DreDaze wrote in post #17056885
i'm sorry...but i disagree with just about everything written here...first of all...dust isn't showing up in photos...i also doubt fingerprints and scratches are going to have any major impact...and where did you pull this $900 number from?...that'd be the most expensive repair i think i've heard of...
A few years ago, I bought an 8-15mm from a POTN member that had a few hairline scratches. ( I returned it.) The scratches are on all the photos that I was shooting at f8. If I have time today, I will put a fingerprint on my new 8-15 lens and show you the results. Dust on the lens will show too. The reason is because on a 8mm fish eye, the DOF is so great, the front element is nearly in focus. Hence probably one of the reasons why the OP wants to photograph chickens pecking with this fisheye lens.
Naturally, I went to canon in Hollywood to get a quote to replace the front element. With a CPS membership, it was still $900 to replace the front element. (I don't have the quote on paper anymore) Apparently, the front element is a lens module that includes several glass elements.