Archive for August, 2015

Venus in daytime – August 30, 2015

Posted in ASTRO on August 30, 2015 by maxpho

On a short trip to Targoviste, where I was hopefully going to catch the ISS in transit over the disc of Venus (transit duration: 0.02seconds!) I had the luck of some very good seeing conditions for a short imaging session with Venus. Unfortunately the ISS transit was a total failure due to technical problems (hard drives, focusing…) despite perfectly clear skies, and good seeing conditions.

The Venus image, resulted from a small amount of processing of the final stacked image, is presented below together with the technical details:

venus august 30, 2015

And an artificially colored version of the above:

venus august 30 color

And a step further: composition of the above image with the one from my previous post showing sunspot group AR2403 near the limb of the Sun. Hope you’ll enjoy the image!

Sun and Venus august 2015MaximusPhotographyThe above images showing Venus were posted by Deborah Byrd on the website. Thank you Deborah!


Sunspot group AR 2403 near the solar limb – August 28, 2015

Posted in ASTRO on August 28, 2015 by maxpho

It’s time to say goodbye to sunspot 2403! Tomorrow this large sunspot group will be right on the edge of the visible side of the Sun, and eventually will depart altogether.

I had to get one final image of it, so I drove a few miles from work and got my homemade 200mm F/5 Newtonian out in a corn field at 32 degrees Celsius.

This was the view that I had on the laptop screen (minus the color, added later during processing):


The above image was published on the first page of SpaceWeather on the same day it was acquired.

The same image was also posted on the website.

The equipment: 200mm F/5 homemade Newtonian working at F/15, Astrosolar full aperture filter, ASI 120MM-S camera with Baader Red filter. Seeing: 6-7/10.

And the normally orientated views, greyscale and color:

AR 2403 BW

AR 2403 COL

Hope another group like 2403 will be visible on the Sun soon.

ISS solar transit – August 26, 2015

Posted in Uncategorized on August 26, 2015 by maxpho

Today I’ve went together with my wife on a small drive a few miles west from our home to shoot a solar transit of the ISS. It’s been a while since our last ISS transit, so the event was not to be missed. Luckily enough we had light traffic, clear skies, and good enough seeing at the moment of the transit. Plus a great sunspot group (AR2403) near by.

My wife’s imaging setup was a 127mm F/12 Maksutov, while I used a 115mm F/8 APO Refractor and a 2x Barlow lens. Both with Canon 550D cameras at ISO100 and of course solar filters placed at the front of the scopes. As before, the ephemeris was computed for us by CalSky.

The images now:

ISS AR2403 Aug26Eli

ISS AR2403 Aug26Max1

ISS AR2403 Aug26MaxLARGE

Too bad the solar panels were not parallel to the Earth, so we could have had a better view of the ISS. Next time I will have to speak with some of the astronauts 🙂 The ISS looks a bit like a bird in these images.

Sunspot group AR 2403 – August 23, 2015

Posted in ASTRO on August 23, 2015 by maxpho

A new sunspot group on the Sun these days, and a new imaging session for me. After so many days of clouds and rain (it felt like months), I’ve finally got another chance at imaging the Sun. The seeing did not cooperate too much, but for a few brief seconds a clear window allowed for some fantastic views of the new group.

My equipment was the homemade 200mm F/5 Newtonian working at F/20, with a full aperture Astrosolar filter and the ASI 120MM-S camera with a Baader green filter. The seeing conditions were mostly 2-3/10, with the mentioned brief good seeing of 7/10. Only 700 frames were stacked for the images below.

The color version shows the Earth’s diameter also, just as a remainder of how small our planet really is in the Solar System.


ar2403h1335aug23MaxBWOne of the above images was posted by Deborah Byrd on the website. Thank you Deborah!

Venus at inferior conjunction – August 16, 2015

Posted in ASTRO on August 16, 2015 by maxpho

Just a few tens of hours ago, planet Venus was at inferior conjunction, meaning that the planet was between the Sun and the Earth. This means that the angular diameter of Venus was at it’s maximum, near 1 arc-minute, or around 1/30 from the apparent diameter of the Sun or Moon in our skies. This is usually very good for astro-photographers since the bigger the size of the object, the smaller details can be obtained onto it’s surface. The problem with Venus (and Mercury also) is that being closer to the Sun compared to Earth, at it’s largest apparent size the planet is only visible in the daytime. This also means that finding the planet is not as easy as looking for it at sunset/sunrise with your naked eyes and pointing the scope in that direction; in daytime you have to know the position of the planet in relation to the Sun (or if you have a GPS scope just press the GOTO function) and hope you don’t point it directly to our star…which will damage one of the sensors (either your CCD/CMOS camera, or…the eye!!!).

But after finding it, you know it was all worth the trouble…

This was the feeling that I had today while trying to capture Venus in daytime. Pointing blindly the scope to the computed position and searching the planet through the eyepiece for about 10 seconds rewarded me with a superb view of the thin crescent.

The following is an approximation of the view I had at the eyepiece at 250x through a 127mm Maksutov telescope, the image of the planet itself being the result of the session.

Venus at 250x

And now the true result, in black and white, made through some very unstable seeing conditions (generally poor):

Venus August 16, 2015

After finishing the Venus session, I’ve pointed the telescope towards the Sun (with a proper solar filter placed at the front) and imaged the two very small and apparently uninteresting sunspot groups. The granulation is discernible, but the seeing conditions, amplification factor and scope diameter didn’t allow for a clear view of the Sun’s surface.

ar 2401

ar 2400

Sunspot group AR2396 – August 11, 2015

Posted in ASTRO on August 11, 2015 by maxpho

And another session with AR2396.

This time I had some good seeing conditions that allowed a better resolution over the Sun’s surface and better details in the main spot of AR2396.

The equipment used: 200mm F/5 Newtonian at F/20 and F/50, full aperture Astrosolar filter, ASI 120MM-S camera with Baader Green filter.

The images, both greyscale and colored:

AR2396 August11b

AR2396 August11

The above images were acquired at F/20, while the one below, showing only the main spot of AR2396 was acquired at F/50.

central spot

The rather good seeing conditions (reaching 7/10 in some moments) allowed me to capture good images of the solar granulation around a few pores:

granulation aug11 b

granulation aug11

Sunspot group AR2396 – August 10, 2015

Posted in ASTRO on August 10, 2015 by maxpho

Another imaging session with AR2396. Actually today I had two sessions with this nice sunspot group, one in the morning with a 127mm F/11.7 Maksutov telescope, and another one in the evening with a 200mm F/5 Newtonian scope. In both cases the amplification factor was 3 (4500mm and 3000mm focal lengths respectively), and the camera used was the ASI120MM-S with a Baader green filter.

First, the Mak images..

A wider view, showing the limb of the Sun:


And a detailed view, with the solar granulation discernible:

AR2396 August 10, 2015

A comparison with the image from the previous day, showing the evolution of the group:

AR2396 two days evolution

And an animation of the two images:

ANIM 2DAYSThe second session was a bit better in terms of the obtained details, but the seeing and transparency were much more affected due to cirrus clouds rolling in. Nevertheless, the following are the best shots of this sunspot group that I’ve acquired so far. A wider grayscale image:

ar2396 8inch wide

And an enlargement of the above, with colors added via Photoshop:

ar2396 large

The shape of the sunspots in AR2396 made me create an animation in which I’ve superimposed the first two letters of the alphabet onto the two main spots. In solar astronomy the main spots are labeled in such way, so it’s not just an artistic impression 🙂

a to bI hope for better seeing conditions for the next solar imaging session…