Wikipedia:Reference desk/Archives/Miscellaneous/2017 February 20

= February 20 =

Exif data - subject distance
The Exif data on this photo says that the subject distance was 19.95 meters. I figured that it gets this from where it focuses. But looking at this satellite view, I was actually about 120 meters away. Why is it off by a factor of 10? Bubba73 You talkin' to me? 03:49, 20 February 2017 (UTC)


 * The 19.95 meters is more believable. Why take a pic of a house from 120 m away ?  BTW, that's a factor of 6, not 10.  StuRat (talk) 03:57, 20 February 2017 (UTC)


 * Whoops, it is a factor of 6 instead of 10. But I know where I was when I took the picture yesterday.  I was 120 meters away.  I was that far away because I didn't want to go on private property, as you can see in the satellite view.  You can also check that the focal length of the lens was 130mm on a crop sensor camera, so you can calculate the approximate distance from the field of view.  Bubba73 You talkin' to me? 04:54, 20 February 2017 (UTC)


 * Maybe it doesn't calculate that from the focus ? Or it may just be a bug. StuRat (talk) 05:07, 20 February 2017 (UTC)


 * My suspicion is that it is telling you the distance you would have been at to see the house as it is in the photo without zoom - it is telling you that 120m with your zoom is equal to 20m without zoom. Wymspen (talk) 09:25, 20 February 2017 (UTC)


 * A quick calculation shows that is at least close to being right. I can experiment and check it.  Bubba73 You talkin' to me? 16:15, 20 February 2017 (UTC)


 * (Edit conflict) Nikon cameras are notorious for calculating focus distance wrongly, which causes big problems with using third-party flashes. I tried using the Scantips subject distance calculator, and it estimates that you were 118 metres away from the house. That sounds about right. Smurrayinchester 09:38, 20 February 2017 (UTC)


 * I looked at some other photos taken the same day and I think they are all wrong. I first looked at the one at the top because I was wondering how far I was away.  When I saw the 20 meters I checked with the map since I knew that was wrong.  I looked at some I took from across a street and it said about 10 meters.  It had to be at least twice that.  Then some others said 2 meters and I think those were about twice as far.  And one had no data.  Bubba73 You talkin' to me? 16:01, 20 February 2017 (UTC)

Academic etiquette - letters of recommendation
I'm increasingly being asked to write reference letters for students. In this context, I am often asked to include information on how I got to know the student - which is typically before they earned their current degree. Do I use their current title and (and particular honorific) when talking about the person before he or she earned the corresponding degree? E.g. "I first met Dr. Miller when he was an undergraduate student in my algorithms class"? Or is it "Mr. Miller" in that context? I used to work around this by using first names ("I first met Max when he was an undergraduate student..."), but at least one institution suggests to avoid first names altogether. Thanks for any help! --Stephan Schulz (talk) 10:01, 20 February 2017 (UTC)


 * The former. You're talking about when you met the person he is today, not the person he was then. --Viennese Waltz 10:36, 20 February 2017 (UTC)


 * I believe academic titles are retroactive, so you can safely address them as "Dr." La   Al qu im  is ta  15:28, 20 February 2017 (UTC)


 * "Dr. Smith weighed 6 lbs, 9 ounces at birth ? Was that with or without his baby stethoscope ? " Perhaps "The future" should be prepended to such a statement. StuRat (talk) 16:05, 20 February 2017 (UTC)


 * I had considered that, but it reads very stilted, and also does not, IMHO, seem to meet the tone for a personal letter of recommendation. --Stephan Schulz (talk) 16:17, 20 February 2017 (UTC)
 * This crops up in the law reports, where judges refer to previously decided cases.  The formula is


 * I've written and read a few rec. letters in the sciences. I've on occasion just used last names when I thought it smoothed phrasing. E.g. "Schulz is a fine researcher, though he does sometimes get a bit too focused on small-scale wording changes to his manuscripts".  When you say "I first met Dr. Schulz when he was an undergraduate...", that means you're talking about a guy called Dr. Shulz now. Even "Dr. Shulz weighed X at birth" is completely fine. There's a guy we call Dr. Shulz, and he weighed X when he was born -- no problem whatsoever.
 * You can of course attempt to clarify via "I met the future Dr. Schulz when he was..." but IMO that sounds very awkward, and if anything would indicate you had been using some sort of time travel. "I met the man who is now known as Dr. Shulz..." avoids that particular problem, but sounds even worse. Recall that readers of rec letters value concise and clear writing - not unnecessary gymnastics that use up a lot of words to clarify something that nobody was confused about in the first place.
 * Just call them Dr. if they've earned the title, or Shulz if that seems better in specific sentence. That's the advice I've received and followed, your mileage may vary. SemanticMantis (talk) 17:09, 20 February 2017 (UTC)
 * (Also searching "[title] was born" is a great way to find tons of examples of this usage, from blogs to books to newspapers. Almost nobody was a priest or doctor or king or president when they were born, but that's ok. E.g. here's a selection of scholarly articles that use "president was born" .) SemanticMantis (talk) 17:16, 20 February 2017 (UTC)
 * Thanks (all), that's really helpful. --Stephan Schulz (talk) 17:33, 20 February 2017 (UTC)
 * And there is nothing wrong with attention to detail in writing! If you expect people to read it, put in the effort. If not, there is no point in writing it in the first place! --Stephan Schulz (talk) 17:35, 20 February 2017 (UTC)
 * Of course not! Sorry, didn't mean to insult you, just having a little light-hearted fun with my example sentence:) SemanticMantis (talk) 17:52, 20 February 2017 (UTC)
 * Me too, as I hope is clear ;-). --Stephan Schulz (talk) 17:58, 20 February 2017 (UTC)
 * As Posthumous birth, it is actually possible to be born a king (or queen regnant for that matter), albeit very rare. Nil Einne (talk) 10:07, 21 February 2017 (UTC)

Re "at least one institution suggests to avoid first names altogether", how preposterously arrogant. It's your reference. If they don't like the way you write, they can edit it themselves. The use or non use of someone's first name by the referee bears no relevance to someone's suitability for a position. --Dweller (talk) Become old fashioned! 11:22, 21 February 2017 (UTC)
 * The suggestion was made in the context of writing gender-neutral letters of recommendation. I don't know if the mere fact that the first name usually encodes the gender is the problem, or if the institution has seen a pattern of "Dr. Miller" for men vs. "Veronika" for women. Or, always a possibility, that some admindrones were task with writing recommendations, and just wrote something without deeper thoughts. --Stephan Schulz (talk) 12:41, 21 February 2017 (UTC)

Article on slavery
Why is there no mention of Democratic lead segregation in the South and the KKK in the article on slavery?Petitechatterousse (talk) 18:45, 20 February 2017 (UTC)petitechatterousse


 * The usual answer to questions of the form "Why is X not mentioned in article Y", is "Because nobody has added it. If you have reliable published sources for the information, you are welcome to add it to the article; or if you are not confident in doing that, or if it is likely to be controversial, please start a discussion on the article's talk page". --ColinFine (talk) 19:00, 20 February 2017 (UTC)


 * Which article do you seek more information about? The Wikipedia article titled Slavery is a very general overview and does not deal with Slavery in the United States extensively.  The article Slavery in the United States specifically mentions the Democratic Party's position on slavery in the section on the 1850s.  The Ku Klux Klan did not exist until after abolition.  -- Jayron 32 19:05, 20 February 2017 (UTC)


 * See Solid South for the era when segregationist white Democrats controlled the Southern US. StuRat (talk) 20:05, 20 February 2017 (UTC)

Luggage bag
What kind of luggage bag is currently used by many (human beings) that could take weight of up to 23 Kg or more for migration purposes from country to country? 103.67.158.199 (talk) 18:59, 20 February 2017 (UTC)


 * Wikipedia's article on this subject is at Baggage. You can peruse that article to find information about many types of luggage.  You can even follow links to more articles about individual kinds of luggage, and come to your own conclusions about a bag appropriate for your needs.  -- Jayron 32 19:13, 20 February 2017 (UTC)


 * A trunk (luggage) ? Note that if you will have to carry it yourself over a distance, you will need wheels.  See luggage cart and wheeled luggage.  You will want to avoid any soft-sided containers for such weight.  StuRat (talk) 20:02, 20 February 2017 (UTC)


 * Military backpacks/rucksacks can take up to twice that weight - and soldiers going into combat may well carry such a load. Wymspen (talk) 20:55, 20 February 2017 (UTC)


 * The problem with using soft-sided luggage with that kind of weight is that if anything with a hard edge, like a jewelry box, finds it's way to the bottom, that could cause a tear. Also, the risk of theft is higher if anyone with a knife can cut into the bag. StuRat (talk) 21:57, 20 February 2017 (UTC)


 * Jesus. Tough luggage like "hardside" or "hard shell" is available from many manufacturers, such as Samsonite.  Otherwise just pack a normal bag, like 99% of the rest of the world.  I regularly travel with normal, non-hard luggage across the globe without fear of a "jewellery box" destroying it from within, or rogue thieves slicing my bag open to steal my underwear.  The Rambling Man (talk) 22:09, 20 February 2017 (UTC)


 * 23 kg is more than the usual amount of weight for one bag, and that weight implies more than just underwear. I use soft-sided carry-ons, but I can keep an eye on them, and the flexibility makes it easier to jam them into tight compartments.  But for that kind of weight, in checked baggage, nope.  StuRat (talk) 22:30, 20 February 2017 (UTC)


 * Nonsense. Common airlines such as British Airways allow 23kg in each carry-on bag.  Please, get some facts and stop using anecdotes.  The Rambling Man (talk)


 * I didn't claim they won't allow it. I said it's a bad idea. StuRat (talk) 22:57, 20 February 2017 (UTC)


 * This site lists the fees for baggage. Most or all of them have a 50 pound limit on checked baggage. (Translated to approximately 23 KG.) This appears to be checked baggage. Presumably your carryon could be heavier, unless they are now weighing carryons as well. ←Baseball Bugs What's up, Doc? carrots→ 23:40, 20 February 2017 (UTC)


 * It would have to be something rather dense to get the that weight in the size of a carry-on bag, and imagine a person trying to lift such a bag into an overhead compartment, especially your average woman (God help the person sitting there if the bag falls on their head). StuRat (talk) 00:06, 21 February 2017 (UTC)
 * It's to be hoped that someone carrying a more-than-50-pounds bag would already have tested hefting it to eye level. What I'm unclear on is whether they test the weight of carryons. It's been a while since I've flown, and the rules keep changing. ←Baseball Bugs What's up, Doc? carrots→ 01:29, 21 February 2017 (UTC)
 * Most airlines theoretically restrict carry-ons to 7 or 8 kg, and also to rather small dimensions. They have tape measures and scales (and more and more often size boxes that your luggage is supposed to fit). However, checking luggage is expensive and takes time (for the airline), so in practice you can get away with basically any weight or remotely plausible size. It's a win-win-lose situation, and the loser is the guy who has to share your overhead compartment, so nobody with influence. The one time I flew business class from Jakarta to Frankfurt I took my main suitcase (plus my normal carry-on back-pack) as cabin luggage - 20 kg, complete with shower gel, tooth paste, deodorant, nail scissors, and other assorted toiletries, with no problem. I may have been lucky, but experienced business travellers tell me this is reasonably normal. --Stephan Schulz (talk) 15:02, 21 February 2017 (UTC)
 * They usually have scales and measuring devices in the terminals, but they don't seem to be used often. I've flown a moderate amount, but only once have I had my carry-on weighed. ApLundell (talk) 18:01, 21 February 2017 (UTC)
 * What I've seen most often is a box that your carryon is expected to be no larger than. ←Baseball Bugs What's up, Doc? carrots→ 18:37, 21 February 2017 (UTC)
 * So, going back to the OP's question (What kind of luggage bag is currently used by many (human beings) that could take weight of up to 23 Kg or more for migration purposes from country to country?) most luggage bags will take 23kg. The rest of this discussion is navel-gazing and just about people who think they might have travelled a bit telling other people who probably haven't travelled at all about luggage.  That's not the purpose of the Ref Desk.  The Rambling Man (talk) 20:01, 21 February 2017 (UTC)
 * What's your specific reference for "most luggage bags will take 23kg"? ←Baseball Bugs What's up, Doc? carrots→ 14:24, 22 February 2017 (UTC)


 * This depends on how you intend to travel, but from the sounds of it, this for a flight, right? I have been in this exact situation, and just used a Tripp Superlite case, which will take 23 kilograms (say, a week of work and home clothes, essential homeware, toiletries and a few books) no problem, plus a backpack for electronics and valuables that I didn't want to check in. Vacuum bags (also called space bags or compression bags) will help you compress the clothes and fit more in. Although it's a soft case, has a hard protective lining so it can't be cut through easily, and it has the advantage of being expandable to fit awkwardly shaped objects. In my case, moving from country to country meant a flight and two train journeys - if you can do the journey by car, I'd recommend cardboard moving boxes, while if this migration is on foot you'd want a backpack or at least a heavy-duty waterproof large-wheeled case (if you are certain of always following a paved road). And of course if you can, bring only what you need immediately and can't find in your destination country - the heavy stuff can be sent by surface mail. Smurrayinchester
 * Good answer to the OP's original question. The Rambling Man (talk) 20:01, 21 February 2017 (UTC)