from Wikipedia (depth of field).  According to the depth of field (DOF) fomula, the DOF is linearly proportional to the circle of confusion (C), in which C is also linearly proportional to the pixel size. Thus DOF is linearly proportional to the pixel size.  If that assumption is correct, then does that means some of the DSLR with APS-C sensor size and low pixel number would have a shallower DOF than some of the full frame DSLR with a high pixel number, assuming using full frame equivalent lens by considering the crop factor and same distance to the capturing subject?  Now calculating the ratio between DOF of Full frame (FF) and that of crop body (C), also applying the crop factor to the focal length and F number, we get:   Thus, C would have a shallower DOF than that of a FF when using FF equivalent lens, when:   For example the Pentax K-100D has 6 Mega pixels with an aps-C sized sensor, comparing to Pentax K-1 with a full frame sensor and 36 Mega pixels.  As such,   The DOF of K-1 would be about 4 times deeper than that of K-100D.  Please correct me if I my logic is not sound. Thank you for your time and effort!
I have been reading about depth-of-field and presume to have a sufficient understanding of what it means and how it is related to lens properties, lens aperture, focal length, sensor format size and probably even print dimensions in case the picture is being printed. I do have a question about how/if depth-of-field depends on the dimension of a pixel. Let me elaborate:  Given two sensors with differing pixel sizes: x and 4x, the latter sensor integrates more light per-pixel than the former, however, it might have a lower resolution if the sensor dimensions remain fixed. Theory suggests that the depth of field is determined by those circles-of-confusion which are very close to being an in-focus point, and this perhaps also means that these very small CoCs fall within the integration area of the same pixel. Now when a CoC becomes larger than a pixel (like also in the case of diffraction blur), there is some spreading of intensities among neighboring pixels and this would clearly lead to blur. However, if one was using the 4X sized pixel, even with a slightly larger CoC, the intensity would still integrate into the same pixel area, and would thus perhaps be in-focus? Is this the right assumption? And if so, is there any analysis of pixel-area dependence of depth-of-field? Moreover, depth-of-field is in some sense independent of the integration medium as it clearly occurs in analog film devices as well, so is there a trade-off or a difference in depth-of-field between film and digital cameras?  Please point me to the correct references for this question. Please correct me if there seems to be a fundamental issue with the assumptions made above.
Local server updates for the network I have setup one computer on our network as the file server. Because Internet here in Tanzania is both slow and expensive I would like that one system to download all the updates and then the other 10 computers on the network to get those update files from the server. I'm a bit of a noobie to Ubuntu, but really want to learn how to get this working smoothly so as to help other NGOs and schools here in Tanzania. Brendon Solving $x^3-y^3=xy+61$ in integers I'm trying to solve the following equation:  $$x^3-y^3=xy+61$$  I got:  $$(x-y)(x^2+xy+y^2)=xy+61$$  But I can't go any further. I am looking for a solution in integers.  I need some hints to proceed, please! When does Bleeding Attack effect apply? I've designed for a campaign a duo of rogues. My character is as , and his follower is a Knife Mistress. Couple of question about them. Our party is about to ambush several . My Sniper will hide near their camp, and shoot the weakest one when fight begins. His follower will then rush the troll and slice him in several pieces. My Sniper has the Bleeding attack feat:  Bleeding Attack (Ex) Benefit: A rogue with this ability can cause living opponents to  by hitting them with a sneak attack. This attack causes the target to take 1 additional point of damage each round for each die of the rogue's sneak attack (e.g., 4d6 equals 4 points of bleed). Bleeding creatures take that amount of damage every round at the start of each of their turns. The bleeding can be stopped by a DC 15 Heal check or the application of any effect that heals hit point damage.  Emphasis mine. Thus, a normal enemy would bleed every turn, until he get cleaned of the bleeding effect. However, troll have a special ability, which is  5 (acid/fire)  Regeneration (Ex) A creature with this ability is difficult to kill. Creatures with regeneration heal damage at a fixed rate, as with , but they cannot die as long as their regeneration is still functioning (although creatures with regeneration still fall unconscious when their hit points are below 0). Certain attack forms, typically fire and acid, cause a creature’s regeneration to stop functioning on the round following the attack. During this round, the creature does not heal any damage and can die normally. The creature's descriptive text describes the types of damage that cause the regeneration to cease functioning.  So, the troll will automatically get rid of the bleeding effect during his first turn. My question is: Does the bleeding effect apply before the regeneration, or get neglected, because the troll will heal during his turn? Am I right to assume that, Bleeding attack effect getting triggered at the beginning of the troll turn, it will deal him the damages before the wounds heals? Hi is it possible to exclude traffic from a certain country in google analytics?  If yes, how do I do it? About the semantically related words Google's algorithm uses in mixed language websites Because I'm Latin, sometimes I use a word in English while talking in Spanish.   In a website, for example, I could be interested in ranking for a word as “promoter” inside a page in Spanish, because that is how my public understands that concept.  Does the latent semantic indexing (LSI) (or whatever Google uses for semantic relation) fail to relate “promoter” with the content (because there are not related words in English) and then could that prevent my site from ranking? Where can I send feature requests? Is it possible to change your spawn point? Why "grand theft auto", not "grand auto theft"? There is a video game series called "Grand Theft Auto".  According to its :     The name of the series references the term used in the US for motor   vehicle theft.      [...]      Motor vehicle theft or, grand theft auto, is the criminal act of   stealing or attempting to steal a car (or any other motor vehicle).   I always wondered why this term sounds so strange.   Shouldn't it be "grand auto theft" or maybe "grand theft of auto" instead? Are there any other terms with strange words order and/or missing prepositions like this? How do you get \mathbb{1} to work (characteristic function of a set)? Normally while searching using grep, the command I was using was this:  grep -nri "String"   whereas most of my colleagues do this:  grep -nri "String" *   What does the latter do (the * part)? Text not very readable on different image backgrounds I've come here seeking for a bit of design help or advice on how I could possibly improve the following:  Like the title says, I'm having a website banner with multiple text displayed on different images as backgrounds. Now, since most of the images are dark, I've set the font color as white. But even then, some of the text is not very readable on a couple of images like:    Since I'm working with CSS, I've tried different options such as:  Adding Text Shadows:    CSS:  text-shadow: 3px 3px 0px #000;  Also tried, creating a semi-transparent box around the text:      I feel the box one looks out of place.  I've created a  for anyone who knows CSS. If not, please feel free to advice me based on your imagination alone.  PS: You could also advice on using a different font if that would help it stand out better. Why is defragmentation unnecessary? Why is defragmenting unnecessary in Ubuntu? Are the suggested edit audits too easy? Yes, this might be another post complaining about audits. But, in this case, I want the audits to be more difficult.  Specifically, I'm concerned that the suggested edits audits are just too darn easy to spot. They don't behave anything like actual edits, and so after a tiny bit of experience (and electric shocks from audit failures) I think they wouldn't slow down a roboreviewer at all.  Unlike the other queues, which use real data (and are legitimately, in my opinion, difficult), the suggested edits audits look like this:    In about 500ms I can tell that is a bogus edit (less time than it takes for the buttons to unfreeze). After just a few of these, I'm about 99% confident I could tell you which edits were audit edits and which ones were not, and I don't think I actually have to spend extra time on them. On the other queues, picking out the audits is very hard because they use real data, and so I wouldn't bother to do so.  Were I a roboreviewer, I could get on with my Accept-happy life, only pausing to reconsider when someone actually changes the text. (Seriously -- how many real edits have you see which change the text in such a drastic manner? 95% of edits are grammar, spelling, formatting or some combination of those).  Are the suggested edits audits too easy? Is the "Markov-chain random-edit-word-salad" too easily detectable? Or does it legitimately slow down and/or deter robo-reviewers? Should we (and can we) be using real data for the suggested audits queue too? Why do Lambertian Reflectors Privilege the Observer? Questions link almost unreadable when active on meta If you click on  the font color is almost unreadable on the main site here.  Is it possible to make it a slightly different color? (I cannot say if darker or lighter is better) In almost every canon (that is, visual) source, Force users typically wave a hand to invoke the Force to move or manipulate objects, people and thoughts. I get out-of-universe this is a visual cue that the Force is being used, but in-universe is it strictly necessary?  (The only exception I can think of is when Luke is training on Dagobah and is balancing rocks while standing on one hand with Yoda on his foot. He doesn't appear to be waving his hand to move the rocks.)  Is this addressed anywhere in-universe, even in Legends? How does apt-get really work? Okay, I understand how I may use apt-get {install|upgrade|remove} mypackages to install, upgrade, or remove binaries as well as their configuration data files and dependencies (actually, remove will only remove the binaries unless additional flags are provided).  I am not looking for how it is used as the man describes this, but high level what it is doing.  My end goal is to create a means for me to install and manage some custom software (created by a make file) on multiple remote machines, and I need to learn more about the process.  If answers to this question are based on which distribution is used, please tailor to Debian.  In addition to generally how it works, I have the following specific questions:   How does the client that is accessing the apt repository keep track of the files? Must the repository be hosted on the same operating system (i.e. can apt repository be hosted on redhat)? How are the locations to install files specified?  Is this specified by the .deb file? How is a remote machine accessing the repository?  Is it just ftp(s) or http(s)? Is the machine that is hosting the repository running special software (like gitlab for a git repository), or is it just some structured file system? jquery selector not working with [ ] Android Studio shortcuts are not working I use Android Studio in Ubuntu and everything was working fine. Since two weeks that shortcuts stopped working, Ctrl+C, Ctrl+V, Ctrl+Z. I tried to change Keymap in Settings but without success.  What could be the possible problem? How to search the internet for terms with special characters As I learnt from this , Google has no ability to search for special characters. Let's say I want to search for ss!. Are there any other search engines that can achieve this? Please do not propose any programming code search engines since this is a general search.