PST for whole disk ( and also prominences high resolution images

In general click for larger images ...

June 19, 2015 / PST and DMK31 Testing DSSR scan !
A promising beta development of my drifting technique has been implemented in DSSR.

Here is the first result in RegiStax5 (expand mode) and AstroImage 3.0 Processing (LRD 0.53'17i) :

Acquisition FOV (DMK31 @Main focus) :

Scan Parameters:

RA d sec 50
D d sec 1 (0 is not allowed)
Dd ms 100
EtG pix 50


May 6, 2015 / PST and ASI120MM-S ... A new improvement of the drifting technique !
Reminder : original FOV with the camera :

The problem leftover with my drifting technique was that the extreme parts of the drifting got much less frames than the center. The consequence was 2 noisier zones : see Mars 3 image and look at right/left (good) then top/bottom (worse).
In earlier attemps, when I acquired more images at these extremes before and after drifting, I got a few annoying horizontal lines at the level of drifting begin and end.


I tested a new solution today are the results are - despite strong winds - much encouraging ... Prominences at top and bottom are not noisy !

1 AS!2 Registration of AVI, saved as 3 layer PNG
AS!2 Conv sharpened with blend 50/50
Astra Image LR deconvolution 0.80, 12 iter
Astra Image LR deconvolution 0.80, 12 iter + curves (slight prominence enhancement)
Idem image 4 Map Sample colorized in GIMP + Contrast 20 / Lum 30
Idem Image 5, inverted then Hue at left for pink version

The idea is to do some up-down movements for 20s at begining and end of the tranlation.
Best speed is 2x guiding rate. The exposure should be short, not more than 5 ms !

See the reduced size Movie (xvid) showing the movements in real time ...


New : Apr 29, 2015 / PST and ASI120MM-S ... drifting (a few vertical back and forth)

drifting moves (very small size but real time)... will try bigger images later

Processing : Best registration with REGISTAX5 !



Apr 07, 2015 / PST and DBK21 ... Testing the drifting technique
with random moves in all directions with the smallest sensor available, 640x480 :)

Guiding softwares would do it better !
A point not to forget : when inverting DEC I think something should be done to take care of the long lag time at guiding speed ...
Accordingly this one was done at 8x speed in ~90s...

FireCapture v2.4 Settings
Scope=PST sS
Camera=DBK 21AU618.AS
Frames captured=5191
File type=SER
Bit depth=8bit
FPS (avg.)=60
SoftwareGain=10 (off)
FPS=60 (off)



New : Apr 07, 2015 / PST DS ASI174MM

FireCapture v2.4 Settings
Camera=ZWO ASI174MM

Date=070415 Mid(UT)=155702.732 Duration=60.001s LT=UT Frames captured=5474

File type=SER Bit depth=16bit
ROI=832x800 FPS (avg.)=91

Shutter=10.00ms Gain=284 USBTraffic=60 Gamma=50 (off) Limit=60 Seconds
Registration : AS!2 Planet mode,

Processing Lucy Richardson deconvolution in Astra Image 3.0 : 0.5 / 18i,

Gamma Curves in Wx (click for larger)


Mar 25, 2015 / Simple PST imaging (single stack today)...
Just eyepiece projection (Seren 8 - 24 mm, @20 mm) and Canon SX230HS in P mode
(2s delay to avoid shaking) maintained with a rubber band against the eyepiece ...

Same with PST-DS (double stack) should be done asap !

Rather dark image for disk ... Light image for prominences ...  

Model - Canon PowerShot SX230 HS
DateTime - 2015:03:25 16:57:01
ExposureTime - 1/200 seconds
FNumber - 4.00
ISOSpeedRatings - 100
FocalLength - 10.80 mm

Filename - IMG_1501.JPG
DateTime - 2015:03:25 16:57:42
ExposureTime - 1/8 seconds
FNumber - 4.00
ISOSpeedRatings - 100
FocalLength - 10.80 mm

Combinaison of both pictures by superimposition in PSP to gray scale Final : colorization GIMP2 (Map from another previously colorized image)



Mar 3, 2015 / Testing another drifting technique with the ASI174MM, the PST-DS and eyepiece projection (MARK III 8-24 Hyperion zoom) @ 16 mm

Technique today was to start dead center (were all the activity sits then best resolution there) and make alternate up and down moves to cover the full Sun for a total time of 90s.
Frames captured=2505 File type=SER Binning=no Bit depth=16bit ROI=1936x1216 FPS (avg.)=27 Shutter=10.00ms Gain=400 HighSpeed=on AutoExposure=off Gamma=50 (off) SoftwareGain=10 (off) Brightness=1 USBTraffic=60

FEB 24, 2015 15:40:33 UT / Testing the ASI174MM with the PST-DS and 16 mm eyepiece projection (MARK III 8-24 Hyperion zoom)

Poor conditions: End of afternoon low Sun (15° only), hazy, (it rained hard just before that's good !), just a single clearing, not enough time to make a nice focus adjustment and refine all parameters !

FireCapture v2.4.07 beta Settings
Camera=ZWO ASI174MM Frames captured=999 File type=SER Bit depth=8bit ROI=1936x1216 FPS (avg.)=24 Shutter=40.00ms Gain=180 USB Traffic=60 HighSpeed=on Limit=40 Seconds Sensor temperature=29.4 °C
Standard capture (no drifting)
Processing AS!2 Color in GIMP2 North up with Irfanview.

FEB 11, 2015 The second longest structure of the Solar System

A filament of magnetism almost 1,000,000 km long and it is active !!

PST DS, Camera=ZWO ASI120MM-S, 30s movie every 300s done (as all captures here) with Firecapture 16 bit mode in autorun.
First registration done with AS!2 in surface crop mode, each resulting PNG batch renamed with TotalCommander
and the whole given to RegiStax5 in order for final alignment and ouytput the final AVI. Fps changed from 300 to 30 with VirtualDub.

PST DS, Processed with RegiStax5, Wx, GIMP2. See that for filaments a PST-DS gives much better results than a PST-1S !!

FireCapture v2.4 beta Settings
Camera=ZWO ASI120MM-S
Frames captured=4001
File type=SER
FPS (avg.)=16
SoftwareGain=10 (off)
Limit=240 Seconds
Sensor temperature=19.2 °C

PST 1S, Processed with RegiStax5, Wx, GIMP2. FLAT ... See this page for learning how to make PST Flats !!

FireCapture v2.4 beta Settings
Camera=ZWO ASI120MM-S
Frames captured=7426
File type=SER
FPS (avg.)=30
Sensor temperature=17.0 °C
Below live screencapture with PST DS...

New : FEB 3, 2015 Best today resolution with a higher Sun as captured in Jerusalem (31.7° Lat, a -16° difference) !

PST 1S, ZWO ASI120MM-S camera.
Processed with AS!2, Wx, GIMP2. I had not a mount good enough to make a full Sun as good with Registax5 but you can see it here nevertheless...

JAN 14, 2015 Very good resolution despite very very low Sun ! See data.

I had to clean the capture a lot ! See the moves as screen capture (click to download AVI) ...

DEC 9, 2014

Despite rather thick high clouds, already the best single movie image I ever made at the main focus of a PST ... 2 processing :

This image is the GIMP2 colorized version of this gray-scale one and is the result of a single 80s .SER 16 bit video in simple stack.

Other version with more wavelets ...

Here are the details :

FireCapture v2.4 beta Settings
Camera=ZWO ASI120MM-S
Frames captured=2336
File type=SER
[16 bit mode]
FPS (avg.)=29
SoftwareGain=100 (off)
Gamma=50 (off)
Sensor temperature=20.0 °C

As the Sun disk is larger than the height of the sensor, I made a drifting movement at slowest speed in AD during the capture
(camera rotated at 90°, AD moves being easier to reverse than DEC ones)

You can see how in the divx placed here.
The movie was then registered with RegiStax5 with a 256x256 alignment square placed on a small sunspot near the center (always visible) and
stacked using "expand to maximum imagesize". This way produce an automatic "mosaic" !

Wavelets and gamma were applied with a new software (Wx in development) and colorization was in GIMP2 using Map from another image...

PST - ZWO ASI 120 Dural adapter done by a friend !!

The PST black eyepiece holder (screw removed !) is going all the way inside the adapter until touching the camera body ...


13 NOV 2014 New DIY and COMPARO !

Ok, one shot (color) with the Canon EOS has some interest (see way lower in this page) but we know it is far nicer with a B&W camera !

Ok, I do nice one shot picture with the STL11000M (below), my Fluorite 102/900 refractor at ~ FD 14 plus Coronado SM/T 90 and BF30 ...

Of course click on image for full size !
As used resolution : 1.3" / Pixel

...but I am

... looking for a cheaper solution !

Moreover with the STL I can download 1 picture per 30s at full resolution or 1 picture per ~10s at bin 2x2 resolution so I doubt the result is free of effects of turbulence !

We know that registering best frames of a video is the way to go but the problem is to get single shots of the the whole solar disk otherwise we have to do mosaics !

Mosaics of 10 fields x 15s are looking great but not easy to do - especially with the PST - and time consuming ...

The sky was lightly cloudy when I did this experiment but I wanted to try today all the tricks I had in mind ...

I will start with the latest one ...


A] Capture with the PST and ZWO ASI-120MMM-S camera (1/3") and no barlow !
Sensor: 1/3" CMOS AR0130CS(Color) / MT9M034(mono) 1.2Mega Pixels 1280x960 Pixel Size: 3.75µm Exposure Range: 64µs-1000s
As used resolution : 1.9" / Pixel

The adapter is removed and the camera hold on the PST without screw ... This permits to have focus easily !
We get most of the Sun Disk !
Black tape is to get rid of spurious light. Later a metal dedicated adapter will be made.

Discussion : What is the interest compared with case D as the former gives a better resolution (1.63 " / pixel) ??
Answer : the QHY5 (PL1-M) camera will capture at about 5 - 7 fps only ... with the ASI120-S we work at 77 fps !!
This will make a huge difference for registration !!

Click on pictures for 100% size ...
As you can see on the width side there is plenty of room event for very large prominences. On the height side a bit is missing...
Here, the trick to get all the Sun in one picture without doing a mosaic is to use this capability of RegiStax (also Autostakkert but not here - I wont show the bad result :) -
to expand the stack to maximum size.
Then I only had to make slow (tracking speed) ups and downs during the 60s capture to capture about half of the frames with the top of the Sun largely visible then same for the bottom ...
In RegiStax5, I choose the filament (could not take something else with the clouds coming) at the bottom inside a 256 pixel square box and align.

Here is the resulting registered / stacked picture after wavelets and some processing (gamma, stretch) in RegiStax6 :

Absolutely no problems !! The Sun is looking good, no streaks, no intensity problems ... I am excited to do the same on a next sunny day !

B] Before that the attemps was with a PL1-M (QHY5) camera (larger sensor 1/2") placed the same.
1.2Mega Pixels 1280x1024 Pixel Size: 5.2µm Exposure Range: 1ms-5s
As used resolution : 2.7" / Pixel

The sky was a bit clearer then I used the PST-DS ...

The Sun sits well in the middle of black space ! Here is the result of a 120 frm AVI processed with RegiStax5 then wavelets in RegiStax6 :


C] Still before that the attemps was with a PL1-M (QHY5) camera (larger sensor 1/2")
with a short 2x barlow ( PST-SingleStack)
1.2Mega Pixels 1280x1024 Pixel Size: 5.2µm Exposure Range: 1ms-5s
As used resolution : 1.34" / Pixel

The sky was a bit clear

As you can see the Sun does not fit inside the FOV of the camera neither in width nor in height...

I made a mosaïc with Microsoft ICE. Click on image for full size !


D] Still before that the attemps was with a PL1-M (QHY5) camera (larger sensor 1/2")
with a very short 1.6x Magni-Max AC555 barlow ( PST-oneS)
1.2Mega Pixels 1280x1024 Pixel Size: 5.2µm Exposure Range: 1ms-5s
As used resolution : 1.68" / Pixel

The sky was almost clear

As you can see the Sun does fit in the width FOV of the camera.

I made two 1 min AVis then after AS!2, a mosaïc with Microsoft ICE. Click on image for full size !





Adapting a Canon EOS 40D to a PST for whole disk + prominences high resolution images (see example at bottom of page) !

In case you have no access to a lathe to make a dedicated adaptor...

See also Chap. III for webcam adaptation !

At end of page see a reader's comment...

I) My original method with a Meade Barlow Lens :

Material needed :


Lets go !

You have to find the exact model of 2x barlow in 3 pieces (see above) !


All barlows don't work !

Most of them are too thick, I tried many !... you will never reach focus !


We will use only the lens assembly with the black ring on the top...

Separate the lens assembly (easy !) ...
Insert some Scotch tape in the 1"1/4 tubing which goes in the T-adapter
Gently insert the lens assembly for a few mm ...
Cut the excess of tape...

Put the adaptor on the EOS.

Put the assembly in the PST eyepiece holder.

The bottom barlow lens holding should touch the bottom of the eyepiece holder. If not you adaptation is too short !

Now push (via the camera T-ring) the adaptor into the Coronado eyepiece holder until the top of the 1 1/4" tubing is completely inserted ! If you still see some 1 1/4" tubing, you have to shorten it a bit (but not too much ...remember the barlow lens should touch the bottom !) and redo the insertion.

If you have still focusing problems, you can eliminate by filing some of the thickness of the top wider ring, mine (seen here in brown-yellow color) is exactly 2.6 mm.

In my case the total length after the T-ring is 32.12 mm (see also image below).

Take the lens-adaptor assembly out and put some nail cream to fix everything !

The adaptor is done !

I have even a very very little bit of extra focusing length :)

The Sun looks like this on the liveview screen...

Fine focusing at 10X on the rim of the Sun...

If I turn all the way out the PST knob, I reach even a very small bit beyond focus !

Single image example (but only here jpg quality ... for nicer images, batch-processed with Registax5 go here) :

II) Straitghforward attachement proposed by Philippe TROUSLARD, France
with a very good Orion Barlow lens :

Note : I seems that a piece of the puzzle was missing ... I am not 100% sure (please confirm to me via email) but you should install part 1
of the Basic Camera adapter shown below between the usual M42 threaded T-ring and the bottom of the Shorty plus barlow
(taking the place of part 2) !

and result :


III) Barlow + Webcam + PST

A nicely working set :
FOV and quality (single image) obtained ...

Reader's Comments ...

Michael J Jenkin
Senior Systems Engineer

Thankyou for your mod page at
I purchased a MEADE Series 4000 #126 2x Short-Focus Barlow (1.25") from ebay and it has a different front element to the one in your images.
It is still removable and whilst I am still playing, I feel I have gotten focus.
I ended up cutting my T adaptor back to 20mm and getting a knife and trimming back the threads and side of the front element assembly of the shortfocus
barlow lens. I found my best results were not to combine the element and T adaptor. I simply drop the front element into the PST, and then plug in the camera and
T adaptor. The T Adaptor is then just for grip and steadying the camera. It seems to work well.
I have focus on my Canon 450d but at 10x I can't get focus. I think this has more to do with how I am doing it and need to use a laptop.
Anyway, it works well.