So, lately I've been on a telephoto lens learning curve; after the
300mm prime, I said to test a zoom lens. As I found the prime
reasonably easy to adapt to (compared to shorter focal length lenses),
I thought that a zoom (heavier, bigger) will be the same.
Oh, I was wrong. My keeper rate for the first outdoors test was quite
bad around 50% only, which (when talking only about focus/sharpness)
is much below my standards.
I started easy; some close or medium range shots, nothing special:
But then, moving to further distances, things became less
straightforward. Shooting two pictures each time meant that usually
one of them was sharp, but the other not.
I got really confused at this step; the shutter speed was 1/2000s and
I also had VR on; either VR was unneeded (i.e. contributing blur
instead of helping) or something else was going on. After much head
scratching, I think it's a combination of the following factors:
- shooting at long range; for the pictures I'm talking about, the
subject was between 800m and 1.2km; at this range, haze and
atmospheric disturbances start to play a role.
- lens is heavy 2.3kg and adding the camera (1kg) it means that I was
hand-holding 3.3kg, which is much more than I'm used to; the focal length
of the lens, at that distance, means that any small movement
(rotation or shift) translates into significant subject movement,
especially when viewed at 1:1 magnification on a 36Mp body.
- there might still be some interplay between VR and shooting at this
shutter speed, although not sure.
So, for such style of shooting, I need to train more both photographic
technique and arm strength at the gym In the meantime, it is
possible to get such shots reasonably sharp, for example this picture
of the (start of the) Alps taken from what is technically still Z rich
city:
I'm happy with the detail (at this distance), however I was not able
to correct the colour due to the haze between me and the mountains;
note that the trees on the bottom of the distance were not near me,
but on the next or after-next hill. This picture confirms that with
more practice things will get better.
Coming back to shorter distances, and shorter focal lengths, things
are looking better. We were passing somewhat near some people playing
with RC-controlled planes not near enough to hear them, but near
enough to see the plane quickly flying. Switched camera quickly to
AF-C and Dynamic-21 focus, and - to my surprise - I was able to
capture four good pictures, two so-so and four more clearly out of
focus. But, for such a heavy length, hand-held and on the short
notice, I was happy; the first picture is one of the so-so ones, but I
kept it as I like the way the propeller is seen. All pictures at 290mm
plus some cropping, 1/1250s, ISO between 900 and 1800, f/5.6 (i.e wide open):
From this exercise, the conclusion is that the lens is OK-ish for
tracking, although the not-so good keeper rate tells me that I need to
be careful; I'll have to see how a subject moving not left-right, but
instead approaching or moving away from the camera would be tracked.
But enough pictures of small planes. At 500mm, but still somewhat
close, trees:
At this step I'm starting to wonder if stopping down a bit would help
with the sharpness; I'll have to test that in the future.
Walking some more, finally a bird in flight; one of the hopes when I
took the camera/lens out was that I'll see some birds, but this was
the first. 500mm, heavily cropped, but quite good result for myself
(same autofocus settings as before):
The only problem here is, as always with crows (I think these are
crows), is the black bird against the light-blue sky (not even strong
blue), which means the picture has a high dynamic range; recovering
the shadows on the bird is difficult. But in any case, it's clear the
lens can deliver, if the photographer is good.
Next, a helicopter was gracious enough to pass by (pretty close):
Two minutes later, it was quite far, but since it was going in the
direction of the Alps, it gave the opportunity for a nice shot:
This picture is less sharp, but still I like it due to composition;
not successful on small screens though, only if you see it full
screen. Light is very difficult though and about 10 seconds earlier
would have been even better (more separation between the helicopter
and the mountain).
And since we're talking about planes, let's see a plane at 500m,
directly overhead, and quite high:
This picture (@500mm, cropped, 1/2000s) has the most detail of a plane
flying high enough to have trails (not sure how to estimate, but at
least 5km, maybe more around 7-8 I'd say) that I ever took. So yes,
the lens can deliver, but it's not easy. This shot, being shot more or
less straight up, had the least distance through low-altitude
atmosphere, so it has less problems compared to the mountains
pictures. It's still not really sharp (lens wide open), but the amount
of detail I'm sold
And to finish on a more close note:
A long focal length lens allows one to get "close" without getting
close, which means animals are not disturbed. The first picture with
the cat (not shown) had the cat less alert; ears not fully up,
although eyes were still seeking; this picture shows it fully alert
and concentrated, like it was a wild cat hunting for its survival, and
not a city cat, out just for fun.
So, summary:
- lens is nice (optically), although fully open (f/5.6) and hand-held
and at long distance it doesn't yet give me full satisfaction; I
will need to improve my technique and learn how to properly handle
it.
- in combination with a high-megapixel body (D810), it allows fun
although pointless feats; pointless doesn't stop hobbies, though
- I need to go to the gym; not "more often", just start going!
All the best to everybody for the coming holidays, and thanks for reading.
This week I'll be mostly doing drive-by bug-reporting.
As with last year we start by using the Debian Code Search, to look
for obviously broken patterns such as "system.>./tmp/.*"
Once we find a fun match we examine the code and then report the bugs
we find. Today that was stalin
which runs some fantastic things on startup:
Again one week has passed and there has been some progress on 
The Software Freedom Conservancy is currently running a 
# Copyright (C) YEAR Free Software Foundation, Inc.
# This file is distributed under the same license as the PACKAGE package.
# FIRST AUTHOR , YEAR.
#
#, fuzzy
msgid ""
msgstr ""
"Project-Id-Version: PACKAGE VERSION\n"
"POT-Creation-Date: 2015-12-21 15:00+0100\n"
"PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n"
"Last-Translator: FULL NAME \n"
"Language-Team: LANGUAGE \n"
"Language: \n"
"MIME-Version: 1.0\n"
"Content-Type: text/plain; charset=UTF-8\n"
"Content-Transfer-Encoding: 8bit\n"
#. type: Title #
#, no-wrap
msgid "I want your input"
msgstr ""
#. type: Plain text
#, no-wrap
msgid "\n"
msgstr ""
#. type: Plain text
#, no-wrap
msgid "\n"
msgstr ""
#. type: Plain text
msgid "You want to share an opinion with me, or raise a question?"
msgstr ""
#. type: Plain text
msgid "Great, please do: I love exchanging opinions and ideas."
msgstr ""
#. type: Plain text
msgid ""
"You can [contact me discretely][]. Please consider, however, to speak in "
"public instead, allowing others to benefit from our exchange."
msgstr ""
#. type: Plain text
msgid ""
"Don't worry if it is interesting to others - the World is big and someone "
"somewhere always cares!"
msgstr ""
#. type: Plain text
msgid "[contact me discretely]:"
msgstr ""
#. type: Title ##
#, no-wrap
msgid "Email - encourages reflection"
msgstr ""
#. type: Plain text
msgid "Post to a public mailinglist."
msgstr ""
#. type: Plain text
msgid ""
"If uncertain that I am subscribed to the list, or if you want my special "
"attention (but think twice if that's really needed!), add my [private "
"mail](mailto:dr@jones.dk) as cc."
msgstr ""
#. type: Title ##
#, no-wrap
msgid "Chat - more casual"
msgstr ""
#. type: Plain text
msgid ""
"I am also [reachable via chat][]. Chat is nice for shorter "
"questions/comments, and when you need to discuss what you want to say at "
"all."
msgstr ""
#. type: Plain text
msgid "[reachable via chat]:"
msgstr ""
#. type: Title ##
#, no-wrap
msgid "Blog - best for reuse"
msgstr ""
Umm. Somehow I thought this would be easier than learning about
live-build. Probably I was wrong. There are probably many better
tutorials on the web.
Two useful observations: zeroing the key can eliminate mysterious grub
errors, and systemd-nspawn is pretty handy. One thing that should have
been obvious, but wasn't to me is that it's easier to install grub
onto a device outside of any container.
Find device
TeleLaunchTwo A Smaller Wireless Launch Controller
I've built a wireless launch control system for NAR and OROC. Those
are both complex systems with a single controller capable of running
hundreds of pads. And, it's also complicated to build, with each board
hand-made by elves in our Portland facility (aka, my office).
A bunch of people have asked for something simpler, but using the same
AES-secured two-way wireless communications link, so I decided to just
build something and see if we couldn't eventually come up with
something useful. I think if there's enough interest, I can get some
boards built for reasonable money.
Here's a picture of the system; you can see the LCO end in a box
behind the pad end sitting on the bench.
What happened in the 
Portability toward other systems has been improved: old versions of GNU diff are now supported (Mike McQuaid), suggestion of the appropriate locale is now the more generic 
For the last week I have been stuck in England. For the vast majority of that time, I've had nothing to do except work on Debian and this blog post documents some of the things I worked on.
Obviously spending a whole week on Debian, there's going to be some packaging involved. The following packages got new versions in unstable this last week:
In September, The 
After a short hiatus, a new version of the (wonderfully useful, if I dare say so ;-) 
Dear lazyweb,
TL;DR version
Why does