You will be given a definition of a task first, then some input of the task.
You will be given a review about a book, an item, a place or a movie. After that, a question is given that you should answer using a certain span of the review. Your answer should be from the review itself and should not contain extra words, and should not be a combination of different spans. If there's no direct answer to the question, answer with a part of the text that is the most relevant to the question. See the examples for clarification.

review: After purchasing a Nikon D70S with the Sigma 18-200mm lens, I recently purchased a Nikon D200 and a Sigma 10-20mm ultra wide lens. This lens is one of the best I have ever used on any kind of camera. It not only has a good professional look and feel to it, but it works flawlessly with the smoothness of lenses in a much higher price range. Images are clean and crisp, and the autofocus is butter smooth. I paid a bit over $500 for mine and I doubt there is a nickels worth of difference, except in price, between the Sigma brand and a comparable lens bearing the Nikon name. This lens is a keeper for sure!!
question: Where is there a good contrast of colors?
Output:
Images are clean and crisp , and the autofocus is butter smooth