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Vienna at Night – Special Shots.

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During the last year I was able to take some shots of Vienna at night. A very nice spot is the Karlskirche. With my EOS 600D I took some shots at once, but I had the problem that I had no tripod. So I took some pictures with the hand and ISO 3200. But because of the APS-C, I had a lot of noise and used the stacking technique and stacked tree pictures into one. This technique is really nice for people that have a small sensor size and also want to have low noise pictures.

Karlskirche in Vienna. Taken with EOS 600D and ISO 3200 free hand

Karlskirche in Vienna. Taken with EOS 600D and ISO 3200 free hand

I also took some HDRs of the Karlskirche an tried different setting to the algorithm. I’m not really satisfied with the Adobe Photoshop algorithm. It looks somehow false and not nice. Next time I will evaluate the programs Photomatrix from HDRsoft and also the open source alternative Luminance HDR. I’m really looking forward to test  both programs and their performance. Anyway, here are the results of Photoshop HDR after a really long time of trying. Most of the times I ended up with monochrome settings but this is also boring all the time.

The Karlskirche in Vienna. HDR Shot out of tree pictures with +- 2EV.

The Karlskirche in Vienna. HDR Shot out of tree pictures with +- 2EV.

The Karlskirche in Vienna. HDR Shot out of tree pictures with +- 2EV.

The Karlskirche in Vienna. HDR Shot out of tree pictures with +- 2EV.

I also made some HDR pictures of the Musikverein in Vienna. The main problem was that I had a bit of rain. This can be seen in the dark areas where the water drops form some halos.

Vienna Musikverein. Assembled out of three pictures with +-2EV.

I also really like long exposure photographs. They show you a surreal picture of the real world. Also they are easy to made. You just need a nice spot and a long exposure. The camera type, small sensor sizes and weak ISO performance doesn’t matter, as well as lenses with aperture numbers above the f/3. These pictures below are taken with a EOS 600D and the stock 18-55 mm IS II.

The picture below is stacked out of five pictures with ISO 100, f/22 and 10 s of exposure. The camera was the EOS 600D with the 18-55 mm IS II. I stacked the picture with Photoshop with the Bright Color mod for each layer.

Light Streaks in Vienna.

Light Streaks in Vienna.

This picture is also stacked, but i used 40 pictures for stacking. The Camera settings were f/11, ISO 200 and 2.5 s exposure.

Highway A22 near Vienna.

Highway A22 near Vienna.

The picture below is also stacked but for this I used the the Vivid Light settings. The camera settings were f/22, ISO 100 and 15 s of exposure.

Light Streaks in Vienna near Karlsplatz.

Light Streaks in Vienna at Karlsplatz.

 A normal long exposure is the picture below. This was taken with the EOS 6D and the Sigma 50 mm 1.4. I did not stack them, just used some Camera RAW Settings.

Long Exposure Capture at Liechtenwerderplatz in Vienna.

Long Exposure Capture at Liechtenwerderplatz in Vienna.

Also the following picture is not stacked, just reworked with some Camera RAW settings. This time also the camera was the EOS 6D and the Sigma 50 mm 1.4.

The Währinger Gürtel an Night.

 

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Shutter Speed Calculating for Night Sky Photographing

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Night Sky at the Alois Günther Haus

Night Sky at the Alois Günther Haus

Recently I wanted to improve my skills in night sky photographing. So I opened the PC and asked Google a lot of questions. I was reading a lot about shutter speed, focal length and exposure adjustment. A very good site I found was How to Photograph the Milky Way of the site www.lonelyspeck.com. They created a very good tutorial and answered many of my questions. They also created the Milky Way Exposure Calculator, witch lets you calculate how a lens may perform on your camera. For ranking the lenses they calculate a score, basically from the physical parameters of the lens. I agreed with the majority of the parameters, but I was wondering if the slowest possible shutter speed is maybe a bit inaccurate.

In night sky photography the shutter speed is mostly longer than 5-10 s or even more. Without a tracking device the stars will move over the sky and produce, depending on the shutter speed, streaks on the picture. But we want actually a clean image of the stars. So what we need is a lens with a short focal length and an aperture which should have less than f/2 to gather a lot of light. The basics can be checked in the links above. Anyway, the rule of thump for the shutter speed, 500/focal length, seems a bit inaccurate and, as stated there, also not completely usable for APS-C cameras. So I started to think, how can this be solved better…? I was drawing some sketches and made some calculations and concluded: there might be a better and more accurate way: I started to research about what information are available for all lenses and cameras. I concluded that the sensor size and the focal length is available in any case. The angle of view was not all the time available or I just couldn’t find it. Anyway, with the sensor size and the focal length we can calculate the angle of view with the following equation:

alpha = 2 * \arctan {\dfrac{d}{2 * f}}

In this equation, d is the diameter of the sensor and f is the effective focal length. Since f is depending on the focus, the focal length F of a 50 mm lens is only 50 mm when set to Infinity. Since in astro photography we use only the infinity setting we can assume f = F. So we can also calculate the horizontal and vertical angle of view for a lens. In this case I will just use the stock Canon EF-S 18-55mm 1:3.5-5.6 IS II on a EOS 600D with 18 MP as example. Why we need the horizontal and the vertical angle of view, will be pointed out later. With the pixel count on the camera we can now calculate the angle to pixel ratio. The 600D has 18 MP with a 3:2 ratio. This leads to a pixel count of 5.184 px by 3.456 px. The pixel to angle ratio is calculated by α / Σnpixel. The diagonal pixel count is just calculated by Pythagorean theorem.

  • Vertical AOV: αv = 27°; Pixel to Angle Radio = 0,0185°/px
  • Horizontal AOV αh = 37.4°; Pixel to Angle Radio = 0,0164°/px
  • Diagonal AOV αd = 46.8°; Pixel to Angle Radio = 0,0153°/px
The night sky can be seen as a cylinder rotating around the camera.

The night sky can be seen as a cylinder rotating around the camera.

The next assumption we make is that the sky is rotating around the world. I know that some people will now say “NO! Galileo was very clear with that!”. Yes its not true but since we focus anyway on infinity and the sky is more more less a flat area for the lens, this is ok. This lead so my next assumption. The sky is not a sphere, its like a cylinder. The picture demonstrates this assumption. The cylinder rotates with the angular speed of 360° per 24h or 0.00417 °/s. Depending on the pixel to angle ratio we can now calculate the minimum shutter speed. In case of my 18 mm focal length the numbers are very small and and seem not right.

  • Vertical max. Shutter Speed: 4.4 s
  • Horizontal max. Shutter Speed: 3.9 s
  • Diagonal max. Shutter Speed: 3.6 s

But this is only the half truth. Since the stars are not only one pixel big, we can use a threshold. For example a threshold of five pixels will give us five times the shutter speed. In my test, five pixel threshold was mostly ok and not really visible. Somebody who wants to have more clear pictures can reduce the threshold.

  • Vertical max. Shutter Speed: 22 s
  • Horizontal max. Shutter Speed: 20 s
  • Diagonal max. Shutter Speed: 18 s

I’ll program a calculator using javascript in the near future and upload it to this website. Stay tuned!

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WP Parabola Theme and Google Structured Data

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While setting up my Google Webmaster Tools I ran into the problem that WordPress in combination with the nice Parabola Theme is not 100% conformed the Google expectations. I saw some errors on the page and tried to figure out what exactly triggers this error. On the overview page I found these entries.

google webmaster tools failure

 

The crawler of Google searches for the hatom information on the page. For my page it finds most of the tags, like the author, the title, the content and also the publish date. But it searches also specific for the field “updated”. The failure occures more often on category sites, because there are more entries, and only once on the simple post.

After some research I found a solution by adding  some simple lines to some files in the theme. But because you still want to update your theme, the best way to edit your theme is by adding a child to the normal theme. This is basically done by creating a new folder under /wp-content/themes/ with the name %theme-name%-child. In my case this was “parabola-child”. After creating a child folder, a file named sytle.css has to be created in the folder. The basic setup is in my case:

/*
Theme Name:     TL-PHOTOGRPAHY
Theme URI:      http;//www.tl-photography.at
Description:    Customize Parabola
Author:         Thomas Leber
Author URI:     https://www.tl-photography.at
Template:       parabola
Version:        1.0.0
License:        GNU General Public License v3.0
*/

@import url("../parabola/style.css");

 The most important line is  Template: parabola. This tells WordPress that this is a child of the Parabola theme. All steps can be found here. WordPress will now load all files from the child folder and override the corresponding files of the main theme. Basically you can copy a file like header.php to the child theme and edit it. The rest of the files will be loaded from the main theme. In our case I searched the content.php and found a link to the parabola_posted_on() in includes/theme-loop.php function. This function provides the meta information of the post and can also be used to write the additional tags to the page. Unfortunately, after i copied and edited my file, WordPress was still loading the main file. This seems to be a bug or i did simply something wrong, ten times or so… Anyway, I decided to change in this case the content.php file. I copied the  snipped from here and added the “hidden=true” to prevent that information from rendering to the screen.

<h2 class="entry-title">
<a href="<?php the_permalink(); ?>" title="<?php printf( esc_attr__( 'Permalink to %s', 'parabola' ), the_title_attribute( 'echo=0' ) ); ?>" rel="bookmark"><?php the_title(); ?></a>
</h2>
<span class="post-date published" hidden="true"><?php the_time( get_option( 'date_format' ) ); ?></span>
<span class="post-date updated" hidden="true"><?php the_modified_time( get_option( 'date_format' ) ); ?></span>
<?php cryout_post_title_hook(); 
?><?php if ( 'post' == get_post_type() ) : ?>
<div class="entry-meta">
  <?php parabola_posted_on(); 
    cryout_post_meta_hook();  ?>
  </div><!-- .entry-meta -->
<?php endif; ?>

After this modification, the category pages will have the hidden information and Google will crawl these pages without errors. But the single post will still have this failure. So again, after some searching, I figured out that this is related to the file single.php. So I added the same two lines there.

<h1 class="entry-title"><?php the_title(); ?></h1>
<?php cryout_post_title_hook(); ?>
<span class="post-date published" hidden="true"><?php the_time( get_option( 'date_format' ) ); ?></span>
<span class="post-date updated" hidden="true"><?php the_modified_time( get_option( 'date_format' ) ); ?></span>
<div class="entry-meta">
<?php parabola_posted_on(); cryout_post_meta_hook(); ?>
</div><!-- .entry-meta -->

 google_webmaster_tools_failure_detailIt seems that the theme also deliverers wrong data to the crawler when showing single posts. In the picture on the side,it is visible that it writes for the bookmark the date and not the name of the post. But i was fine with the result until now. Maybe i’ll fix this later or write a bug report to the programmer.

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Christmas Market

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The last weeks the Christmas markets of Vienna were calling with punch, food and some nice scenery.  When I went there I had in mind to make great scenery pictures of small stands with the merchant in front, but then I was thinking, can I photograph them and post the pictures here without permission? Then I decided just to photograph the outlays and the bits and pieces. After I looked at the pictures I realized that I really like near distance pictures and macros. So, again a post in the macro section. I used only my Sigma 50 mm F1,4 EX DG HSM lens. The smallest focus distance is only 45 cm, but the focal length of 80 mm (due to the APS-C sensor size) is enough to have a nice projection scale.

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Canon Hand Strap E2

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Since I hold the camera always in my hand while sightseeing or photographing and I simply don’t like the neck strap, i wanted to have a Hand Strap. Canon offers its own Strap with the Canon E2 Hand Strap. I’m using it on my EOS 600D. It is pretty good manufactured, very adjustable and seems durable. BUT, with my hand size (i would say, medium?) the camera is usable, but not so well usable. You can reach all functions on the back with one hand and also the trigger is good reachable, but adjusting the exposure or the aperture can be a bit like gymnastics for your fingers.  I don’t want to say its not worth the money, because if you use it on a 5D MKIII or a 7D it fits very well, but  for the 600D its not perfect.

E2_Hand_Strap_2

Hand Strap E2 on EOS 600D, side

E2_Hand_Strap_4

Hand Strap E2 on EOS 600D

E2_Hand_Strap_3

Hand Strap E2 on EOS 600D,

E2_Hand_Strap_1

Hand Strap E2 on EOS 600D, side

 

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EOS 600D

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2014-12-04 15.45.30

EOS 600D

The first cam i bought for my self was the EOS 600D. This DSLR, also known as Rebel T3i or Kiss X5, was my first choice not because of the technical specs rather than that is was cheap and a Canon. The decision to use Canon was made by the two facts that a lot of friends have Canon, so i could borrow some equipment, and the availability of Magic Lantern, but more about that later. I bought it with the kit lens, EF-S 18-55mm f/3.5-5.6 IS II and nothing more.

Handling

I was surprised by the weight of the cam, it is really light and relatively small. I was using it on the mountain, at some hiking tours and also city trips and the weight was not too much at all. The movable screen is really nice and is a feature that i would miss on cams like the 5D MKiii or the 6D. I mainly used it while making time lapses, but also in every other condition it is just a nice to have. I really miss this feature on my 6D. To avoid the moving of the tripod i didn’t use the full size of the pod and tried to mount the cam near the ground. So the wind would have a smaller effect on moving the cam. But this has the disadvantage that, if u point with the cam to the sky, the LCD is really not readable. With the LCD of the 600D this is no problem at all.

Technical Specs

The Sensor is a CMOS APS-C with 18 mega pixels. The cam can record 1080p, but i never really used video recording. Up to ISO 1600 the pictures can be rated as really good but over ISO 3200 the noise becomes really visible (For further reading – Understanding ISO). This is one of the biggest disadvantages, especially with night photographing or low light situations. I personally try to avoid more ISO than 1600 with this cam. Another disadvantage is that, if u ever want to shot a lot of pictures in a row, you have to switch to JPEG. The 600D is only capable of shooting 6 RAWs in a row or 34 JPEGs. I used this one two times right after i bought the cam, noticed this is not the strength of the cam and never used it again.

Magic Lantern

A nice “feature” for all Canons is Magic Lantern, an open source project for an alternative EOS Firmware. I was searching before i chose a camera especially for time lapse photography and sky photography. After some google sessions and approx. 1 million forum posts I found Magic Lantern. It enables a lot of features on all EOS Cameras which are normally just for the higher price league of Canon. In my case the intervalometer in combination with an automatic exposure adjustment attracted my attention. The “holy grail” of time lapse photography, the transition from day to night and vice versa in all EOS cams… nice! The firmware can do a lot of more things and you will probably need one week to explore all of them. The installation is really simple:

  • Check for a full battery and be aware that you are doing this at your own risk! Read the instructions provided with the downloads if you are stuck. 
  • An SD/SDHC/CF card with 32GB or LESS. You can still use larger cards later.
  • Download the OLD version 2.3! LINK
  • Extract the old version of ML and copy it to the ROOT folder of your SD. It is a folder named ML and two file: autoexec.bin and, in the case of a 600D, the file 600D-102.fir. There are also other files for other models but you don’t need them.
  • Now your camera have to be flashed with the new firmware. (Actually, it’s not a firmware, it just sets a flag that the camera can boot from the SD card.) For this power on the camera with the SD card inside and flash the firmware from the Canon menu.
  • Wait for the progress to be done.
  • Now your camera has the latest ML Version installed. Move on if you want to use the cutting edge Nightly Builds.
    • First go to the magic lantern download page.
    • Select the 600D there. Make sure your have the right firmware version! Is there is written 600D.102 then your 600D should have 1.02 firmware. Check that in the Canon menu on the camera.
    • Download the file and extract it.
    • Copy all contents to your SD card, overwrite the old files!
    • Power on the camera.
    • Done.

The old firmware has a nice mode for time lapsing sunset and sunrise, the bulb ramping mode. It simply ramps really smoothly the exposure over time and adjusts the brightness. I tryed this several times and was really impressed by this feature. On the downside, LRTimelapse will not work with the holy grail workflow there.  The Nightly Build will give you the option to use aETTR to create time lapses that can processed by LRTimelapse.

I think the EOS 600D is one of the best starter cams and in combination with the stock lens it is also very usable in common situations.

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Autumn

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Today we went to Belvedere and the Botanic Garden in Vienna. Because of the massive amount of people, disturbing every picture, I concentrated on macros and some plants.

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Lange Nacht der Museen

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Last weekend was the “Lange Nacht der Museen” in Vienna. For 13€ you get free entrance to mostly all museums in Vienna. We decided to give the Kunstkammer a try. As usual, in the museum was not a lot of light and a lot of people. But my Sigma 50mm 1.4 could deal with both. The guys in the background are blur and with 1.4 you get a lot of light in the sensor. Yeah, I know with a full frame it would be better. Lets see next year with the 6D… 🙂

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