Focusing on a flat table.

I took dougs advice on coin photography, and it seems to be working for the most part.

However, when I lay a coin flat on a table, it will not focus clearly. Even when I manually focus it.

As you can see by these images on the front, the outer areas of the coin is somewhat in focus, but the center is not, it's the opposite on the reverse.

 

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Tim? It's looking good from where I'm sitting.......

[loving the new avatar]

 

Its a smidgen blurry to me.

 

I think it's camera movement.

 

OK, maybe it's the bourbon, but I ain't seeing any 'shakiness'.

I would like larger pics, though.........

 

Are you using a timer or remote shutter?

 

I have a remote, I don't have a copy stand or tripod.

 

Thanks Tim.......Just a trifle out of focus, but overall, very nice.....

 

I think it might be something in my camera optics. I can focus so-so when the coin is at an angle. But laying on the coin on a flat surface is a whole different story.

All I can think of is that the auto-focus is focusing on the surface the coin is laying on, but I do point the crosshairs on the center of the coin. Manually focusing does not help either.

 

Detecto, it is similar to target shooting. Study camera and slow squeeze of the shutter button.

Estimate how high the camera is for most shots using the macro setting, and then find something of the same height to use to support your hands and thus the camera at the same height. I find that the plastic cover from a 100 CD stack/spindle (about 6" tall makes a good support for a handheld camera shooting coins ( your height may vary ) and since it is clear, light isn't blocked much by it. Support the camera in both hands resting on the support, focus and then take a breath and exhale it and don't breathe until you slowly squeeze the shutter button. It is fast movement on the shutter that often cause problems. After the camera fires, don't forget to breathe . This will help until you get something to fasten the camera in a position so you don't have to hold it in your hands. Copy stands are often available on ebay or craigslist, as more use scanners these days. Best of luck.
Jim

 

The cheapest copy stand I can find right now is $50. Which I think is rather high. All it is, is a board, a piece of metal that telescopes, and a screw for the camera.

The last one in auction, which was used, and kind of rough, sold for exactly the price of new. Go figure.

 

also, does your camera have "modes" where there are different focusing modes? If so you may want to try a different mode that does not pick up the surrounding table.
Also, another trick, set the coin up on something a couple of inches above the table. That may take the focus off the table and center it on the coin.

 

I have a salvaged enlarger that I occasionally use as well as an old drill press. Both work fine.

Check out garage sales or craigslist for copy stands.

 

This one is nice for the price (28.50). May not work if you buy a long macro lens.
http://www.bhphotovideo.com/c/product/686877-REG/Dot_Line_RS_CS305_9_x_12_Desktop.html

 

I think you need to stop down your lens, down to f/11, to increase your depth of field. f/5.6 at 55mm and a few inches working distance has a very small DoF and any movement at all (such as pressing the shutter release button) can move the camera out of focus. Going to f/11 will help, but you really need a tripod/copystand/whatever. Some DIY stuff here:

http://www.coincommunity.com/forum/topic.asp?ARCHIVE=true&TOPIC_ID=19857

Also remember, a lens that isn't designed to do macro photography (which is always trying to fit things into the razor thin DoF), will have a curved focal plane - especially an inexpensive kit lens.

If I were trying to get something going on a budget, I'd be making a DIY copy stand and looking for a used manual-focus only macro lens in the 50-100mm range. It should be easy to find something reasonably priced, especially for nikon.

 

Here's a copystand for a small camera.

$39
http://www.bugeyedigital.com/product_main/dig-dpcs129.html



$28
http://www.adorama.com/CECS305.html

 

I would go along with Doug's suggestion about the tabletop tripod. I used a regular tripod for years (placed at the corner of a table) and never had a problem with focus.

If you're still considering a copy stand, I only have one piece of advice. An inexpensive copy stand is just that for one reason.........because it is cheaply made. Try to avoid ones with plastic gears. They don't hold up well.

Chris