The following image was rendered using 2000 samples.  The render takes about 3 mins and the image looks pretty noisy still, especially the wall of the building. I'm gonna have to render a really long animation so I would prefer to keep the samples less than 2000 so it doesn't take forever to render the whole animation.   I searched online for a solution and tried everything that was suggested in this post: .   It helped some but the noise is still present in the image. I was wondering if there are any other ways to reduce the noise without increasing the sample number (through lighting or maybe using compositor)? Any suggestions are appreciated. Thanks in advance.
I know that this question is a bit old or maybe overdone, but I'm running the latest edition of Blender and when I use the Cycles engine I get really fuzzy results and I can't find a simple, non-compromising solution to the quality.  I don't know exactly what I'm doing wrong here, but I'm sure others share my frustration.  Leaving everything in default settings, I started a new project and switched to the Cycles render.  I duplicated the cube and set colors for two Diffuse BSDF shaders, then went ahead and made walls and a floor all sharing the same diffuse shader.  I made two windows to emit blue light.  The screenshot has gaps between the walls because of the setup:  I'm aware that it's considered very incomplete and many have come to terms with some amount of noise, but is this normal?  Furthermore, with default settings or not, I can't change the amount of noise produced.  Supposedly, using "progressively refine" in the rendering tab should make it refine itself indefinitely, however Cycles only counts to 10 refines and then stops, creating a render which is a pixel-perfect match of the ordinary rendering method when it's completed.  I understand that there are tricks that can be used to reduce noise, but at the cost of extra processing time and usually small quality conflicts, like blurring.  My question essentially boils down to is this Cycles' current limit?
What is the difference between "gender" and "sex"? What is the difference between gender and sex?  says that gender is The mental analog of sex but that's too high English for me.  Basically, I'm developing a web-application that stores people's profile along with a field for gender/sex. Which name would be more appropriate?  __  [UPDATE]  After getting these good answers, I can figure out that,   Sex - Biological characteristics  Gender - Social characteristics   And, well, for my web-application, I went with the term sex, as it sounds more scientific and less political. P.S. Values for sex are clearly defined and can be easily validated (only two values * + an optional blank value).  * plus some anomalies. pgfpages and section I'm making a Beamer presentation. I need to show some notes on a second screen, so I'm using pgfpages.  Whereas, when I put a section, it appears 2 times :/ Here, it's a minimal code with the problem. Have you any idea ?  \documentclass{beamer} \usepackage[latin1]{inputenc} \usepackage[T1]{fontenc} \usepackage[francais]{babel}  \usepackage{pgfpages} \setbeameroption{show notes on second screen=right}    \begin{document} \begin{frame} \tableofcontents \end{frame}  \begin{frame} \section{test} toto \end{frame}  \end{document}   Thanks ! I saw a thing called VPN connections under the Internet button at the top of my screen.   So I would like more info on this, and possibly instructions on how to set one up. Thanks! Weird future tense usage I am now reading  book and have noticed a couple of cases of weird (for non-native speaker) future tense usages.   The point of the kata is to train your fingers and your brain. I'll do a kata or two every day, often as part of settling to work. I might do it in Java, or in Ruby, or in Clojure, or in some other language for which I want to maintain my skills.`   The phrase about doing a kata or two every day looks perfect for Present Simple. Why does the authoer use Future Simple instead?   However, a professional also knows that there will be times when he will fail, his risk calculations will be wrong, his abilities will fall short; he'll look in the mirror and see an arrogant fool smiling back at him.   Shouldn't we use Present Simple after when/if in this kind of cases? I am especially curious about this case as sometimes I forget to switch to Present Simple after if/when and I thought it is a critical error (which I didn't expect to see in a book). Install Biber in MiKTeX on a 64-bit version of Windows Update: As of summer 2015 Biber is also included in the 64-bit repositories for MikTeX. There is no need to install Biber manually any more, it can simply be installed via the Package Manager just like other packages.   The question  describes how to use Biber with MiKTeX. But on the 64-bit version of MiKTeX Biber isn't installed.  How it is possible to install Biber on a 64-bit version of Windows?  Can I use this ? Changing isometric drawing's constraint angles in Illustrator Eisenstein Criterion with a twist As opposed to the generic polynomial form for utilizing the Eisenstein Criterion ($a_nx^n+a_{n-1}x^{n-1}+\dots+a_0\in\mathbb{Z}[x]$ is irreducible in $\mathbb{Q}$) how do we prove that if $p$ is a prime, $x^{p-1}+x^{p-2}+\dots+x+1$ is irreducible over $\mathbb{Q}$? Considering the following formulae:  (i) $1+2+3+..+n = n(n+1)/2$  (ii) $1\cdot2+2\cdot3+3\cdot4+...+n(n+1) = n(n+1)(n+2)/3$  (iii) $1\cdot2\cdot3+2\cdot3\cdot4+...+n(n+1)(n+2) = n(n+1)(n+2)(n+3)/4$  Find and prove a 'closed formula' for the sum  $1\cdot2\cdot3\cdot...\cdot k + 2\cdot3\cdot4\cdot...\cdot(k+1) + ... + n(n+1)(n+2)\cdot...\cdot (k+n-1)$  generalizing the formulae above.  I have attempted to 'put' the first 3 formulae together but I am getting nowhere and wondered where to even start to finding a closed formula. Duplicate user in reputation league So I understand that this has happened in the past: , but all of the &quot;duplicate&quot; posts are marked as  so here is a new bug report: On the , I am listed twice:  While that's fun and all, it isn't exactly right. Consider $X = (a+b)^n-a^n-b^n$  where  $a$ and $b$ and $a+b$ are not divisible by $n$, $n&gt;=3$ is positive and prime, $a \ne b$ and both are greater than 1.  By the binomial expansion we know $X$ is divisible by $n$, but how can we study whether $X$ is divisible by $n^2$ or other powers of $n$? Specifically I am interested to prove $X$ is NOT divisible by $n^2$, but I am not sure how to prove or disprove it. Can I replace my road bike's front wheel quick release with any quick release? I lost my road bike's quick release. Pictured are what I lost. Do I need to find a specific quick release that fits, or does one size fit all/most? How do I open a terminal? Possible Duplicate:             I just got ubuntu running on my computer and now I am ready to write a program...but I can't figure out how to open a command terminal. I guess I don't know where to find which version I am running either. Any help would be appreciated. Thank you. What Did Lyanna Stark Say to Ned Stark? In the final episode of season 6 we see that Lyanna Stark is whispering something to Ned. What is she saying? Confirming that my own question is a duplicate by voting to close should have immediate effect Someone voted to close my question as a duplicate. I agreed, so I cast my close vote (I have enough reputation to vote to close).  . So I expected this to happen.  But it didn't. This confused me — is this not a question I asked after all? No, it is. Maybe I need to reload the page? Nope, the question still isn't closed. Is the asker confirmation feature broken? Well, there's the “This question may already have an answer here” banner at the top. What if I click “That solved my problem!”? Ah, that does close the question.  It turns out that only clicking “That solved my problem!” instantly closes the question. Casting a close vote has a different effect, it's just an ordinary close vote.  Please make casting a close vote equivalent to clicking “That solved my problem!”. Inconsistency in display of animated avatars It has been discussed previously that animated avatars are disliked because they cause a distraction from the content. However, currently animated avatars are not treated consistently.   On desktop, animated avatars are displayed as a still image, both in posts and on the profile page. On mobile, animated avatars are displayed as a still image in posts, but animated on the profile page.   I'm tagging this  because I'm guessing one of these two is unintended. Either avatars should animate on the profile page on both desktop and mobile, or on neither. (I sincerely hope that we are all agreed there should be no animation of avatars in posts.)  Example animated profile    This appears to animate on mobile, and show a still image on desktop (for myself and for other users who have tried).    I'd also like to hear arguments for and against animating only on the profile page, but the main purpose of this post is to clear up the inconsistency. Here is my problem: I've got a dialog with some parameters that the user can change (via a spinner for example). Each time one of these parameters is changed, I launch a thread to update a 3D view according to the new parameter value.  If the user changes another value (or the same value again by clicking many times on the spinner arrow) while the first thread is working, I would like to abort the first thread (and the update of the 3D view) and launch a new one with the latest parameter value.  How can I do something like that?  PS: There is no loop in the run() method of my thread, so checking for a flag is not an option: the thread updating the 3D view basically only calls a single method that is very long to execute. I can't add any flag in this method asking to abort either as I do not have access to its code. Trouble understanding Landau & Lifshitz writing about Lagrangians and Galilean Relativity We have two inertial coordinate systems, $K'$ and $K$. $K$ is moving with infinitesimal velocity ${\epsilon}$ relative to $K'$. Using Galilean relativity we can transform this into $v'=v+{\epsilon}$. Here Lagrangian is only a function of speed $L=L(|v|^2)$. $L'$ may differ from $L$ only by a total derivative of function of coordinates and time, i.e. $L'=L+\frac{d}{dt}f(q,t)$  $"$We have $L'=L(|v|^2+2{v}·{\epsilon}+{\epsilon}^2)$. [1. ] Expanding this expression in powers of ${\epsilon}$ and neglecting terms above the first order, we obtain $L(|v'|^2)=L(|v|^2)+\frac{\partial{L}}{\partial{|v|^2}}2v·{\epsilon}$ [2.] The second term on the right of this equation is a total time derivative only if it is a linear function of the velocity $v$ $"$  I understand nothing in the quoted part. How do we get [2.]? Why does $\frac{\partial{L}}{\partial{|v|^2}}2v·{\epsilon}$ being a linear function of velocity imply that it's a total time derivative? How do question bookmarks work? What does bookmarking a question mean? How do you bookmark a question? Do users get updates on their bookmarked questions? Are my bookmarks publicly visible? How do you see your own bookmarks? How do you see other users' bookmarks? How do you see which users have bookmarked a particular question? What impact does the bookmark system have on the voting system? Can I &quot;un-bookmark&quot; a question? Can I search within my bookmarks? What are the browser and resolution stats for SO users? Google Analytics (and some log parsers) will give you breakdowns on usage of different browsers, different versions of those browsers and screen resolutions.  I'm just curious to know what SO users user. Any chance we could get some stats on that? You may view this as commercial information, in which case I understand (as i'ts relevant to marketing/advertising).  I'm also curious to know the # of users who read and/or post from mobile devices and if so which ones.  UPDATE: Please refrain from personal anecdotes ("I use..."). I'm interested in actual usage, not personal stories. Thankyou. If $X$ is distributed $N(\mu_X, \sigma^2_X)$, $Y$ is distributed $N(\mu_Y, \sigma^2_Y)$ and $Z = X + Y$, I know that $Z$ is distributed $N(\mu_X + \mu_Y, \sigma^2_X + \sigma^2_Y)$ if X and Y are independent.  But what would happen if X and Y were not independent, i.e. $(X, Y) \approx N\big( (\begin{smallmatrix} \mu_X\\\mu_Y \end{smallmatrix}) , (\begin{smallmatrix} \sigma^2_X &amp;&amp; \sigma_{X,Y}\\ \sigma_{X,Y} &amp;&amp; \sigma^2_Y \end{smallmatrix}) \big) $  Would this affect how the sum $Z$ is distributed?