Solar Granulation

20170522, Jerusalem

Meade 10" Classic + Astrosolar D 3.8, 720nm near IR filter, ASI174MM camera.
Acquisitions with FireCapture 2.5, 8 bit SER, shutter 1 ms, gain 130 (32%), gamma 1, histogramm =83%, time 06:41 to 08:15 UT.
SSMonitor recorded automatically SER files when seeing was not too bad. Registration of individual SER files with AS!3.
Of course aspect changes completely on this time span and without the sunspot there would be absolutely no way to align the frames !
Due to bad seeing I had to remove a couple of frames ... 75 kept out of 78 !
Result frames were registered with RegiStax5 using prefilters around the central sunspot, saved as AVI then selected in VirtualDub, exported to PNGs,
Cubed in StarMax, level and gamma again in VirtualDub, before final conversion to GIF using PIPP.
Animation shown here at 50% size ... needs about 30s to download !
Click on animation for full size GIF (visible in navigator but 92 MB !) or if you can download .AVI (xvid 21 MB) or .MOV ( 7 MB).
Interesting : during this long acquisition time, the sunspot expands (registration was on the center one) and you see the little dot moving towards to top left !


20170518, Jerusalem

Same setup as on May 14.
Today there the little sunspot AR2656 is today a bit farther from the limb and can be used to align the 40 min animation ...
without a sunspot as reference, as all the structures change radically in a few min it is all but possible to align !
See end of page example @ La Palma ...
Below is the general aspect registered from a good seeing sequence (10h56 LT / 7h56 UT) ...

Click on images for full size...

GIF animation of about 40 min real time ...
Word of caution :
Please be patient, files are large as quality must be preserved as much as possible !
Animations will play at normal speed only after complete download.

GIF animation of about 40 min real time but all frames have been cubed pixel by pixel !
You can see better that there are 3 kinds of moving structures :
small dots, granulation & a kind of little dark patches !

Around the sunspot full size ...
I have the feeling that the sunspot is surrounded by dots moving away from it ?

What are those large structures seen in dark, is it waht is called super granulation ?
Below is an highlighting ...
Click on the image to see the mask extracted and colorized.

Now, if interested, you can study this on the original live video (at speed of acquisition 42 FPS) :

Link for compressed GIF file (140 MB = 15 min download at 150 KB/s).

Right click as "'Save link as..." for original uncompressed SER file (280 MB = 35 min download at 150 KB/s).
The SER files can be played / edited / converted with SER-Player freeware from Chris @ Astro-PIPP website !

Frames shown here=121
File type=SER
FPS (avg.)=42
Gain=86 (21%)
SSSMon best seeing=0.54

20170514, Jerusalem

After many trial in Continuum, UV and K-Line, I was told about possible better results in Red light. As I have no Red filter under hand, I used a 720 nm near IR filter instead ...

Setup : Meade 10 Classic with front aperture Baader D3.8 filter, SSM = Solar Scintillation Monitor, 3x 1 1/4 Televue barlow FL~7500mm),
Near IR chinese 720 nm filter fitted with special ring, ZWO ASI 174MM B&W camera, JMI motorized focuser.
FireCapture 2.5, 8 bit SER, 51 avg. FPS, shutter 3.5 ms, gain 50 (12%), gamma 1, histogramm =71%, time Mid = 052037 UT .

Clic on picture for full size (Full HD 1080p)

Processing to get this image :

The original movie it has been first contrasted in SER-Player (gamma 0.10 & gain 140),
registered in AS!3 (2858 AP size 48), sharpened with 25% blend RAW, then Wavelets in RegiStax6 (025-100-146), slight crop in IrfanView..

Please clic on a link below to see a Full HD 1080p High-Resolution view of solar granulation ... as if seeing it live !

AVI for PCs or MOV for APPLE

I have never seen this on the Internet ...

Very good seeing video
showing at acquisition speed (66 FPS) most of the FOV of the ASI 174MM (registered with RegiStax6, 100 AP then saved as AVI) !!

If you have slow Internet there is below for you the small video to give you an idea :

I shown the surface of the Sun at high resolution during rather rare very good seeing (SSSMon best seeing =0.49) in near IR (720 nm) !
The GIF movie below is a very small part, not registered - moreover slightly reduced size -
of the FOV of the ASI 174MM sensor as the original full size movie for 20s recording was ~2.2 GB !

Notes on PIPP GIF conversion parameters to stay < 5 MB ::
Neural-Net Quantisation Algorithm, Smaller file size, unchanged Border tolerance 5,
Transparent pixel tolerance unchecked, reduced Color table bit Depth 6, lossy compression level 20,
resulting GIF size of this little animation = 4975 KB.


Below the aspect seen on the monitor during acquisition (as played here later with SER-Player) ...
until a new FireCapture version would enhance the low contrast flux in live ... already setup with gamma 1 !
This would also permit tracking on hard to see solar features !





A session aborted by cloud arrival (20150610) then missing sunspot 2365
Seeing not bad ...

Of course those are not great images from granulation but it is what I can get with a standard LX200GPS.
Extraordinary images can be obtained with top equipment, in good seeing with specialized solar Newtonian telescopes, by experimented solar astrophotographers as here.

Click for full size

Sun : FujiFilm HS10 + 1.5x extender + visual solar Baader mylar. 6 x Fuji RAF RAWs aligned with PiPP & RegiStax5 in CG mode.
Granulation : LX200GPS 12" + 2.5x Barlow (FL = 7.500mm) + Baader D3.8 solar photo filter + Baader Continuum filter + 2 x Baader IRCut + ASI174MM camera at full size, gamma 0
Each image result after AS!2 (25% best) of a 1 min 8 bit SER file (Firecapture), processing Astra Image LRD 150'17i and levels 9456..43862
Single frame
Clip available in XVID compression 3 showing seeing (100MB, right-click to download)


An interesting session (20150518) click for full size

Acquisition : FireCapture 2.4
Focusing is difficult !

Registration AS!2 (10% best kept for top and middle images, 30% for bottom image)
Enhancement of features : Astra Image 3.0 Lucy Richardson deconvolution (Img1=LRD070'13i, Img2= LRD080'13i, Img3=LRD140'6i then stretching)
Colorization GIMP2 (Map, sample colorize from another Halpha picture)

Note : The sky was perfectly clear but is was a windy morning ! I had to wait for some rather quieter moments to start captures.
Also the rolling shutter of the ASI120MM made strange wobblings at high magnification (with the 2.5x Powermate).
It is the reason I switched for the ASI174MM which has not this problem.

What king of quality in the originals captures ?

With 2.5x barlow : A good frame ... Only part of it are rather good !
click for GIF showing about 100 frames (interesting but 48MB download) in full size



The beautiful lacework of sunspot 1515 ! This is my best picture in white light, I guess because the sun is very high Summer solstice ...

Even more penombra resolution after putting lots of APs on the sunspot ...


Reference images to see how fast the granulation changes

(Sources :

Animations (from SVST, La Palma) rate is 2 frames per second at total duration is like above, 147s (7*21s)