Help Needed > Filter Hitting Front of 17-40L Lens?

Hi guys,

I just purchased a Hoya Super HMC UV(0) 77 mm filter for my 17-40L and was wondering if the protruding lens element in the front of the 17-40L will hit the filter? Anyone using this filter on a 17-40L? I can't quite make it out, and I am afraid to scratch the front element.

Thanks,

Pradeep

in the B&H accessories they list a Canon "sharp cut" (which I bought) or a "thin" version from Hoya or someone else. I guess that it is an issue but not having bought a regular one I couldn't say whether it will hit the lens. Must be a close call.

I am using a Hoya Super HMC Pro-1 on the 17-40L with no issues.

It seems very close but not actually touching...I tried putting a small piece of paper confetti to see if it will move around, but I couldn't get that to work right.

The front element does not rotate, but I don't want to ever have the filter to eventually scratch the front element.

Is the Pro-1 the slimmer profiled one? My filter's body is about 5 mm thick.

I can't find the tape measure but according to the box the PRO-1 has "super slim 1mm glass and 3mm ring with front thread".

With filters very close to the front element you can get the "Newton Ring" effect of concentric circles. They tend to show up in bright or dark areas. You have to be very careful which filter you pick to go with this lens.

I have the same filter. I fits OK on that lens. However, do you notice any "smearing" on the inside surface when you clean it? I have a real problem with that particular filter and am about to send to Hoya and ask for a replacemnent. They did not respond to an e-mail

I have the Hoya S-HMC UV(0) on my 17-40. It really does look like the front element will hit, but it doesn't.

Yeah, you can get smearing, especially if you nick it with something made of protein (ie fingernails). My lenspen doohickey can remove the smears though, so you may want to try that.

Can you show us an example of the Newton Rings?

Thanks for the info. I figured that Canon would not design it to hit filters, since filters are commonly used, but I had to make sure.

If Canon didn't want you putting filters on the front of the lens, then they wouldn't have put any filter screw threads on it.

---Bob Gross---

Your sublime wisdom knows no bounds.

I am not a paranoid type, but for some reason I felt maybe that I was overlooking something obvious. The 17-40L is my first L glass.

I thank you all for your help.

Here is a Newton Ring sample I tracked down: http://www.kmaisch.com …scapes/maria_st​ars?full=1

You can see the effect just above and to the left of the house.

For an explanation of the effect, read this: http://www.fas.harvard​.edu …nsRings/Newtons​Rings.html