Kaleun96

My point was that the lack of someone's publicly available writing on coins in their collection is not a reflection on what they have written about their coins.....some people don't like to make their writing public! It's also not a reflection of the research they may do on the coins in their collection (we all probably do a little bit of research but it varies).....so why do you make the assumption that if you can't find writing by someone about their collection that they only collect coins to put them in a little tray and hide them away from everyone? Not everyone has the time, energy, or desire to write genuinely interesting pieces about their coins that further the knowledge or understanding of those coins! Only so little time in a day, that's life! Not to mention that there's a lot of writing on coins out there that is not useful for anybody.....whether because it gets things wrong or because it's difficult to read and understand! What is research? Is it some scribbled argument self-published online or a properly constructed and peer-reviewed original piece of work providing insight on a topic published in some reputable outlet? What is curiosity? Is it the publicly available accounting of one's research, understanding, and insight of a coin, or can it be one's personal journey from purchasing a coin, to researching and attributing it, and beyond? Ok, sarcasm over. I think I know who you really are thinking of when you share your frustrations about "collectors" who only collect. It's the Museo Chieti Italy types (apparently), the rich collectors who buy an important coin and forget about it in their safety deposit box, the types who have no interest in potentially helping other collectors because they're not really interested in numismatics, only old and shiny metal objects that are potentially worth a lot of money. The problem is you're frequently all over the place in your writing and (inadvertently?) make generalizations about a large portion of collectors in this hobby when you probably only mean to speak of the aforementioned "types" of collectors. Perhaps you do mean to target everyone who hasn't setup their own academia.edu page when talking about the uncurious, shallow, and greedy collectors depriving others of knowledge. I honestly can't tell, just giving the benefit of the doubt.

Not everyone has the time. To what level must one write about their coins anyhow? Do they need to publish in a journal or is it sufficient if they put to paper their stream of consciousness about a coin and upload it somewhere publicly available? I wouldn't have thought it needs to be publicly available but you also don't want to be called out for not writing about your collection.

That's all fine but, again, I'm not wanting to get into the specifics of how and why you manage your collection, I only was mentioning that you already have some system and may have secondary uses for that system (apparently not, but not important) that may create friction and prevent you from being able to use an off-the-shelf solution. But someone without those secondary uses has less friction when wanting to move to a different system. There's of course varying degrees as to how much friction a "secondary use" creates, in my case it would be a huge amount of friction, but in other cases not so much. SaaS products tend to be focussed on particular types of users, so my point was that you, I, and some others here, may not initially be in that target user group for OP and thus when we say "you're not solving a problem I have", it's not necessarily relevant to what OP might be trying to do. Agree on putting a v1 out there, that was going to be my initial feedback in this thread but others covered it well enough. I'm not proposing OP develops some automated syncing tool for coin data to a person's respective website. I don't imagine OP would initially want to target users who have existing websites, unless it's to convert them to whatever tool is being built. Later on it would be easy to expose an API so a user could use OP's tool as management software and easily fetch that data to bring into their own website where they might do other things with it but would many use it? Probably not. I'm not harping on about moving data, you were the one to get stuck up on it. I only mentioned "feeding data to your website" as an example of something you might be doing. It was my mistake to assume that you might be doing this but it was no slight on you so I'm not sure why you took offense to it. Re: auto-generation (not sure why auto-generation of code is relevant here?), I was only taking exception to your characterisation that syncing data to your website has no use because you write stories and autogenerating stories is a bad idea (I agree). But there's many genuine reasons you might want to sync data to a website whether your only content is writing stories or not.

I think the issue here would not be the model so much as the data cleaning. For example, you can refer to SNG BnF Cilicia in so many different ways: for SNG you have SNG and Sylloge Nummorum Graecorum; for the first suffix you have Bibliothéque Nationale, BnF, France, Paris, BN (maybe others); and for Cilicia you probably use either Cilicia, 2, Vol. 2, or some combination of them. Not to mention all the different characters you may get between them, like: SNG (BNF) 2 1402, SNG Paris (2) 1302, SNG France 95 (now you have to look-up which volume it's from based on the mint), and so on. You could handle 95-99% of cases with some regex but this is just for one publication, you'd need other regex for other publications, particularly non-SNG ones. A model may work given you've gone and labelled a large chunk (thousands) of it first to train it on. But you would also need a pipeline to have gone through and identified the mints, so you can do the look-up on the SNG volume if not provided - and if the SNG volume is not provided, you have to be able to identify that it's not provided, which probably assumes a single set of integers following a known SNG publication "phrase" refers to the type number and not the volume number. You could do that by looking for a set of integers that is ended by a full-stop, new-line, or some other character or punctuation. But then you risk missing out on SNG France 2. 1403, which refers to Vol 2 but Type 1403. Okay, so then you allow for two sets of integers that are separated by one of a set of known punctuations but doing this you could introduce errors where the volume is not provided but the Type number is followed by a full-stop and some other, irrelevant, number. But perhaps this can be solved by knowing the number of volumes for each publication and only allowing the first set of integers (likely a single integer) to represent the volume, if the integer is out of that range then it must be the Type and not the Volume, and any set of integers then following this one are definitely not related....unless a range of Type numbers are given, such as SNG France 1403-1405. Okay, so we'll allow for hyphens and a select few other characters that may identify a range of Type numbers. Ok, we've solved that one (for this publication), let's get back to identifying the volume when not provided based on the name of the mint or region. What happens if the description contains more than one mint/region name? What if it's not spelt correctly or uses alternative spelling? Maybe not such a big issue compared to the previous one but this is another pipeline/data flow that needs to have been setup, validated, and integrated with the main model. Anyway, you can see where I'm going with this. In my experience, the difficulty with ML/AI is not the model but the data, and validation, handling, and cleaning the data takes up the majority of the time, resources, and effort. Letting a model work out all the difficulties and nuances is probably the "easiest" way but think how much data you would've need to have gone and labelled to get a good representation of all the major publications and their variations in spelling and formatting? I could see it being do-able for, say, just the SNG publications, but since there's little convention in publication attribution, it would take a lot of labelled data to have something that works well generally. I'm sure there's some cutting-edge NLP method that may avoid some of these issues but then you're talking about hiring some expensive people.

Not sure if you're replying to my comment addressed to you but as I talked about feeding data into our respective websites, I'll assume you might be. Anyway, I didn't say you had a complex system, I only said that you (we) have customised solutions for our own needs and that includes a secondary need of being able to upload that data to a website - even if that is manually copying it over as you suggest you're doing. My point is not in the details of how you manage your collection, my point is that just because *you* don't see a need for it, doesn't mean that need doesn't exist. You're already likely in the top 5-10% of collectors when it comes to having something to manage your collection digitally, even with something as basic as a spreadsheet. If you're fine with managing data that way and copying it over to your website manually, then of course the value of such an app is minimal for you and there's no reason to change what you're currently doing. However, a lot of people may not be so keen on managing their collection in this way and might pay for the convenience of a user-friendly app/site that makes this easier and provides other features. Also, I think you know this already as someone working in software but there are other reasons (besides "autogenerating stories") for not wanting to manually move data between systems. Whether it's overkill or not depends on the needs.

That's a pretty nifty bit of software, $50 is perhaps a bit steep for many but at least it's a one-off cost and comes with a mobile app. Can you create inputs from formulas like in Excel/Sheets, e.g. a field is generated by the values of several other fields or anything like that?

@mordehaus I love that you're attempting to tackle this problem, I've thought about it a lot myself. I have my own website to manage my collection and build the tools I want to make my collection easier to use/manage/view, but this only works for me and I wish there was something similar for everyone. It doesn't need all the bells and whistles but basic/intermediate things like: a gallery, a map of where your coins are from, a database/catalogue tool to see all the details about your coins and filter on them, basic charting tools to take advantage of data about the coins (e.g. comparing weights vs diameters), high resolution image hosting (none of these 250kb size / 1024px resolution file limits), converting invoice amounts to a common currency using historical exchange rates, a calculator for estimating final invoice price for a given auction house, tools for quickly sharing your coins to third-parties, or even allowing you to publish your collection to a centralised place on the platform, and maybe a tool that uses some third-party API to automatically remove backgrounds from your photos. As you say, it feels like we're living in the mid-2000s when it comes to the currently available/recommended tools and solutions (e.g. desktop inventory management software 🤮). My advice would be to aim for either the younger demographic (<35) or collectors who are new to this hobby (<5 years of collecting). People who have been collecting for 15 years are probably going to have some solution. It likely won't be a particularly good or modern solution but it will work for them, it will be integrated with their habits, it will be incredibly customised to their specific needs, and they will know how it works inside-and-out. Frankly, you're not going to have much hope of converting a collector like this to a new tool that will start off as being relatively generalised and lacking in functionality. But that's ok because the vast majority of collectors at the moment are probably not in that group I've just described. There's been a huge influx of new collectors, or collectors coming from other numismatic areas, in the past few years and this is probably the best demographic to target. The difficulty with them is that they may not yet see the need for an online tool or app that let's them manage everything in one place. For starters, they'll have to have enough coins to make that a problem worth solving. So any benefits from having all your coin info in one place, or your invoices backed up in the cloud, etc requires a significant investment in the hobby before these features will pay off. But there could be some other things that don't require a lot of coins to get some benefits from, such as a few of the suggestions I mentioned above.

Personally I disagree with this assessment. Granted there are a lot of people here (yourself and myself included) that have their own solutions that work for what we need it to do, it's usually because we have some secondary purpose, such as feeding that data into our own websites. An off-the-shelf solution that has been designed for generalised use is not going to help people like you and me in this case but these kinds of tools aren't aimed at users like us, at least initially. There are far more people who do not manage their coins to this degree, who may not even keep a spreadsheet of their coins and purchases, yet are tech savvy enough to understand the benefits of such a tool being proposed and how to use one. I'm probably thinking more of the younger demographic here but I would wager the vast majority of young collectors would have no problem using an online inventory tool for their collection, and probably don't have anything sophisticated themselves (based on my experiences), the main issues would be with getting them to pay for the tool (who isn't already paying for a dozen subscription services each month?) and having a tool that fits most people's general needs. There are a huge number of collectors out there that do not frequent these forums, or if they do they don't respond to these types of threads about "how do you manage your collection" etc, so it's easy to fall into the trap of assuming everyone has their own solution that works perfectly for them and there's no room for improvement or wider demand for such a tool. And while it may be a bit harsh to say, it does need to be said that a large number of solutions that people currently use for managing their collections are either woefully out of date (e.g. forumancientcoins user galleries, or any forum-based gallery for that matter) or impractical for the vast majority of collectors (e.g. MS Access or other custom databases like my own). Google Sheets or similar is great for what it does but it doesn't make it any easier, for most people, to leverage that data in a useful, accessible, or visually appealing way. So in my opinion, there is definitely a need for a modernisation of collector's tools but it will be difficult to execute in practice. It's perhaps a bit cliche to say but it is a bit similar to pre-Spotify days where you get a small group of people who have their own particular workflow that works exactly as they need it to (e.g. PirateBay or ripping CDs, managing their own music library and folder structure, cleaning and curating the files manually in iTunes or WinAmp) but the majority of people simply don't have the time, energy, or desire to put in that investment. The former group doesn't need a Spotify but they can benefit from it once it gets to the point where it has most the functionality they need but massive increases in accessibility and time-saving.

I've found consigning coins once a year or so to be a refreshing process for my collection, kind of like slash-and-burn in farming. It gives me a good opportunity to really consider what I would miss having in my collection and what I could live without. Selling these coins then frees up spaces in my trays, gives me new budget to work with, and helps me focus on what I really want to collect versus what I might end up consigning in a year's time. So far I've yet to regret any coin I've consigned. I try to make a draft consignment pile and separate them from my collection for a few weeks to give me time to see if I miss them or whether I should add any other coins to the consignment.

Great video Leo! It's a topic most of us here and probably familiar with but it was interesting to hear your descriptions of the three archetypes. Near the end I think you talk how one should really think hard about whether a coin belongs to one's collection or not when deciding whether to consign or sell it etc. What I've found a bit interesting in my own journey is that I often find that the coins I buy for a sub-collection are often the ones that move fastest from sitting on top of my coin cabinet to being sorted away in one of the drawers. That's probably because collecting for a specific theme can mean buying less common coins that are in middling condition and thus don't always have a lot of in-hand appeal. The other coins I buy, that don't fit a sub-collection, I really try to focus more on getting ones that do have great in-hand appeal, and those tend to stick around longer on top of my coin cabinet and within arm's reach. The flip-side to this, though, is that I spend a lot more time reading and researching about coins related to my sub-collections, while the "miscellaneous" coins I buy from outside those areas may get more in-hand attention but a lot less "academic" attention. Not to say this will be the case for everyone, just something I've noticed when buying coins myself.

Haven't shared anything photography related in awhile but have been busy with some small improvements to my flash adapter. Might post about those improvements soon if I get the time. One thing I wanted to quickly mention, and that I think I started this thread with, is about the mirror-as-a-background technique. It's still serving me well, albeit with its limitations (if you want to tilt the coin, you must tilt it independently of the mirror), but I noticed one thing that's worth mentioning. So I originally said that the mirror will give you a perfect white background that separates the coin from the background. Well, that is not entirely true. It turns out the mirror is just reflecting the light back from my custom flash adapter (3D printed in white plastic) that is mounted around the front of my lens, and it is this white light reflected off the flash adapter that gives the background a white appearance. So for anyone else not using a ring light, having a mirror as a background will probably result in a very dark background instead - though, still with good separation between coin and background for easy removal. Since my coin tilting device tilts both the coin and the background, I've had to forgo tilting my coins for photography when using the mirror background. This is a bit of a pain so I've again been looking at alternatives. Earlier in this thread I went through some tests where I tried illuminating the background independently, using very white backgrounds, or even using convex/dome shapes to help reduce any shadows and create more separation. I had a random idea to try retroreflective tape since the idea of a retroreflector is to direct light back to exactly where it came from. This might avoid the issue of white backgrounds creating a "halo" around the edges of the coin from stray/scattered light being reflected off the background at an angle. It also might help make the background brighter by maximising how much light is returned directly back towards the lens. Unfortunately, I didn't see much improvement with retroreflective tape over a normal white background, and even using a clear retroreflector disk for a bike didn't work that well either. The hunt continues.

Thanks for the shout out! Just want to mention that it should work in all modern browsers, I only tested it in Chrome, but theoretically Firefox, Safari, etc should be fine too. The main limitation for now is that it's not a good experience on mobile, though I'll hopefully fix this in the coming weeks/months.

I think most collectors probably do modulate their behaviour depending on the seller, it's just that there's relatively few black and white examples of good vs bad sellers that collectors don't often entirely stop buying from a particular seller, rather they factor it into their decision to bid. There's a number of auction houses and dealers where I wouldn't buy coin X for Y amount but I would from a more reputable auction house. If an auction house has a coin I really want and I can mitigate the risk through extra due diligence, then I'll probably bid on it. If they have a coin I only sort of want, or a coin I can't be confident in its authenticity, then I'd be more likely to skip it than if it were a more reputable auction house (or dealer). I'm sure there are some sellers that people here have decided to never buy from but perhaps that number would decrease in the hypothetical situation where the seller had a coin that this person really really wanted, it was priced very reasonably, and came with a fantastic provenance or other assurances that it were genuine (e.g. slabbed by NGC). So in instances like this I wouldn't close the door completely but they would otherwise fall into the group of sellers where I very much would prefer it if I never had a reason to buy from them.

That does make sense and I had thought this as well but we know from Sidon and Tyre that some of the dated issues have a surprisingly low number of dies. I think some of the early Sidon and Tyre "years" had only two or three obverse dies known to Newell. There's probably more but given the relatively few examples in PELLA and acsearch, I doubt there's more than a couple to be found unless a new hoard is uncovered. This is for Sidon and the first couple of "Dated" types are all like this, with only a couple of dies listed. The undated early types with the sigma control mark have more dies listed but given they're undated, they could theoretically span several years. It's not really until Year 13 (321 BC) that Newell lists more than 2 obverse dies for one of the dated types. Tyre (Ake) tends to have a few more dies for each type, but not a whole lot more. Between 333-330 BC, Newell lists a total of 11 obverse dies and some of the early dated issues (from 330 BC onwards) only have one or two obverse dies listed. Perhaps the bulk of the minting was being done back in Amphipolis at this time. Troxell lists 72 obverse dies for the Group A tetradrachms, which should all be fairly early in the overall sequence, either late 330s or early 320s.

Yeah I wouldn't be surprised if there are a few more dies here and there to add to what Newell had available. Though in terms of what is in ANS and acsearch, I didn't find much for Price 2990. I think I could match every ANS example of 2990 to one of the five dies in Newell, some of which are even the same specimen. There's only 5 or 6 examples in acsearch and while I didn't try die match those, on a quick glance they all seemed consistent with one of the five Newell dies. I think there's definitely contemporaneity to the striking of some of these types, as Newell even suggests in terms of the Officinas, but that doesn't mean there isn't a discernible order to the manufacture of the types. For example, you have the die links and die condition which help suggest an order to their manufacture. In the case of Price 2990 (Newell 1, "Officina A") and Price 2999 (Newell 2 "Officina B"), I don't think an order can be discerned and they would be considered equally contemporaneous. I believe the only reason Newell 1 comes first is because it makes more sense if it belongs to the "Officina A" line due to die linkage; similarly Newell 2 has closer die links with "Officina B", and on the assumption that A is earlier than B, Newell 1 comes "first" but for all intents and purposes they were probably produced at very nearly the same time. The other aspect that indicates an order to the die manufacturing, but not necessarily the coin striking, is the evolution of the symbols. For Tarsos it's a bit more confusing as you get the globule jumping around different positions of the field before suddenly turning into 4 globules. Damaskos is a bit easier as the globules do seem to increase in number over time. But you still might infer that the most sensical order of progression for Tarsos would be something like: no control marks --> globule or single letter --> letter + globule --> variations of letter + globule. Then the die links and die condition can help with the ambiguities, such as whether the lone globule came before the lone letter. Some of the dated issues of Sidon have only 1 or 2 known dies (to Newell) so I don't think we necessarily need to assume there was always a lot of dies, and therefore possibly different types, being struck simultaneously. So while Tarsos has a bunch of very similar early types with minor variations in control marks, Sidon and Tyre sort of demonstrate that these could have been spread out over a period of a few years. On the other hand, Damaskos Series II with the "Ram forepart" may have struck all its types over a period of only 1 or 2 years, so even though we know the order of the types it probably doesn't matter much numismatically because they were likely all struck within a short period of time. But speaking of die studies, I have thought about going through all the early types from Tarsos, Sidon, and Tyre to see if I can notice any new die links. Taylor has done something similar for Tyre and Sidon and found a new die link or two I believe. It's pretty tough given the condition of most of these early types though 😬

Nice one! I saw that went for a reasonable price, I may have gone for it myself but recently added to my collection the slightly earlier type (Price 2990 / Newell "Tarsos" 1) with the single globule above the throne strut. It's funny that this one comes before the type with no mint marks of any kind in both Price's and Newell's chronology. I believe it's due to the die-linkage pattern where Newell 1 (one globule) and Newell 2 (no mint marks) share some dies with each other, and thus are suspected to be contemporaries, but then separately share different dies with the "A" and "B" marked types respectively. Either way, all of these types are likely to have been produced fairly early in Tarsos' Alexandrine history. If you subscribe to the Tarsos "origin" hypothesis of Alexander's tetradrachms, then these would indeed be some of the very first Alexander tetradrachms ever produced, with 2990 being the first if the Price/Newell chronology is correct.

Gotta be this one for me

I've recently been working on a new "tool" for my website that leverages data from PELLA/American Numismatic Society to make it easier to explore the different mints that produced coins in the name of Alexander the Great. PELLA is a great tool itself and irreplaceable in many respects but there's a few things that could be done to make it easier to visualise the different mints, their relative locations and output, as well as similarities they may have in their production of Alexander types. Click on the following link or URL to view the "Coins of Alexander Map": https://artemis-collection.com/coins-of-alexander/map/ The "Mints" panel on the left side lists all mints in alphabetical order. If you use a filter, this list will exclude mints that don't match the filter conditions. Click on a mint in the list or on one of the blue mint markers on the map to view more details about that mint. The map shows all known mints that produced coins in the name of Alexander (and Philip III + Lysimachos types in Price) and provides a bunch of filters that you won't find in PELLA to help identify particularly interesting or unique mints. Filters like date of the appearance of "ΒΑΣΙΛΕΩΣ" at that mint, when the mint started/stopped production, how many unique types it was known to produce, and more. The size of the markers are in proportion to the number of total Alexander types produced at each mint. From the "Filters" panel, you can set your filters to narrow down the list of mints you want to view by their attributes. This will update both the "mint" list shown in the previous image, as well as the gallery of Price types below the map. You can also tilt the view of the map to see the topography of the landscape. See details on page for instructions. Clicking on either a mint from the side panel or a marker on the map will zoom you into that location and show you a summary of details about that mint. Below the map, every Price type belonging to a mint included in your search filters will be shown so you can get a quick look at the different types across the mints. Toggling the "Show only selected mints" button will limit these Price types to any mint you have clicked on in the map. Below the map you can see a list of individual types from the list of filtered mints. You can sort this list by a couple of different attributes like date and # of Coins for each type in PELLA. Enabling the toggle will further limit the types to any mint you have "active" in the left panel (i.e. showing the summary details) Some things to keep in mind: Desktop/laptop only for now. It will not look good on mobile, it will be practically unusable, and may not be suited for small screens like tablets (don't have one myself to test). This is one of several tools I have planned related to the PELLA database and is specifically aimed at exploring the mints of Alexander, not the types of coins themselves. So when you use the search filters, keep in mind you're filtering on the characteristics of the mints, not of the types within the mints. Another tool will be aimed at analysing the types in more detail. This tool is a work-in-progress and you may see it change or stop working briefly over the next week or so. If you have any comments/suggestions, feel free to share them below. I checked with ANS before using their data and images to make sure I'm complying with their non-commercial use terms. Many of the types with only one or two coins in PELLA have no images in my tool because those images come from other collections and I need to check the terms of each collection before incorporating them into this. So far I have only been able to test this in Chrome on Windows and Mac. It's possible you may experience bugs if using another browser, or possibly even the same browser. Please feel free to let me know if you notice anything that looks like it's not working correctly 🙂 Thanks!

@YOTHR are you no longer on Vcoins? I see you've popped up on MA-Shops though, I'm guess they have a better fee structure or something?

It's possible but difficult if there's any shadows or light gradient on the background. It's easiest when using a black felt background and a ring light since you don't have any coin shadow or light gradient from off-axis light, and the black felt absorbs most ambient light and should be pretty dark / nearly black if the photo is correctly exposed. For example, this is an unedited photo of a coin on a black felt background with a ring light providing the primary illumination. You could easily combine it with the reverse photo without any blending of the "seams". It's much harder to do with a white background (very hard to make a white background appear as solid white), as well as a grey background, for the same reasons. If you have perfectly consistent lighting and the background is not too textured, you can probably do it though. The downside is you can't reposition the lights for the reverse side compared to the obverse and IMO that's a big drawback since I often reposition lights for each side, particularly when the obverse is a high-relief portrait and the reverse might be more concave with less relief.

I don't wear glasses myself and have struggled with this! It can definitely be hard to tell just by looking at the camera screen. I have three things to help: 1. I bought a 7" camera monitor to plug into my camera. 2. I use the "focus peaking" setting on my camera which highlights in red the parts of the image that is in-focus in the live view. 3. I use "focus assist" which is a setting on Sony cameras that lets you zoom in digitally on the live view so you can check you have the focus right. Not all cameras have #2 and #3 but worth checking just in case. I searched the manual for your camera and it seems it may have focus peaking but perhaps only in manual focus mode. I use MF myself but can understand if others prefer auto focus. Perhaps the "Magnify" option mentioned in the manual is equivalent to Sony's "focus assist" too.

Speaking of which, I had this same problem recently as my Godox AD100 flash that I use as a fill light has a notorious green-tint to it that makes life difficult when you combine it with another light source (in my case, Godox TT350 flashes). In case anyone is interested, what I ended up doing is buying a Lee LED correction pack that comes with several filters to adjust the colour of LEDs in three ways: cooler, warmer, or less green. I guess LEDs tend to be too green rather than too purple, hence the lack of a "minus purple" filter. I found the 804 filter worked best and it brought the AD100 much closer to the TT350 in temperature. I cut out a disk from the 804 filter and put it inside the diffusion glass of the flash so from the outside you can't even tell I've done anything to it. The pack is expensive but I couldn't find the 804 or 803 available in the EU as a single sheet, where it should only cost a few euro. It seems only stage/production companies stocked it and would only sell to other companies. In the UK I found a few stores that sell to individuals but after factoring in import VAT and shipping, it made more sense to buy this big pack which I can then use to correct other LEDs. And on the topic of Lee filters/gels, I can recommend buying their diffusion gels as they're super cheap and way better than messing about with baking paper or tracing paper. Not only are they very resilient to tearing/wear but they're also going to be better colour-corrected than baking/tracing paper. I've bought their 216 and 250 white diffusion gels and can recommend those.

I bought this one and it's the one I used in the guide on my website but it broke fairly quickly. It's still useable, the "head" that holds the LED just came loose from the gooseneck and I had to fix it with some epoxy. That's just the ring light I used for the guide though, for my normal photos I have a 3D printed ring light that attaches to my flash heads. I can't recall exactly how long the Amazon right light is but it was a good length, probably about 40cm or so. The diameter of the ring light itself is about as wide as you would want to go too. A lot of the other ones on Amazon are more for videography and have massive ring lights that wouldn't work well for coins. The lack of sharpness and the noise is probably mostly due to the issues I mentioned earlier about cramming 108 MP into a sensor the size of a fingernail. It boils down to the adage that "megapixels aren't everything" and this camera phone is really the perfect example of that. What matters more than the number of pixels is the sensor itself, not only the size of the pixels but also how much information can be captured by each pixel. So when you have very tiny pixels in a relatively tiny sensor, the camera's ability to resolve detail diminishes, as does its ability to capture a lot of light and dynamic range (hence the noise). So RAW mode or not, or Pro mode or not, the limitation is going to be the sensor and for coin photography it probably won't be any better than a standard camera phone.

By "stain" are you referring to the part circled red in the image below? If so, I don't think it's a stain, or there may be a mark there on the coin but the dark spot itself is predominantly caused by the lighting. I've circled in orange other parts of the coin on both sides that have the same problem I mentioned earlier. I used to get it a lot in my photos but I've gotten better at combatting it, still you can see hints of it in some like the second photo below showing the slightly darker flat areas circled in red. It may be that everything you've tried doesn't help improve it as I think it's largely to do with the LED ring itself and either the distance or diameter would need to be changed to help lessen it. Possibly tilting the coin would help, or you can add some white paper close to the coin to reflect some more light from the LED ring onto the coin from an angle.

On this note I've been curious about Reflectance Transformation Imaging as a tool for this purpose, though hesitant to get involved since it would be quite a significant project. Essentially, it would let you experiment with different lighting conditions virtually but you are still somewhat limited to the lighting setup inside the dome - you can only turns on or off individual lights. Though looking at it again, it seems making one on a smaller scale that would suit coins could be feasible: https://petapixel.com/2016/04/21/shoot-super-detailed-macro-photographs-rti-camera-rig/ One thing these RTI setups can't do, as far as I'm aware, is allow for adjustable distances between the subject and lights. I made this GIF for one of the articles on my website which illustrates how important light-subject distance can be for ring lights: