Hello,
For a white light observation with a solar Wedge, is best an Apo or ED lens refractor,or an achromatic refractor ? the focal lenght is indiferent? best more aperture, for example a 120mm F/8 achro. refractor that an 80ED F/7.5 or F/6 ? the CA is not intrusive in the achro refractor with the solar wedge ? all questions is for visual observations
thank you in advance for your opinion and experience
pluton
Apo or Achromat.refractor for visual WL.
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Re: Apo or Achromat.refractor for visual WL.
Pluton,
On the assumption you are also using a Continuum (or OIII filter) with the wedge - there's no need for an APO.
I use both the ED80 and the TS102 f11 with no issues.
On the assumption you are also using a Continuum (or OIII filter) with the wedge - there's no need for an APO.
I use both the ED80 and the TS102 f11 with no issues.
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Re: Apo or Achromat.refractor for visual WL.
For solar works it is MUCH better to have a larger achromat than a smaller APO! You will much more per $.
Or better to spend the difference in the cost between APO and Achro (the same size) for a better filter, say, for a
good Quark or even better filter.
APO is for planetary observing (visual) and deep sky imaging (wide to middle field).
Valery
Or better to spend the difference in the cost between APO and Achro (the same size) for a better filter, say, for a
good Quark or even better filter.
APO is for planetary observing (visual) and deep sky imaging (wide to middle field).
Valery
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Re: Apo or Achromat.refractor for visual WL.
Hello,
Thank you for your response.
But dont´like the visual image with the Continuum filter, only with the polarizer(plus a ND3 filter) filter, there is too much CA with the Achro refractor?
For example, an Achro Celestron Omni 120mm F/8 can be a good alternative to a ED80 refractor for visual observations?
I did, these have more resolution, but,,,, it have CA bothered me ?
I think that a ED or APO refractor have more contrast in the image...but, I like looking solar granulation...., 80mm is sufficient for this ??
Thanks again for tour advice.
Pluton
Thank you for your response.
But dont´like the visual image with the Continuum filter, only with the polarizer(plus a ND3 filter) filter, there is too much CA with the Achro refractor?
For example, an Achro Celestron Omni 120mm F/8 can be a good alternative to a ED80 refractor for visual observations?
I did, these have more resolution, but,,,, it have CA bothered me ?
I think that a ED or APO refractor have more contrast in the image...but, I like looking solar granulation...., 80mm is sufficient for this ??
Thanks again for tour advice.
Pluton
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Re: Apo or Achromat.refractor for visual WL.
In spite of the residual CA the 120mm achro will be much better than the smaller 80 APO for WL. I have a 150mm achro and a 90mm apochromat, both are fine and show lot of details however the achro wins in resolving fine structures in granulation and penumbrae.
Based on my experience, for a 120mm f/8.3 filtering the CA is not strictly necessary in observing the Sun in WL. Surely there is no need of a heavy filter as the Baader Continuum (unless you want to do some imaging), visually a light yellow W8 or a Baader Fringe Killer will work fine as well.
Based on my experience, for a 120mm f/8.3 filtering the CA is not strictly necessary in observing the Sun in WL. Surely there is no need of a heavy filter as the Baader Continuum (unless you want to do some imaging), visually a light yellow W8 or a Baader Fringe Killer will work fine as well.
Raf
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