Per the challenge rules posted on page one of the "What Is It" thread, there is no provision for the exclusion or limitation of challenge items or, the frequency of challenges related to a specific
or one category. As always, good taste and observance of copyright law is paramount.
Players are encouraged to make their challenges as interesting as possible through the use of photographic technique and/or by asking for specific information about a challenge item or to identify something unique about the challenge item. This is especially true if the image used gives away much or all of the item's identity.
Hope this clears the air. :)
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