronic focuser, Pegasus Power Box advance for power, a Celestron small power tank and a Raspberry Pi/EKOS/Indi for control.
• As travel is not frequent, the whole kit should be usable as a normal rig in the back garden.
• It should be robust enough to experience the usual bumps and knocks you'd expect going through security, in the back of a car etc. so maybe an APO over a Newtonian?

So here's my idea:

• Redcat 51 APO: it's a tiny scope, wide field, has a decent focuser and Bahtinov mask so I can dispense with needing the ZWO EAF, no need to buy a secondary field flattener etc.
• Replace the filter wheel with a filter drawer to slim down the size of the overall package, but I'd need to buy new filters as mine are unmounted, or just get a one shot colour camera instead.
• Camera: no idea, struggling to find a large frame sensor camera that works with the Redcat 51. I could take the DSLR but I've had much better results with dedicated astro cameras.
• A smaller guidescope like the one from William Optics or ZWO as the Evoguide is quite big, and recycle the ASI-120MC.
• ZWO AM3 (or AM5 if budget allows but is that overkill?)
• Take the Pegasus Power Box, dew heaters and Raspberry Pi from the main rig.
• Carbon fibre ZWO tripod can be chucked in the suitcase, and use whatever I can find around the hotel room as tripod weights.

Hi there! I think the Android version needs updating to support Android 14. It will not install on the latest OS as Google Play says 'This item is not compatible with your device'. Works on phones running older OSes. Have also dropped a line to the bug report email.

Oh I have plenty:

• Those yearly guides to what's in the sky. My time is so weather and personal life dependent, it's more a matter of Googling what's up on the rare nights those two parameters align.
• Similarly, a star wheel. Apps replaced that instantly.
• Fancy eye pieces before realising that what I really wanted to do was astrophotography.
• Celestron wi-fi adaptor. Barely worked and annoyed with myself that I never tried to get a refund at the time.
• Polemaster. Wicked bit of kit but no longer needed now astro software can do it with the primary scope.
• A house with a neighbour who loves his leylandii trees being tall enough to rival the Shard.

If I were to call our my best purchases it's not a telescope, mount or other piece of pricey hardware: it's velcro. The best thing for cable management!

Thanks both, I had dismissed amp glow on the basis it's doesn't look like the common examples you see online. As you say, it doesn't seem to impact my images so I will continue on!

I've had this camera a few years now and it's always had the same problem, if it is a problem. Here's a stretched 180s dark frame, no stacking, processing etc. apart from auto stretch:

This is with the camera disconnected from the image train, lens cap on and in a cardboard box with the gaps taped up (for testing, obviously this isn't great for cooling long term), in a room with the lights off in the middle of the night!

I haven't seen it impacting my imaging, but I'm curious as to what it is. Doesn't look like amp glow.

Any ideas?

Nearly 10 years ago for my 30th (which is in December) I went to the middle of nowhere outside of Tromso to see the Northern Lights. While it was an amazing holiday what I saw was a lot of cloud and snow! As my 40th rolls round the wife and I are considering Longyearbyen for next December, to see the lights and maybe get some astrophotography in a class 1 Bortle whereas I'm in a class 5.

But, being December if I look at the Clear Outside page right now, it's 100% cloud again. So I guess luck of course will play a role, but has anyone been this far north or indeed live in the area and offer any advice? I don't have to go in December, we could go another month where it makes more sense. Though the idea of actually being able to do astrophotography at a time other than 2am sounds like heaven!

Thanks all for the constructive advice, lots to read up on and research, but sounds like I've got some good ideas from you all for trying to improve the image (plus waiting for another clear and free night to get some shorter subs).

On the topic of clipping- what are you looking for in the histogram to see clipping? Are we talking data right at either end of the spectrum and also maxing out the top of the graph?

Hi folks,

Recently I've moved to a mono camera setup and managed to get a couple of nights imaging earlier this year. Finally I've had a little bit of time to have a stab at processing them, so I've included the final result and my steps below and happy to receive critique and advice as this is the first image I'm quite chuffed with sharing, but I can see a number of areas for improvement still. I'm also very much a beginner at PixInsight and it's thousands of options.

Final Image

Image Capture

• HEQ-5 Pro with belt mod
• William Optics ZS73-II with field flattener
• Skywatcher Evoguide ED50 guidescope with ASI120MC-S guide cam
• ZWO ASI1600MM-Pro
• ZWO LRGB and Ha stock filters
• ZWO electronic filter wheel electronic auto focuser
• Astroberry/Kstars/EKOS/PHD2
• 26 red, 15 green, 15 blue, 30 L, 7 Ha (didn't use the L in the final image, see below), all 120s at -20c. So excluding the L, about 2h of subs. Had one night capturing the first 15, then a second night that I got some more red, L and the Ha before the clouds rolled in.
• Dithering after every frame and autofocusing on each filter change
• Darks, flats using paper over the lens and pointed at daylight method, no bias (understand no value in bias for this camera)
• Bortle 5 officially, feels darker as I'm on the edge of a small down, but for Orion pointing over the haze of the town centre + moonlight

Image Processing

Using Pixinsight alongside Light Vortex Astronomy tutorials:

1. Weighted batch pre-processing of subs to align and create masters for each channel, used default options
2. Dynamic crop edges caused by dithering
3. Dynamic background extraction on all channels to get right of some of the light pollution and a gradient (though luminance was a failure as it found loads of bad points, but I pressed on and hoped for the best)
4. Linear fit
5. Chanel combination on RGB, background neutralisation (didn't seem to make much difference) and then colour calibration and SCNR to remove a lot of the background gradient
6. LRGB Combine, but this created a muddied image so trashed it
7. Added Ha data to RGB using PixelMath
8. Lots of stretching using Histogram Transform

Raw images (all auto-stretched)

Red

Green

Blue

L

Ha

Master Dark - note the vignette, this is with the camera detached from the image train, lens cap on, in a boot sock and in a closed cupboard. This doesn't look right.

Master Flat for blue - looks okay as I think as it's picking up the dust motes and vignette, but does it look 'wispy'?

RGB combined and L stretched prior to LRGB combine

LRGB combine (thrown as I couldn't get this looking better even with further stretching)

Including Ha - the raw image, then with DBE, then stretched

May have made the final stretch too dark.

Final image, rotated and cropped again.

Notes

• I haven't quite mastered masks so I haven't done anything with noise (when I tried a lot of the detail disappeared).
• Similarly I haven't tackled the stars, bloat etc.
• The middle of the nebula was hard to avoid blowing out when trying to bring out detail elsewhere.

Thanks for making it to the end!