Ha gong images vs actual ha views at scope

[GavStar]

I’ve just been observing the sun with my lunt 60 double stack for the first time this year. Some great views. 
For comparison purposes, I downloaded the current solar pic on ha gong - how close do your live visual views get to the images shown (both surface detail/contrast and prom detail)? example from today attached.

Edited April 9, 2022 by GavStar

[Oldfort]

Through my PST, I reckon the proms look better, but gong is some way ahead on surface detail.

[Roy Challen]

It depends,😄 not all GONG images are particularly good.

I find my prom detail in a Daystar Solar Scout is better than GONG but disc detail is less good. But not much less. Contrast is better with Daystar too, but, again, you have to 'key your eye in' visually at least.

I tend to use GONG as a barometer of what there is to see on any given day.

Cerro Tololo and Learmonth are the best on GONG, the others are barely worth looking at.

Edited April 9, 2022 by Roy Challen

[GavStar]

Yes I generally just look at Cerro Tololo and Learmonth gong ha for indications of activity.

Yesterday I compared single eye observing (Pentax zoom) vs binoviewing with my mark v, 1.7 gpc and 19mm panoptics to give around 40x. Despite double stacking, the binoviewers gave nice bright views which clearly surpassed the monoviewing. The actual views I got surpassed the Cerritos Tololo gong image for surface and prom detail - amazing dark contrast on the surface. I guess seeing was pretty good - really looking forward to the sun showing even more activity going forward. 😀

Edited April 10, 2022 by GavStar

[Highburymark]

Have you tried pushing the Lunt to 60-70x with a binoviewer Gavin? Your LS60 should be capable of higher powers in good seeing - especially at the moment with so much surface activity. This should bring out better detail of proms and filaments, without dimming the image too much. I find that different magnifications are needed for different features. I start at 65x with 25mm eyepieces - often that is all the seeing will allow, but under better conditions go up to 100x, and sometimes 11mm eyepieces and 2.6x gpc for 135x with TV85 and 70mm filters. Obv at those powers the filaments aren’t as dark but still show new detail.

[GavStar]

9 minutes ago, Highburymark said:

Have you tried pushing the Lunt to 60-70x with a binoviewer Gavin? Your LS60 should be capable of higher powers in good seeing - especially at the moment with so much surface activity. This should bring out better detail of proms and filaments, without dimming the image too much. I find that different magnifications are needed for different features. I start at 65x with 25mm eyepieces - often that is all the seeing will allow, but under better conditions go up to 100x, and sometimes 11mm eyepieces and 2.6x gpc for 135x with TV85 and 70mm filters. Obv at those powers the filaments aren’t as dark but still show new detail.

Previously I’ve preferred staying at around 30x for maximum contrast. But yesterday I moved up to 40x which was great. I do have 10mm and 12mm pairs which with my preferred 1.7x gpc will take me to 60-70x, so I’ll try that next time. 

[Stu]

Hard to compare as I normally view using binoviewers at high power. Not totally sure what high power is, but scope is 1000mm focal length and I use 40mm Plossls with a x2 barlow in the nose of the binoviewers. Say that becomes x 3 and I’m at x75. Certainly the image scale suggests at least this.

Using lower power, with a single eyepiece, the views are comparable with gong, though brighter and more detailed especially in the proms. Surface contrast on filaments is about the same from memory. At high power there is no comparison. Proms are far larger and with much more detail. Surface detail is larger and high resolution, although filaments have less contrast as it is not a double stack.

Example of an admittedly large prom attached. Visual view was much more detailed, finer features resolved.

[BGazing]

Interesting question, I guess it depends on the conditions (both at one's observing site and at a particular GONG site) and the equipment.

I use Quark, more often in 100mm than in 70mm, minimum magnification at 40mm plossl in a bigger scope is around 77x, but the view is constricted. Normal good seeing is 95x, and at that power proms are pretty good and if the seeing is stable there's considerable surface detail to be discerned. At 125x prom finesse disappears but they get really impressively big, seeing permitting. Filaments are usually the most difficult to see, I guess they benefit from somewhat lower power.

I'll try binos in 70mm, in 100mm there was vignetting, don't know if that is because of the size of the etalon or because of the size of that 12mm blocking filter.

I am mulling splashing on a 80mm Lunt, so curious to hear what are the upper limits of your solar scopes with and without the binos. How significant is DS dimming?

[Highburymark]

5 hours ago, BGazing said:

Interesting question, I guess it depends on the conditions (both at one's observing site and at a particular GONG site) and the equipment.

I use Quark, more often in 100mm than in 70mm, minimum magnification at 40mm plossl in a bigger scope is around 77x, but the view is constricted. Normal good seeing is 95x, and at that power proms are pretty good and if the seeing is stable there's considerable surface detail to be discerned. At 125x prom finesse disappears but they get really impressively big, seeing permitting. Filaments are usually the most difficult to see, I guess they benefit from somewhat lower power.

I'll try binos in 70mm, in 100mm there was vignetting, don't know if that is because of the size of the etalon or because of the size of that 12mm blocking filter.

I am mulling splashing on a 80mm Lunt, so curious to hear what are the upper limits of your solar scopes with and without the binos. How significant is DS dimming?

I suspect the 80mm Lunt (internal etalon) will have similar power limits to my 70mm Solarscope (external) filters. Normal seeing, with binoviewers, I observe at 75x-80x. Good seeing - 100x. And under best conditions, I use 11mm Delites or Plossls - around 140x. At that power, the double stack 70mm view is quite dim, but well worth the effort. With the brightness of a single stack LS80, you might be able to go even higher - particularly on prominences - but it will be seeing dependent.

[niallk]

On 09/04/2022 at 12:43, GavStar said:

I’ve just been observing the sun with my lunt 60 double stack for the first time this year. Some great views. 
For comparison purposes, I downloaded the current solar pic on ha gong - how close do your live visual views get to the images shown (both surface detail/contrast and prom detail)? example from today attached.

My double stacked Lunt 50mm beats Gong images on surface detail.  In particular, I can focus to a sharper degree revealing subtle fine detail, imho.  Similar to gong on proms, except sharper.  The pressure tuning then allows different features to be accentuated.  I use a TS zoom EP, but it degrades views below about 8.5mm.  I can get better results with a 2.5X PM and fixed focal length EPs.

Edited April 12, 2022 by niallk

[niallk]

PS I'd love to be able to binoview with the LS50, but focus travel issues...

I once observed through a TV Binovue in a LS60 double stacked with a 50mm front etalon, and it was just stunning 😎

It's what made me get my own kit!