I had to look this up, and am surprised to learn that you're right about having to declare these things... I never have.

Also found this interesting note on the US Customs website:

"For Customs purposes, clothing, jewelry, photography equipment, portable radios, and vehicles are considered personal effects and cannot be brought in duty-free as household effects. However, duty is usually waived on personal effects more than one year of age."

Since I have lived abroad since 2004, and acquired the majority of my photo equipment in China, Hong Kong, and Japan, this would apply to just about all my gear. Complicating things further, is that I've bought products FROM American retailers (KEH, UniquePhoto, etc) and had them shipped abroad!

I certainly don't plan to 'declare' my entire gear bag everytime I come home for the holidays when I bring my camera and kit. I don't even know how they could determine which items, where I bought them, and when I purchased them.

Wonder if I should just leave anything I've had less than a year in my apartment in Kiev when I come home for Thanksgiving...

... but I'll probably just take my chances.

Frankly, I think US Customs officials are more concerned with people bringing suitcases full of cheap smartphones, drugs, small children, etc than an odd lens or camera.
In the case of the OP - I'm not sure how US Customs could prove that you didn't have the camera with you when you left or that you purchased the item abroad (especially if you paid in cash).

Anyone on this thread ever had an issue with bringing photo gear through US Customs?

I have two NIkon Df bodies Both bought used with very low shutter counts. The more recent one came with less than 3,000 clicks from Roberts. After a few months the mirror stuck in the up position and it had to go to Nikon repair. Fortunately Roberts picked up the tab for repair. The older one was purchased from a private individual several years ago with 635 clicks on the shutter and worked well up until now. The camera controls seemed frozen and nothing responded - fresh battery, fresh card, different lenses. It is now on the way to Nikon for repair. Neither camera body has more that 6,000 clicks at present. My oldest DSLR a D5300 has been merrily working fine after 4 or 5 years. Due to family situation I don't get to shoot much. I am shocked that both Dfs suffered problems at such a young age. Any comments from Df users are welcome.
PS I consulted Nikon and their recommendations didn't work. They told me to send it in.

Best check with Nikon USA on this as in some cases what Billnikon says may not be totally correct. On NikonUSA website they give the definition of Gray Market as (quote) "Nikon products that are IMPORTED AND SOLD by anyone other than Nikon Inc. USA are considered Gray Market." In your sons case he is not importing the camera to sell rather than for his personal use. I have a friend who ran into a similar problem with purchasing a camera outside of the US. While travelling in Europe he had his Nikon camera stolen in England near the start of his vacation. Since he had a multitude of Nikon lenses he opted to purchase another camera there in England. The seller there was an authorized Nikon dealer for that country and advised him to make sure he kept all documents to prove that point when he returned home. He did so and when he returned home contacted someone at NikonUSA regarding the purchase outside of this country. He was advised that possibly any warranty may not be covered ?? but that in the future as long as he could prove he himself had purchased the equipment from an authorized dealer he would be able to get it repaired (at his expense). So it appears that as long as he keeps the camera and documentation himself it would be acceptable to NikonUSA. However should he sell it he then becomes the importer and it would be Gray Market. This was for a camera purchased in Europe (England) but it may be different for one from China especially with what is going on now between the two of them. Also I wonder if there are many "authorized" Nikon dealers in China that will issue the proper documentation. So it would be best to contact NikonUSA and get the real answer to your question rather than depend on the ramblings of us Hoggers. They do have a chat line on their website (I think)

LittleRed (Ron)

I am relatively new to digital photography. I have three digital cameras, a Nikon Coolpix S7000 point and shoot and two Olympus Micro 4/3 mirrorless cameras, both fairly recent models. All three cameras have 16 megapixels but the point and shoot has a sensor just slightly bigger than a smartphone. The point and shoot photos do not look that good on the camera but when I send them to my phone by WiFi, they look almost (but not quite) as good as the larger format photos. Is there any explanation for this? This suggests to me that sensor size may not be as important as some say it is. The Micro 4/3 photos look great also and are a bit better than those from the point and shoot but the difference is not dramatic. This makes me wonder what the advantage would be for going up to full-frame. Maybe, this has to do with the fact that there is still not a very large image size on the smartphone. I have been on UH for three and a half years and have never posted a topic before. So, thank you for your patience.