Testing out new macro lens & looking for feedback

I just got an 100mm macro lens for my DSLR (previously using an 135mm zoom lens), and am trying to get the hang of it. Ancient coins pose a particular challenge as many of them have uneven planchets or are high relief, which is making it difficult for me to avoid out-of-focus areas on the coin. Here are a few examples:

I had to tilt this coin into the light slightly to bring out the toning, which made it tough to get the inscription in focus while also keeping the portrait in focus.



The portrait here is extremely high relief, also making it difficult to keep the portrait and the inscriptions in focus at the same time.



Do I need to mess around with the aperture settings to get the entire coin into better focus? I'm used to just using the default macro setting on the camera, so don't have any experience with that. Or could moving the camera further away from the coin and zooming in more help out at all?

I'm also using a tripod instead of a copy stand, which makes manual focus a little more difficult - I'll be buying a focus rail which should hopefully help out a little bit.

 

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The pics look great to me.

 

I'd agree! Stunning!

 

The pics look great, but to answer your aperture question, yes - a higher aperture number will get more of the coin in focus, but you'll also need a slower shutter speed to compensate for the darker image. Set a higher aperture number (like f11), and then adjust the shutter speed until the image is the brightness you want, and then use the camera's timer to take the shot so you aren't manually pressing the shutter and shaking the camera.

Use the 100mm prime lens instead of the zoom lens - it was made for macro.

 

Your photos look crystal clear and sharp to me. Great job, @Volante ! Welcome back to the Ancients Forum!

 

Great looking photos!

What lighting set up are you using?

John

 

Yes great photos... I am also interested in the rest of your set up.

 

The photos are great but you can use a small aperture to increase depth of field as mentioned by others above. There is a problem with overall sharpness limitation by diffraction when you stop down too far so it is bad to shoot everything at f/16-22 unless needed. The other answer is to use photo stacking software where you take several shots each focused on a different plane and let the software combine them into one using the sharpest part of each. For coins, three input images may be enough but I have shot flowers using ten and microscope workers use many more. This allows tilting and dealing with high relief coins.
Samples:


I use a freeware program called CombineZ but there are many others I have not tried. I do not collect software and CombinesZ has been all I need.
https://en.wikipedia.org/wiki/CombineZ

I first used it for flowers.

 

I agree with @dougsmit . I prefer stacking to stopping down because when I stop down I usually have to increase ISO sensitivity which results in photos that are not as sharp.

Like others, I am also interested in your lighting set up? Do you use any kind of special bulbs?

 

Thanks for the info! I'll test out a higher aperture number and see how that goes. I've heard of focus stacking for landscape shots, so makes sense that it would work for macro photography as well - will give that a shot as well.

As for my setup, I've got 2x gooseneck desk lamps with natural daylight CFL bulbs at the 10 and 2'o clock of the camera, though I often use just one lamp on smaller coins. I have the camera in a cheap tripod from Amazon, with the bulbs at approximately the same height and as close to the camera as possible. I'm currently putting the coins on top of a Trader Joe's pepper grinder (as professionals do) to get them closer to the lens. I'll stick a flip under the bottom of the grinder if I want to angle the coin into the light to bring out luster or toning.

EDIT - the pepper grinder is actually from Costco, not Trader Joe's. Apologies for the confusion

 

Fun isn't it? I use a Canon camera 70D and was happy to acquire a 60mm lens fifteen minutes it was posted on Craig's List. I love it. You are absolutely correct regarding ancients, they are indeed challenging especially high relief items such as some Alexandrian tets. Works on scyphates as well. Have fun with playing around.

I have found a simple means of working with them. I use a very cheap set of sockets found at a discount hardware outlet. As you may know, they come in different diameters and have large openings to fit the nut or bolt size. I then put Gorilla Tape on the opening, trim it so only the rim of the socket is covered with the tape which protects the surface of the coin you are wanting to photo. It's such a simple solution as you have the obverse image in the hole, so no leaning of the coin. Sorry, but I don't have a photo of one.

 

And here I was halfway out the door to Trader Joe's for a pepper grinder...

 

Dougsmit’s answer is the best. Creat a stack of images in slightly different focus. It’s easy to do in Photoshop. I’ve shot VERY high relief medals with great results using that technique. I usually take 6-8 images and stack them.

 

The OP photos are incredible.

 

I find a good coin support can be made from a used up ball point pen of the type sold at Costco in huge packs with rubber grips to soften the blow on your fingers. Unscrew the front part and pull the rubber/silicone soft part over the end so there is no hard plastic showing. The hollow tube created allows some tilting of curved surface coins and protection without Gorilla tape. I do own some black Gorilla tape, who doesn't? I place this modified pen over a right-sized dowel (third from left below) raising the coin to the height I wish. It is the second from the left in the photo below. On the left is a smaller one for obols made from other pen parts. Far right is one for larger coins made from a plunger from a disposable syringe. Not shown is a hollow tube top that places a dark hole in the center for shooting Chinese cash.

BTW: I use a Canon 100mm macro which is equivalent to the 65mm mentioned above when used on my full frame Canon 5DmkII. While it is a great lens, a lot of the advantage of the macros is in flat field edge sharpness that makes a lot more difference for most macro subjects that for round coins that do not fill the corners of the frame. Images with either the 70D and 65mm or the 5D and 100mm are plenty good enough to make the 20x30" prints Costco sells. My local Costco does great print work.

 

Great Idea about Costco, I'll have to try that. Cheers

PS.(does anyone use that anymore?) I'll take some pics of the socket this weekend and will post later.

Hey Doug, do you fill your frame with the coins you shoot?

 

Only sometimes. I am often lazy and shoot #2 at the same crop that I shot #1 on the theory that the camera is so much overkill that I can be sloppy. The quality difference of a full frame camera is considerable. Shooting loosely also lets you stay farther back allowing more flexibility in lighting. I try to keep at least 6 inches back from the coin. When shooting small, small coins I have switched to a longer lens but the fact is most of my really tiny coins are not high enough grade to benefit from all those pixels.

 

It looks like you're off to a great start!

I find that with a pair of daylight bulbs like you're using I can stop down to f/11, sometimes f/16, and still have reasonable exposure lengths with ISO 400-800 or so, I think. But you will want to use either a remote shutter release or a delay setting so you don't leave the camera vibrating when you press the shutter.

Also, especially if you're using a cheap (as in "less than $300") tripod, you'll want to consider using your camera's Mirror Lock-Up feature. That will eliminate one more source of vibration.

Once you have vibration under control, you can use whatever exposure length you want -- if you want to shoot ISO 100 at F/16 with ambient light, just leave the shutter open for however long the camera thinks it needs, even if that's several seconds.