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CharonY

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Everything posted by CharonY

  1. With film it is a different process and I would agree, color filters would be quite helpful. Also on film you do not have the issue that layers on top of sensors filter out certain wavelengths (though one probably can also optimize by selecting the right film). For post pretty much everything would go that would let you color grade your image. I do not have photoshop, but in many freewares (including gimp) you can e.g. adjust white balance (or otherwise essentially change the LUT). These things have pretty much made (for the most part) color filters obsolete in digital photography as you can either directly tell the camera or later in post what measured RGB value corresponds to what color. For example, using a blue filter gives you a particular cast that you can emulate by shifting the whole color table towards blue. Using an actual filter could (depending on the properties of the glass and coating) limit the light hitting your sensor. The best and cleanest images I have seen (aside from specialized CCDs) were from cameras with removed IR filters (or they may have exchanged from bandpass filters allowing H-alpha to go through, forgot to ask). But again, this is not really my area of interest and expertise.
  2. Possibly. I think MP had a better knack at being absurd and surprising. For that alone I found it funnier than the more slapstick-oriented humour. Also I found the satirical note in movies such as the Life of Brian having just the bit more bite to it.
  3. Does OP mean specifically colony collapse disorder or the overall count of managed colonies? If you want the big picture, quite a number of things have to be factored. The overall number of agriculturally used hives have increased, but there are at least two major issues. The first is that for some reasons the number of bees surviving winters has declined and on top the mentioned colony collapse disorder has further decreased their numbers. The economic damage is not there yet, as beekeepers have been replacing the bees. However, the question is still where the trend is going, what are the causes, and what can be done. There is no final consensus yet (to my knowledge) and most wide-scale approaches are epidemiological in nature. As vague as it is the USDA/EPA statement above is probably a good summary, considering the unknowns.
  4. Well, when it comes to astro shoots the people I know (incidentally almost all being physicists, though not all of them astrophysicists...) either use a DSLR without filters or CCDs with filters. When it comes to DSLRs they already have filters built-in that may filter out wavelengths that you actually want to capture from the stars.. Some have therefore their IR filters removed (or exchanged to an IR filter with transparency to H-alpha). That greatly improves image quality as you get more signal. The only filter they may use in addition tend to be broadband filters to minimize light pollution. That, in turn allows you to increase exposure time (assuming you have a tracking mount) without overexposing it rapidly (i.e. increase signal to noise ratio). However, if you are using film instead of a digital sensor, use of filters may be more important. I am not doing astrophotography myself, but I would imagine (and am being told) that the singal to noise ratio is the crucial bit as the rest can be changed quite easily in post.
  5. CharonY

    "Trolling"

    Indeed. I would like to see him thrown into a meeting with some leading female scientists and watch his evisceration by these overly nice people... Nice example of trolling, though.
  6. From an analytical chemistry perspective a master's degree can give you more technical positions in Industry (such as analyst or technician). Getting a research in academia beyond a simple postdoc (which is supposed to be a transitional period) is tough and considering the almost worldwide funding cuts is not going to get easier in the next years. Networking is indeed more important than ever, but I would not recommend anyone trying the academic route right now if one is not heavily supported. Just to give some anecdotal numbers for academic job searches from colleagues in various US universities (tenure-track assistant prof level, medium sized public unis). On average the number of applicants was 100-200 a few years ago (before the market crash). By now they get more in the area of 300-400. This i partially because many unis had or still have hiring freezes that left people out in the cold. I am not too familiar with the situation in the UK but I vaguely recall an article by the Royal Society that described an equally bleak outlook.
  7. Intuition does not give you time to distance yourself from the decision-making process. That is basically the definition of it. Once you start picking apart the facts, you do not use intuition anymore.
  8. Nope, just blind stupid association without providing evidence of conclusion. For the reasoning step you have to slow down and take apart the bits. Intuition would say take the left car, without you knowing why. You could inductively conclude that the left car is faster because it looks like a sports car and that is what you want. Truth could be that you just like the color of the car.
  9. Intuition is not based on reasoning but very prominently on pattern recognition. It is much faster than deductive or inductive reasoning. Typical examples are, say, a mechanic that realizes that a passing car is defective before he/she realizes that it is because the motor has a weird rhythm. Or a chessmaster that knows at a glance who is going to lose, though it takes more time to reconstruct why it is the case. In these examples the persons are experts on their fields and have accumulated sufficient knowledge that they can match new situations with patterns that they experienced and associated with certain outcome (e.g. defective motor). In these situations intuition can be very powerful to make accurate and, more importantly, quick responses. However, once we step outside our zone of knowledge, intuition still kicks in but the decisions can be quite irrational, without you realizing. For example, if you have to choose between cars and have no idea what their specs mean, you may choose the blue one, just because blue happens to be your favorite color. We are also great in post-hoc rationalizing and making things up. In the same example you may at some point learn that the specs of the chosen blue car are actually effectively inferior to the other one. But then you rationalize it by claiming that the intangible factors (e.g. handling and so on) are much better and that your choice was solid and rational. All the while not realizing that your initial impulse was just to get the blue one. Statistical choices are another example in which intuition usually fails. For example, rationally one should take bets once you get a better than 50% chances, as in the end you are likely to come out on top. However, humans dislike taking losses and hence the average bet people take is much higher, which is also irrational. Daniel Kahneman has published quite a bit on decision making and the follies of intuition. At least in situation outside your expertise. And then there are things like selective memory which make you think that you made great (intuitive) choices (by forgetting the times where you screwed up) so that you try to apply intuition in situations where it really does not lead to good choices...
  10. The last DSLR I had was the Nikon 7000. It is a capable camera but the issue I had was flexibility. In social situations I do not want to be "that guy" with the huge camera. If I need to take a flight the lens bag was quite significant in size and during hikes I found it a bit awkward. In the bag it was too slow to get out when I found an interesting animal. Using certain types of shoulder straps or fanny pack style packs made it easier, but especially with the necessary long lenses it was still a bit heavy, especially if you have to carry additional gear and water. At some point I looked at the MFT offerings from Olympus and Panasonic and fount the niche for me. If I want to have a small camera for a social event, I put a pancake lens on the Olympus PM2 and it just looks like a simple point and shoot (though the picture quality outshines entry-level Canons). What I dislike about that small camera is the lack of external controls. However, for that I got me another MFT body that has more controls (Panasonic) and quite frankly, I have been quite happy with the Olympus/Panasonic lens selection. What do I dislike? Mostly that these (older) cameras I have still are not ideal when it comes to continuous AF. I am looking at the Sony A6000, however, as the initial results look quite promising and the camera is not too expensive (though I will wait until the price comes down). Another thing that I dislike is that many of the high-end MFT lenses are quite expensive. But then the same could be said for Canikon. And that is about it. However, I have informed myself quite a bit before I took the jump so I had little to be disappointed about. I think the same is not the case if someone just bought (SLR/DSLR/Mirrorless/Full-frame/Aps-C/whatever) because someone said something like "take Canon, cause all pros use it". Obviously, the more you know what you want to do, the better your buying choice will be. Most people I know do not use color filters of any sort on their astro shoots.
  11. One point that I would like to make is that if you want to really spend money in photography, you should know that you do not spend the money on the body, but rather on the lenses. Things like sharpness are essentially lens dependent and some high-end non-changeable cameras have better image quality than DSLR counterparts since they are able to create a lens that is just perfect for the sensor being used. Camera bodies are a bit secondary except for certain conditions. For example a full or medium frame theoretically give you the widest options in terms of noise and so on. However they are heavy and require large and heavy lenses. If you want to take studio photos, it is not an issue at all. I would like to see you using a huge Hasselblad during a hike, though. The best camera is the one that you have with you. All modern cameras can do at least 1min exposures. For very long ones most cameras (except some very compact bodies) have access for remote shutters that let you set the length via bulb mode. Some compact bodies that do not have a port still allow control via wireless or infrared. With regards to multiple in-camera exposures, it depends on the camera a bit. Even modern DSLRs do not have it (especially entry-level, such as the Canon T3i) though others may (5D or Nikon D7000). Among the interchangeable mirrorless most of the recent crop have it. That being said, in most cases it is just a digital overlaying of imaging, not different than doing it in postproduction, as you mentioned). So the features are pretty easily fulfilled, but if your actual question is what specific camera I would recommend, well that depends. If you do astrophotography where you already have a lot of gear to carry around, getting a full-frame for better light collection probably would not hurt much in terms of weight. But then you also have the mirrorless Sony A7 full frames that may be of interest. That being said some cameras such as the Olympus E-m10 and e-m1 have a live update during bulb exposure. I.e. you can see how the image (star trails etc.) forms during exposure and stop at the best point. While they may require higher Iso and be noisier than with a larger sensor camera, in some situations it can be useful for creating specific images more easily. Photography has come to a point that even at modest expenses the quality tends not to be a too limiting factor for everyday photography. In fact, looking at many well composed images (even astrophotography) it is usually hard to distinguish with which camera it has been taken, once we hit a certain price point (which is not terribly high). I disagree completely. Just because it has mirror it is not necessarily the best camera for the job. Mirrorless are quite viable systems that certainly surpass entry-level DSLR quality and are used in commercial settings. And there are serious Leica photographers around that paid a lot of money for their system... Again there are certain tools for different situations and lens/camera combos are not different. Even with a single brand and same sensor size, there are marked differences between the lines, usually in terms of ergonomics (buttons) and certain features (e.g. AF speed). There is no perfect tool for all situations. However, in many cases the capabilities of the camera surpasses the abilities of the casual photographer.
  12. As generic gear an airblower (if you got interchangeable lenses) and a lenspen are great. Edit: part of my kit does include micro four third mirrorless cameras. One of the reason is that I got a bunch of old manual lenses including some from Nikon and Kironfrom the 60s-80s which are gorgeous. The nice thing with the mirrorless is that I could just add an adapter and use them with that. The EVF made metering and focusing much easier, too.
  13. Many cameras that are designated as point and shoots do have manual options. The main differences tend to be interchangeable lenses, number of controls (i.e. buttons), body size, sensor size. There now fewer pure automatic P&S as hardly anyone is buying them. Instead there are now high-end cameras with (usually, but not always) smaller sensors in a small body. The Ricoh GR and Sony RX series are good examples thereof, but they can easily cost above 400 or 500 USD. But even the cheaper ones often have ample controls (though with very small sensors aperture sometimes becomes slightly pointless in terms of DOF control) and raw output. The thing is that there are also cheap interchangeable lens cameras in the $200-400 segment that make purely automatic P&S quite useless. And for the cheaper segments usually cell phones (such as the iphone) have basically replaced them. In addition, mirrorless cameras with interchangeable lenses have caught up and in some cases surpassed DSLRs (though they would not be counted as point and shooters). The Sony A7 series is basically an interchangeable system in a relatively compact body but with a ~35mm size sensor. If it comes to starting shooting I tend to recommend gear based on what you want to do. If you want to stay casual and never upgrade and need something unobtrusive (e.g. for social events) something like the Ricoh is perfect. Great image quality, very small and has all the controls to take superb photos. Want to step up in dark areas? The Sony RX 1 is essentially a full frame camera in a compact body. If you wan to have interchangeable lenses and want to upgrade, there are again numerous things to try out. Do you love to shoot with liveview? Go mirroless (micro four third, Sony E mount, Fuji). Prefer optical viewfinders only? Canon/Pentax/Nikon. Want to have the option for lightweight gear (body and lenses)? Mirroless.. and so on. There is, in my mind not a perfect starting gear, but they are all different tools for different situations. You would buy canvas and brushes depending on what you want to paint, not because one is a beginner/advanced gear. I agree completely. Also take a look at Cartier-Bresson. The photos are often technically less then perfect. However the composition and the capturing of the moment... brilliant.
  14. I would not say that. There are quite sophisticated point and shoots (the lower end is getting eaten away by cell phones) which let you do most what a DSLR/mirrorless would let you do (except changing lenses). But then there are brilliant fixed lens cameras, too. Point is that that gear is often secondary to the skills of the photographer. I agree that understanding your camera and its functions would be an important step, there are too many who use a DSLR on scenery mode, in which case a point and shoot would often yield comparable results. PS I would love to toy around with a twin-reflex.
  15. I think modifiers and lighting are advanced elements of photography. While people may learn differently, my feelings are that overall composition and proper framing is a good first step as it establishes a baseline. From there it is easier to visualize what you would have changed (light from a different position, removing/adding shadows) and add tools for certain situations. It is easy to go overboard and shoot with three flashes tripod with gimbal head flash gels and various filters without actually improving the image. Start basic, and build up gear as you find the need is my advice (though admittedly, a tripod comes in handy quite early on).
  16. You are right, oxygen influx will severely alter the growth kinetics of your bacterium. Even if you could reach anoxic conditions faster, the influx of oxygen will either damage your cells (in case of obligates) or allow additional respiration (e.g. facultatives). An anaerobic chamber could work, and chances are that the CO2 will not make a lot of difference, unless CO2 fixation is expected. What I would recommend is to use an sealed bottle for cultivation (those with large rubber stoppers) and use an gas-tight syringe that is flushed with nitrogen to draw samples for measurement. That would minimize perturbation of your culture and give more reliable results.
  17. I will move that to the homework section, maybe someone can help you with it. I have the feeling that something is missing and I have no idea what is meant with "clock-like" in this context.
  18. I would add: "then pick out your favorites and figure out why you like them. For good technique it is important to distance yourself from the situation in which you took them so that the composition of the picture talks to you, instead of the situation (e.g. vacation) in which you took them."
  19. The rule of thirds is more a guideline for beginners to avoid basic composition errors. The image tends to be a bit less static and invites eye movement through the image, instead of pinning it in the middle. However, there are a lot of compositional situations where you want to break the rule, depending on what your point of interest is and what the total effect of the images is going to be. For example, high-symmetry images require breaking the rule (for obvious reasons). Or images that are to convey dynamics can be created by using lines that draw your eyes towards the point of interest, instead of it being positioned in one of intersecting lines. Likewise low depth of field images create depth in the third dimension, and can create dynamic in a different way. Remember, the rule is not about subject and not even merely about subject placement. Instead it is about the overall composition of the image (think in terms of lines and brightness throughout the image), the balance thereof and finally the desired effect. Interestingly, the framing that was described in OP could easily lead to a non-rule-of-third-image (i.e. people dead in center, but with lines surrounding them; probably works best with some diagonals). In the end, it is a crude tool, useful when you start off, but if you adhere to it for now other reason that it is a rule, you have to work on composition and creativity to improve photography skills.
  20. That is the ideal case, though rarely are tips that fine in reality. Also, depending on the type of surface (especially soft, irregular ones, like biological specimen), the tip can easily get into contact with the surface (e.g. due to inevitable delays of the feedback loop and piezo). Also in contact mode the attractive forces are strong enough so that there is a sudden movement of the tip (the snap-in) to the surface. Again, depending on the surface properties and the set point, the tip can be in physical contact with the sample. It is also important to note that AFMs have much higher resolution in the z-axis (0.1-1 nm in the best cases), whereas lateral resolution is much poorer and for irregular substrates also prone to certain artifacts (but then so are all microscopic techniques, at least when it comes to biological specimen).
  21. This is far outside my area of expertise. In order to form an opinion on it I would have to seriously review the lit. Note that the genetic link that have been proposed are not due to mutations in genes per se. That would imply that there is an unmutated baseline and disease are caused by aberrations from that norm. That is of course not the case as all extant allele variations have arisen by mutation (and recombination) regardless of whether they are linked to diseases or not. Most likely is that certain combinations are associated with a higher risk, but again, I would have to look into lit to see what the current consensus is.
  22. Also these things require lots of energy. The price for energy has not been massively reduced in the last decades, I believe.
  23. Sure, but that is not going to happen. There is always a finite amount of money and the need for distribution. And the latter should be based on facts as much as possible rather than cherry-picked data. Obviously a big part of research is even worse off: fundamental research. In these cases one does not directly take aim at diseases. However, many will argue that understanding biological fundamentals will be key to also understand effects of aberrations and diseases better. That, in turn can lead to be better treatments.
  24. Same for schools. Should better performing schools get funded better or worse performing ones? The decision will be very different depending on moral baseline (e.g. "we want a level playing field", "we should reward success", "we have an obligation to counter socioeconomic problems" etc.).
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