Canon EF 500mm f/4 L IS - inside barrel wall material

[Sinh Nhut Nguyen]

Hello,

Asking owners of the 1st generation IS super telephotos for your opinions on the material of the barrel wall and how it looks.

When looking into my 500 f/4 L IS 1st gen last night I noticed the barrel is outlined with some sort of felt fabric, I assume it is similiar material used in the interior of lens hoods. When I shine my flashlight into the barrel of the lens this material looks fuzzy and has the silverist-aluminum color, (sorry can't find a better way to explain this). At first I though it was fungi that are growing but it doesn't look anything like fungus from what I saw online and also the elements are all clean and I can't even spot a spect of dust. I live in a very dry enviroment of Southern California, my indoor humidity rarely ever go above 40%.

Sorry for posting too many threads the last few days, recently caught the photography bug and wanted to give this thing another try. My gears have been rarely used the last 5-7 years, just wanted to make sure they're still in good condition, my 13 year old 500 f/4 L IS has always been my pride and joy.

[HDNitehawk]

Hello,
When I shine my flashlight into the barrel of the lens this material looks fuzzy

Fuzzy is only bad if it takes Fuzzy pictures.

I would go shot it and see how it does. Then not worry about it.

[Kayaker72]

but it doesn't look anything like fungus from what I saw online and also the elements are all clean and I can't even spot a spect of dust.

As I was reading, I was thinking you had lens fungus/mold. But you checked for that. Also...elements clean. Have you taken a shot or two, even around the house? How do they look?

I have the Mk II version. There are felt like materials in between each element against the sidewalls. I suspect what you are seeing is the material itself or if you see something sitting on it, perhaps the felt doing its job and trapping dust.

[Sinh Nhut Nguyen]

As I was reading, I was thinking you had lens fungus/mold. But you checked for that. Also...elements clean. Have you taken a shot or two, even around the house? How do they look?

I have the Mk II version. There are felt like materials in between each element against the sidewalls. I suspect what you are seeing is the material itself or if you see something sitting on it, perhaps the felt doing its job and trapping dust.

I had chance to compare a friend's 500 f/4L IS and his showed the same characteristics. The right word I should have used is "sparkly" when a bright light is shined on them. Lens performed flawlessly. I missed an opportunity to buy a 70-200 f/2.8L IS II for $800 two weeks ago because that lens sat unused for years and the AF stopped working so I became paranoid with all my unused gears.

[Fast Glass]

I'll take a look at my 500mm f/4 IS tomorrow morning.

I'm very glad I purchased it. And while I often wish for a 600mm f/4 IS, I don't miss the nearly 12lbs it weighs! My hands are really sore from all the birding I've been doing with it. Still a chunk of a lens.

But a 600 will probably be in my future.

[Fast Glass]

So yes, I would describe it as having flocking on the inside of the lens as well and has that look you are describing. And mine is also in mint condition and was stored with a dry pack inside the case.

Glad you caught the bug again! I know you took some fantastic photos and I have been getting back in to bird photography in a serious way as well.