so I tried to take pictures of a house and the night sky, but everything came out very blurry no matter what I used  I shot at 30 sec exposure, F 3.5, ISO 3200 on a tripod using remote
I was shooting the lighting of the city that is visible at the top of the trees if you shoot landscape.  No matter what I do, the image is blurry. What have i done:   ISO 100 Manual focus towards infinity Using a tripod Using really sharp prime &amp; good camera   Basically, everything I could. The only example i have is here, but it is not good, because image is underexposed:    The main question: Why can't night photographs be as sharp as daily photographs (with approperiate exposure times of course)?
$$e^{i} = e^{i2\pi/2\pi} = (e^{2\pi i})^{1/(2\pi)} = 1^{1/(2\pi )} = 1$$  Obviously, one of my algebraic manipulations is not valid. bashrc lazy substitution How to integrate OpenCV Manager in Android App How can I change the Windows 7 Logon Screen wallpaper? is a one-by-one-matrix just a number (scalar)? I was wondering. Clearly, we cannot multiply a (1x1)-matrix with a (4x3)-matrix; However, we can multiply a scalar with a matrix. This suggests a difference.  On the other hand, I was, for example, in an econometrics lecture today, where we had for a (Tx1)-vector $\underline{û}=\left( \begin{array}{c} û_1\\ \vdots\\ û_T\end{array}\right)$:     $S_{ûû}:= \sum_{i=1}^T û_i^2$ shall be minimized. We see see that   $S_{ûû}=\underline{û}^T\underline{û}$.   Well, formally, shouldn't it be $(S_{ûû})=\underline{û}^T\underline{û}$ or $S_{ûû}=\det(\underline{û}^T\underline{û})$, to ensure that we stay in the space of matrices and not suddenly go to the space of scalars? So here, the professor (physicist) not only treats $\underline{û}^T\underline{û}$ like a scalar, but also calls it a scalar. Is this formally legit or a wrong simplification (though it does not seem to have any impact, and surely makes life easier)? Why is "chmod -R 777 /" destructive? Are split infinitives grammatically incorrect, or are they valid constructs? Mark's generosity in this crisis seems to more than make up for his earlier stinginess.   Should those sentences always be avoided, or are there cases where they are valid? Is there a way to truly delete all deleted files? I know that on the windows operating system, when you delete a file it's still recoverable.  I'd like to avoid simply paving the harddrive with zeros as I would like to keep my OS installation as is, but is there a way to truly delete files that have been previously deleted? How to connect Android with MySQL using Mysql JDBC driver Piping for loop output prevents local variable modification I'm trying to write a simple bash function that takes, as its arguments, a number of files and/or directories. It should:   Fully qualify the filenames. Sort them. Remove duplicates. Print all that actually exist. Return the number of non-existent files.   I have a script that almost does what I want, but falls down on the sorting. The return value of the script as it stands is correct, but the output is not (unsorted and duplicates). If I uncomment the | sort -u statement as indicated, the output is correct but the return value is always 0.  N.B. Simpler solutions to solve the problem are welcome but the question is really about why is this occurring in the code I have. That is, why does adding the pipe seemingly stop the script incrementing the variable r?  Here's the script:  function uniqfile {     local r=0       for arg in "$@"     do           readlink -e "$arg" || (( ++r ))      done #| sort -u    ## remove that comment      return $r } Unknown Additional Driver: Processor microcode firmware for Intel CPUs for intel-microcode After upgrading to 15.04, I have one additional driver (it did not appear in 14.10). What is the purpose of this driver and should I enable it? Why do microcontrollers have so little RAM? Maybe this is more of a perceptional problem, but it seems like microcontrollers have advanced by leaps and bounds in the last 20 years, in almost all regards, higher clock speed, more peripherals, easier debugging, 32-bit cores, etc...  It is still common to see RAM in the 10's of KB (16/32&nbsp;KB).  It doesn't seem like it could be an issue of cost or size directly. Is it an issue of complexity with the RAM controller above some threshold?  Or is it just that it isn't generally required?  Looking over a parts matrix at a popular Internet supplier, I see one  with 256&nbsp;KB for less than US$8, and then for a few dollars more you can find a few more that are ROMless, but it seems pretty sparse...  I don't exactly have a need for a microcontroller with a MB of volatile storage, but it seems like somebody might... Performing test for homogeneity of variance without samples I'd like to perform a test for homogeneity of variance in r, but I don't have samples available to test.    I have the sample mean of each group, the sample deviation of each group, and the sample size of each group(100).  Brand    ybar_i  s_i    n_i --------------------------- LowTar   9.64    .291   100 A        10.22   .478   100 B        10.77   .372   100 C        11.57   .352   100 D        13.59   .469   100   I'm thinking I should use the Levene test from Lawstat package, but that requires samples to test.  Or I think I could use the Fmax test. but that also requires samples. What happens if no one survives the Hunger Games? It is possible that the remaining last two tributes might get killed at the same time, for example, by a land mine explosion, and in that case the games will end with no victor standing.  Is there a reference in the original books as to what happens if nobody emerges victor in the Hunger Games? Does the OP of a flagged post get comment notifications if the post is deleted by mods? What does the Y capacitor in a SMPS do? "is" operator behaves unexpectedly with integers Why does the following behave unexpectedly in Python?  &gt;&gt;&gt; a = 256 &gt;&gt;&gt; b = 256 &gt;&gt;&gt; a is b True           # This is an expected result &gt;&gt;&gt; a = 257 &gt;&gt;&gt; b = 257 &gt;&gt;&gt; a is b False          # What happened here? Why is this False? &gt;&gt;&gt; 257 is 257 True           # Yet the literal numbers compare properly   I am using Python 2.5.2. Trying some different versions of Python, it appears that Python 2.3.3 shows the above behaviour between 99 and 100.  Based on the above, I can hypothesize that Python is internally implemented such that "small" integers are stored in a different way than larger integers and the is operator can tell the difference. Why the leaky abstraction? What is a better way of comparing two arbitrary objects to see whether they are the same when I don't know in advance whether they are numbers or not? Magnetic Field in the presence of a conductor I am studying for my quals and came across an old question that reads like the following:      There are two regions in space separated by an infinite conducting plane. Region 1 has a magnetic dipole of moment $\vec{\mu}$ located a distance $d$ from the plane. What is the magnetic field $\vec{B}$ everywhere in region 1?   I know that for a perfect conductor (superconductor), the normal component of $\vec{B}$ is zero–although I don't exactly know why–but I don't know if that is the case when the problem involves a "conductor" (not explicitly a perfect conductor).  TL;DR: Can anybody give me some insight about the magnetic boundary conditions of a stationary magnetic field in the presence of a conductor?  Thanks! How to change certain pages into landscape/portrait mode How can I change some pages into document into landscape mode, while leaving the others in portrait mode (or vice versa)? I am trying to understand model vs. interpretation of sentences vs. theories, with respect to a propositional calculus.  Is a model of a wff just a sentence that is true under some interpretation?   Or a set of wffs that are all true under some interpretation?   Or when an interpretation satisfies a wff (or set of wffs)?   Does it make sense to say that an interpretation is a model if all valid propositions are true? Or an interpretation being a model iff all theorems from the theory are still valid under the interpretation?