Cleaning back of lens

Hi folks,

I was wondering if there's a good way to clean the back of an 85mm f1.2 II lens. or should it even be touched at all. i wish canon could've made a better way to protect it. should i just use a blower? is a microfiber cloth a no no? thanks in advance!

i have the lens
what is it you wish to clean?

powhodee wrote in post #9944291
Hi folks,

I was wondering if there's a good way to clean the back of an 85mm f1.2 II lens. or should it even be touched at all. i wish canon could've made a better way to protect it. should i just use a blower? is a microfiber cloth a no no? thanks in advance!

I would say to clean the elements the same, careful way that you would treat any fine optical surface: no compressed air but rocket blower (or equivalent) first, and then any smudges with lens tissue or a micro fiber cloth. Use fluids very very sparingly or not at all.

For "greasy prints" I've used the breath/wipe method for years with no problems.

Like you do the front I guess.

This method is suitable for either end of a photographic lens assembly:

A squeeze-bulb blower such as a Rocket Blower by Giottos, quality lens tissue (such as that sold by Kodak and now Tiffen), a good lens cleaning fluid, and PROPER TECHNIQUE is the way that I have cleaned my lenses for decades.

What is "proper technique"?

First - the goal is to clean the lens (or filter - I would use the very same process) without grinding any dirt/debris into the lens. To me, this absolutely dictates single-use surfaces for anything that touches the lens. That's why I use lens tissues instead of a washable cloth or - particularly - something like a lens pen.

Here are the steps that I use to clean a lens:

1. Use a squeeze-bulb blower to blow any loose dust off the lens. 90% of the time, step 1 is all that is necessary.

2. Take a lens tissue out of the pack. Fold it once, holding only what was the ends of the tissue. You want to be extremely careful to NEVER TOUCH the areas of the lens tissue that will be touching the lens. This will avoid transferring oils from your fingers to the lens.

3. Moisten the folded portion of the lens tissue with a little lens cleaner. You don't want the tissue dripping wet, but it must be damp.

CAUTION: NEVER apply lens cleaner directly to the lens (though it won’t hurt a filter, you don’t want liquid leaking into the lens’ innards).

4. Wipe LIGHTLY across the lens ONCE with the damp tissue. Then either turn it over or fold it so that you can wipe again, but with an unused surface. You can do this as often as needed, as long as you never wipe the lens twice with any surface of the tissue. This prevents scratches. Again, make sure you never touch an area of the tissue that will touch the lens.

5. Ensuring that the lens is actually clean, use a dry tissue, handled the same way as above, to wipe the lens dry. Since you have already removed the dirt, there's no risk of scratching the lens with the dry tissue.

6. Dispose of the used lens tissues in a proper trash receptacle.

That's it in a nutshell. Simple and effective. I've been cleaning my lenses this way for over 40 years, and all of them have pristine glass (and none have ever worn "protective" filters).

...I don't know if it has changed with newer lenses, but the rear element coatings have been typically a good bit softer than the front element coatings.

In any case, I blow it off first with a bulb blower, anything left that looks like it could be gritty gets lightly brushed off with a sable brush, then lightly cleaned with a drop of lens fluid on a lens cloth, finished off lightly with a dry part of the cloth. Main thing is not to scrub at it, just light circular swipes. If you still see some streaks, fog-breath on it and finish off with light strokes.

Good to know. I never use any fluid on lens element anyway.

Lens pen works for me.

Thank you all for tips.. Going to be buying tissues now. Have used the microfiber cloths in the past... ugh

Microfiber cloths are great at collecting dirt and oils, but not very good at letting go of particles that could be abrasive when you wash them. I use dedicated lens cloths only for lenses and wash them in simple non-fatty dish soap. I've never been a fan of paper-based lens tissues, but maybe they are fine.

Are all lens tissues and solution created equal, or are some better than others. I bought some eclipse and pec pads to clean my sensor a few months back. Will these work for lenses as well, or do I need something else?