cotak

When the wife complains, yes there is some I guess annoyance. Regret? Not making it bigger. Although again the wife was already only just ok with the idea. And giant drawer sliders that were easily available and reasonably priced can only carry about 400lb a pair. With snow loads potential can't go too big. Now if I had gotten some industrial stuff could have used similar design and built a 10x10 :). But then a regular ROR would've been more cost effective vs 1k plus per pair of sliders.

Used mesu is a mythical creature over here in Canada. So few owners likely wouldn't be much cheaper. Thanks to our crazy shipping costs.

I don't think think there is anything wrong with using services like itelescope. There are uses for services like them outside of amateur imagers who are out for a picture. Schools for examples could use a service like that and it would be more cost effective than having a scope on site. And not everyone has local folks who can do out reach. And of course kids can't all stay up late. Another thing is if your situation doesn't allow you to travel for imaging, you can still get snaps of the southern skies.

He goes to larger image scale when he's doing DSO. One of the secrets to DSO is keeping your image scale ambition in check.

Led lights are worrying but I have also noticed they tend to be better designed not to splash so much light around.

A while back I found this astrobin https://www.astrobin.com/users/sky-watcher/ Now he's rocking a 10" steel Quattro. Not that everyone will be able to do this successfully but it shows what can be done by some.

The color balance is quite easy to achieve with the right app, and in this case APP (astro pixel processor) was how I managed to get better colors out of my images. And it was as easy as drawing a few boxes to select stars to calibrated against and moving a few sliders to set the correct green v magenta balance. As for noise, well each person's preference is different but I find it best not to dwell too long on it. Most of the time no one views the images at full size. If noise really bugs you I find printing really dials down your ability to see the noise

The RC scopes out there are a bit hit and miss when it comes to collimation. A edgehd 8 will likely fit your needs quite well and you can also do planetary nebulae as well. I shoot only OSC you can see my galaxies etc here: http://www.astrobin.com/users/gotak/ I am located at the edge of Toronto so LP while better than downtown is a constant problem. I use a LP filter to cut the sodium lights but locally more street lights are moving to LEDs which might be a problem. There could be some use of narrowband for galaxies in the form of highlighting Ha regions but I find my cooled CMOS catches the Ha sufficiently well to show them up.

Luckily for me one of my neighbor works from home everyday. While the ones backing up to my lot is a big family and the grand parents are always working in their yard. Still it's north of 5000 GBP in the dodgy looking shed I rationalize it by saying well... it would be an opportunity to get approval for an upgrade! Still would suck but that's the silver lining.

Or a big silica gel pack, one of those you can recharge by plugging in. I use two for the scope and mount in my observatory, but which are kept under a big mattress bag. The silica gel drops the humidity below 20%.

Trod on toes literally (ouch!), or as in people didn't know how to use it right at first, or as in it ruffled some feathers on fans of established expensive brands?

Yes all surface mounted stuff is modifiable. Although one time we did that at work to make a special dimm and the PCB got so soft it was like a fruit roll up

Ok so it looks like the most likely candidate for my south pointing issues is.... Balance. Turns out my OTA being heavier on one side, while balanced in DEC, causes problems for the RA when it's pointed south, resulting in a west heavy situation. Also my dec was less balanced than I had thought as the weight bias means it felt more balanced then in reality. So next step is to make an offset counter weight for the OTA and see if that fixes the issues I saw with guiding.

These setting seems to work well: Both axis using hysteresis. Seems reasonable level of aggression and 4 or more second exposure results is very smooth trace. East of pier when pointed south is a pile of doodoo still, wondering if that's cause I am looking over a line of roofs and seeing thermals. As: See the big house there right behind with the grey roof, that's directly south. And south is also downtown Toronto.

So last night was a bit of a cluster (expletive). I did not end up trying out PPEC but was trying different settings in hysteresis. I am suspecting there's something wrong with my edgehd 8. So here's what it does: Target is high in the skies so scope is almost vertical (FYI was specifically chasing down this vertical issue as saw it with other targets), when on west of pier mount does Ok and guides well with some random movements here and there which I think are mirror movements but overall controllable. However, no matter how good the graph is there's elongation in the stars. On the east side the graph has random 2" spikes and again the stars are elongated slightly. Now the star gets better later on when the scope's tracked so the OTA is less vertical, this I also saw in a previous session. So that was a hint there. Previously while talking to iOptron about this I got a beta firmware (now the official April 2019 one) and wanted to test. During that run I didn't see spikes in the guide graph but I didn't take any images. So yesterday night when I saw the issues again with east of pier I manually slewed to a lower DEC and there it was again, no spikes. Took a quick 3 minute sub and stars looks pretty good. Switched to sharpcap and took a look at what the main camera was seeing live (at around 5fps as I was on USB2) and other than the star moving around due to seeing there was no hints of RA movements or DEC movements. Can it still be the mount or encoders? Well actually unlikely because this elongation even with great guiding was also seen before on my ieq45 pro when the scope was near vertical, but back then I just attributed it to So it seems I have elongation in stars from something to do with the optics when vertical and seemingly also some sort of mirror shifting, but before everyone scream mirror flop it doesn't look like other examples of mirror flop I have seen and refocusing correctly doesn't solve it. Overall not the most enjoyable of night and now I wonder if I should consider replacing the edge with something more rigid. Tonight's another clear one so I'll see what else I can dig up. Maybe I'll try for a lower target and see how that goes for one night of guiding to try and confirm the above.

My skies are hopefully clear Thursday night, I can give it a 15 minutes run to see. The posts by Gaston on CN is interesting. I think it is over simplified but there are interesting points to consider. I'll see if a zero or low min mo, long exposure and low aggression is better.

You mentioned ieq45, actually very similar but without the electronic balancing. You could say the the ieq45 was widely seen as an attempt at imitation.

https://groups.yahoo.com/neo/groups/ap-gto/conversations/messages/66163 Watch out you don't damage your worm. Everyone knows iOptron CEMs have this risk. Seems one needs to be careful too with a mach1 or risk damaging the worm.

Right. I haven't seen as high as 0.7 on RA yet. Mostly mine comes in max at 0.55 on RA at this point. The problem is when the guiding appears to over correct. I am trying to see if longer guide exposures will help reduce this issue. I also am seeing when the scope's pointing generally straight up some issues with larger deviations when scope's on east side of pier. When the it's pointing lower in DEC it seems to have no issue, so it could be just my mirror but it does this for a a long time with some period of quiet so I am not entirely sure what the cause it. The other suspect is off balance RA which I'll have to do some experiments to chase down.

Hi Chris This is what the frequency plot of my copy on a good night looks like: Not much PE to manage with PPEC. I would worry that PPEC would end up chasing ghosts but it might be worth a try. My guiding last night was pretty bad when I tried hysteresis, Z and lowpass 2. I suspect that a few things (To be confirmed) to be important to this mount to work well. While hysteresis worked well previously last night it seems all the algorithm struggled with what I think was a combination of winds and bad seeing (it was still gusting to 20-30 kph when I started and all night the winds never dropped much below 20 kph). Next time my attempt will involve potentially improving my alignment in hope of making the guiding task as easy as possible. And I'll see what happens with a truly long exposure like 10s. Finally, all the noise online about SDE and I wasn't seeing much of anything in my guide trace. So to recap supposedly the period of this "fast" oscillation in the CEM60EC is 5-6 seconds or a 54 fundamental. Often touted as caused by cheap encoder in iOptron mount, but don't believe everything you read online. Does it exist in a gen2 CEM60EC? Yes, but... It's less than 0.3 p-p in amplitude. I am not sure why I got two peaks, it could be due to the short data set. However, it is within the range of measured SDE in the CEM120EC. Personally, I don't see any impacts at 0.54" imaging scale with a 1400mm focal length. So for all intent and purpose it's a non-issue. What is SDE? Well it's the error that results from interpolation between encoder ticks, as it is very expensive and technically challenging to have sufficient native encoder resolution to avoid this. Even the often worshiped absolute encoders use interpolation to achieve sufficient resolution. And it's not like interpolation is a super wild guess, the interpolation essentially process the analog signal from the reader to get additional information not available if you treat the signal as digital pulses. The problem occurs if you have alignment errors between the encoder and the reader head , and not as far as facts are concerned (as often stated without proof online) due to the lower cost of incremental encoders (plane wave used incremental as well). As absolute encoders are perfectly capable of having SDE as well. Possible solution to mitigate alignment error (which are in many ways unavoidable) are dual read heads (I know even AP only use one) or software solution to record and compensate for the error. There are some users who have measured AP encoder mounts and say no SDE, which sound good, until you see the noise floor is above the 0.3" range in that measurement and so if they do have similar amplitude SDE (and it would be a non-issue due to the low amplitude) you wouldn't see it with a very high noise floor. At the end of the day if your fast errors are all of 0.3" every 5 seconds or so and you are seeing limited you will be hard pressed to find it showing up in your images.

I'd like to offer a opposite view towards the suggestion to go with some really high end stuff. There is a lot of reverence for the expensive mounts online. And they are often touted as the solution to the mount issues that ills. However, before one decides that it is their best choice one should think a bit more about what you are trying to achieve and how much you ultimately want to spend. There's nothing great about buying a hocking big mount then having only enough for a modest scope. This isn't unheard of, there are people out there with really great mounts who don't come near their states capacity and go around telling everyone to buy one. Now I am not saying there are zero benefits from going for a better mount but the rewards has to be weighted. What I am trying to say is that there are lots of internet wisdom which are really designed for the lowest common denominator, and doesn't apply in all cases. The biggest reason for getting expensive stuff is that lower cost one is going to be hard to use. It's not entirely untrue this idea. For me this idea is 1) over stressed online, 2) Bit out of date and 3) Often stated as someone's experience in a vacuum. This line gets repeated over and over and after a while many just automatically parrot it without thinking. It is very much true a while back when mounts came with black tar for grease and there are no periodic error specs for reasonably priced mounts, today both of those problems are history. Finally, when someone says that they had a hard time with a lower end mount and an expensive one solved all their issues: Well how much skills they did they gained using the cheap one? Did they started off with the known problem child (applogies for those who like the AVX) like the AVX? Also, what a lot of people don't say is they got an expensive mount to fight the wind. Yes that is often the one most common reason why someone gets a massive thing and put something tiny on it. Odd choice if all they do is image from their backyards as often building an observatory cost less. BTW there are exactly zero brands that has no problems. There are many people asking for help online for AP, Bisque, Avalon etc. And there are people who have sold off all of those brands because they found the problems they face are too great for the cost of the mounts. And this shouldn't be surprising nothing's perfect. There are a lot of factors to consider when ti comes to mount performance. Model, focal length of scope, moment arm of scope, imaging scale etc. And what works and doesn't for each person sometimes seems like a mystery but often the reason is hidden in the specifics of the use case. And this applies to any mount so it is not entirely correct to just say pay more and it'll work, it might not due to many reasons. The ones people recommended such as EQ6 etc are in the mid price ranges and they are used successfully by many people making images I am silently a bit jealous of. They are already really quite good and often people put what for many are end game scopes on them. So before going off and buying the high end stuff consider if you really need it and whether a modest first step could be a better choice.

So a while back I posted this in another thread: This is just me writing up what I have found with the CEM60EC so that others can reference it later on. I find that hysteresis works the best it seems. The other more advanced algorithm tend to be attempts at stopping overreaction to seeing or transient events, which might be good if you are using a fast guide exposure and have a normal mount. I find with the encoders those ends up reacting later than necessary. I guess that make sense if you consider that my copy has p-p PE of about 1" (note this isn't normal PE but a measure of the transient spikes of an encoder mount) and RMS is about 0.2-0.3". There is just so little to correct for that if you have good PA, sufficiently long exposures to avoid chasing seeing, all you are left with is PA drift or imaging chain shifts to compensate for. So what I find is 80-95% aggression, 0 hysteresis and a minmo just slightly above the remnant seeing effects works best. PA becomes quite important with encoder mounts, with it off you'll find the mount tends to end up on one side of the guide graph while Phd keep trying to bring it back to alignment. I find it is much more sensitive than regular mounts. Originally I though the new Z algorithm would be ideal as it only correct for long term events. I didn't find it work too well maybe due to no control on aggression. However, it might be that I haven't gotten used to it yet.

Should consider 18 plus Kg mounts. For relatively future proof for most people you can consider: - EQ6 Pro - CEM40 - CEM60 If budget is an issue I'd suggest a CEM25p as a starter mount. Meade don't usually make most people's list.

He wants to makes us an interstellar species, he should do it, schedule regular sky surveys and make the data free for all. Could help prevent reenactment of the KT event by having 12,000 scopes making essentially our first always on space sensor network.

You need to store them in a dry box in Hong Kong. Almost everyone with camera kit in HK use dry boxes. For scope a dry box that big would be kind of expensive but you can make do with any sealable box and some silica gel packs. Or you'll get the fungus again.