AstroPhil

Yep, very interesting (and slightly annoying). I'd be really nice if there was more information/test report sent with flatteners (such as backspace measurements with focal length, or focal plane curvature detail) as they all seem to just state that one back focus of 55mm when often it is somewhat depedent on what FL scope it is paried with... there's surely more info (or a method/formula) out there rather than just trial and error...

Quick update. After some playing about with back spacing the other day I *thought* I had cracked it with 69.5mm (would have gone with 70mm, as some posters have been recommending, but if I did that, the focusser could not quite focus the image at all. So 69.5mm it is). But tonight a 5min sub gives the below (taken just 20 mins ago). So, not sure still. The lower right corner is particulary bad... I suspect that the focal length I'm trying with is just a bit too short, and out of spec. Back to the Askar reducer/flattener I think...!

Thanks all for the thoughts... yep, if I need to use the reducer then so be it. At this point I am curious to solve the mystery though! I did also see that there is a table of data that goes with the StellarMira adjustable flattener (the one I am using is the fixed type but I assume they are very similar optically) and that suggests shortler FL needs longer back focus (here: https://www.firstlightoptics.com/stellamira-telescopes/stellamira-2-adjustable-field-flattener-with-m48-adapter.html))

So at the very least I'll try, and and see if the stuation improves, I guess.

Hi all,

I've been trying to use an Askar FMA230 at it's native focal length (275mm) by using a StellarMira 2" flattener, coupled to an ASI533MC cemera. But when I use the recommended back spacing of 55mm I get the dreaded comet shape stars in the corners (screenshot-1 below: all 4 corners look the same, 'tails' pointing towards the centre of the FOV, I just use one for illustration purposes below). I note one of the reviews on FLO did suggest that 55mm was too small and 70-75mm is better. I'll try that out once I get clear skies. BUT the odd thing is that when I use the bare OTA and no flattener the same issue is seen (this is screendshot-2). The performance with the matched ASKAR 0.84 reducer/flatener (taking this to 230mm) is fine (screenshot-3). These are all single frames, 120s exposure, using Optolong L-extreme filter, with stretch, debayer, and gradient removed.

So, just curious if anyone has seen/had this before with similar setups/flateners? Or has any pearls of wisdom as to how to calculate/determine backspacing? If not, it's trial-and-error, I guess, assuming this really is a backspacing issue... If not I guess I'll be using Askar's flattener and 230mm FL!

Cheers, Phil

I have the DL version, and can attest to the FC100 quality. It's a fabulous all round (visual) telescope, light and portable.

Yep, I don't own an ASIair but so far the AM5 works just fine with INDI/KStars (tweaks+tuning aside). I'm (perhaps) a bit old school when it comes to PA and I do like a standard polar aligning scope (doesn't need a computer/power at least!). But, having said that, the routine in KStars works very well indeed: sounds like the Asiair version is easy too.

The lack of weights bar was less annoying (to me) that a decent manual to be honest, but so far the ease of setup (and light weight) of the AM5 is superb. And the guiding is excellent too. So far so good...

I’ve had this for around 3 weeks now and although it was shipped with the standard FLO clouds these quickly cleared and I was able to use it around 6-7 times (nights) as of time of writing. I purchased the mount to replace a Skywatcher Az-Gti as it couldn’t quite manage the payload I needed for a rooftop based (the only place I can really see the sky) wide-field imaging project using an Askar FMA230. I am sure it’ll be used with other scopes and also on travels as well. Although the list of things I don’t like is rather long, I would stress they are all minor, don’t affect functionality, and have all been addressed. Overall, it’s an excellent mount (particularly, I believe, for ASI-Air users).

Things I like:
- It really is rock solid, very well engineered, and a counterweight is not needed for my 5Kg wide-field rig. I’m sure it’ll cope with a Williams Optics Zenithstar 71 later on as well. The light weight and stability is just outstanding. I will also use it for outreach, rather than lugging my old Vixen SP and counterweight. All the controls/locks are butter-smooth and precise. The slewing accuracy and mechanics are first class.
- The app (iPhone in my case) is excellent, and works nicely on my iPad as well, whether connected via a home WiFi or through the mounts hotspot. Unlike the skywatcher Az-Gti app, it’s a full featured planetarium program, and very nicely done, very easy to use.
- Personally I like the simple/small handset/joystick rather than the “full featured” controller (which is basically the app). I don’t miss a handset at all.
- Although some folks think the matching TC40 tripod is a bit short I find it perfect for my application - with the caveat that this is currently used for a very compact wide-field rig. Extended, it is high enough for me (just about!), particularly in Alt-Az mode. I have yet to try it visually, but I can see it being just fine.
- Guiding performance hits the spec of 0.5-0.8”, albeit taking a while to get it ’tweaked’ (see below!). As I type this, the mount is getting 0.55” RMS and I have yet to drop a sub tonight. It’s very impressive. UPDATE, a week later, it was tracking at below 0.4”. I think this is outstanding, considering the unit is so light and portable. The screenshot shows early the early sessions - I/it has improved since this.
- Not having a polar alignment scope was going to be an annoyance… but it’s forced me to try out a more modern electronics/software solution (which I have been putting off!), and it’s far easier than I thought. I used Ekos/INDI for this but similar routines are built into Sharpcap, ASI-Air, and other software packages (as I understand).

Things I don’t like (mostly minor/technical):
- The system really tries to lock you in to the ASI-Air ecosystem and, as I have an Atik camera and filter wheel, and other non-ASI gear, it took a lot of time and research to be sure it’d work (thanks to FLO and many others on various websites and fora!). I’ve now gotten it working nicely with Ekos/INDI and I understand there are EQMod and NINA drivers, etc. as well. But, it took some effort.
- There is no manual to speak of. This really is not great and it took an age to read though various websites and fora to track down answers.
- Whilst the hand controller is included, a counterweight bar is not (I use the Az-Eq6 extension bar which is M12 threaded but without a counterweight as I don’t need it). Ditto, a power supply is not included. Although I have many 12v supplies ZWO might have at least thrown in a few cables into the case (they at least included an USB2 cable).
- The 12v power socket is just a simple 2.1mm barrel connector rated 5A maximum: that’s a lot of current for a rather basic socket/connector. It took me a while to find a plug that sat in there firmly as the main socket is not very deep (I was able to “wiggle out” some plugs/leads). This really ought to have been a threaded connector and use a higher voltage to reduce voltage drops. Then again, the mount technically takes 11-15v (buried in an online FAQ somewhere - details that ought to be in the MANUAL). The 12v side connector seems to be simply wired in parallel - rated 3A. Which is odd, as it means either socket can supply power to the mount, and the 3A socket is not an independent “supply output” (run from an internal DC-DC converter, say). If you put in 14v in the main power socket you get 14v out the side (caveat - I don’t have a schematic, but that’s what the multimeter suggested!). The side connector (which is panel mounted rather than PCB mounted) on my unit is extremely stiff - A Lynx astro silicone power cord can’t get in there unless I force it.
- The INDI/ASCOM driver is a bit rough. It took several nights to get it to guide properly (disabling/re-enabling pulse guiding was one solution) and it seems to have to be briefly connected to the ASI app to get time/position data before the INDI software will allow it to GoTo/slew in KStars. And because the WifI antenna is in the hand control this means the hand controller needs to be plugged in to do this: once it it set up it can be unplugged and controlled via software. And unparking the mount via INDI means first pressing “track” then “unpark” rather than just “unpark”. So, there are a few bugs for the non-ASI Air crew to deal with still (well, this one anyway!).

On the guiding, I’d also add that my 30mm/F4 astroessentials guidescope (using an Starlight Express Ultrastar camera) initially didn’t manage an RMS error below ~2-3” but when I swapped it out for a EvoGuide ED50 from my other rig it immediately decreased to around 1” (with 1s guide exposures). Then, with a better polar align, I finally got it down to 0.5” which is where I am now (plus with tweaks to the autoguider settings inside Ekos/INDI). So, it’s on spec, eventually.

Overall, I’d give this 9/10 purely as there are so many easy “tweaks” that can be made to make it better - both for ASI and non-ASI folks. Not to mention improving some of the electronics and connectors (and documentation).

Phil

Hi All,

Another happy AM5 owner here: I'm making steady, but very slow, progress getting a ZWO AM5 mount to work nicely with my INDI/stellarmate setup. Just wondering if anyone here also uses INDI/stellarmate rather than the ASI Air / NINA? I'd particulary be interested to hear of recomended settings for the RA/Dec agressiveness and other parameters (integral gain etc.) that they find to work? I did not get below around 2" RMS last night -albeit this is using a very short FL guidescope (120mm/F4).

I also note a few "INDI oddities" to get it to connect/slew/GoTo. First of alll the mount needs to be breifly attached to the ZWO app to get date/time (I think) info then the slew/goto works in Indi (and at this point the handset can be disconnected. But it'll still "park" without that step. However, unparking does not seem to work - I have to "start tracking", then "unpark" then it wakes up and actually unparks. And then getting the guiding calibration to complete seems to have a bug - it calibrated in RA forward, but the reverse never completes (it seem to go forward an never actaully reverse, just thinks it does). I fixed it (thanks to a comment from kd6awa via Der Pit on the cloudy nights forum) by briefly stopping pulse guiding, then re-starting (re-enabling) it... and then sending a few 0ms pulses manually though the INDI control panel. Then the guide prep completes. But, what a palaver!

Once guiding got going it never really got below 2" (which is fine for my widefield needs) let alone the published 0.5-0.8" - but maybe the Asi air driver is "better" than the INDI one?

Any other AM5/INDI users out there with thoughts/ideas?

Cheers, Phil [PS posted also to the INDI forum, but thought the SGL community might be interestd as well!]

On 05/03/2022 at 16:25, AstroNebulee said:

It's a lovely set up there Phil, I love what you guys are doing with the evoguide and lenses. Regarding set up weight I use the star adventurer tripod that you can buy with the az gti and the total weight on the set up is near 6kg! The scope, guidescope, asiair and 294mc pro all come to 3.9kg but add on the 2 kg of counterweights takes me quite high. 

Well the rig made it to Chile and back! - some pics here for anyone interested. Loads more to process though!!!!

The Hubble palette version of Triffid is here (and others!)... not sure if links to flickr work! but lets see!

https://www.flickr.com/photos/194710934@N05/52122570046/in/dateposted-public/

In April I had a business trip to Santiago, and of course couldn't pass up the opportunity to spend a few extra days to the North, in the Elqui valley, with "some" imaging gear (causing much interest at the airport!). I'll still processing the data, but below are a couple of teasers. I'm sure these will also improve over time, as I get better with PixInsight. On the imaging list were the triffid nebula, Lagoon nebula, the region around Antares generally, Carina nebula, prawn and seagull nebulae. The setup was an Askar FMA230, with mini guidescope and an Az-Gti in equatorial mode for guiding (controlled via INDI/kstars). Managed fairly decent tracking, most of the subs were 2 minute (any longer than that, and things got a bit tricky!). And the camera is an Atik460+filterwheel.

I definitely feel the pain of the OP - been there too. Took an age to get everything running via EKOS/INDI. A combination of the latest version (with the stellarsolver), plus wired connections for everything, and decent power supplies all helps. And practicing in the daylight! Oddball slews running off in the wrong direction (and then hitting the software limits) used to be my pet peeve, eventually solved once I'd fixed the home/parking "definition"... 

On 23/02/2022 at 19:08, rl said:

I'd give the mirror a wash, collimate and check it out on a decent night first. The pre-zygo mirrors could be a bit variable to say the least. The early cells were a bit agricultural. It's going to be a couple of hundred to fit a new focuser and re-coat....

"agricultural" certainly fits with my experience of my c.1992 OO 8" newt! ...which I still have 😉

36 minutes ago, Adam J said:

A 50mm guidescope is serious over kill for a 230mm focal length imaging scope. Get a 30mm and it will solve some issues for you. 

Ha! Indeed it is! But, it's also what I have from another setup, and I'm trying not to add more bits-and-bobs to my collection at the moment...!

Yep: on paper the fotomate tripod should just about cope with the weight, but using the tripod head to get the latitude angle makes it a bit less stable! I actually have a spare sywatcher tripod, but no wedge, so I guess I'll have to make a trade-off between solid AltAz or dicey Equatorial at some point!!!

On 27/02/2022 at 21:58, scotty38 said:

That's correct but the process container automates the application of the processes contained within and that in itself can be applied to an image container containing, well, images....

I've not heard of this! I'll give it a go, sounds interesting. Cheers for the tip!

On 27/02/2022 at 15:56, AstroNebulee said:

Really pleased you've got vthis mount now, it's a beauty. Regarding your poor guiding, I suspect the poor PA and windy position wouldn't of helped you in your guide rate. I use my set up in EQ mode via an asiair pro so can't be of much use with the raspberry pi and I'll get around 0.5-1.5 guiding on a good night. Could you send a picture of your set up. 

Cheers 

Lee 

Hi Lee, here's a setup picture (the guidescope is going to get moved at some point to the other side of the lens, opposite the RPi, to impove the centre of mass). The setup is probably too heavy for the tripod, but am hoping it'll still be useful for an ultra portable rig....

On 27/02/2022 at 16:45, Elp said:

It was windy last night and I was getting 7-12 typical average guiding, it was awful and couldn't really image anything. So I tried m45 pleiades at 10s subs which just about worked. Any other target other than m42 Orion nebula in such conditions I think would be impossible.

I suspect this was my issue as well! Once the skies clear I'll have another try - cheers all for the great suggestions; excellent thead!

A few weeks ago I took delivery of one of these nifty little mounts for travel (pending trip to Chile coming up in late March!), and to go on top of my fotomate tripod. And on Wednesday also received an Askar FAM230 scope/lens as well. Despite the "may contain clouds'" warning sticker from FLO last night they both had a trial run via a few choice objects (Pliades, Behive, Pinwheel galaxy). I have to say I'm impressed. Took me a day of tinkering Satuday to get it all together (as I wanted to use a spare Rasperry Pi running KStars/INDI) but got there ins the end.

The only query I have so far (albeit with only 1 night of practice!) is around the driver and guiding: there's the usual Eqmod mount driver in INDI, but also what I assumed was the correct Gti driver - but this didn't seem to work so I reverted to the Eqmod one which did work. Hopefully that's right (anyone who images with this rig maybe you have pearls of wisdom here?). The guiding accuracy seemed rather hit and miss (5-20"+) but then again I expect I am testing the capacity of the mount here (CCD, filterwheel, counterweight) plus any innacuracies in my quick/rough polar align. I wonder if there are any tricks other users have found for getting decent guiding performance in terms of mount settings etc.? (caveat - it was a raher exposed/windy roof location so I was not expecting miracles for a first time run!).

Anyway, overall very pleased with the setup very portable, decent price. Just need some more practice now. Clear skies all.

Phil

There's definitely a steep learning curve to PI - I almost have to "re-learn it" each time, particulary with the different sequences of processes. I've often wondered why they cannot come up with a graphical script that can be 'saved' and then simply add/change input files and/or parameters (not talking about the batch sequence process though). The re-run the whole thing in sequence rather than forgetting ones place! When I worked in the Oil/Gas inductry a long time ago there was a software called ProMAX that did this....

I only managed around 15 minutes each [L-R-G-B-Ha-SII-OIII), but so far so good with my first attempt at narrowband imaging from my fabulous Bortle class 9 central London location 😉. Processed using various palettes... 

I'd say that's awesome! I'm very jealous: my own attempt is below, but taken from cenral London(!) and with limited field of view (straight up, more or less) from my back yard. So I managed only 20 minutes each of L,R,G,B... Somethinig to add to in the future (plus, this was my first attempt using a new Atik 460 and filter wheel) from darker skies...

As per the title really, does anyone know how to do this? I keep chaging to my prefered buttons on the EQMod mount/joystick tab for slewing etc., hit 'save' under the configuration, but.... nothing. Have to set everything again each time. Same for lat/long location and other preferences, and the rest. Am I missing something? Does the 'save' not actually 'save' these settings? Can it be done?

Thanks and apologies if this info is out there - I am googled out and none the wiser!

Phil

1 hour ago, John said:

After a little initial tweaking I rather like the Tak R&P that my FC100-DL has. It's F/9 though so perhaps dual speed is less essential, at least for the purely visual observer like myself ?

I have a Moonlite on my ED120 and a Feathertouch on my LZOS 130 which are also very nice though. If I was to change the focuser on the Tak it would be to a Feathertouch. It makes even the Moonlite seem a little ordinary.

 

Yeap, the focusser discussion regrding Taks has some history, for sure! I put a feathertouch microfocusser on my FC100DL, but often think about putting the origional back. Then again, I'm sure I'd miss the fine focus... definitely a condundrum!

Sucess!

Took a weekend of googling but turned out my code was entirely 'barking up the wrong tree' as it were. Here's the final design and code, in case anyone else is interested. This uses an arduino MKR1010 and a MKR Ethernet shield (which I had spare: see photo), coupled to an NEO-8m GPS chip from AZ-Delivery. My motivation here was to provide my (new portable!) rig with a method to import location and time across the network to the two Raspberry Pi's I have mounted. Works a treat with the Ekos NMEA driver: all of this is a local network, so completely independent of the home network - hooked up to a laptop using a single ethernet cable.

P.

#include <Ethernet.h>
#define LF          0x0A
char data[200];
int idx;

byte mac[] = {0x54, 0x52, 0x49, 0x41, 0x44, 0x00};
// byte ip[] = {192, 168, 1, 128}; // for house network
byte ip[] = {169, 254, 95, 128}; // for closed network
EthernetServer server(50000);
EthernetClient client;

void setup() {
  Serial1.begin(9600);
  idx = 0;   
//Serial.println("Ethernet WebServer");
  // Start the Ethernet connection and the server:
  Ethernet.begin(mac, ip);
  // Check for Ethernet hardware present:
  if (Ethernet.hardwareStatus() == EthernetNoHardware) {
    Serial.println("Ethernet shield was not found.  Sorry, can't run without hardware. :(");
    while (true) {
      delay(1); // do nothing, no point running without Ethernet hardware
      }
  server.begin();
  client = server.available();
  }
}

void loop() {
//Serial.print("server active at ");
//Serial.println(Ethernet.localIP());
  while (!client){
      if (Serial1.available() > 0){
      data[idx] = Serial1.read();
        if (data[idx] == LF) {
          data[idx-1] = 0;
//Serial.println(data);
          delay(10);
          server.println(data);
          idx = -1;
          }
      idx++;
      }
    }
}