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Kaleun96

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  1. I've never photographed a gold coin so can't add much specifics to this discussion but I can highly recommend the book Light Science & Magic: An Introduction to Photographic Lighting to help with problems like this. It touches on many aspects of lighting for a range of materials and desired outcomes without getting overly technical or going into too much detail. The examples are well documented with example photos and diagrams so I find it easy to jump to a specific section of the book without having to read everything that came before it. For this situation the advice would probably be similar to what has been said already but it'll help you hone in on achieving that specific lighting, e.g. what range of angles your light needs to be at relative to the coin and give you some tricks that you can try to balance the ratio of direct vs diffused reflections. Concave coins are definitely tricky, it's hard to balance getting even lighting across the whole surface without making the coin appear too "flat". So I would probably use both high-angle non-diffused lighting with a mix of diffused lighting that can reach all the parts of the coin. It shouldn't matter much whether you're using flash or LEDs or sunlight, the control of brightspots/over-exposure is entirely up to you, it's not ingrained in the light source. Similarly with the background, the colour matters little if you have control over your camera. The direct light will be your "key" light, i.e. the one providing the main source of reflections and is contributing the most to the look of the resulting image. With a concave coin, it will likely make some parts of the concave edge opposite the light look different to the edges closer to the light, simply due to the different angles relative to the light (one way to avoid this is with axial lighting). So you would then use your diffused light, the "fill" light, to help balance that out so there's not such a big contrast in the exposure of the edges but you don't want the diffused light overpowering the image and filling in all the shadows. Oh another thing you can do to help with getting even exposure from the concave edges is to tilt the coin towards the "key" light so that the surface of the coin is no longer perpendicular with the camera. This might require focus stacking due to the increased "depth" of the coin but it's what some auction houses use to help get high angles of reflection without using axial lighting (for example, see this commercial setup that some auction houses use). edit: I see a free PDF version is available online hosted on someone's website but I'm not sure if this is being shared legally so won't link it directly here. It was the third result on Google for me. I'll reproduce one of the figures from it below to illustrate what the book is like for those interested. This particular figure explains how the angle of the light relative to the subject doesn't necessarily determine whether the reflections will be direct/specular or diffused, instead the distance from the light to the subject needs to be considered to know what reflections you will ultimately get.
  2. A friend knew someone with a copy of the Elder plates and was able to get some better photos for me, including of the reverse this time, to confirm the match beyond all doubt:
  3. Classical Numismatics was kind enough to make a video on Alexander tetradrachms based on a few videos I had taken for my 2023 Top 10 list. I love being able to share part of my collection this way and it's great how Classical Numismatics is so often building his video essays around coins that everyday collectors like us have rather than just those in museums or feature auctions. He also managed to tie-in a few of my other coins that are tangentially related, like the Alexander-type tetradrachms in the name of Philip III and Seleukos I, as well as a Philip II tetradrachm. There's one correction to make for the coin at 7:00, this one is actually from Kalchedon and is a posthumous type. The coin featured at 12:00 was one of my favourite pick-ups of 2023, not only because it's a lovely example of a tetradrachm from Amphipolis but also because it's ex. Edward Newell, one of the most important numismatists of the 20th century. Though up until last week, I could only go on the auction house's word that it was ex. Newell, who were in turn relying on a Spinks auction from 1982. The best theory was that the coin was sold in the Parke-Bernet auction of 1968 which auctioned off some of Newell's estate that didn't go to the ANS, after which it was sold at Spinks and then at Noonans last year. But a few days ago I spotted it in the one plate from Thomas Elder's "Remarkable Collection of Greek Tetradrachms" that is available online, where it is coin #4 from Plate I. Thomas Elder had acquired something like 1,000 tetradrachms from the Demanhur hoard shortly after it was discovered and brought them back to the US. He then published 6 plates cataloguing 300 of these coins circa 1910 and Edward Newell then bought many of these coins from Elder, as he says so himself in Demanhur: So not only is this coin all but confirmed to be ex. Newell, it can also be said to be from the Demanhur hoard (which was suspected anyway), ex. Elder's collection, and also plated in Elder's work.
  4. I don't see what the problem is, just post the coin and share your opinions and everyone can make up their own mind. If the auction house has rebutted some of your arguments, it'd be of course fair to mention those as well seeing as it's unlikely they'd comment here themselves. As long as you do it respectfully and fairly, there should be no issue, especially after you've already contacted the auction house privately first to give them an opportunity to weigh further evidence. Since there still remains a disagreement, I would just post something along the lines of "The auction house says it's from this mint for x and y reasons, I disagree and think it's from this mint for this and that reason". No harm, no foul. We're allowed to publicly disagree with auction houses, especially for types that lack a robust attribution. Academia doesn't pussyfoot around like this, no reason we must either and I bet we can be a lot less snarky while we do it compared to many academics.
  5. "Unlabeled AI tools are unlikely to work ... Coin images will need some labelling, starting from 'this is an ancient coin'" You of course need to do some data cleaning beforehand, as you do with any kind of die study, but this is not what is meant by "labelling". Labelling would be identifying the dies in advance and validating the performance against a test set. When we're talking about training an unsupervised model, we mean feeding it images of coins you want it to cluster together based on similarity. So there's no step where you need to tell the model "this is an ancient coin" unless you plan on feeding it images of bananas or cats. " And here we have 100k+ ancient coin types for labelling!" Perhaps there's a misunderstanding. From your reply I get the impression that you're thinking of some generic AI model that is capable of producing die studies for any coin you feed it. That's not what I have in mind nor is what most people have in mind. Maybe one day it will be possible to just feed a massive set of images to a model and tell it to identify all the dies but that's neither necessary for ML/AI die identification to be useful nor the intended use case currently. What the current models are proposing to help with is the following scenario: you have 10,000 images of coins of a particular type or series that you want to do a die study for. You scraped/downloaded these images from some database that contained other information, such as the ruler and possibly type attribution. You've gone through and cleaned out the irrelevant results, tidied up some of the attributions, and now you have 9,700 coins to perform a die study on. The next step is either to do a manual die study or feed these images to a model. You've spent a long time cleaning the data but the die study itself is going to take even more time. This is the point the model steps in. You'll want to train the model on specific types or groups of related types (i.e. similar obv/rev designs). But this step is not some additional step that only an ML model requires - you have to identify the types in advance for any kind of die study. So in short: no one is proposing to feed an ML model a trove of random coin images. The data cleaning and organising aspect of die studies isn't going anywhere anytime soon. You still need to know some basics like the dataset contains coins of the same emperor/ruler/iconography and are either the same type or multiple similar types. That data cleaning and processing does take awhile but the actual identification of dies takes a significant amount of time too and it's this specific part that supervised or unsupervised ML models can help with. That being said, you can absolutely have fakes/duplicates/misattributions in the dataset and not cause any significant problems - these will be easy to identify and remove once the model attempts to cluster them or will be part of the general post-clustering validation. You can find an example of an unsupervised model for die identification here: https://www.researchgate.net/publication/356710176_Unsupervised_Statistical_Learning_for_Die_Analysis_in_Ancient_Numismatics Once a die list is known for each coin type, like some Syracuse masterpieces, do we need AI to link a new coin? I don't exactly get your line of reasoning here. There's not a dichotomy where we have to commit to either only using AI or never using AI. If all the possible dies are known then whether you need/want to use AI to identify the die of a new coin is entirely up to you. It may help for types with a large number of dies, and it'll definitely help when processing a new hoard even if there are no new dies in the hoard. Picture a hoard of 30,000 Athenian tetradrachms - would you prefer to go through the list of, say, ~1000 known dies and identify the correct die for each one, or would you rather a model do that work for you?
  6. Since you said AI is unlikely to help currently and then listed problems with die studies that would also apply to AI models, I assumed that those were reasons why you think AI models would not help currently. But if those are just general reasons, what are the reasons for why you think AI models specifically aren't yet useful? I think these models are an emerging technology when it comes to die studies but I don't see any inherent limitations that mean they aren't yet useful. The main problem is that most people capable of a die study aren't statisticians or proficient in coding and we're probably a little ways off from a generic model being useful for most coin types, meaning bespoke models trained or optimised for different sets of data is still required. On a dataset of ~450 coins, I've probably spent half the time invested just identifying dies and as mentioned the time to check one die increases the more examples you add. A model could check a new entry's dies against the rest of the database in milliseconds, and at the least probably rule out the vast majority of possible matches and leaving just a couple close matches. The only reason I haven't tried to make a model myself is that it requires upfront investment to learn that aspect of machine learning and I've already done the bulk of the die matching. It's been in the back of my mind to try one day, maybe when I start a new die study from scratch.
  7. You shouldn't need to tell the model what to focus on per se, it can work that out itself. There are tweaks you can make so it doesn't focus on the wrong thing or you can add weights to certain features etc, depending on what type of model you employ, but theoretically you wouldn't need to be that familiar with the coinage. Being familiar would help with the validation and optimisation of the model though. You may need some sort of training dataset to validate the model on and that would require manually die matching some examples and then checking accuracy but it's probably possible to do this completely unsupervised too. You feed the model the images and it learns the differences, you then make tweaks to make sure it's identifying unique dies rather than examples, and then manually check its results after. I don't know whether supervised vs unsupervised models are more common for die matching but I don't see why both wouldn't be possible.
  8. A lot of those points would apply to manual die analysis using only photos too, which a lot of die studies these days rely on. But I also disagree with some of them. For example, getting records/images can be as fast as a script that scrapes a database or polls an API. If you're recording them by hand then yeah it will take a long time but you can also download 10k records in a matter of minutes depending on the source and data quality. The problems you mention like multiple photos of the same coin, poor image quality, or tooled coins do mean manual validation or data processing is always required or at least recommended. But a die matching model could also theoretically flag identical coins and once the model has identified coins by their dies, it's much easier to manually filter out duplicates or invalid results. These are problems I've faced when die matching manually from photos and having a model go through first and do some clustering would speed up the process significantly. I think these models are absolutely the future and will unlock die studies previously deemed impossible/too tedious. Manual validation will remain part of the process but 90% of the work could be done by models in a fraction of the time a human can do it and then the remaining 10% is pre-cleaning the data and validation.
  9. I think you have to be a bit careful drawing any conclusions so early into the year and also from specific auction houses/dealers. January is a feature auction month and e-sales tend to be a bit weaker following them. We all know what's going on with Roma. Re: Leu, a lot of their inventory appears to come from hoards so you see some big swings in trends for certain types of coins. But excluding hoards, large consignments can dominate an auction house's calendar for half a year or more and we may never know it if the consignors choose to not use a collection name. An example of this for my own collection area is the Don T. Hayes collection that CNG has been selling off but his collection included a lot more than just Alexander tetradrachms. CNG started selling them in March 2023 and it's still going, though it feels like it's dying down a bit Certain dealers also often get a sudden influx either from a consignment or hoard. Regular collectors also might be less likely to have consigned their coins in Nov/Dec last year than at other times during the year So I think it's just the normal ebb and flow. Sometimes I'll go months without buying a coin from CNG or Leu just due to the kind of coins they're consigning at that time. I just assume that while those sales may not be interesting for me, I'm sure they're interesting for someone else. Those other people are probably glad that finally these auction houses are back to selling coins they collect, while for me those previous sales were perfect for me.
  10. This is just what the DHL rep told me, they'd not cover the loss of any goods considered to be antiques, which included collectible coins older than 100 years. I can only find reference to this for DHL Freight and DHL eCommerce services. I can't see any terms and conditions for DHL Express that explicitly exclude certain goods from the insurance for that service but I also didn't look for too long.
  11. Hopefully I'm not derailing the thread too much from the intended purpose but I have always wondered how auction houses offer insurance on shipping. From my understanding, both DHL and FedEx refuse to insure ancient coins (at least when I have asked), as well as my local national postal service. So when I sell coins I always explicitly state that they're not insured even if the shipping option I used says insurance included. I believe some auction houses have insurance provided through a third-party rather than the carrier. It's possible this auction house is doing the same and hence the arbitrary doubling of the price and lack of insurance on a FedEx parcel, or they're offering their own "insurance" by working out how much $$$ they lose in lost packages each year and how much they would have to charge for shipping to recoup that expected loss.
  12. I think it's likely pitting from corrosion rather than casting bubbles too. It's not too uncommon to see on a lot of the low budget Alexander drachms we see coming to market on biddr. In terms of Zurqieh, I wouldn't say they're unlikely to sell fakes as they absolutely have (and removed them when alerted) but they're probably better than your average budget biddr auction house. They have the help of a reputable numismatist for checking attributions and authenticity I believe but even one fake that I know of has slipped past him and it was a known forgery.
  13. Congrats on nearly getting the map and timeline done! Always cool being able to visualise your collection in different ways. Re: the timeline chart, as you mention it's not ideal for some devices yet due to the page width. One thing that helped me with scaling my own timeline chart on narrow-screen devices was putting the chart in its own container with overflow-x set to auto, that way the page itself doesn't stretch in width but the user can still easily scroll across the width of the chart 🙂
  14. 50% unsold at this point sounds about right for the last few Buy or Bids from HJB. I think you have to go back two years or more before you find the Buy or Bids that used to see huge numbers sold in the first few hours. Every time you would refresh the page, another couple of coins would be sold. It was a mad rush to go through the catalogue before all the good coins were sold, only hindered by their slow servers (which have gotten better) and buggy website (which is about the same). My run of not buying anything from a Buy or Bid after is nearly up to 3 years now, and that was after I bought five or six coins in them between 2020-2021.
  15. It's always a possibility but I think its likelihood depends on the type of coinage - do you have 31 examples of the same Alexander III tetradrachm by any chance? The frequency of dies, die pairings, types, examples, availability in public collections, and prior research affect how likely it is for someone to amass such a collection so what makes sense in one field of ancient numismatics may not in another. If it were a die study, we likely would've seen that die study published before they sold the coins and we'd expect to see provenances. Perhaps they did it for personal reasons (or didn't finish it), you never know, as I haven't come across such a study myself and I've also yet to see a recent (i.e. not Newell etc) die study of Alexander III tetradrachms that came from the author's large personal collection. All the ones that come to mind rely on a mix of public collections, hoards, and auction results. Additionally, this "collection" doesn't represent every type from Aspendos, Phaselis, and Perge and I bet it doesn't represent every die of the types it does have either. So it would seem to me odd to have four of one type, including of the same die, but none of others. It just doesn't strike me as a personal collection at all, unless it came from someone who bought it as a hoard themselves.
  16. I think they relied on both the historical context and the skeletal remains for parts of this. They don't have enough to make conclusive determinations as they do for some of their claims IMO. Their paper is laid out as "we determined this from the skeleton and found that it supports these individuals based on the history" but that doesn't mean their research occurred in that fashion. Almost certainly it didn't - they were aware of the historical context when assessing the characteristics of the remains. As I've mentioned I've largely forgotten what I studied but I can try and provide some more context around what the study says: "[Individual 2] Sex determination was based on facial remains. The supraorbital region of the frontal bone is smooth with no signs of any supraorbital ridge, and the orbital edge is thin, indicating that it likely belonged to a female individual" The supraorbital region is a useful indicator but it's one of about five indicators used from the skull, others being the eye sockets, the chin, the jaw, and the mastoid process. Here they only have two characteristics to evaluate and (again IIRC), the mastoid is the preferred trait from the skull for sex determination. "[Individual 1] The eruption of M3 is about twelve years later than that of M1 so that the male is expected to be a middle age adult. These observations are consistent with a Philip II and Cleopatra identification of Tomb I" Touching on age briefly, I think their logic here sounds reasonable but I don't think there's enough evidence to say it's definitively a mid-40s individual (Philip II) vs a 39 year old individual (Philip III). It probably leans towards slightly older, and their other paper said the age estimate is wide but centres on ~45yo but it's difficult to age a skeleton with high precision at this point in its life (i.e. well past the onset of adulthood). I think it's consistent with being either Philip II or III, probably more likely II but to say "the Philip II/Tomb I hypothesis is confirmed" is a stretch. Their older paper goes into a lot more detail on the sexing and ageing and I think the sexing for Individual 1 seems fairly robust, less so for Individual 2. As mentioned the ageing for Individual 1 is helpful but not conclusive and they hand-wave away it being Philip III or Amyntas III. They say Amyntas was in "advanced age" but some estimates I've found suggest he may have only been around 50 when he died. The authors cite their 2008 paper in regards to the "advanced age" claim but it also goes uncited in that paper, they just say Amyntas was too old to be the Individual in Tomb 1. So what I mean by them relying on the historical context when making determinations about age and sex is that I think they're possibly letting the history bias their interpretations of the skeletal remains. I'm not saying it necessarily a conscious bias, it could be subconscious, but when it comes to assessing these various traits and signs from skeletal remains, you have to be as objective as possible to not see what you want to see. It's tough to do properly because anyone who knows anything about the tomb is going to come in with some ideas about who is thought to have been in each tomb. Would they have made the same conclusions if we had no idea who the occupants were? We'll never know. But it is entirely possible that the individuals in Tomb 1 aren't even the ones who were originally interred in it. In the best case scenario where these determinations are done blind of any additional context and with complete remains, they're still far from perfect and can be subject to significant observer error. I'm sure you also picked up on the academic "fighting" between the authors and those of another paper. The authors don't try and hide their animosity, there's a lot of snark from both sides. That's never good and it also left me with the impression that there's a possibility they're letting the historical context and their previous research guide their interpretations beyond what can be supported by the physical evidence. But just to be clear, I'm not making any accusations or statements of fact. I just think it's a very touchy subject, ripe for bias to creep into interpretations, and I wouldn't be surprised if someone rebuts with an equally convincing sounding argument in another paper.
  17. I think there's likely some truth to that and in my experience consignment terms from other auction houses ask similar questions of the consignor. That being said, I don't think it covers Leu all that well legally. They do have some responsibility to do due diligence and if they're receiving a consignment of 30 coins of a similar type, condition, and appearance, I don't think they would get away with arguing that (a) they didn't suspect the coins may be from a hoard, and (b) that more probable than not the hoard was discovered post-2005. Even worse than the Aspendos staters in this upcoming sale are the Alexander the Great tetradrachms. I think I counted nearly 40 examples representing 10 types from the range Price 2990 to 2999 (i.e. closely related types from the same mint). Even without including the context of the other ~150 ATG tetradrachms, this kind of sample doesn't strike you as your typical collector's consignment, even if that collector happened to not only focus on ATG tetradrachms but ones of that specific mint and period. Who needs four examples per type? Many of them probably of the same die pairings too.
  18. Thanks for sharing! This is/was right up my alley as back in university my honours thesis was on using statistical methods to determine sex from incomplete skeletal remains, though I've since forgotten most of what I had learnt. After a quick skim through the paper, I would say that the historical context for these tombs is doing a lot of heavy lifting in verifying the age and sex of the remains. Even with complete skeletons it can be difficult to say with a good degree of certainty whether a given person is male or female and in this case we're dealing with some scattered fragmentary remains or partially cremated remains. The leg wound for the skeleton in Tomb I definitely seems significant though, as it aligns so well with historical sources. That's not to say we shouldn't use the historical context to help form conclusions, only that we should be a bit wary about relying on them too heavily and be clear in the inherent problems of doing so. It seems that in the past this has happened with these tombs (e.g. the supposed eye wound in the cranial bones of Tomb II). It's also easy to get caught in a tautological trap where you say the bones are believed to belong to individual X because the historical sources support it and the historical sources are accurate and reliable because the bones of individual X support them. So rather than the evidence from the tombs providing strong support for the historical narratives or vice versa, I think the reliability of both exist instead on a bit of a shaky middle ground. Though out of the two, I think it's clear the historical sources are doing more to influence the analysis of the tomb than vice versa, which leaves open the possibility that if the historical material is inaccurate then the conclusions about the tomb could change significantly too. Throw in the issues with the confusion over which material belonged to which tomb (as well as some missing material) and I get the feeling this is far from the last we'll hear of studies on the identities of the remains in these tombs. On another note, I wonder if any of the teeth are in sufficient condition to derive age estimates from. Teeth sort of have growth lines like rings in a tree and you can count them to help determine how long the tooth had been growing and estimate age at death. I know traditionally that it has required some destructive testing (taking histological slices) but back when I was still at uni work was being done to correlate that with perikymata, which are the surface representations of these growth lines, so an age determination could be made non-destructively. Either way, will dig into some more later. Super exciting to see more and more research being done on these tombs and the conclusions as presented in the paper sound pretty reasonable so far.
  19. I've got some examples to follow-up my earlier post that talked about the second reflector to get some light hitting the coin from the opposite site. These aren't the fairest comparisons as the old photos may have been lit with additional lights and not only using my previous pseudo-axial ringlight and the coins have noticeably toned since then. Aspendos staters are also relatively flatly struck so aren't the best for showcasing depth but these are a coin I typically struggled with for this reason and I think the new photos make some definitive improvements. The only thing I might change is making the newer photos a touch brighter but otherwise I'm quite pleased with them. Old photos = top / black background New photos = bottom / transparent background Photos of the new device with the second reflector on the other side.
  20. I definitely notice the axial and pseudo-axial method makes it harder to get naturally-lit edges in my photos as well. Bit of a pain because it can be tricky to light them without them standing out too much. By the way, why do you have to cut out the edges from background if your photos will always be on a black background? I used to darken the blacks around the edges when I was saving them to black backgrounds but I just relied on Lightroom's auto-mask on the brush to do that.
  21. Interesting to hear! Great that the eBay glass worked out for you too. It's certainly the best I've yet found. Let me know if you come up with anything for the background separation issue. I went down a complicated rabbit hole by using an LED light from under the coin to provide separation. It ends up being similar to the axial light problem but in reverse: you need the light rays from the background to be perpendicular to the coin or else the light will bleed into the coin's edges and blend it with the background slightly. My current solution works great except for a minor focus stacking related side-effect but if you find an alternative solution I'd love to know as it may nullify that issue. I guess an obvious solution is just distance between the coin and a static background that you light separately. That would avoid reflections onto the coin edge if the distance is sufficient. Unfortunately in my case I don't have enough room for that separation.
  22. Just a minor update this time. So with the angles involved it's difficult to balance getting enough light on the coin at a high enough angle that it will reflect back into the lens after bouncing off the coin. Higher angles tend to mean less of the light can be reflected onto the coin because the geometry simply doesn't allow it but if you use lower angles, you get more light bouncing off of the coin but lose the axial effect and most of this light is going to bounce away from, not back to, the lens making it wasted light. In one of the diagrams above I mentioned that I designed a "blocker" to prevent some of the reflected light from exiting the device because it will never reach a coin of the diameters I commonly photograph. In the screenshot below, only the light that is allowed to reflect onto the coin is shown and is depicted by the yellow highlighted areas. Behind that space you can see an empty rectangle of sorts, this light would reflect off of the first surface and then hit that triangle shaped blocker between it and the coin. So you can see I am wasting a fair amount of light but it's not that I necessarily need it either. It would be useful, though, if it can be used to light the coin from the other side and at a similar angle. I worked out that this should be possible with the right angles and came up with this: So the original reflection surface now has a secondary angle at the back, which previously just reflected light to nowhere. It now reflects the light horizontally (shown in green) across the device to a third reflector, which reflects it towards the coin at an 80 degree angle - same as the light reflected on the other side. I'm hoping this will give me a more even axial effect across the coin instead of the majority of that effect being seen on one side of the coin. I've also mounted magnets in the reflectors so that they can be removed and swapped out, in case I don't want this secondary reflection. One issue I had when initially testing this was that the white plastic reflectors really do not reflect a lot of light. The two reflections required for this secondary reflection (green) meant almost no light actually reached the coin from this side, only from the original side. I then tried covering all the white reflectors in aluminium tape, which has a mirror-like finish, but that reflected too much light! My flash was too powerful at its lowest setting when using the aluminium tape reflectors. So instead I used the aluminium tape on just the initial reflection surface of the secondary reflection to get enough light across to the reflector on the other side but I left that reflection surface and the original reflection surface as just the white plastic as that seems sufficient for now.
  23. Thanks! I wouldn't put too much stock in the edges in these comparisons as that's something I edit in post. Since I use transparent PNGs for the photos on my website by removing the background, I use an edge lighting diffuser to capture detail in the coin's edge otherwise it'll be entirely black and that doesn't look good on bright backgrounds. I then control the edge brightness in Photoshop using inner shadows to dial the brightness back down and add some natural fall-off. I actually forgot to use the edge diffuser on PA-2, which is probably why it seems darker, though I had to manually bring the brightness up before stacking so I could capture some of the detail that was there. The main problem is that bright edges look bad on dark backgrounds and dark edges look bad on bright backgrounds, so I have to try and strike a balance as it's not guaranteed my photos will always be against a dark background. I think this is something I can also control using CSS so I can have "dynamic edges", so to speak, depending on background, though that doesn't work for when I post my photos to other sites. For the photos above I just used a black background JPG to keep the file size smaller.
  24. Part 3 Tests Time for some tests/examples. I'll start with an example shot using a proper axial light setup, i.e. with a piece of reflective glass between the lens and coin. And then I'll go through some "pseudo-axial" setups, starting with my current flash adapter, one of the new ones I made, and then a final design I've roughly settled on for now. Just to make sure we're on the same page when I discuss some particular areas below, the parts highlighted in red are my main focus. These seem to be the flattest areas of the design and areas where I want to try and capture some of the contours that are actually there but can appear flat in some lighting situations. Axial Lighting - First up is the pure axial lighting setup. There's great contrast around the designs, the toning is really brought out of the surface, and the focus areas mentioned above don't appear flat at all except for in small parts. The front leg of Baal for example is nicely rounded and the definition and depth can be seen in his chest as well as the lion's. The main negative is that the toning seems too much in places, such as the red, oranges, and blues on Baal's head, chest, and the lion's body. And as mentioned before, axial setups like this do reduce sharpness and detail, though it's practically unnoticeable unless zoomed in. Pseudo Axial 1 - This is using my current flash adapter, the one I've used for most of my photos. It's still a nice photo with great contrast around the figures and the toning is preserved but much of Baal, and parts of the lion, seem featureless and flat. Baal's chestand front leg in particular but also his arms, the lion's limbs, baal's head etc all are very flat. Pseudo Axial 2 - This one uses the black device in the bottom row 2nd from the left seen here. It uses two flashes positioned 180 degrees from each other, each reflecting light that should hit the coin at an 80 degree angle. For this photo they were positioned at 12 and 6 o'clock, i.e. top and bottom. Compared to Pseudo Axial 1 (PA1), we have less contrast around the figures but also less flatness. We get some definition back in Baal's legs and chest and the lion's shoulder, chest, and hind area represent the contours of the body just a bit better. We keep much of the toning but the surfaces of the obverse in particular look a bit more natural than in either the PA1 photo or the Axial Lighting photo. Pseudo Axial 3 - Finally we have what I think is the "winner". It's the black device in the bottom row at the far right in this photo, i.e. a single flash version of PA2. I believe this one balances the pros and cons of axial lighting best. It has the least amount of flatness out of any of the Pseudo-Axial examples while maintaining the toning and contrast. Compared to PA2, the lion has extra contrast on the underside as we're no longer lighting from that direction, only the 12 o'clock direction, but this results in much better depth being perceivable across the lion's trunk and limbs. The downside is mainly on the obverse where the axial effect struggles to make the surfaces pop near the bottom of the coin, as very little direct light can reach here and what light does likely bounces away from the lens. Nonetheless it's still possible to get a relatively evenly-lit photo while the majority of the reflected light is theoretically only targetting the top half of the coin. It can be difficult to see some of the nuanced differences from images side-by-side so the GIFs below alternate between two photos to make it a bit easier: AL1 vs PA3 PA1 vs PA3 PA2 vs PA3 If you made it this far, let me know which one you prefer! I think I'm on the right track with the last one (PA3) and have a few ideas for some improvements but feel free to send some ideas my way if anything occurs to you.
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