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  #21  
Old 02-03-2019, 10:24 AM
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mental4astro (Alexander)
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Originally Posted by Ukastronomer View Post
barlow on a Quark, I thought it had a barlow (telecentric) built in dumb question, add another ???
No, not a barlow. The opposite, put a focal reducer in the eyepiece.

One of those cheap 1.25" 0.5X focal reducers you can get say from Ebay:

Ebay 1.25" 0.5X focal reducer

The picture in that ad shows how to use the reducer ON THE EYEPIECE. Do not put it on the Quark. I use my focal reducer with my 25mm plossl eyepiece.

The reducer won't magnify the image. It will actually make it smaller. What this does is concentrate's the Sun's image into a much smaller image, and this can help our eyes more easily identify some features. Like you suggest, it makes no sense to add another barlow to a Quark. What we want to do is REDUCE magnification

There's a few little tricks that can be done with a Quark:

* Changing between a couple of eyepieces or using Zoom eyepiece
* Using a focal reducer
* Using an aperture mask to reduce the effective aperture of the scope.
* And of course tuning the Quark as conditions change.

I use all of these with my Quark. These are all just little tools that help exploit the Quark visually. I can use all of these during a session with my Quark, not relying on just one single tool for the one single observing image.

Photography with the Quark is a different matter. The image of the Sun in photography is manipulated externally through a computer. Even this processing takes its own time and experience, and is not an instant fix. The dynamic range of the light from the Sun is really challenging to deal with photographically. A lot of work goes into producing a photo that shows proms, granulation, filaments and sunspots. And sometimes the most subtle of features just cannot be seen on a photo, but can only be seen visually. That is why I LOVE my Prom. Quark. Solar photography is a really niche discipline!

Everything that you see in Ha photographs of the Sun you can see through your Quark. But our eyeballs are different from cameras and computers, so we need to use different methods to exploit the Quark. Even with a dedicated Ha telescope, there are different visual tricks that can be used to improve the visibility of different features, not just the Quark.

Alex.
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  #22  
Old 02-03-2019, 08:15 PM
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Ukastronomer (Jeremy)
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"No, not a barlow. The opposite, put a focal reducer in the eyepiece.

One of those cheap 1.25" 0.5X focal reducers you can get say from Ebay:"

AH..................... thanks

I have a few of those
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  #23  
Old 02-03-2019, 10:00 PM
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mental4astro (Alexander)
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Remember, a focal reducer is just one tool to use and exploit during your session. It is not the only item to use, nor will it reveal everything you want. Use in combination with other techniques.

Alex.
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  #24  
Old 02-03-2019, 10:19 PM
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Ukastronomer (Jeremy)
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Originally Posted by mental4astro View Post
Remember, a focal reducer is just one tool to use and exploit during your session. It is not the only item to use, nor will it reveal everything you want. Use in combination with other techniques.

Alex.
Learning ..................................: )
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  #25  
Old 02-03-2019, 10:22 PM
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I am ordering this in a week

https://www.widescreen-centre.co.uk/...nt-tripod.html

As I said I have problems doing more than one thing at a time adjusting the Quark, tracking, looking, re adjusting all on a MANUAL mount, so this will help with my disability and allow me to try out everything the good people of this forum have advised me to,
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  #26  
Old 02-03-2019, 11:24 PM
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mental4astro (Alexander)
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Looks like a useful bit of kit.
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  #27  
Old 04-03-2019, 07:40 PM
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Hi Jeremy et al, here is a shot* taken from sea level in less-than perfect seeing through 70mm of aperture and a Herschel wedge in September 2017. White light. Granulation is visible, even if individual granules are not. They are still a photospheric (read: white light) feature, so a H alpha setup is not needed to see them. If anything, it probably makes them harder to see. What a H alpha setup will show, and a white light rig won't, is the chromospheric network, itself caused by supergranulation beneath it.

https://solarscience.msfc.nasa.gov/f....shtml#Network


*actually a short video with some stacking applied.
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  #28  
Old 04-03-2019, 11:09 PM
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Hi Jeremy et al, here is a shot* taken from sea level in less-than perfect seeing through 70mm of aperture and a Herschel wedge in September 2017. White light. Granulation is visible, even if individual granules are not. They are still a photospheric (read: white light) feature, so a H alpha setup is not needed to see them. If anything, it probably makes them harder to see. What a H alpha setup will show, and a white light rig won't, is the chromospheric network, itself caused by supergranulation beneath it.

https://solarscience.msfc.nasa.gov/f....shtml#Network


*actually a short video with some stacking applied.
All replies much appreciated and printed off for my folder
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