ONIKKINEN

24 minutes ago, alacant said:

Had a go at the stars. Maybe have a look at polar alignment?

Looks like the elongation is along the RA axis, which means the exposure was too long and affected by periodic error.

30s exposures would probably be more reliable for unguided. The only way to get rid of this limitation is to guide.

Just updated both the hand controller firmware and the motor controller firmware. Both were i believe one of the earlier versions of this model of mount so looks like my unit has been sitting in storage for quite a while before i bought it. Motor controller firmware was 03.00.32 and is now updated to 03.15.32. I wish i had a recording of the sound my mount made when slewing before, but it sounds COMPLETELY different now.

Previously it was 100% power the instant you press a directional button or initiate a GO-TO, now there is a built in spool up period and it is a lot less jerky and sudden. Doing dummy tests indoors at the moment and GO-TOs appear to be going to at least the general direction of the object and not 90 degrees off. Time will tell if its fixed or not.

I am not an expert but pretty sure mount electronics dont like occasionally being shorted. I have always used this cable so its entirely possible it has been shorting intermittently for a long time now. Wasn't this obvious, but as i yanked the cable a bit it appears to be completely exposed with a maybe 1-2mm airgap in between. Who knows what happens to the motor controller logic when shorted a bit, maybe even running backwards, going the opposite way or some other bug? Would conveniently explain why it only happens sometimes...

Still doing the firmware thingy just in case.

2 hours ago, newbie alert said:

What mods have you done?

Maybe modifications was a bad word to use. I did a tear down/regrease and polished some surfaces to decrease friction in the hopes of getting better performance. No bearings in the mount so polishing the bushings/sliding bits (dont know what to call them) could help. Didnt improve much, but it is easier to balance now so didnt make it worse. Also marked a few bits and roughed up a thread inside as i didnt have any instructions for the tear down, so im not comfortable sending it back. That one is my fault.

As for the other things, i suggest you re-read my previous comments. Not meridian flip/NINA/Date and time/location/PC-control related.

I find that every degree below -20 adds an exponential risk of failure in moving parts. Focusers seize, maybe the lubricant gets sticky inside the mount, electronics either dont work or work slowly. USB connections especially become very fiddly and weak.

But -43? Way too cold, not that we get those temperatures anyway. Shame, since i have also found that extreme cold also brings extreme dry and with it good transparency.

1 hour ago, newbie alert said:

If it's under 2 years old and within warrenty I'd be looking to send it back unless a firmware update didn't fix the issue...  

How do you mean it slews the wrong way... when the mount flips it looks like it takes the long route sometimes, but it can't flip going the wrong way 

It is as stupid as it sounds, the mount just does not do what told. Not meridian flip related by the way.

An example from the previous case when i was on a purely visual session: GO-TO for M51 from M81 so shouldnt be that difficult of a slew, goes the opposite way and says its there. The "show position" command in Synscan is aware that the mount is not where M51 is and correctly shows the coordinates of wherever the GO-TO slewed. So the mount knows its not at M51 but still went there.

Googling around i found that others have had similar issues that were unsolvesd or solved with firmware updates. Thats my next bet.

I bought the mount from Astroshop and have modified and damaged quite a bit of it so wont be sending it back. Learned from this and the next mount is coming from a domestic shop. Will be thoroughly inspecting and testing before making any changes or maintenance.

2 hours ago, Starflyer said:

I don't know the mount but are you using EQMOD as the ASCOM driver?

I know with SGP and EQMOD there should be no pointing model and sync in EQMOD should be set to Dialogue Based otherwise plate solving will fight with the pointing model, you get all sorts of odd results and the mount will never centre successfully. I guess NINA's centering functions in much the same way.

I'd clear out any pointing model, check your location, time and timezone in all places.  With this done, a decent polar alignment and a decent zero position your first go-to should be close and plate solve / centre should work as expected.

Irrelevant to the issue, since it also happens without PC control. Zero position doesnt matter and shouldnt result in the mount doing a GO-To to the ground when sent to park. Ill see if i can reset the firmware to factory defaults somehow.

But i am using the Skywatcher driver and controlling through the hand controller with a USB cable. Dead simple and both the handset and PC can issue commands. 

My Skywatcher EQM-35 sometimes slews to the wrong way than what the GO-TO ordered, and today was the 4th time this happened. This time with a GO-TO issued by NINA and my astrophotography mini-pc. Previous times have been without computer control, so just handcontroller issued commands. Previously i was able to get rid of the problem by just restarting the mount and doing the initial date/time/location things from scratch but this time it didn't work.

The confusing part is that the mount reads the coordinates correctly, it just doesn't follow any commands correctly. I have a target at around DEC 73, and the first GO-TO is not even close (never is, not the issue). Well then platesolving kicks in and tells me that its pointing at DEC 71 right now and that its outside tolerance and will re-slew. All good, except that it slews to DEC 69. This keeps going on until my max tries setting kicks in and NINA just hopes that its on target and presumes the sequence. Well its not and i cant get it to go to the target no matter what i do. I tried to restart the PC and the mount but this went on and on. At one point i was on target, but then started platesolving to get my camera rotation correct. Once rotation was correct and i tried re-slewing to the target the same circus of going backwards happened. Astap platesolving works like a dream, as it always does btw. Not that it matters in this case since the problem happens with or without platesolving.

Then i just decided i have had enough and sent it to park. Which sent the scope towards the tripod legs and pointing to the ground. Also, at this time NINA correctly noted that i am indeed at below 0 degrees in altitude but still went on with it?? Ripped out all the cables, cursed the thing in unprintable ways, packed everything and headed home.

Any clues? I will assume this is mount hardware/firmware related since it can happen with software and without software assisting the GO-TO.

The mount is under 2 years old and with the new USB on mount handset and control box. All date/time/location settings set correctly etc. Anyone run into similar issues with this model, or some other synscan mount?

A few nights out in -15 or colder temperatures i have noticed that the Baader diamond steeltrack becomes "springy" like the stock focuser in the fine motion knob. Its possible to work around this by carefully adjusting the friction screw to a point where it almost, but not quite slips but its a bit of a faff. It gets better once the entire setup has properly cooled to ambient temperatures, but during cooling i will have to keep an eye on the focus and adjust if necessary. Much better than the stock focuser of course, but if anyone is wondering how it performs in difficult situations i thought i would mention that its not perfect.

But in all fairness, nothing that is supposed to move seems to work properly in cold temperatures, so shouldn't be a surprise for someone who is used to that.

5 hours ago, wimvb said:

That answers the question I had. If ZWO would drop support of other mounts, they could as well discontinue the ASIAir.

What also surprises me, is that this is the second harmonic drive mount I've come across within this last week.

https://www.aliexpress.com/item/1005003408574030.html

Thats a pretty significant price difference... Although more in line with the RST-135.

I wonder if we are heading to a new era in mount designs? Maybe the old worm drive style of mounts is an ancient relic in 10 years now that we are seeing many new harmonic drive designs, assuming one will end up working and be manufacture-able for a decent price?

No 10 billion dollar fireworks! Lets hope the space origami works out.

Third (or thereabouts) the price of the RST-135? New product? No available user experiences publicly available?
I will expect that the first buyers of the mount end up being beta testers, and i certainly wont be one. If it really ends up being a decent product, rainbow astro has to adjust their price accordingly. Also, a bit worrying if it ends up being the case that the RST-135 is priced so high "because we can". Competition will be good.

But, if a fair bit of experience in the car industry has thought me anything its that no new product is ever released in a finished state. The first model of every new car is always faulty in some way that only gets fixed in the second iteration while the early adopters are really out of luck and have to fight the dealer to fix the issues. Might be wrong but will be pessimistic for this product too.

1 hour ago, Enigma_RL said:

That being said this is only my second image ever taken in astrophotography so still trying to get the hang of things but overall I am really pleased with the end result.

You've hit the ground running, amazing for a second try!

I would upgrade the laptop to a selfbuilt desktop PC. If assembling a PC is off the table, look into non-branded desktops. General brand name desktops are the worst moneysinks there are (HP, acer etc). Gaming PCs built by a dedicated gaming related store would be the best choice to look for less bad prebuilts.

I have an I7 6700K, decent speed 16GB DDR4 ram , GTX1080 and SSDs for storage.

Yesterday i split stacked 800 subs, 50mb each of OSC data into monochrome RGB stacks with Siril and Sirilic. Took about 3 hours and 400GB of storage, while a previous stack i did with APP in mosaic mode took maybe 6-7h for only 300 subs. Maybe siril is faster so give it a try?

Split stacking includes first calibrating as 32bit files and saving the calibrated files for later use. Then splitting the colourchannels into 4 different subs with no debayering (1R/B 2G). Then stacking those into mono RGB stacks. So the 800 subs turns into 3200 subs which are then stacked. Should give you an idea for how much faster you can get with a better PC. If you buy newer hardware it would be even faster, so definitely look into that!

I think a laser is a lot more intuitive to use for aligning the secondary-primary axis since you can see it from the back of the telescope. Or if its very off you can just look in the tube and see where the spot is in the primary.

I use a TS concenter eyepiece to center the secondary mirror straight under the focuser, then use a laser to align the 2 mirrors. Then the concenter goes back in to check how the secondary moved during the laser adjustments and re-center. Rince and repeat until its good. Once its well aligned, either the concenter or a laser can be used to check collimation very quickly. I prefer the laser for checking since its easy to do in the dark. I personally think the concenter eyepiece does everything a cheshire does but much, much better. If you plan on imaging the secondary being exactly centered below the focuser will become a critical issue, where as in visual use maybe not so much.

17 minutes ago, Rodd said:

I don’t agree. I can’t take a 30sec lum sub without blowing the frame on most nights. If I take subs of 10 seconds often they are hard to align due to few and very blurry stars due to lack of signal 

Well that i dont believe, there will always be starcores visible in any kind of condiitons. I image mostly from B6-8 type skies (depending on Moon, transparency, direction of imaging etc) exclusively with 30s subs and there are always stars. Also imaging with an 8 inch F4.2 newtonian and an OSC camera. Also, i have an in progress project where i try to image IFN from the afore mentioned conditions. At 5 hours in i can separate the IFN from the background but it is obviously very noisy and requires at least double or triple the exposure to reach a decent result. You can do the math yourself how long that would take for a hard Bortle 8 location and figure out why people dont do that. But not impossible.

Honestly i think you're trolling here. You have been given evidence left and right and it just seems that you want to move the goalposts so outrageously to your favour that nobody can actually prove their point to you. I mean you can see extremely faint signal in your own profile picture (assuming you took it yourself) that would be impossible from your arguments.

17 minutes ago, Rodd said:

Show me ifn taken from bortle 8/9 using lum filter. That is all the convincing I will need

Why dont you try taking a picture like that yourself? Nothing impossible about that, just takes very long to get the SNR of the faint IFN to produce a nice looking image.

Narrowband filters dont really work on galaxies, unless youre trying to capture H-alpha and mix that with normal OSC/RGB data in the end. You cannot colourbalance a galaxy to look natural with most of the spectrum missing.

I would suggest using the duoband filter for its intended targets (emission nebulae) and shooting galaxies with no filter or just a UV/IR filter.

Had a quick look at the 93% Moon with my new Pentax XW10 tonight. Nicely fills most of the field of view and is very sharp everywhere. Really center to edge good stuff 👍. Works well with my VX8 reduced to F4.2.

Unfortunately, also saw my secondary mirror. I guess its really not that surprising on a blindingly bright almost full Moon. Not terrible but maybe slightly annoying at first. Maybe try a ND Moon filter next time?

Doing a bit of imaging at the moment and the extra spike is missing as it usually is. Nothing has changed since the last time in terms of optics, i have in fact not even collimated since then. Well i did shuffle a few spacers around but not important IMO.

Very similar conditions too, around -14, but this time the entire setup was cooled to ambient well before starting as i had my gear at work in my car ready to go if the forecast was true. Could be temperature related? Not enough info yet.

57 minutes ago, markse68 said:

What is the degree order setting in background extraction for? Does increasing this make it better for non linear background removal?

1: linear as in corner to corner straight simple gradient

2: more complex, maybe from 2 different directions (moon left LP down for example)

3 and 4: LP in several different directions, maybe light leaks etc. All my work takes level 3 or 4.

I find its really dependant on the sampler placement. If the gradient is very nuked you may have to treat the lit corner as "signal" and not sample as background. Sometimes i cant make it work fully and finish with GradientXterminator in PS though.

I have 9 sessions and 16 hours of exposure since late April. Takes a special kind of crazy to do astronomy in Finland it seems. But you guys might have it worse still so ill take what i can 😀

24 minutes ago, drjolo said:

Not really, I have used EQ6-R with telephoto lens and Canon 550D several times, like this 40x3 minutes:

However for such light load even single 5kg counterweight may be too much. 

Would that lead to balance issues? But then again if the scope is so light as to be unbalanceable i doubt the mount cares since its so light.

Matching darks are necessary, if you plan on using darks at all so a set of darks for every different exposure time. Bias, flats and darkflats are ISO/gain/temperature dependent so you can use them with all the different exposure times.

In Deepskystacker you can use the "groups" function at the bottom to separate the different exposures into their own groups. Drop set1 of frames to group 0, set 2 to group1 etc. This is also used for projects spanning several nights, each night in its own group. DSS stacks all of them together in the final image.

Different stacking combination methods for the lights can also have an effect. You can try using the entropy weighted method if the exposure times were very different, like 2s x300 + 120s x 100. But generally stack as you normally would, with median kappa-sigma.

In Siril with using Sirilic you can also create a project with multiple sessions and drop the different sets into those.

Just now, ONIKKINEN said:

From FLO, on the ZWO 533MC product page:

Not the same sensor at all, but this smaller sensor is suspiciously similar in specs to the bigger 2600MC (which has the IMX571) so it might not be such a wild guess to say it would be similar. Could very well be that the 533 is just a smaller size version of the 571 with similar tech behind the curtains.

Actually here is the 2600MC, with the IMX571 from ZWOs website (cant believe i missed this somehow):