Yes, if you look here:
http://d3d71ba2asa5oz.cloudfront.net/12014191/images/ua1175974a__1.jpg
You can see the silk screening, especially in the bottom left corner is really blurry and you just cant read it.
Hmmmm... Yeah, I see what you mean.
In looking at this shot quickly, I'm thinking it's just a poor shot (no offense). The fact is getting really, REALLY sharp shots,
consistently, is not as easy as some people think. What I mean to say is I think there are issues here with technique. This is not a depth of field issue or an issue with your current equipment. That being said, I think it could be motion blur, or mirror-slap, causing the blurriness in that particular shot. The fact that some of your other shots ARE as sharp as they are kind of confirms this in my mind. Your camera and lens are definitely capable of giving you what you want but I think there's some pilot error here. Again, no offense intended, I'm legitimately trying to help you get the very best shots you can...
In looking over you previous posts, I do notice the shutter speeds you're using tend to be a bit on the slow side. That's not a bad thing but it needs to be understood and dealt with. I'm assuming you're shooting these from a tripod, yes? If not you absolutely need to be.
Also, you might want to try using the camera's built-in self-timer to delay the shot by 5 seconds after you press the shutter button. This will kill 99% of motion-blur. That, or you could invest in one a cheap wireless shutter-release so you don't have to wait 5 seconds between shots. The Nikon-branded wireless releases are in the $25 range with decent third-party knock-offs running
$10 or so on Amazon. Trying some shots using the self-timer would tell you if it's motion blur causing the issue before you go and invest $10 in a wireless release, though.
Okay, big edit...
I'm also wondering how you're taking the shots. Let me see if I can ask this coherently...
When you frame the shot of the board in the viewfinder, are you zooming in so the board fills the viewfinder? I ask because the lens you're using may be going "soft" in the corners and if that's the case then we need to know that. What you might try doing is taking the shot with the board centered in the frame but with lots of space around it; maybe fill *half* the frame with the subject as you see it in the viewfinder, the rest being empty space. This keeps your subject (and the silkscreening) away from the potentially soft corners of your frame. Take the shot as described and then, in Lightroom, zoom in and crop the shot before you do any other adjustments (to color, saturation, contrast, etc.) and check your corner sharpness.
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