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    SGL 2017 SP

Olsin

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About Olsin

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    Nebula
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    Jutland, Denmark
  1. Chuckles ... I've just deleted a long winded explanation explaining why i did what i did, how i did what i did and the circumstances i was working under but at the end of the day, i'm only kidding myself. Yes i blundered. I hadn't tightened down the bolt holding the mount to base. That explains the consistently high figured align errors, despite all other parameters being on track. As soon as i read that line in your post, i remembered that i had only tightened it sufficiently to hold the mount while i attached the leg plate. I didn't get back to it. Visually observing the play on screen in the alt/az bolts lead me to conclude 2+2=3. The good thing is though, i now know the whole handset routine pretty well. With clear skies forecast for this evening/night i'm now itching to put it all together and see if i can't achieve a decent PA and star alignment. Thank you everybody for your help and encouragement.
  2. After 4 complete routine run through's last night i've given up trying to get my AVX accurate. I think i've been unlucky and brought the worst one of the batch. I've also located the problem which is the altitude knobs. On top of the 4 run through's i tried an ASPA and got the star dead on. I then unsynced and immediately ran through another ASPA on an adjacent star. It should have been spot on considering the mount had just been polar aligned but it was half way across the FOV..hm, I finished the routine and again tried another ASPA on another star. Again it was way out!. I think the problem is tensions in the alt bolts, there is to much play in them. Trying to tighten them just introduces movement on the az axis....loosening and redoing the az axis also affects the alt axis. It takes a long time to align the star dead center and often i have to settle for one of the axis's (or both) not being absolutely tightened right down. I have to compromise if i want a dead center alignment. As soon as i slew the mount again it seems to release small tensions in the alt/az knobs. I noticed to that the merest brush against the weight bar was also enough to knocked it out of alignment. I'm a bit saddened by the realisation that i may have brought a lemon, especially considering the amount it cost ... a definite under the belt blow to my enthusiasm. So yes, 4 complete run through's and every run through was double minutes out of alignment when checked! I have been as precise as i can at every step of the set up, i can't do it any better than that. You can't make something more level than level, you can't point it more north than north. Double checking and then re-checking every entry into the handset and spending time to precisely get the alignment stars to end dead middle of viewfinder using the correct down and right buttons on the handset to finish off. Ok...writing that down helped a bit. There's still enthusiasm there. I guess a polemaster won't help that much if the mount itself can't stay where it's put. Would a guide scope/cam/PHD be able to soak up those inaccuracies?
  3. Now that's the sort of honest opinion i was looking for when i first started this thread. All things being equal, just what is the AVX capable of? I don't really want to keep wasting my time chasing accuracy if that accuracy is not to be had. I've already considered polemaster and a guide scope/cam configuration but that would just be introducing even more complexity into an already challenging exercise. I'll go that route if i have to, however if the AVX is capable of comfortably giving 60-90 second subs though a manual alignment and maybe a touch more if i perfected drift aligning, then i'd certainly be happy with that for now.
  4. @ Peter .. I rebooted the mount simply because i've read a few places that rebooting and doing another 2+4 should be better than unsyncing through the handset and re-aligning ... although it's all still very new to me. I don't know if one way is actually better than the other. However, now that i can read what is scrolling across the screen on my handset (which in turn now makes the manual much easier to follow), i'm sure it's only a matter of time before i've settled into a good routine.
  5. Thanks MathMog, as i mentioned before i use my DSLR for centering. It has a flip out and turn around live view screen that can have a grid projected on it. The grid intersects in the middle of screen giving me cross hairs. I can zoom in on the star and get it absolutely dead on. However you are correct, I don't use the zoom in feature everytime, inaccuracies could be creeping in there. I'll tighten up my act and see if i can improve those align numbers. I've read posts of people saying they get 90 sec subs just by doing a 2+4 then ASPA and another 2+4. I can see i've got a way to go before i can match that. @Filroden .. No i didn't check PA alignment there, i went straight into the ASPA routine. I realise it shouldn't be necessary to do both analogue and ASPA but i wanted to see if they matched up. My thoughts were that if ASPS slewed right back on the star and there was no need to adjust then the analogue PA routine would suffice in the future. I should have done it the way you mentioned though. My way leaves me in doubt as to which of the 2 routines was inaccurate. I'm none the wiser. So yes, maybe i should concentrate on one method. ASPA and drift you say. I'll have to look into that. @newbie alert .. Hm, no, what i done was powered down (leaving the scope pointing at Arcturus i think) and then manually reset the mount to the index position before powering up again. I didn't select goto home on the handset and i didn't set home position before i started. I've somehow changed my default home setting position and can't get it back. When i first got the mount, selecting goto home on the handset would send it back to the index position. Then i accidentally clicked "set" one night when i meant to select "goto home". Since then the mount doesn't associate home with the index position. I've tried restoring factory defaults but it doesn't change anything. If i want it to goto the home/index position now i have to set it at power up and then reset it if i power down and power up again. Are you then saying that by manually setting the mount to the index position after i powered down, i ruined my alignment?
  6. Cheers guys ... I've now tried the new power supply and adjusted the scrolling text settings on the handset. Now i can read what it says. Strange that by default it should be set so high. So i started out by levelling the base. Once done i attached the mount, tube and other bits and bobs and balanced it out. Using my polar scope and the app "Polar Align" i PA'd the mount spot on - i aligned the polar scope to the mount a few days ago. I then powered up and entered all correct parameters and selected 2 star alignment. The 1st star, Capella was about half a tubes (8") width from the edge of my FOV. Does this mean, despite being careful and thorough with the initial levelling, PA and entering of parameters, i hadn't been accurate enough? The next star was a bit closer and the last 2 remaining stars of a complete 2+4 alignment, were both almost spot on. I then slewed to Denebola and started the ASPA. I could now read what was on screen and simply followed the instructions. It was a bit tricky using the altitude nob's to get Denebola smack on as tightening them introduced small movement in the other axis. I have replaced the large bolt that sits under the polar scope with a smaller one so that i can use the polar scope. The tip of that bolt is not as round as the default one so i suspect that's introducing inaccuracies. Still, after a lot of messing about i got it tightened down with Denebola dead on the cross hairs and finished the procedure. Powered down, set to index and powered up again. Same run through using 2+4 and display align showed .. alt 3min 32sec, az 2min 27sec. I understand that's not a particularly good alignment although i don't know how i could have been more accurate during setup and alignment. Although cloud came in ended the session, if instead of selecting display alignment i had done another ASPA, powered down and 2+4 calibration, (so, 2+4 + ASPA + 2+4 + ASPA + 2+4) should i have expected to see the accuracy increase?
  7. Yes thanks MathMog. I think that is exactly the problem i had. I've tried running through the manual and this checklist as well as another technique where you select identify and enter on the handset and then press undo before it slews to the star. There is no undo on my handset so i assumed "back" was the same although pressing back while it was slewing to the star done nothing, it carried on slewing. So yes, there seems to be small discrepancies in the various descriptions that cause confusion ... especially when you don't really know what you are doing. There is a more than a good chance i incorrectly pressed enter when i should have pressed align or vice versa. Enter and Align are both 5 letter words and hard for me to tell the difference when mixed and blended with other words that scroll across the screen in soft shades of red. Still, between you and Peter i think i now know just what i have to do. Now i just need the new power supply (hopefully tomorrow) and clear skies to try it out. @newbie alert. I was going to PA on Regulus but could see some kind of flashing warning but couldn't read what it said. So i chickened out and pressed back and manually slewed to Arcturus instead. I got the flashing warning again and again hit back. So i manually slewed to Denebola and got the same warning again...I kept thinking i had done something wrong so i'd power down and power up again and restart right from scratch. So yes...going to have to look in the settings and see how i can change that scrolling flashing text.
  8. I've ordered the new power supply but i was out again last night anyway even though i expected to have problems ... which i of course, did. I don't know if this is power related but i've noticed (actually noticed it the 1st time i used the handset) that the scrolling text is incredibly hard to read. The static text is plain enough but as soon as it starts scrolling across the screen, the text seems to blend together. I often don't know if it's telling me to press enter or align. There's also some kind of warning message when choosing a star to polar align on but i've never really been able to read it. Does anyone else experience hard to read scrolling text on the handset? Another strange thing is that my mount can't remember it's home position. It was by default set at the index position but i accidentally pressed "set" instead of "goto" the 1st night i was using it. If i now set the home position to the index position and select "set" it only remembers while the mount is powered up. I've tried returning to factory settings but it doesn't associate the index position as home position by default anymore. I updated the firmware about 2 weeks ago. @Peter ... I'm still having trouble with the ASPA procedure. Small discrepancies that make it slightly confusing.. Polar Alignment Slew to bright star high and near meridian.(not overhead) ... Check Press Align – Polar Align – Align Mount. ... It's here i see some kind of warning scrolling across the screen but i cant' really understand what it says Scope will slew away and back. ... it only does that after i've pressed Enter in response to the scrolling message Centre star in finder – Enter – centre star in EP. Scope will sync. ... I understand this as you mean center star in the finder scope using the handset controls and then press enter and then center it in the EP again using the handset controls and again press enter? Enter – Use Lat and AZ bolts to centre star – Enter ... but the star is already centered in the EP from the previous steps? Updating Star Alignment Press Align – Undo sync – Enter Slew to one of the original alignment stars. Press Align – alignment stars – select star. Centre star – Enter- Align. Repeat for other Alignment star. Slew to bright star on opposite side of Meridian. Press Align – Calib stars – Enter. Centre star – Enter – Align. Press Back – Align – Polar Align – Display Align. (this will show your actual PA error) EDIT: ... Yes, sorry. I have a 8" sct. The standard 25mm EP i got with the scope Has a tighter FOV than my camera use in prime focus with the telescope. I use the camera for aligning because it gives correct orientated pictures and only allows the brightest stars to be seen on live view cutting out distractions. It also allows me to zoom in with a grid pattern on screen to get dead accurate middle of the screen precision.
  9. So here's the results of the nights attempts. I started out using the daylight to align the polar scope to the mount (a time consuming frustrating exercise) and was happy with the end result. The cross-hairs didn't move a nano when moved back and forth through 180 degrees. As soon as i could spy Polaris i used the polar align iPhone app to find it's position in relation to the NCP and adjusted the mount until it was absolutely spot on. Then i started the 2 star alignment, first on Capella and then on Regulus. The 2nd calibration star was surprisingly close to the scopes FOV. The remaining 2 (4 in all) calibration stars were all within the FOV after the scope slewed to them. Brilliant! ASAP was done on Arcturus and my align success showed 00,00,32 on one axis (i didn't jot that down!) and 00,01,01 on the other, so about a half arc minute difference between the 2 axis's. I know i should have powered down and redone the setup but i was eager just to see what this kind of accuracy could produce. I selected M51 on the handset and slewed to it. I see nothing on my camera monitor so i took a 30 sec/iso 800 sub and was impressed by the result. It was probably the best picture i have produced to date (i still had to crank up the exposure in PS to see any detail though). M51 just slightly right of center. I then tried a 60 sec sub but this showed terrible star trails. Back to 45 sec and a slight improvement on the 30 with only very small star trails. Instead of redoing the setup i ended up swapping the camera for an EP and spent the next few hours just looking around although both tracking and goto quickly became unreliable. I'm assuming this was because i didn't redo the alignment. Another thing i noticed was that i could be zeroed in on a star. The star would move around within the FOV and then stop, remain static for 15-30 seconds (sometime much longer though) and then start moving about again. I put the camera back on (i can see bright stars on the monitor) so that i better could see the movement pattern but there wasn't really any. The stars just kind of wiggled around with varying speed without favouring any particular direction. Then the star seemed to settle down and it'd be quite motionless within the FOV. I selected goto Jupiter and it didn't end up in the FOV. I could see it in my finderscope so it wasn't totally misplaced. I slewed to it and watched as it slowly drifted of the screen. I used the handset to re-center it and this time it started to move away but stopped and then stayed reasonably still for maybe 10 minutes until i slewed away to Vega! I would have thought an inaccuracy in precision would be consistent. I don't understand how the mount can intermittently produce good results while showing obvious precision errors? Could it simply be a combination of small alignment error + low fluctuating power supply or is it systematic to mount error? Would it also be normal to assume that even an initially well aligned polar/star unguided setup would lose precision with time? Clear skies again tonight, so i'll of course be trying it all again. This time i will do the routine 2 times and make a proper note of mount error. I finished on Vega last night. After just looking at and around it through an EP, i put my DSLR back on and took a quick 20 sec sub. I know you guys can see a ton of problems with this picture and i'm sure i will to one day ... but for now, this is probably the best astro pic i've produced to date. @MathMog .. Actually i'm english. I just live here @Peter .. I've seen quite a few video's on YouTube demonstrating and explaining the polemaster. No doubt i to will go that way too sooner or later. It definitely looks like a good bit of kit.
  10. Thanks Peter. I've printed your checklist and i'll try that routine if my attempt at PA first with PS then 2+4 star alignment doesn't pan out. Decent of you supply the link. And thank you to MathMog. I was looking at a 5ah power supply on Teleskop Ekspress. That stands at approx 500kr, yours at only 150kr. Not only did you explain why doubling up the routine improves accuracy, you also saved me 350kr. Tak for det du.. @newbie alert ... And yet another routine. Crikey, i didn't realise there was so many ways of achieving good results. Thanks a lot for your input.
  11. Thanks Gazabone ... You know, i have read a few other places that some avx users also have reached the same conclusion with regards to power supply. This has made me doubt my own source. I don't have a power tank and use a 12v ac adapter rated at 3A. From the moment i clicked on "buy" i've been wondering if i should have paid the extra for a 5A rated power supply. If i can't get good tracking despite all other parameters being good then a power supply will probably be the next buy. I just don't like using any type of rechargeable battery when i have a perfectly well functioning mains outlet not more than 3 meters from where i stand my scope. Besides, from experience in other interests i know that rechargeable power tanks only have a certain shelf life before they start to drop off. Still, your test sounds worth a try. As mentioned, i don't have another power supply but i will do the test today just to see how my mount preforms with the power supply i use. Thanks for your input.
  12. Thanks MathMog. Yes, i'm sure i've entered all the time/date/location/daylight information in the correct format. The only thing that caused any head scratching was my timezone. I've never thought of the western European continent as anything other than GMT+1, so +1 was entered. It took until the next session attempt to realise Denmark, at this time is UTC+2. Due to one problem or another, i haven't actually been through the whole alignment yet. I've just noticed that the additional calibration stars don't usually end up close to the scopes FOV by the time i've got to adding let's say, the 2nd additional calibration star ... i'm sure though the problems are all my own and not the mount. I guess i just wanted to hear someone tell me, that the mount can achieve good things. However, now that i've acquired a polar scope, i'm going to use today to calibrate it to the mount and hopefully run through the whole alignment procedure tonight. I don't quite understand why you do the whole routine 2 times. It was my impression that the mount dumps all info apart from location, when you turned it off. How does it use the 1st alignment to improve the 2nd?.
  13. No no Mike, i never take offence to people trying to help me, especially when i recognise my newbie status.. I actually use the live view on my DSLR to center on stars. Only the brightest stars are visible on my display so that cuts out distractions. I also get a correct up/down L/R picture which makes using the keypad on the handset much more intuitive i feel. I turn the grid on which gives me an intersecting line smack in the middle of the display. I can then zoom in and get the star exactly in the middle. The camera is attached prime focus and it all feels solid so i assume the middle of the live view screen is just as good as the middle of an EP. As there's quite a bit of movement when zoomed in i usually try an ambush method where i line the star up and wait for it to cross the cross hairs, at which moment i immediately press align on the handset. Ok...checking the handset for PA error. Hmm, i haven't come across that yet. Thanks for the heads up. Yes, i too have read reports of people getting on very well with the AVX mount. I've also read reports of people having nothing but trouble with them. It's hard to judge in all accounts, whether it's because of intermittent quality from the producer, inherent instability with the mount or just inexperience from the user. I think a lot of it maybe inexperience as i'm certain that's the roots to my own problems. I'm hoping so. Saturday tomorrow with the clear skies from the afternoon onwards (apparently!) So i'll calibrate the polar scope tomorrow and take another crack at getting a good mount alignment and tracking...Cheers
  14. I was wondering if anyone has an idea on Celestrons AVX mounts default accuracy. For example. If the assumption that the base was 100% level, mount well aligned with a well calibrated polar scope and all handset parameters correctly entered = true, how accurate should the first selected star in a 2 star alignment be? I'm having all sorts of problems with my own mount although i'm sure they are all of my own doing. I couldn't get the 2 + 3 star alignment plus ASPA to work for me (though that maybe because i simply don't fully understand the procedure). Then i read a few posts where someone said that he don't bother with ASPA. He accurately polar aligns the mount first, then does a 2 + 4 star alignment and end of story. So i've been trying that route myself. I didn't get a polar scope with the mount so i initially tried winging it by simply aligning Polaris through the hole where the PS should be and tried to get it as close as possible by eye. Wasn't satisfactory though. I then got a polar scope and discovered i couldn't use it because of the chunky latitude bolt restricting access to the eyepiece. Quick drive (that shouldn't really have been necessary) to the DIY sorted that out ready for the promised nights clearish skies. Unfortunately i knocked the finderscope out of alignment when it was dark and wasted much of the clear skies on trying to realign the finderscope on a star although i couldn't really do it as my 8" sct doesn't allow anything in the sky to stand still. I had to wing it as best i could although it caused a lot bother. Before i could finish messing about clouds came in. I've now discovered that the polar scope also needs aligning to the mount so that's the next job. So, does anyone with an AVX mount know of their default accuracy when all parameters = true?
  15. Hi guys ... I have a question regarding star alignment using the nexstar hand control. I've been trying the 2 star alignment followed by adding at least one (have also tried 3) extra calibration star and then slewing to a named star to begin all star polar alignment. I notice the star i choose to polar align on and slew to isn't usually visible on my camera's live view. I have to manually slew to it before i can start all star polar alignment. Is the reason the 2 star alignment including additional calibration star/s is inaccurate when slewing to it's 1st named star, because the initial setup of the mount (level, pointing north at correct latitude) was also inaccurate? The whole routine starts out with setting up the mount, then 2 star alignment, then all star polar align and then back to re-align because the mount has been moved. It seems a really convoluted way of doing it. Wouldn't it be better to polar align the mount, then do a 2 star alignment plus additional calibration stars and skip the all star polar alignment? Update: Again i should have spent more time searching for an answer before posting. I think i'm learning that if there's no replies within an hour, its' because there's already a ton of material on the subject