Share your Coin Photography Tips & Tricks!

[Nerosmyfavorite68]

Thanks for the tip. 

[Kaleun96]

30 minutes ago, Nerosmyfavorite68 said:

I'm going to have to do a deep dive this weekend and soak up all the information here; there's a lot of great tips!

I'd sure love to see a post-photography thread as well.  What to do after the coin's been photographed.  I.e. tricks for photoshop/paint shop pro/etc. novices. One could have a fantastic raw photo, but not know what to do with it afterwards.  I have problems separating the image from the background.

I wonder if the Note 20 has a macro lens?  I could do the book setup..

Yeah good idea, a post-processing thread would be helpful. That's definitely my least preferred part of the process and the part I'm worst at!

[Severus Alexander]

7 hours ago, Kaleun96 said:

Your example might be possible if we're talking about taking two images from the setup I used for the USAG testing and then edited the photos so that they were both 1200x1200px, but I don't think this is what you intended. Let me know if it was though!

Yeah, this is what I meant. (Same as what you describe at the end of your comment.) I was imagining someone posting coins online at a maximum of 1200px (appropriate here on Numisforums, or for a dealer on VCoins for example), and asking myself if they’d benefit from having a full frame camera over an APS-C. It seems the answer is that the benefit is likely minimal, and mainly for very small coins like hemiobols and tetartemoria. But if you want a larger image than that for print, enlargements, or for zooming in, the full frame would be beneficial.

Of course that’s a bit rough, as the point at which it makes a visual difference is hard to guesstimate, and there’s the black box factor of digital image processing too (whereby resolution can be boosted by taking advantage of regularities across images).  Probably the only way to be sure you’d get a benefit at your target image size would be to test out the two competing setups. 

[Kaleun96]

41 minutes ago, Severus Alexander said:

Yeah, this is what I meant. (Same as what you describe at the end of your comment.) I was imagining someone posting coins online at a maximum of 1200px (appropriate here on Numisforums, or for a dealer on VCoins for example), and asking myself if they’d benefit from having a full frame camera over an APS-C. It seems the answer is that the benefit is likely minimal, and mainly for very small coins like hemiobols and tetartemoria. But if you want a larger image than that for print, enlargements, or for zooming in, the full frame would be beneficial.

Of course that’s a bit rough, as the point at which it makes a visual difference is hard to guesstimate, and there’s the black box factor of digital image processing too (whereby resolution can be boosted by taking advantage of regularities across images).  Probably the only way to be sure you’d get a benefit at your target image size would be to test out the two competing setups. 

Ah I see! I think I got confused because you mentioned the 20um pixel size so thought you were talking about another hypothetical camera. Pixel size for an image file on your computer is really only relevant for prints these days in terms of things like pixels per inch (e.g. 20um would be 25.4/0.02 = 1270 PPI). For uploading to the internet and viewing digitally I don't believe DPI/PPI matters, the pixel size will be dependent on the screen used to view it.

But going back to your hypothetical, I could simply resize the USAF test I did earlier so that a portion of the chart from the FF example is scaled down to be the same size, and covering the same field of view, as the APS-C example.

That way, we're reducing the number of pixels used to capture the detail of the FF photo so that it is the same as the number of pixels representing the same area in the APS-C example. What we find is close to what I hypothesised might happen in my previous post. The amount of detail resolvable is about the same, I think, but the FF image is sharper and seems to have less chromatic aberration. The FF image is also at a bit of a disadvantage since it has been compressed and that probably can introduce some image artefacts.

APS-C (original size 781x628px)

Full Frame (scaled down to 781x626px)

 

And here's a closer view of the middle section with APS-C and Full Frame side-by-side.

 

As you say though, if you're only ever going to view the photos at 1200px then upgrading to full frame is probably not worth while. Though I do think an image size of 1200px is perhaps a relic of 10-15 years ago and these days most websites should be supporting nearly double that at the very least. There may also be cases where you can only upload an image at 1200px but you want to highlight a particular part of the coin so you zoom in on the coin and then crop that to 1200px. That's a use case more similar to my previous test where you are taking advantage of the increased resolution of the full frame image and you end up with a fairly noticeable difference compared with the APS-C image.

[Randygeki]

[Severus Alexander]

2 hours ago, Kaleun96 said:

Ah I see! I think I got confused because you mentioned the 20um pixel size so thought you were talking about another hypothetical camera.

Probably everything I say is confusing because I'm not fluent in camera-speak. 🙂 When I was talking about a 20 micron pixel size, what I meant was that 1 pixel in the 1200px image corresponded to approximately(?) 20 microns on the coin.

Maybe the most useful thing I can do is to actually show what sort of resolution I can get with my setup, using my old 20 MP Canon EOS 70D with a 25mm extension tube and an 18-50mm zoom lens.  Here are the details for its CMOS sensor:

The rest of these pics are screenshots of what I see on my Mac's screen (16 inch laptop with a 3072 x 1920 resolution; the screenshots are compressed using jpg so not exactly what I see but pretty close if you click to view them at full size on a similar size/resolution screen).  Here's a screenshot of the original raw image. As you can see I didn't put much effort into making sure the coin, which is 20mm, took up the whole field, so I haven't maxed out my resolution:

Now, zooming in to the central circle, which is 10mm:

On my screen the above image still shows good detail.  Now zooming in further:

^ Here I just start to notice some detail blur, although if I use Canon's DPP4 software and change the image mode to "fine detail" that improves quite a bit.

^ Definitely getting some blur here, although I can't see individual pixels.

^ Now I see pixellation.

Since this sort of resolution is fine for my purposes - I don't print out the images, I rarely need closeups, and I can get pretty much any size coin to fill the frame - upgrading to a full frame camera, or even a newer camera with better lenses, isn't worth the expense.

2 hours ago, Kaleun96 said:

And here's a closer view of the middle section with APS-C and Full Frame side-by-side.

This does a good job of showing the advantage of FF for blown up images.

2 hours ago, Kaleun96 said:

As you say though, if you're only ever going to view the photos at 1200px then upgrading to full frame is probably not worth while. Though I do think an image size of 1200px is perhaps a relic of 10-15 years ago and these days most websites should be supporting nearly double that at the very least. There may also be cases where you can only upload an image at 1200px but you want to highlight a particular part of the coin so you zoom in on the coin and then crop that to 1200px. That's a use case more similar to my previous test where you are taking advantage of the increased resolution of the full frame image and you end up with a fairly noticeable difference compared with the APS-C image.

Agreed on all points!  Thanks for your help navigating these technicalities, @Kaleun96, I hope it has proven helpful for others too.

Edited August 24, 2022 by Severus Alexander

[Kaleun96]

15 minutes ago, Severus Alexander said:

Probably everything I say is confusing because I'm not fluent in camera-speak. 🙂 When I was talking about a 20 micron pixel size, what I meant was that 1 pixel in the 1200px image corresponded to approximately(?) 20 microns on the coin.

Maybe the most useful thing I can do is to actually show what sort of resolution I can get with my setup, using my old 20 MP Canon EOS 70D with a 25mm extension tube and an 18-50mm zoom lens.  Here are the details for its CMOS sensor:

The rest of these pics are screenshots of what I see on my Mac's screen (16 inch laptop with a 3072 x 1920 resolution; the screenshots are compressed using jpg so not exactly what I see but pretty close if you click to view them at full size on a similar size/resolution screen).  Here's a screenshot of the original raw image. As you can see I didn't put much effort into making sure the coin, which is 20mm, took up the whole field, so I haven't maxed out my resolution:

Agreed on all points!  Thanks for your help navigating these technicalities, @Kaleun96, I hope it has proven helpful for others too.

Nice photo! Definitely seems you're not wanting for resolution with that setup.

Thanks for the questions and hypotheticals, it's been fun refreshing my memory on this stuff and breaking out the USAF resolution chart, which I have done exceedingly rarely 😅

[Prieure de Sion]

Allow me to ask you a question - not directly about photography, but rather about image processing. Are any of you familiar with Lightroom?

When I was optimising my setup, I noticed that my current image processing software also needs improvement. With the previously free software, I cropped, post-processed and composited the coin images. But the result from the raw material is not optimal. 

So today I accepted an offer from Adobe and took a package of Photoshop, the new Lightroom and Lightroom Classic and started experimenting. I can already manage the post-processing of the images very well. 

But what I somehow didn't find or don't understand - how do I release pictures? I have pictures of my coins with a white or black background. In my free tool, I could simply click on the background in a special menu and it was gone - and the coin was cropped. 

I didn't find that in Lightroom.
But Lightroom can do that, can't it?

[Kaleun96]

8 hours ago, Prieure de Sion said:

Allow me to ask you a question - not directly about photography, but rather about image processing. Are any of you familiar with Lightroom?

When I was optimising my setup, I noticed that my current image processing software also needs improvement. With the previously free software, I cropped, post-processed and composited the coin images. But the result from the raw material is not optimal. 

So today I accepted an offer from Adobe and took a package of Photoshop, the new Lightroom and Lightroom Classic and started experimenting. I can already manage the post-processing of the images very well. 

But what I somehow didn't find or don't understand - how do I release pictures? I have pictures of my coins with a white or black background. In my free tool, I could simply click on the background in a special menu and it was gone - and the coin was cropped. 

I didn't find that in Lightroom.
But Lightroom can do that, can't it?

Lightroom is a bit weird in that it overlaps a lot with Photoshop but still needs to be used in-conjunction with it. Lightroom is best when it comes to modifying how the image looks without adding/removing pixels, e.g. correcting the colour, orientation, lens distortion, etc. Photoshop is better when it comes to adding/removing things, like using the select tool to remove the background or clone stamp to remove dust.

So generally for background removal you will want to do that in Photoshop. It has several tools that can help but the easiest to use is the "Remove Background" tool under Quick Actions. Photoshop will have a bunch more tools to help refine that process if it isn't able to separate the background neatly.

Lightroom can be used if you just want to paint your background a solid colour but it really only works if you want the background to be white or black. It's an option if you're not saving your photos as transparent PNGs (i.e. with no background). I used to do this before doing full background removal. I would shoot the coin on a black background and then just use Lightroom's masking tool to make the background solid black.

Edited August 25, 2022 by Kaleun96

[Prieure de Sion]

25 minutes ago, Kaleun96 said:

Lightroom is a bit weird in that it overlaps a lot with Photoshop but still needs to be used in-conjunction with it. Lightroom is best when it comes to modifying how the image looks without adding/removing pixels, e.g. correcting the colour, orientation, lens distortion, etc. Photoshop is better when it comes to adding/removing things, like using the select tool to remove the background or clone stamp to remove dust.

So generally for background removal you will want to do that in Photoshop. It has several tools that can help but the easiest to use is the "Remove Background" tool under Quick Actions. Photoshop will have a bunch more tools to help refine that process if it isn't able to separate the background neatly.

Ah ok - i understand - so first I will modify and optimize my pictures with Lightroom - and if I will be finished, then I will work with photoshop clear the background, add the obverse and reverse to a new background mask etc..

Thats no problem - because the package I get includes Lightroom and Photoshop.
I have booth apps.

Edited August 25, 2022 by Prieure de Sion

[Etcherdude]

My advice is to focus your attention on learning Photoshop. Though you can use it for editing, Lightroom is built for processing and organizing large collections of images.

[Nerosmyfavorite68]

I have the hard copy of the Photoshop Creative Suite CS5, which has Photoshop, but no Lightroom, infuriatingly.  Not that I'm an expert at either. I've never used Lightroom. I like the modern Audition (although, infuriatingly, I have to use 1.5 to do basic things like variable time correction or insert silence).  The rental on Photoshop is just WAY too much for what I use it for.

I also have a pretty up to date Paint Shop Pro, and although I never use it, GIMP.

I have some experience with workingwith RAWs.

Randygeki's setup is something I can build, but the camera setup is left out.  I actually have a pretty ready made workspace, with that 1940 Philco chairside. It was built to be a side table.

And per an earlier Rube Goldberg reference...

[Kaleun96]

1 hour ago, Etcherdude said:

Though you can use it for editing, Lightroom is built for processing and organizing large collections of images.

Just to clarify, Lightroom isn't only for when you need to process a large collection of images. It's meant for processing individual images too and is a key step in many photographers edit process before moving on to Photoshop.

But for many of us here, whether it's worth learning Lightroom depends on your needs. If you just want to tweak the brightness, contrast, and exposure, with a quick colour correction to finish up, then Photoshop is fine. If you want to play around a bit more and really dial in the settings for how the coin appears, you can't beat using Lightroom and Photoshop.

I find the masking tools in Lightroom to be really useful compared to Photoshop for when you need to clean up the edges for background removal, or make some tweaks to areas where some light has reflected a particular colour onto the coin, or where part of the coin is darker/brighter than you would like and you want to balance it out with the rest of the coin etc.

I basically only use Photoshop for removing the background, rotating the coins, placing them side-by-side, and exporting the final images. Though others here that have more complicated compositions (e.g. drop shadows or directional lighting effects) will probably spend more time in PS than Lightroom.

[Prieure de Sion]

I'm nowhere near my goal! I'm still waiting for the Olympus macro lens. So I experimented a bit today - with your mentioned lighting tips - backgrounds and working a bit with Photoshop and Lightroom. 

The only camera I have is my iPhone - unfortunately it doesn't have a macro lens and since it's not a 13 - it doesn't have a macro function either. So I had to take all the pictures with a mobile phone without macro. You notice - because I had to zoom in on the objects (3x zoom) - that the coin images are very grainy / blurred. As soon as you have to zoom in electronically - the mobile phone pictures quickly fade and get a high level of noise.

But today it was all about trying out your tips on lighting and background. There is still a lot of room for improvement. But probably photography is also a lot of trying out and experimenting. I still have to practise a lot. I'm looking forward to my macro lens for my camera arriving next week.

 

 

Edited August 27, 2022 by Prieure de Sion

[Nerosmyfavorite68]

At some point this weekend, I'll try the book and the Note 20.  Can't hurt.

 

[Nerosmyfavorite68]

Tomorrow morning will probably be a good time to try the Note 20 way, using a book (or two). Does one have to turn on the flash for that method? 

I've been learning a bit about pro mode from this video.  Pro allows me to save in RAW, and to have more customization.  However, the images are smaller, I think only 14 mp.  I think it forces one to use jpg if one uses 108 mp.

If I try manual; i.e. if auto doesn't have good results, what kind of ISO and shutter speed should I try?

I guess 14 would be good enough for a coin. It would also give me more options, with RAW.  The raw is .dng, thank goodness.  The raw on my Sony is ARW.  There's a converter, but it's a PITA.  My old version of Photoshop doesn't open ARW, although Paint Shop Pro does.

Edited August 27, 2022 by Nerosmyfavorite68

[Kaleun96]

22 hours ago, Prieure de Sion said:

I'm nowhere near my goal! I'm still waiting for the Olympus macro lens. So I experimented a bit today - with your mentioned lighting tips - backgrounds and working a bit with Photoshop and Lightroom. 

The only camera I have is my iPhone - unfortunately it doesn't have a macro lens and since it's not a 13 - it doesn't have a macro function either. So I had to take all the pictures with a mobile phone without macro. You notice - because I had to zoom in on the objects (3x zoom) - that the coin images are very grainy / blurred. As soon as you have to zoom in electronically - the mobile phone pictures quickly fade and get a high level of noise.

But today it was all about trying out your tips on lighting and background. There is still a lot of room for improvement. But probably photography is also a lot of trying out and experimenting. I still have to practise a lot. I'm looking forward to my macro lens for my camera arriving next week.

 

 

Looking good! Love the toning on the third coin from the top. I've noticed with my Samsung that zooming in often makes it worse than taking a photo zoomed out and then cropping it. As you say, the digital zoom creates a lot of noise. You'll also have to watch out for the phone changing lens when you zoom, e.g. it may change from wide-angle to standard and then to telephoto. These different lenses will probably have different depths of field and apertures so you may find some work better than others.

[Kaleun96]

12 hours ago, Nerosmyfavorite68 said:

Tomorrow morning will probably be a good time to try the Note 20 way, using a book (or two). Does one have to turn on the flash for that method? 

I've been learning a bit about pro mode from this video.  Pro allows me to save in RAW, and to have more customization.  However, the images are smaller, I think only 14 mp.  I think it forces one to use jpg if one uses 108 mp.

If I try manual; i.e. if auto doesn't have good results, what kind of ISO and shutter speed should I try?

I guess 14 would be good enough for a coin. It would also give me more options, with RAW.  The raw is .dng, thank goodness.  The raw on my Sony is ARW.  There's a converter, but it's a PITA.  My old version of Photoshop doesn't open ARW, although Paint Shop Pro does.

I have written a little bit on some settings you can try here under "Camera Settings" but it will mostly depend on your lighting setup. In general, I would aim for a shutter speed no "slower" than 1/60s, ideally something around 1/120s to 1/90s. If you're using LED lighting, you may find faster shutter speeds (e.g. 1/180s) are fast enough to capture the flicker of the LED and will cause vertical lines to appear in the photo. If this doesn't happen, feel free to use even faster shutter speeds if necessary.

The other setting to balance is the ISO. You want this to be as low as possible but without a lot of light this would be difficult. Ideally something in the range of 100-400 should be fine. If you find it's too dark, you may need to decrease your shutter speed. But if your ISO is set to 800 and your shutter speed to 1/60s, I would take that as an indication that you need more light. If you can manage ISO 400 at 1/90s shutter speed, that's probably adequate.

If you have an option to change the light metering mode, you want something that focuses on the centre of the image. If there's an option for "spot" metering, use that and ensure the spot is over the centre of the coin. Otherwise, "center-weight" metering is probably the next best. Essentially, you want the phone to ignore trying to expose for the background - we only want to worry about the exposure of the coin.

[Nerosmyfavorite68]

Thanks for the excellent tips!

[Nerosmyfavorite68]

When I use my Sony alpha 77 to do record labels, I'm forced to use Multiframe noise reduction mode.  Works well ehough, but it only allows jpg.  I suppose I might as well just try with my 108MP smartphone.

Random label.  This one is a decayed peeler :(    Too bad, it's a great episode.  

My labels never had to be artistic masterpieces; they're for research.  I just have to make it so it looks halfway decent; usually through brightening.   I'm going to have to revamp my photo area for coins.

 

[Nerosmyfavorite68]

Hmm, I guess I could look in the hardware store for dowels.  There might be something that will make a decent riser in the garage.

[Kaleun96]

12 minutes ago, Nerosmyfavorite68 said:

Hmm, I guess I could look in the hardware store for dowels.  There might be something that will make a decent riser in the garage.

For large-ish coins, bottle caps can work in a pinch. For smaller coins, you can use a 1/4" nut or two stacked together, though it's best to have some putty or blu tac so the coin isn't resting directly on the metal and won't slide around at the slightest bump. If you happen to have an o-ring of similar size laying about in the garage, that can work instead of putty as well.

[Nerosmyfavorite68]

I found the camera tripod; it's actually a pretty nice one, and has a wide range of heights. However, I wasn't able to lock the camera into pointing straight down, no matter how hard I tightened the screw.

But even if I did, that begets the condundrum; how to put the coin directly underneath?

I found some handi-wipes, made a cutout for the CD spindle, and experimented.  It looked somewhat ok on the phone's preview, but I'll have to see.

[Nerosmyfavorite68]

I think we might have to settle for the Note 20 method. The camera setup is just too daunting, the results too frustrating, and I don't want to spend hundreds for something which I won't do very often.

[Kaleun96]

18 hours ago, Nerosmyfavorite68 said:

I found the camera tripod; it's actually a pretty nice one, and has a wide range of heights. However, I wasn't able to lock the camera into pointing straight down, no matter how hard I tightened the screw.

But even if I did, that begets the condundrum; how to put the coin directly underneath?

I found some handi-wipes, made a cutout for the CD spindle, and experimented.  It looked somewhat ok on the phone's preview, but I'll have to see.

Do you know the make/model of your tripod? Most with a ball head mount should allow the camera to be pointed directly down, the more common issues are whether the tripod can support the weight without tipping over and keeping the legs out of the way.

On the "side" of the tripod you point the camera down over, you need to have the two legs of the tripod on this side otherwise if you have the "third" leg of the tripod on this side, it will be in the way of the camera. But by having the two legs on this side, there's very little support to stop the tripod tipping over so you may need to add a counterweight to the third leg behind the camera like this:

But this of course takes up a lot of room. If you don't extend the legs out so far, so the footprint of the tripod is smaller, you need more counterweight to stop it from tipping over. Some smaller tripods can work without a counterweight if the camera is able to rotate further than 90 degrees to face down. Then, you setup the tripod so the two "front" legs are longer than the back leg, forcing the tripod to lean backwards, and then you rotate the ball head past 90 degrees facing down so the camera is perpendicular to the surface. If your ball head can't go further than 90 degrees past horizontal, then this method doesn't work as your camera will be on an angle relative to the surface.