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alacant

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About alacant

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  1. 4.0.3575 Really annoying. Anyone know how to fix this? TIA.
  2. Thanks. Yep. I think I've got it; camera hanging toward the ground and no shift. The adjustment seems to have done it. Just hoping it will hold in real life. I wonder if the tilt from the lock screw is associated with the maladjusted focuser? Thanks for your time and help.
  3. Hi. How was the coma at the edges? Did it tilt the camera? TIA. *Am almost there with the adjustment to obviate the need for the lock...
  4. Hi. There is a lot of tilt and/or the cc is at the wrong spacing. It needs 75mm from the shoulder of the m48 thread to the sensor. So, collimate again with cross-hair Cheshire and have another go. Note: it seems a pity to have such a fast telescope and then use a cc which makes it slower. A Baader or a SW cc maybe worth considering. The former leaves the fl unaltered whilst the cheaper variety of the latter would give you a 10% reduction and an addictive f3.6. HTH.
  5. Ah, OK. That's a good one to check. It seems fine no matter where the focuser is, but I use a Cheshire with cross hairs rather than a laser. I think however it should amount to the same end...
  6. Hi. Yes. I'm proceding according to these instructions. Nearly there...
  7. I think so. Would it collimate if it were not? TIA.
  8. Hi. Thanks. It's only a matter of time, trial, error and a few cloudy nights before I get the right combination of twisting and turning to get the focuser o hold! The main issue is that the focuser lock tilts the field. If I can take the latter out of the equation, I think the issue will have been solved. Until...
  9. Hi. Thanks for the link. Yes, it looks like that on the right of the image. That's why I think the focusing lock is tilting the field. That discussion was for field flatteners on refractors. Does the same apply to coma correctors on newtonian reflectors?
  10. Hi everyone. Here's a light frame with the field deliberately tilted with the focus lock screw. It's distorting the stars, but not producing coma. Strange. This much tilt on my faster f3.9 and it would be coma city. Does anyone know what this effect is called? TIA.
  11. Hi. Yes, a Cheshire is all you need, one with cross hairs is even better. There are a lot of idealised diagrams in the guides which look nothing like the real thing. Here's what it actually looks like through a 130pds looking through the focuser with and without the Cheshire. 1. Get the secondary more or less centred just by looking at it. 2. Insert a Cheshire with cross-hairs. 3. Use the secondary screws to make the cross-hairs intersect with the centre of the of the primary. 4. Adjust the primary to centre everything else. 5. Now go out and look at an out of focus star. Adjust the primary again tiny amounts to make it circular. Forget all that. Just make it look like this:
  12. Hi. I had a go at the tension but unless the telescope was pointing overhead, still couldn't get it to stop slipping . Even the slightest turn on the lock screw -not even trying to lock anything- and it tilts. You can't see it so much in a stacked image, but here's a light frame from the same; alas with the lock screw tightened...
  13. Hi and welcome. It's easy. As soon as you get to do it on a telescope, you'll see it's intuitive and will wonder what all the fuss was about. Some guides make a simple one-minute task seem horrendously difficult. So have a quick Google, but don't read too much about it before you try! FWIW, I already had a 200mm telescope and got the 130mm because of the wider field of view. If you have a choice of which to get first, I'd recommend the 130mm. Good luck and clear skies...
  14. Excellent. I think you ought to write the pds guide for removing the out of box nightmares. Yeah. Even more surprised. They don't seem to have anyone on the ground, in the cloud or anywhere. If I have a problem with my Bresser, I send an e-mail to ES and they get back to me that day. Maybe I'm not comparing like with like but SW don't seem to do it like that(?). Anyway, it's clear again tonight so I'm gonna stop feeling sorry for myself and go and take some snaps!
  15. That's the problem; tighten it and it tilts the focus tube and/or changes the focus. The only way I could keep it flat was by trial and error between adjusting the two screws which hold the camera-cc combination in the focuser tube to 'anticipate' the tilt before I turned the locking screw. Am going to try your adjustments to see if I can get the focuser to hold without having to tighten the lock screw. Thanks for posting. There is hope...