Getting the best performance from my AM5
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w7ay In case you don't believe 12 stars is possible from ASIAIR, here is a screenshot I
I went back to the Phd2 manual as I was having doubts..Here is an excerpt from the manual:
"When this option is enabled, the Auto-select function will identify up to 12 stars in the field of view that have adequate SNR. No more than 9 of these will be used at any one time, but the remainder will be used to replace secondary stars that are lost or rejected for some reason."
So only 9 stars are used to guide with Phd2. That's what I am consistently getting. Sooooo the ASIAIR is better in that regard. Take the win guys! ;-)
w7ay Yes, I see those options on all of my mounts except for the AM5.
w7ay i bumped up my gain last night on my 290mm mini to 300 which is high gain setting and I was getting 12 stars too. Asiair did however pick 11 good stars and 1 very saturated star… which concerned me a bit. Cheers! Guiding was a bit better at 0.6 to 0.7rms and i am ok with that but without being able to adjust the guide rate it seems crippled as you said!
Kevin_A Asiair did however pick 11 good stars and 1 very saturated star…
Use single star mode (click on the star before guiding) to take a look at the ADU (based on 8 bits, on the small window showing a curve through a star) to see if it is saturated -- if it is saturated, ASIAIR should not pick it when autoselecting stars in multi-star mode.
If it is really picking a saturated star (useless for determining centroid), you have come across a bug that I have not yet stumbled on in ASIAIR (believe me, there many bugs in the ASIAIR multi-star guiding, including not be able to guide for a couple of hours at a time before you need to stop and restart guiding to retain the reference stars).
If you want to exclude a star that is borderline saturating (scintillating between saturation and not saturated), either reduce the gain or increase the gain some more (again, don't be meek with the gain control). The latter is preferred since the SNR distribution of the remaining stars (used as weights of the centroid calculation) may be more even.
Don't ever let any saturated star through at any time, even momentarily. The centroid will be completely wrong (jittering all over the place) and because if is so bright, the SNR will make the (wrong) centroid dominate over the centroids of all other stars (i.e., turns into a one-star autoguiding on a saturated star). ASIAIR should already handle this, but I not seen its GUI drop any momentarily saturated star.
Chen
w7ay all of my stars were looking like the hole of a dounut in the green circles but 1 star filled it completely…. My guiding earlier before this happened was about 0.5rms but after I re did my guiding and it picked a big star too… it went up to 0.7rms average. I tried to have it pick other stars by moving slightly off target but it seemed determined it wanted this huge star in its grouping at all times. Nominal unity gan is 110 so at 300 i think i should be ok. I have asked zwo why they are blocking guide rate options in asiair for the AM5 mount…. Waiting to see their response.
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Kevin_A My guiding earlier before this happened was about 0.5rms but after I re did my guiding and it picked a big star too… it went up to 0.7rms average.
That is what I would expect.
Remember that I'd mentioned earlier that your autoguiding is now limited ("tall tent pole") by something e;se other than the sawtooth. I.e., in this case, bad centroids are being computed.
I tried to have it pick other stars by moving slightly off target
In the good old days, we can pick different stars by adjusting the bolts in the guide scope tube rings, or with x-y stages with fixed tube bands. You don't even find the x-y stages being sold anymore.
https://www.sciencecenter.net/hutech/borg/guidescopes/attnov08.pdf
(By the way, that article is written by Craig Stark, the author of the original PHD. Even back then, nobody would use a 30mm aperture "guide scope" with 4 arc seconds Dawes limit -- but ZWO will sell you one.)
Nowadays, it is easier, since we have larger cameras (much larger than the miniscule guide cameras back then). But things like ASIAIR have chosen to cater to the novices ("Easy..."). And they believe that the simpletons cannot learn anything new, and be capable of picking their own star distribution.
(If you haven't noticed, ASIAIR is not conducive to learning. I don't know how these addicts will learn anything about astronomy.)
So, those of use who use ASIAIR will need to work around the crippling. In this case, purposely steering the gain of the guide camera to purposely saturate a star or two. To get more even distribution, especially in the star dense Milky Way, I often increase the gain to purposely saturate 3 stars, just to exclude them from swamping the centroid weighting.
Just tune the gain so that the brightest star that is picked does not scintillate between saturation and non-saturation.
Chen
w7ay i learned the old school Phd2 way but over the last year I decided that I did not want to sit outside with my laptop in the snow or pestky mosquitoes from living near a pond so I decided asair would a good choice so i can image frim my couch without. 30M ethernet cable from the door…. But I didnt think they would cut out so many needed features and what the fudge… no guide rate options for their own mount??? WOW! No words can be said about that my friend. I appreciate your comments and I appreciate that it mainly stops me questioning my own sanity. I am ok with my overall guiding numbers and the sanity check you provide only cements my suspicion that there are some issues with most of their products that are finally coming to light.
Cheers! Easy as 1,2,4 (3 isn’t in the menu options it seems) haha
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Kevin_A i learned the old school Phd2 way but over the last year I decided that I did not want to sit outside with my laptop in the snow or pestky mosquitoes from living near a pond so I decided asair would a good choice so i can image frim my couch without.
Place a laptop or a Raspberry Pi 4 outdoors (just like ASIAIR), running INDIGO (INDIGO Sky in the case of Raspberry Pi) and control it from indoors.
Indoors, you can run anything from a web browser (since INDIGO includes an HTTP server).
https://bbs.astronomy-imaging-camera.com/d/15898-asiair-v21-has-been-released/124
Easy as 1,2,4 (3 isn’t in the menu options it seems) haha
To paraphrase that crazy Herr Einstein, things should be made as simple as possible, but no simpler.
Chen
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Practicing what I preach...
I just started to write the code to support my second iteration of an All Sky camera.
The first version used an ASIAIR, with a pancake version (uncooled) of the ASI178MC and a 3.2mm CCTV lens (higher quality that the stuff ZWO gives away for free, but still just a CCTV quality lens). WiFi. Power through a 12V source.
This version is using INDIGO Sky on a Raspberry Pi 4. The camera is an uncooled ASI294MC. The lens is a Sony-E mount version of the Samyang 8mm Fish-eye. Interface will be Ethernet with power from PoE through the same cable. The ASIAIR just is too crippled.
The lens went from this
https://www.amazon.com/gp/product/B08GLYR572
to this
https://www.amazon.com/Samyang-Fisheye-Mount-Cameras-SY8MBK28
I have just started modifying the (macOS) program I had written to work with INDIGO so that it is specialized for All-sky and Meteor captures (my plan is to do frame subtraction to only record frames with meteors -- avoiding aiplanes is going to be challanging).
The "Preview" screen from the original program will be used to capture and saving images. So far, it still has the stuff to control focusers and filters, and a histogram. Those will be removed and replaced by all-sky and meteor specific control in a different window -- I want an All-Sky display to be no-nonsense, with nothing but a view of the sky (and trees, in my case :-).
Hey, notice the two parameter histogram adjustment (the little green arrows) to get proper histogram balancing (not like the single parameter on on the ASIAIR app-- again, another "too easy," thing in ASIAIR).
Now try to do all this on an ASIAIR. Even when you are not my 75 years of age :-).
(Right over my head is my FSQ-85 stored on the second RST-135 that is on a Gitzo tripod.)
Chen
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w7ay awesome! It is a shame that ZWO does not utilize your knowledge to improve their products. Practicality and understanding is something that is lacking in product and programming these days. I too am getting old my friend… I try to pass on the little I know but people want it easy and ready to run without caring about understanding it…. They only care when it does not work, while not trying to learn. Cheers!
Kevin_A It is a shame that ZWO does not utilize your knowledge to improve their products.
Actually they ask me a lot of questions through email. But they seldom take any recommendations. I knew about the ZWO mount development more than a year ago. Just recently had a question on an announced feature in an announced proct, but they have no idea how to implement it.
Their aim is very different from mine. Mine is to spread knowledge, theirs is to make money from the naive.
Chen
w7ay i am definitely not as knowledgeable as yourself in these field but do share the same views and similar sharing goals. My background is more of a multipotentialite. I have many hobbies and background skills ranging from photography , mechanical engineering, an artist, naturalist, psychology and what I learn and discover, I try to pass on to others to help them learn. These days it seems most people do not feel the need for understanding, they just want instant gratification. The world as we know is changing and we can thank greed and corporate for that. I just released my latest artwork to a gallery last week and it sold in 3 minutes… it is called “ Perspective”, it is about finding beauty, happiness and good things in life that matter in a world so cold, greedy and influenced. By using your own mind and spirit you can change anything. Lots of cloudy nights to keep myself busy these days… so I do many things… just not in all the same ways.
Have a nice night!
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w7ay i did manage to get 2 hours last night on M13. Almost a full moon and guiding was at 0.7 overall during the night. I am not sure if the lower 200ms pulses affects the calibration process but I did notice that during the cal process, the stars seemed a bit offset when switching axis… kind of like it was strugling to get the star back on axis causing a big initial error correction when finally switching from calibration to guiding. It did 12 steps in each axis… It then caught up when guiding started and then held the star in the 12 green circles. When cal switched from e to w to n to s the main star was above the dotted line not on it. Not sure why, even when backlash clears 2-4 times.
I may even remove the covers and check for belt backlash soon. I have noticed this issue a few times now… but not everytime. This is not a issue to me but more of a lesson to be looked at.
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Kevin_A i did manage to get 2 hours last night on M13
Nice.
M13 was (back in about year 2001) the first time I realized how much Richardson-Lucy (blind deconvolution) can sharpen up even defocused stars.
Back then, the Hartman mask was worth the cardboard it was cut from. Pavel Bahtinov changed it all (and the ASIAIR "auto focus" took us back a step again -- it is sad to see humans devolving, just to make a few bucks). But focusing a star to a pinpoint was really tough without diffraction masks. Today's focusing the Sun is equally hard, since there is no point sources at infinity during the day to use diffraction masks like the Bahtinov.
I started using my own M3 images from the f/6.3 8" Meade images for use at work to experiment with image sharpening. Apple's Accelerate group (one floor down from my group in the same building :-) got wind of it and was impressed enough with R-L that they hard coded Richardson-Lucy into their framework. All because of a fuzzy M13 image :-).
You can read about the Accelerate framework here:
https://developer.apple.com/accelerate/
I still swear by the FFT algorithms in that library today. Faster than a speeding bullet :-).
By the way, Meade made the f/6.3 for only a limited time. With a 0.63x reducer, it made that 8" an f/4. Then they got sold to a Chinese company, which then got sued out of business a couple of years ago for shady business practice by Orion. The Meade part was subsequently taken over by Orion. MEAD used to be listed on the NASDAQ even.
Chen
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w7ay i still use a bahtinov mask today for focussing initially and use that as a reference number on the asiair eaf during the later part of the night. I was impressed last time imaging with my askar fra300, as I fixed its overly tight focusser that was affecting the eaf severely and my eyes said 3760 and eaf came in at 3760 too, so my eyes are still working fine with a mask! Haha My Meade 6000 series 115mm triplet is still my favorite scope from 6-7 years ago. Only FK61 but a good optical design for its price. I am wondering if my fan on the 2600mc pro has a bit of vibration as it is a bit more rougher than my 533 and 183 smaller cameras…. I need to test that out as I have a slight bit of elongation and bloat. More things to check and there has been widespread thoughts on how zwo mounts it fans and if it is isolating any vibration or contributing more to it. I could try adding a better sorbothane o-ring washer duro 40 but that is still up for thought.
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Kevin_A I am wondering if my fan on the 2600mc pro has a bit of vibration as it is a bit more rougher than my 533 and 183 smaller cameras….
Just change the setpoint temperature so that the fan is just off, to measure a reference star size. Then change the setpoint so the fan just turns on (this way, off and on only changes dark current noise minimally just in case it affects the FWHM calculations).
Take a few exposures with the fan off and a few with it on and take averages.
Send the images to some program (like AstroPixelProcessor) that analyses the FWHM.
Do not trust the HFD numbers from ASIAIR - it is not accurate, and depends on the background light level -- you may have noticed that ASIAIR HFD (when "auto-focusing" and with Star Detect tool) gives better numbers before it gets full dark out of astronomical twilight. Well, just another of ASIAIR's bugs.
See if the FWHM changes from fan off to fan on.
Unfortunately, Noctua does not make the larger (thicker) fans used in the larger ZWO cameras (2600, 6200) etc. They do make one that will fit the older cooled ASI183. Otherwise, it is a high quality European fan, with integrated anti-vibration pads instead of external grommets.
For now, the best you can do is to add some rubber grommets (which should have been there in the first place), or switch camera manufacturer (I recently bought the QHY version of the cooled IMX533 sensor instead of the ZWO cooled ASI533).
Chen
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Kevin_A The camera came with orange grommets but i will change them to a better material and repeat my tests.
The orange could indicate that they are silicone instead of rubber. Silicone can remain pliant with lower temperatures; so you may want to keep the silicone ones, or get thicker silicone ones.
Rubber O-rings tends to be spec'ed to something around -18ºC, and silicone can go lower (I have seen them spec'ed to -50ºC, gulp).
But if you won't go outdoors below -18ºC (I won't even take my telescope out at 0ºC :-), then the rubber ones should be fine, especially if they are more vibration absorbing. You just need to do some "before/after" tests. BTW, you may be able to do this with artificial stars indoors on a cloudy night -- that's why everybody who does any serious astrophotography need to own a good artificial star.
However, if the current grommet is no good, it only gets worse with lower temperatures. I'll bet ZWO will release some new fans that have the proper damping, and make everyone pay again. They did this with leaky filter trays etc. You end up paying more in the long term than buying a higher quality product at the beginning.
Chen