nothing i try has worked and nothing is narrowing it down. i think a large part of the problem i have is just horrible seeing and that is messing up things. i mentioned before that i tried to do some planetary imaging and it was just not worth it, jupiter was a blob, i could see europa dancing around like crazy on the screen when i was shooting at high frame rate, an issue i am pretty sure was due to just atrocious seeing. i have tried rebalancing, i have tried testign on a still night and no matter what i do i cant train the PE out of the mount. i consistently record a PE of around 5-6 arc seconds, the chart looks really consistent and like it should correct out, i save the curve to my mount and apply PE and it makes things worse. i have tried inverting the curve too just in case but no luck... i am thinking that i just shouldn't do a PEC, though i would like to get the best possible tracking out of the mount.
I can feel your frustration!! Been there big time when I first got my MX (original model). I could NEVER get TSX to work. Period. There was a bug that SB wouldn't admit to. Finally they "fixed" it but it still never worked for me though others in the Southern Hemisphere claim it works. It always worked with PEMpro and I continue to use PEMpro to this day with my MEII.
So, were your most recent tests with PEMPro or TSX or both? If you tried with both have you tried comparing the two correction curves. They ought to look very similar (I'm talking about the actual curve you paste into the Bisque TCS. If they look really different that might provide some sort of clue.
I think you wrote in a previous thread that you did try the slew tests....moving a few arc-sec back and forth and you saw zero backlash. Is that correct? I'm not sure if BL in RA would prevent PEC from working. I think it wouldn't since the motion is always in the same direction....just faster or slower (no reversal as in DEC corrections).
You have now clearly run many PEC measurements over many different nights, some in better or worse seeing. Do the curves look similar? They should if they are valid curves. On your latest results what is your peak to peak uncorrected value?
Peter
EDIT: Can you post a picture of your correction curves? One made by TSX and saved to the mount and another of the curve generated by PEMpro and saved to the mount?
Hi Aidan, if you are not using it, I think you need to use Pempro. I had the same results using the SkyX PEC and it never worked. I used Pempro and it was sorted in an hour or so.
Hi Aidan, if you are not using it, I think you need to use Pempro. I had the same results using the SkyX PEC and it never worked. I used Pempro and it was sorted in an hour or so.
Hi Paul, i have tried TSX and PEMpro v3 beta. i ran pempro for over an hour and each time it laid down a really consistent PE curve. you would think that it should correct out really well. when i compute the curve and save it to the mount, it definitely makes a change to the tracking so it is doing something, but just makes it worse. i think i will either create a video or do some screen shots of the process to see if someone can point out if i am doing something really stupid (the most likely cause)
Quote:
Originally Posted by PRejto
Hi Aidan,
I can feel your frustration!! Been there big time when I first got my MX (original model). I could NEVER get TSX to work. Period. There was a bug that SB wouldn't admit to. Finally they "fixed" it but it still never worked for me though others in the Southern Hemisphere claim it works. It always worked with PEMpro and I continue to use PEMpro to this day with my MEII.
So, were your most recent tests with PEMPro or TSX or both? If you tried with both have you tried comparing the two correction curves. They ought to look very similar (I'm talking about the actual curve you paste into the Bisque TCS. If they look really different that might provide some sort of clue.
I think you wrote in a previous thread that you did try the slew tests....moving a few arc-sec back and forth and you saw zero backlash. Is that correct? I'm not sure if BL in RA would prevent PEC from working. I think it wouldn't since the motion is always in the same direction....just faster or slower (no reversal as in DEC corrections).
You have now clearly run many PEC measurements over many different nihts, some in better or worse seeing. Do the curves look similar. They should if they are valid curves. On your latest results what is your peak to peak uncorrected value?
Peter
Hi Peter
i haven't done a direct comparison from TSX or pempro curves, i will load them individually tonight and have a look. from memory they are pretty similar but it looks like the TSX one is more complicated.
i haven't done the BL test, i will do that tonight as well. I made the adjustments to my guide camera so that it is aligned to the RA axis.
i just wonder whether the horrible seeing is causing the issue. perhaps there is a boundary layer on the mirror causing issues with that, i have tended to run the fans permanently to try and keep the mirror close to ambient ...
I just went back and looked at some of the old curves i created, and i thought i would share it here to see if it sheds any light on the issue.
pic 1. is an image of the PE curve created by running TSX
pic 2 (red line) is the PE curve run by pempro
pic 3 (red line) is the PemPro PE curve just inverted, it seems to fit better to the TSX one
pic 4 (red line) is a PE curve i collected through PemPro on an earlier night.
Pic 3 and Pic 4 look very similar just phase shifted, i wonder if the cycles are not synced properly
hope you don't mind a nonPMXer butting in, but I guess I can't do any damage..
FWIW, looks to me like the two softwares show the same pattern, but PEMPRO is using a different (wrong) timebase (it is only showing 1/2 the cycle) and TSX is possibly using an optimistic conversion of pixel error to arc sec (results in it displaying roughly half the actual error?). That might suggest a very thorough going over the setting for the two programs to get the same timebases, focal lengths, pixel sizes etc. and ensure that dec correction is on in TSX (actually, come to think of it, that could be one place where they might have issue getting the correction right for the southern hemisphere). Again FWIW, maybe put aside TSX and try getting PEMPRO to generate full length PE cycles (that is if it isn't doing so now).
hope you don't mind a nonPMXer butting in, but I guess I can't do any damage..
FWIW, looks to me like the two softwares show the same pattern, but PEMPRO is using a different (wrong) timebase (it is only showing 1/2 the cycle) and TSX is possibly using an optimistic conversion of pixel error to arc sec (results in it displaying roughly half the actual error?). That might suggest a very thorough going over the setting for the two programs to get the same timebases, focal lengths, pixel sizes etc. and ensure that dec correction is on in TSX (actually, come to think of it, that could be one place where they might have issue getting the correction right for the southern hemisphere). Again FWIW, maybe put aside TSX and try getting PEMPRO to generate full length PE cycles (that is if it isn't doing so now).
you might be onto something there Ray ... let me look into it a bit more, i am not sure why it would be doing that
during my lunch break i reloaded the PEC data into PemPro and took a screen shot. so it looks like the data is appropriately collected with the right worm cycle, but something has happened when that data was transposed into TSX, it only took half the cycle and assumed it was the full cycle i cant immediately see a reason why this would be the case.
i just wanted to see how this would affect things, i took the data and just removed every second point through excel and then pasted it into the PEC module in TSX and this is what i got. the curve aligned with the TSX one, but it is the wrong scale. in PemPro, it says the error is +3.4 / -2.8 but when it comes in to TSX it is -6.7 / + 5.4
the image scale does say the correct figure in PemPro 0.465 arc seconds per pixel ...
When you used PEMpro, after you collected data on the analysis page what does the graph there say about your peak to peak error? Is this error the same value that you see when pasted into the Bisque TCS? Similar to running PEC in TSX? (Sorry! I missed your post above). It's really curious how you got the curves to align by removing 50% of the points. I'm not sure at all what that means.
I take it that before using PEMpro you went through the mount wizard where you measure the star trail lengths, etc? Then on the first page of the mount/camera settings page you synched the worm period before collecting the data?
I wanted to check on your assertion that the worm periods are the same for the MX and MX+. I found this so that is not the issue (I had a bit of a doubt remaining):
ME and ME II: 576 cycles in 24h → 2m30s of sidereal time
MX and MX+: 375 → 3m50.4s
MYT: 320 → 4m30s
I'm not remembering if this was previously suggested (and I know your scope is remote!) but perhaps you could eliminate some of your concerns re seeing/large aperture by mounting a smaller scope (a refractor?) and guide camera perhaps on top of the RC and measuring PEC. In any case you would have a point of comparison. Either way the results should be very similar.
Another random thought, perhaps for your seeing .45 arc-sec is asking too much. You might try binning 2x2 which still puts you below 1 arc-sec. I also notice that your exposures were around 3 sec. I think you can do better if binned. Try 1 sec.
Finally, if you can't figure out why only 50% of the curve from PEMpro ends up pasted into the Bisque TCS (and why the Peak to Peak vale changes so much) by all means post the question at Ray's forum at CCDWare. He always has answered me quite quickly!
yeah i ran the wizard, synced the worm cycle. the issue happens when it is copied to TSX. PEMPro comes up with a curve that looks right but it gets screwed up when i copy and paste it into TSX. Maybe we could meet up given that we are both in Sydney and i can step you through what i am doing. there might be something really obvious.
Yeah I have, I am using a ml8300 with a fl of 2,467 mm
I don't know either Pempro or SkyX, so please forgive this question if it is a silly one. Are you using the 8300 to gather the PE data? In the EQMOD world, PE data comes from the guide camera and the guide image scale is the one that is used - although I suppose there is no reason why the main camera could not be used.
I don't know either Pempro or SkyX, so please forgive this question if it is a silly one. Are you using the 8300 to gather the PE data? In the EQMOD world, PE data comes from the guide camera and the guide image scale is the one that is used - although I suppose there is no reason why the main camera could not be used.
the suggestion from TSX is to use the main imaging camera, i have used that for both PemPro and TSX capturing
The other day, at lunch you said, you pasted the PEMpro data into the Bisque TCS. Simple question, were you at that time connected to the mount? Did you save to the mount and then retrieve the data?
If not, I believe TSX will possibly default to the ME where the worm period is about half that of the MX+. Maybe that is why you see only half the curve?
Peter
PS Maybe next clear night I could remote into your imaging computer via Team viewer and watch you run through things. Just an idea. Late is better than early. Feel free to contact me by email and we can exchange tel #s. (prejto at oberlin.edu)
so it looks like there is an error in PemPro v3, Ray is fixing this up and should have a new version soon. i am looking forward to seeing whether this resolves my issue completely
just another cry by me, the seeing looks good but i am still getting major errors in RA. this was taken while imaging M16 so not near the pole. i am trying to get the PEC working, the new version of PemPro keeps crashing on me. might give it another go tomorrow.
