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Kaleun96

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  1. Out of curiosity, what is the COA from the original owner like? Is it signed by the owner, and if so are they some authority on these types of items, or is it signed/issued by someone else who is? Just wondering since, as many of us know, COAs are often worth less than the paper they're printed on. Or is it perhaps a report/statement rather than an explicit COA, e.g. a museum curator stating it's genuine to the best of their knowledge?
  2. Ah so they continue supporting the OS with security updates for a few more years? If so, that's still comparable with Windows but you're not really making it a fair comparison. You're saying Windows doesn't let you upgrade to Windows 11 while arguing that Apple provides support for another 3 years on a 5 year old device but from what I understand, Apple also doesn't let you upgrade to the latest OS. You may get new releases for the version of the OS you're on but not the new OS itself. If you look at macOS Ventura, the supported devices go back to 2017, while for macOS Sonoma they only go back to 2018. So it stands to reason that a 2018 Mac won't be able to update to macOS Sequoia coming out later this year. This is exactly how Windows works too. The way you're phrasing things makes me think you're either just ranting about Windows for the sake of it or you don't understand how updates work for Mac and Windows. You say your Windows "desktop is locked" - would you say the same for a 2017 Mac that can't upgrade to Sonoma? Will you also have to "throw it in the trash", like you apparently have to with your Windows PC? Keep in mind that there's also a difference in that Apple locks down the hardware of their computers so a particular model from 2018 is the same, more or less, for everyone. A PC is of course not like that, a computer bought in 2018 may be worse than one built in 2014. The computer hardware has little to do with Microsoft, unlike in Apple's case. The beauty of a PC in this case is that you can upgrade the hardware yourself so it can support Windows 11. It's not so easy to upgrade a 2016 Macbook so it can support the latest MacOS - I'm not even sure it's possible for the average consumer to have this work done. Windows isn't preventing you from doing anything, if anything it's the Macbook that you have to throw in the trash. Re: Chrome, presumably the same applies to Windows - Chrome on Windows will continue to receive updates too as long as Chrome supports its browser on that OS. Though I don't think that will be particularly safe in either case, the problem is with vulnerabilities in the OS and downloading malware using Chrome is not going to prevent that issue, whether on Windows or Mac. Regarding Macs being safer, I think that was true 15 years ago but there's plenty of exploits to be worried about these days whether on Mac or Windows. There's a reason every company I've worked at has automatically enforced security patches for Macbooks as well as Windows devices. I can recall more than a handful of times when we've had to install updates same-day due to a serious vulnerability discovered for Macbooks. Just to be clear, I'm not pointing this out because I like Windows more than Mac or vice versa, both have their pros and cons. The way you're phrasing the issue you have with your Windows PC is just misleading. You're not locked out of anything, you don't have to throw anything away, and Apple handles updates and OS support exactly the same way.
  3. To be fair, Windows isn't saying "throw it in the trash", you just won't get updates. This can be a security issue but it's exactly the same situation for your Mac that can't update to the latest OS. Both machines will continue to run without issue, you're just open to security vulnerabilities that won't be patched. I've used Google Docs for personal use and work for the past 10 years and personally never had an issue with disappearing data or similar bugs so I can only recommend it. Its online/cloud functionality is also much better than Microsoft's equivalent but you of course can't beat the desktop version of Excel or Word, although last I recall they have some limitations on Mac still. But the less we say about Apple's Numbers app the better!
  4. A quick check of Apple's latest operating system released in 2023 seems to suggest that it doesn't support any Macbook models older than 2018 (and one iMac released in Dec 2017). Windows 10 came out in 2015. 10 year support under Windows versus 5 year support under Apple sounds pretty good to me! I use Macbooks for work and Windows for personal use so I see pros and cons with both but personally I wouldn't migrate to Mac for their update support or their customer service. Windows has a much greater vested interest in maintaining backwards compatibility compared to Apple. In my experience, most modern tech/IT companies replace their macbooks after 3 years so backwards compatibility is rarely an issue. The companies/institutions that are predominantly running Windows machines probably keep some of them going for a decade or more.
  5. Dropped relative to pre-hoard for sure but I think prices for Owls have gone up a bit since they peaked on the market in 2021. Acsearch shows half as many owls sold in 2023 versus 2021 (2.7k vs 5.7k) and many that have been sold in 2023 and 2024 by the big auction houses that bought up the hoards (e.g. Roma) have been lower quality on average compared to 2021 in my opinion.
  6. There comes a point where replying to someone to explain why you disagree with them when they say something stupid, for example equating the actions of the average auction house with what Richard Beale has been convicted of, is often a waste of time for all involved. Not to mention that you very quickly end up derailing a thread with reply after reply when a quick "I disagree" emoji or comment would suffice. Not everything requires a thought-out response. I think people here are acting as if the "confused" emoji is used after someone has written a nice thoughtful research piece on some aspect of numismatics. Rather, the confused emoji tends to be reserved for more deranged comments, such as those about Beale, a thread with a vague numismatic excuse for posting depictions of half-naked women or other crass images, or something silly like when someone claims that the antiquity laws of other countries aren't lawful because they happen to disagree with them. If someone writes intelligently on some aspect of numismatics then I agree, simply downvoting or adding some other negative reaction is not a polite response.
  7. I never used it for trolling, only when I was genuinely perplexed by what was said. Perhaps the new "thinking" emoji will suffice. Users may sometimes post very baffling comments and I don't need an explanation of what they meant, the meaning is clear but the opinion on the other hand... Great idea, a disagree/thumbs down emoji would do just fine!
  8. Broken for me too. I'm using Chrome. I see we lost the "confused" emoji too 😟
  9. To be honest, I'm surprised to hear curators at the BM even engage with collectors on this kind of thing. Have you found it easy to get these appointments and is it because you have a working relationship with them or have published in this area before etc? Like shanxi, I'm also wondering if you posted the wrong picture since I can't see the relation between what you've said and what's in the picture.
  10. Wouldn't it be better to just be upfront with why you're calling it rare? Auction houses do this when they say "rare in this condition". Though I'm not sure that would be accurate in this case either.
  11. If I remember correctly, just some of their former employees work at Numisfitz but there's no official link or agreement between Numisfitz and Lanz. Perhaps they managed to get some of their catalogue inventory because they do sell a lot of Lanz catalogues.
  12. The post feature eSales at CNG are always strong, they're like mini-features because they have a lot of the coins that didn't fit into the feature sale. Once you know that, you know to expect strong competition. I was lucky to win my main target. It went for a bit more than I would've liked but below my max so can't complain. Aside from being a type that I had wanted for quite some type (one of the earliest Alexander types from the Myriandros mint), it's also formerly of a very special collection who many of us had the pleasure of knowing: Terence Cheesman. It featured as coin #6 in his Top 10 of 2022: Having talked with Terence a few times about Alexander coinage, and knowing what kind of collection he had built over the years, I was quite determined to have the honour of picking up one of his coins from this sale for my own Alexander collection.
  13. Glad it helped! I still struggle with various concepts myself so it's useful for me to type this out occasionally 😁 One thing I didn't mention about working distance (WD) and minimum focusing distance (MFD) is that they're closely related but just measuring from slightly different points. The working distance is the distance from the object to the front of the lens at a given magnification. The minimum focus distance is the distance from the object to the camera's sensor, which is approximately equal to: MFD = Working Distance + Length of the Lens. Both assume that the object is in-focus, so at 1x magnification there is a fixed distance the lens and sensor need to be from the object for the object to be in focus. If you dropped the magnification to 0.5x, you would need to move the camera further back and you'd have a different WD and MFD for 0.5x compared to 1x. source: https://www.sony.co.uk/electronics/support/articles/00267924 The MFD can refer to both the minimum focus distance at a given magnification but also the absolute minimum focus distance for the lens at any magnification. Usually the absolute minimum focus distance of the lens (let's call it aMFD) is the same as the MFD at the highest magnification setting of the lens. So a lens that can do 2x magnification will have its aMFD = MFD at 2x but if you dropped the lens down to 1x magnification, the MFD will be greater than the aMFD, meaning the camera is further away from the object. The magnification of macro lenses is changed by twisting the focus ring on the lens body. Most camera lenses have a focus ring but on macro lenses it's more closely tied to magnification so often lens manufacturers put the magnification markings on the focus ring (e.g. 0.25x, 0.5x, 0.75x, 1x) in addition to the normal distance markings. The distance markings typically go from infinity ("focused at infinity") down to the aMFD. For non-macro lenses, the magnification of the lens may not change substantially whether you're focused at infinity or focused at the aMFD. For macro lenses, the magnification changes a lot as you change focus from infinity (lowest magnification) to the aMFD (highest magnification). At you change the focus, and thus the magnification, of a macro lens, then the MFD also changes. The reason Working Distance is also used is because it's a bit more practical - we don't really care how long the lens is, we only care how much distance is between the object and the lens, so the WD removes the length of the lens from the MFD. The depth of field is not necessarily related to the focal length of the lens, rather the depth of field is primarily influenced by the magnification. The higher the magnification, the smaller the depth of field, meaning the smaller the amount of the subject is in focus. So whether you use a 30mm macro lens or 100mm macro lens, it doesn't really matter in terms of the depth of field, the main difference between those two lenses is that the 30mm lens may have a working distance of only ~60mm at 1x magnification while the 100mm lens may have a working distance of 150mm (example numbers). The larger working distance makes it easier for you to light the object, which is generally why people prefer 90-150mm macro lens for coin photography, though it's not strictly necessary. Ah I see perhaps where there is some confusion. It's definitely true that the closer you get to an object, typically the higher the magnification you can achieve. So I can see why you want to get as close to the object as possible. However, the advantage of a macro lens with a longer focal length (e.g. 100mm) is that you can achieve the same level of magnification while being further away from the coin. So let's say your 14-42mm lens with extension tubes allows you to achieve 1x magnification when the lens is 40mm from the coin, the benefit of the 100mm macro lens is that it may let you achieve 1x magnification while keeping the lens 150mm away from the coin. The images from the two cameras will be nearly identical (some differences due to perspective distortion) as the magnification is the same for both (1x), the main benefit is just the greater working distance allowing you to have more space between the camera and the coin for adequate lighting. As you increase the magnification, the depth of field will decrease, so you will find that a single image isn't able to capture the coin fully in-focus. Focus stacking is a way to fix this. You take multiple photos of the coin, each photo with a slightly different part of the coin in-focus, and then use software to merge the images together so that only the in-focus parts from each image are kept. If I recall correctly, there is a relationship between focal lengths and extension tubes where the lower the focal length, the less extension you need to achieve a given magnification. Extension tube increase the lens magnification by an amount equal to the extension distance divided by the lens focal length, so if your extension distance is 30mm then for a 50mm lens the added magnification would be 30/50 = 0.6x, while if the focal length was 30mm the added magnification will be 30/30 = 1x magnification. The reason you can't just use shorter and shorter focal length lenses with extension tubes (e.g. the 12mm focal length of your 12-50mm lens) is because the focus plane ends up shifting closer and closer to the lens, reducing the working distance, so at some point the focus plane actually ends up inside the lens, making it impossible to focus on the object. Definitely happy to help answer! I got all this information from the countless other people who take the time to put it on the internet so the least I can do is repay the favour 🙂 For photographers, the focal length is mainly affecting the field of view and that's what they're thinking about when deciding which focal length to use. A 24mm focal length is great for landscape photography because it has a very wide field of view. You can go ever wider, and a lens at 12mm focal length might give you a "fisheye" perspective where the field of view is incredibly wide. I believe the field of view for the human eye is equivalent to about a 22mm focal length lens. Wide focal lengths like 12-28mm lenses have quite strong perspective distortion, which makes them less suitable for portrait photography. A great example of that is this GIF: So a portrait photographer probably wants to stick to a lens with a focal length of around 40-80mm. They could use a much higher focal length lens, say 200mm, but other factors begin to become relevant: long focal length lenses are typically bigger and heavier and let in less light than a smaller focal length lens. There's also some other factors but less relevant to the current topic. Going back to landscape photography, let's say you're standing on a hill overlooking a valley a few hundred meters away and down in the valley is a small farm house. A wide angle lens like a 24mm lens may have a field of view that gives you an image the shows the valley, part of the hill you're standing on, the sky, the horizon in the distance, and the farm house way down there in the valley. If you change to a 400mm lens, the field of view will narrow considerably. We can no longer see the sky or the horizon, or the hill we're standing on, the field of view is now so narrow that we can only see the house in the valley and 20m either side of the house. So the house now takes up most of the image, whereas with the 24mm lens it only took up a small spot of the image. Therefore, we've essentially zoomed in on the house by narrowing the field of view. So that's a brief explanation of what different focal lengths are used for but field of view isn't something you may need to think about when it comes to macro photography. For macro photography, the main consideration of different focal lengths is the working distance that I mentioned above. Wide focal length = short working distance, long focal length = long working distance. And the difference between a 60mm non-macro lens and a 60mm macro lens is the ability to focus more closely (minimum focusing distance) and the magnification ratio that the lens can achieve.
  14. The theory and physics behind photography can definitely be daunting but for the most part you can ignore it and stick to the general principles. So for example, a 12-50mm focal length lens would be considered "wide"/"short" at the 12mm end and "standard" at the 50mm end. A wide/short focal length is typically not ideal for macro photography because the working distance is often very short. The working distance is the distance from the front of the lens to the subject when you're focussed on the subject at a given magnification. For a 1x macro lens, this can sometimes be as little as an inch or two if the lens has a wide/short focal length. For a macro lens with a "long" focal length like 100mm, the working distance may be 5 or 6 inches. The working distance is important for coins because the bigger the space between the lens and the coin, the easier it is to get your lights in there at the right angle. If there's only an inch or two, your lights would have to be lighting the coin from a very low angle to get around the lens that's in the way. There are two main differences between a macro lens and non-macro lens: the magnification ratio and the minimum focusing distance. The magnification ratio is the relationship between how big an object appears on the camera's sensor versus its actual size in real life. So you have a micro four-thirds camera, this means the camera sensor has a dimension of 18 mm wide × 13.5 mm high. Let's now take a coin with a diameter of 13.5mm and using your camera and lens, try to get as close to the coin so that when it is in-focus, the coin fills the height of the image. So now the coin is perfectly filling the height of the image and since we know the height of the sensor is 13.5mm and the diameter of the coin is 13.5mm, that means the magnification is 1x (13.5 / 13.5). If the coin was 18mm in diameter but still filling the height of the image, the magnification ratio would be 13.5/18 = 0.75x. But you might be wondering, why doesn't every lens just focus on the coin so that it fills the frame of the image? That's where the minimum focusing distance plays a role. Like the human eye, a lens can't focus on an object that is extremely close to it, it will just be impossible to get an in-focus image. The minimum distance at which an object can be focused for a given lens is called the minimum focus distance. Macro lens are built specifically to have smaller minimum focusing distances, meaning they can get closer to the object and still be in-focus. Your 45-150mm lens likely can't focus as closely as Aidan's 60mm macro lens. Say you set your lens to 60mm and compare it against Aidan's, Aidan can likely have his lens closer to the coin than you can with your lens, even though you're both using the same focal length. You will have to move your camera further away from the coin to get the coin in-focus and when you move your camera further away, the coin takes up a smaller part of the image. For Aidan, the 13.5mm coin may fill the frame but for you, the 13.5mm coin may be only half of the frame, which would make your magnification ratio 6.75/13.5 = 0.5x. The 6.75mm is because we know the coin is taking up half the height of the frame, and the sensor is 13.5mm high, so 13.5/2 = 6.75mm. Here's a diagram that might explain this better. The red frame is a representation of the image sensor, which is also what you would see through your camera's viewfinder / LCD screen. Aidan can get the 13.5mm diameter hemidrachm in-focus when the lens is 80mm from the coin but when you try to do this, the coin won't focus. You then move the lens back so it's 160mm from the coin and now you can get the coin in focus, but the coin only takes up half of the image frame's height (6.75mm). Since the coin, which is 13.5mm in diameter, only takes up half of the sensor's height (6.75mm), the magnification ratio is 6.75/13.5 = 0.5x, while it's 1x for Aidan. Every lens has a magnification ratio but for non-macro lenses it's typically below 0.5x, meaning you can never get the lens to focus on an object that is the same size as the camera's sensor and have it fill the image frame. Extension tubes can fix this and allow you to focus on objects that are closer to the lens, which increases the magnification ratio of the lens.
  15. If you really need the working distance, that combination might be worthwhile. Apparently the minimum focusing distance at 200mm for the 70-200 lens is 42cm, so with a 2x teleconverter you would essentially have a 200mm 1x macro lens with the field of view of a 400mm lens, allowing you to keep that massive focusing distance while doubling your magnification from 0.5x to 1x. Though there is perhaps such a thing as too much focusing distance for a macro lens and 42cm is a lot. I think for the 100mm Laowa lens, it's more like 15cm at 1x, which is plenty in my experience. The downsides of the teleconverter are that you would take a hit in terms of sharpness and possibly introduce more optical defects (e.g. chromatic aberrations), and also that you would lose 2 stops of light. So if you're at 200mm and f/8, with the teleconverter you're effectively at 400mm and f/16, which is likely diffraction territory, affecting sharpness even more. You could theoretically drop down to, say, f/4 or f/5.6 and then you'll be at f/8 or f/11, which might provide enough depth of field but I'm not sure if the depth of field would be the same as a native 1x 200mm macro. The other consideration is if you wanted to use the lens for things other than macro, in which case it might make more sense than buying a dedicated macro lens. But if the goal is to get a dedicated macro lens, I'd go for the Sony, Sigma, or Laowa. The Sony is definitely excellent but I've heard that the Sigma is even better. The Laowa has better optical quality than the Sony but without autofocus. Supposedly the Sigma has the best optical quality of the three plus autofocus. I do like the Laowa for <20mm coins though due to the 2x ability. This one is about 15mm at its widest and I shot it at about 1.5x I think. That did require focus stacking though.
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