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Afocal Video through a Daystar Solar Scout SS60-DS - here's what you can expect to see.


chops

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I'm posting in the hope it helps anyone else considering a Daystar Scout SS60. The video's not quite representative of what one sees looking through the scope, but gives a general idea of field of view through a 24mm EP.  When observing, much more prominence detail and surface texture is visible to the eye and the colour feels less red than it appears in the vid.

I'd have taken this video sooner if I'd realised that afocal video would work so well, so I'll try again next time the sun's available earlier in the day during better seeing. The video's taken by holding an iPhone against an Explore Scientific 24mm eyepiece and adjusting exposure (i.e. afocal video photography). Although I find a Plossl as easy (if not easier) to use as a wide EP for observing, it's simpler to align a smartphone with an eyepiece that has a wider field of view, for afocal video. Hence I used a 24mm ExSc (see below for detail). It seems a fairly quiet solar day, not long after the notoriously quiet 2020 and I believe is still close to the beginning of the sun's new 11 year cycle (hopefully it will become more exciting soon but not as exciting as having any Carrington Events pointing towards us).

I spent some hours, from late morning, watching these prominences form, dissipate and reform. The prom on the Western limb was very tall and bright, looking like a large rectangular tower block, which gradually split, faded as the top looped over to the north, then the top looped back again to the south. At one point this loop appeared to join - forming the outline of the head of a man, whose figure, with arms out, was clear and rather funny. Wish I'd taken this video sooner (or had the ASI183 to hand). The prom quietened and reached its current state (3pm ish) as seen in the video.

The long group of prominences to the South - 4 main and some smaller - were more dim than the prom on the Western limb initially, but they remained impressive, ranging from good to very small and appeared at one point to be as clear row of pine trees, especially the larger right hand prom, with spiky 'branches' and a distinctive triangular fir tree shape, which gradually brightened then faded to this view. The tip of the ‘sharks fin’ to the left of the group extended out to the east then receded.

I'm afraid it's not easy to see the detail in such a simple video - it's slighly more visible to the naked eye. By the time I took this video it had gone 3pm, there was more haze and a lower sun and none of the prominences were particularly impressive.

There were No sunspots easily visible, although a Plage appeared to be visible close to the Westerly limb. Little surface detail other than orange peel, despite tuning the scope (better with the SS60s dial to left of centre for this today). I still need to lots more time with the scope to get the best from it.

I'm a Ha beginner having only observed in whitelight before and only having used this scope twice before, once in combination with a ZWO ASI 183MC astrophotography video camera. Medium seeing, 6/3/21 'third light' on the Daystar Scout SS60 Scope with fixed chromasphere quark built in - 930mm f15 60mm.

Various Eye pieces used: Plossl 40mm, Meade Super Plossl 26mm, Explore Scientific 24mm and 11mm 82 and 68 degree EPs gave good clarity and contrast, but the seeing's not good enough for close viewing of proms.  ioptron motor, roughly pointed north was perfectly sufficiently good to keep the sun in view for at least 45 mins at a time. I'll edit this post to add a pic or two of the equipment setup in a moment.

3 images attached are: Afocal Smartphone still image (contrast increased in smartphont), plus two shots of the setup.

 

6th March 2021 afocal Ha.jpg

6th March 2021 observing with Daystar scout SS60.jpg

6th March 2021 setup observing SS60 Daystar scout.jpg

Edited by chops
add 3 still images as described in text. later grammatical correction
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  • chops changed the title to Afocal Video through a Daystar Solar Scout SS60-DS - here's what you can expect to see.

Thanks Roy, here’s another still in slightly better seeing (from mid morning today) and the surface granulation’s beginning to be visible in the stills, as it is at the eyepiece. Plus a rather fun gif from when a gull crossed the solar disc, just as I happened to be holding the phone against the EP.

A08E85CA-9936-4FEB-BFC6-BB7EAEA2087D.jpeg

F337B74A-4010-4D65-BC2D-DB4502CF1872.gif

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  • 2 weeks later...

By way of an update, I bought the (Daystar recommended) 32mm Televue Plossl to use in place of the 24mm 68 degree Explore Scientific, 40mm unbranded plossl, and trusty 26mm Meade 4000 super plossl LP I've been using.

However, I'm slightly disappointed so, by way of comparison:

1) The solar disc size is ideal in the TV 32mm EP, compared with the 40mm and 26 or 24 mm. This is irrespective of TV's 50° aparent field of view, versus the 24mm's 68° AFOV (the 68 degree is easier to 'use')

2) Contrast is better than the other plossls, but only marginally better than the ExSc

3) However, it's not as good as I hoped, because of (I believe) needing an accurately positioned eye (vignetting) due to a very small exit pupil. Eye relief seems OK - indeed I have to pull back from the EP slightly which, with solar work, means having to shield from the stray light. The ExSc by comparison I can push my eye right up against, for a dark view.

I'm afraid I don't know enough about the causes of this, other than the different field stop of each EyePiece, when used with the 930mm focal length of the SS60 and the (I believe) relatively small 12mm etalon aperture that we're looking though.

Can anyone shed some light on the issue please?

Edited: Updated below with EP stats

Explore Scientific 68° (ref: https://www.firstlightoptics.com/explore-scientific-eyepieces/explore-scientific-68-degree-series-eyepieces.html)

Model     ExSc 68° 24mm      
Product Code     0218624      
Eye Relief     18.4mm      
Field Stop Diameter     27.2mm      
Barrel Size     1.25” / 31.8mm      
Barrel Length     23.5mm      
Waterproof     Yes      
Lenses     6      
Lens Groups     4      
Height (From end of barrel)     55mm      
Width     62mm      
Weight     370g      

 

Meade 4000 Super Plossl LP: https://www.meadeuk.com/Meade-Series-4000-Super-Plossl-Eyepiece-26mm.html

No Field stop published on Meade, but reported at 23.9mm elsewhere (don't know whether either of these match my 'LP' Low Profile version originally supplied with ETX125).

Focal Length 26mm
Optical Coatings Multi-Coated
Barrel Size 1.25" (26mm)
Apparent Field of View (FOV) 52°
Eye Relief 18mm

 

Televue Plossl: https://www.televue.com/engine/TV3b_page.asp?ID=51&Tab=EP_EPL-32.0

32-mm
Model # EPL-32.0
Focal Length (mm) 32
Barrel Size (in.) 1¼"
Apparent Field of View (deg.) 50
Eye Relief (mm) 22
Weight (lb / oz) 0.39 / 6.2
Field Stop (mm) 27
Edited by chops
adding 3 x Eyepiece stats for comparison
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TV Plossls give brighter and slightly sharper solar views than other Plossls - though they obviously won’t turn an average etalon into a top performing one. Unfortunately the 32mm has very long eye relief, which I think is the problem you’re having - not vignetting, which is when you can’t see the full fov/field stop of the eyepiece . For this reason TeleVue makes eyeguard extenders which can be added to the EP, and means you can use it close-in - like your 26mm plossl - and block out the surrounding light. 

D4235E25-296B-4C10-B623-2042B5921DE6.jpeg

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@Highburymark many thanks, that makes sense. I wonder why Televue don’t simply include a longer fold up rubber eyecup, which would achieve the same thing for many of us wondering whether we’ve been sold a pup. Yes, contrast is undoubtedly better than the Meade Plossl I’ve been using and sharpness noticeably better too, but without lifting my eye another few mm off the eyepiece (which makes it useless for solar viewing because of stray sunlight) it’s nothing like as useable as the cheaper eyepieces.
I’ve been looking at a Dioptrix, which I assume will achieve a similar effect to the eye guard extender.

ps whilst it’s not visual observing, here’s an image from a stack of frames showing that lovely prominence - and the reason I’m including it is because I can see this detail with the eye whilst using the scope (albeit nothing like so highly magnified) and so I believe it’s a fair representation of the capabilities of the SS60 for observing.

01887AFF-0717-4D40-8129-A6037795493D.jpeg

Edited by chops
Added image of prominence as higher mag representation of what can be seen visual observation
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That’s a cracking image! It sounds as if your SS60 etalon is a good one, though it may be better on proms than surface detail - I have a Quark which produces stunning prom views, but I haven’t yet got the same results on filaments and active regions on the disc itself. I need to play around with it more, and maybe reduce the aperture (I use it with a 100mm refractor) to slow down the focal ratio. 
I agree with you on the TV32 - they should provide an extender as part of the package. Buying it separately makes it a very pricey plossl, but you are rewarded with improved results.

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@Highburymark thank you, it’s great to hear. Re your sleeving down, I saw an interesting post here, or cloudy nights of someone using a rubber cup of some sort to shim down the objective lens to increase the focal ratio to good effect. If I find it, I’ll post it up. 
You’re right, the proms on this scope are great; I have little to compare it to, but there’s less surface detail than I can see in the prominences. That said, image attached (that I’ve pushed quite hard), from the same AVI which produced the proms above, that shows a little detail, but I can’t push the magnification much at all with the scope, without hitting the limits quickly... I guess that’s the advantage of a full Quark vs the Daystar... but absolutely no complaints for the price and accessibility of the Scout SS60.

29163BEE-076F-4A0F-B3A6-6794CDFA8142.jpeg

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@Highburymark thanks for the eyepiece extender tip. It arrived yesterday and I tried it this morning with the Televue 32mm Plossl. Significant improvement and much more comfortable. I still found myself reaching for the old (Taiwan model) Meade Super Plossl 4000 26mm which works well and, of course, wishing desperately that the Binoviewer would work with a diagonal and the SS60. I still also prefer the views through an Explore Scientific 62 degree 24mm... but there’s no doubt the Televue 32 is sharper and has more contrast. 
The pic shows white light ETX125 and the SS60 with the above config, plus another in straight through binoviewer mode.
Now what would be perfect is the SS60, diagonal, 2 x Tv32, 1 x eyepiece extender and 1 x dioptrix to correct astigmatism. Here’s hoping!

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