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Everything posted by Spacehead

  1. Stable enough to mount a finder with a guide camera on it do you think?
  2. It isnt a PE error - that occurs periodically and measurably - this is all over the shop and pretty much constant no matter the position of the gears.
  3. Hi All, I have an EQ5 motorized on RA with a 200p. For 2 years I did fine with tracking, gradually it got so the stars started trailing a bit so I decided to look into it. I'm fine with the PA and focus. I have replaced the motor, the thrust bearing on the main shaft, the main bearing on the main shaft, swapped the RA worm with the hardly ever used DEC worm, re-greased, I can see no wear at all even on close inspection. I have experimented with different tensions on the Worm drive to main ring and the motor cog to the worm cog. Nothing makes a blind bit of difference to the outcome no matter what I try. The following first two pics show my mount tracking with the mount rotated off PA by about 20 degrees clockwise - but in essence - I am deliberately trailing the stars whilst off-tracking so I can see if there is a pattern. So the first pic is an 11 min sub - a green line through a star trail shows the straight path the star SHOULD take. The second image is a zoomed in image of an approx 1 minute section of that long trail. The third image shows what the stars look like when tracked using this mount with strong PA, basically egg shaped (kind of) in the direction of the "bumps" on the trail - as we would expect. There is no "drift" over time - (well - about 7 pixels per hour) - what is happening here is the telescope is falling behind so the star moves "forward", then the scope catches up again and the star moves back into position creating a wavy line (mainly) but you'll see on the long line image that even this is not consistent. I am close to trying guiding now - but having replaced pretty much everything on the mount which moves - I am really confused as to what caused this - and more importantly, will this mount even work with guiding. Any advice/thoughts appreciated. Cheers
  4. The thing is that I write websites for a living - and nobody pays me - the most i get is £150 for two weeks solid work. In other words im skint as - so guiding is out of the question.
  5. I've stripped it all down now today and am changing all the bearings - will have to wait on delivery. PE on the RA worms are intermingled with this error on the images - I have seen the extreme errors occasionally and am fairly happy with that. Yes I am only tracking because I have no money. This problem has been progressively getting worse (I was browsing my old images). There is about 1mm or even less play on the main bearing (shown hanging on the shaft) - so I am replacing both bearings - see what happens. Took me two damn hours to get that sealed ring off the shaft - what a bind!!!
  6. Yes I had thought about doing EXACTLY that tonight!!! Because I thought "if only the star would stay in view longer I could get a repeat pattern!!" - I tried joining multiple exposures to achieve the same thing but it didnt work out very well. The "error" direction (the angle of the star blips within a frame) - when polar aligned - is equal to the direction of the tracking - so I have to find a nice angle for the North leg which allows trails in long exposures, but also shows the error clearly, as it will - if the angle is too small, overwrite itself if you see what I mean!!
  7. (I have even tested the ground stability!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!)
  8. Hi James - I have replaced the motor and its gearbox with new, there is no backlash on the worm at all now - during experiments, I have - if anything - very slightly over tightened everything just to eliminate. To no avail. No - there is no breeze - during my testing I ensure dead calm only - if there is even the slightest breeze I do no testing. Breezes tend to give a more random wobble too in my experience - but this error is consistent over many nights - always the same. I have overloading the east side to varying amounts over various nights - no effect - the error still occurs. I am thinking its the large main bearing in the RA head now - that is the only thing I have not managed to gain access to yet.
  9. Hi All - I track with an eq5, RA motor I added, SW 200p, PA = perfect, balance perfect and tried different things. I get stars deviating over time and then re-locating themselves in the correct position. So lets say I do a 1 min sub - I will get this when tracking (see small pic with stretchy stars zoomed in). If I point the north leg of the mount to east, then switch on the RA - I am tracking offset to the actual motion of the planet. Thus, I can now see the deviation of the stars on the mirror over time. But not all the stars show the same deviation / bumps!!!!! It is important to know that this is NOT drift. My alignment is perfect and the end of a 1 hour shoot results in only 6 pixels of drift. Whereas each shot can be 20 pixels out - but over time the stars come back into position - within a minute normally. I've got two examples below with star trails and ive coloured in a straight line to show how the stars deviate to give the stretched / jumpy appearance in the actual tracked properly image. I have stripped it (the mount) down - re-greased the worm gear and main ring, replaced the RA motor completely - but to no avail. Totally at a loss.
  10. Guys I cannot thank you enough!!!!!!!!!! THANKYOU - I would never have guessed "lens" spanner or "compass" spanner.
  11. Hi All I am trying to dismantle my EQ5 - but need the tool as shown in the photo. The thing is - not knowing what its called I cant find one online!!! I've tried pin spanner - but that doesn't get me the right thing - anyone know by any chance? Much appreciated.
  12. Hi All. Disaster has struck tonight. I track using a fitted RA motor and its been great for about three years. Then tonight, I noticed that the control knob on the mount for the RA was "thudding" very slightly with each motor pulse - ive never felt this before. On looking at the photos, I have trails on stars at 1min exposure Can anyone advise me what may be wrong? I changed the batteries but the result was the same. When moving the RA manually with the control knob it seems ok - smooth etc. But when the motor clutch is tightened, the thudding starts
  13. Fabio, sounds like you got a deal as good as it can get. What do you mean by these two things "the primary strongly tensioned (almost triangular), the focuser was squinted"?
  14. Hi Fabio, cheers for all the tips. I might look into shortening the tube myself - not sure yet - I will have to measure up the webcam and my camera focus to see how "little" I can get away with. If I ever sort out the spike - I will let you know - but its not looking like I will be able to.
  15. Yes - it does indeed - check out the post above from F in italy (an earlier one than the one with the star pics of his). In his post he says that the wide flaring is caused by the protrusion of the focuser so he cut his right back for astro photography. Which is why his stars above show round with no flaring - but note the one at the top - has the same artifact as mine (except mine is in more positions than his). This means (at a glance) - that the focuser is not the cause of the extra spike (given he has chopped his back - so has no flaring - but DOES have the extra spike).
  16. I'd be hard pressed to get the spiders more parallel than they are already without some kind of laser guided scientific device to be fair. They are all but hidden behind the yellow lines.
  17. That is incredible the way cutting off the focal tube has got rid of the flaring - how utterly stupid a design is that???????? The mind boggles. I can see your rogue diffraction spike too - if mine was in the outer region like yours rather than the middle of the image, I wouldnt bother with it. But unfortunately mine is all over the place.
  18. Will do that later today and test tonight if clear - yup. The rest is flocked.
  19. Ok - regarding the general flaring - I am not too worried about that, as I see it all the time on photo samples from the 200p where there are many bright stars in one shot. I admit - I don't like it - and may address it by cutting the focus tube down. The single stray spike is my pet hate though - I mean its wrecking my life (lol) - are you saying that is also characteristic of sw newts? Can you show me a pic displaying this problem from your 150?
  20. This is a close up of the star (just lower iso) - in the center of the frame. I think the flat left side of the circle is the intrusion from the focus tube maybe. (just for info really)
  21. Ive consolidated these into one image - pasting in the position of each shot. Im pleased with the collimation - the flaring is center in the center - and "directionally" towards the center in those images with the star around the edges. The green dots show the stars position when the extra spike does not show - the red dots are showing the spike. Strange or what? I will be honest - I dont know what this means or whether it helps at all? Just hoping someone will know where next to look.
  22. Ive done some pics tonight - moving a star around the mirror - interestingly, the spurious spike is in some pics and not others.
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