A few 17-40 L questions

Red Bull

I just ordered my 17-40 L lens (yay!) and was wondering a few things. First off, what does the rear gelatin holder thing look like? How does a filter insert in the rear? (photos of this, anyone?)

Also, what should I use to clean the lens? I actually don't have anything to clean my lenses with. I usually just brush off small particles off with thin lens cleaning paper for my other lenses. I want to actually have something that can clean it good in case something like a fingerprint or anything else gets on the front element. Would a cheap lens cleaning kit work fine (say from my local Ritz camera store) or is there something else that I should use? I may get a UV filter for when I don't use the hood (indoors) but I will usually have the lens hood on so that should protect it fairly well. I've been using the lens hood on my 70-200 L to protect the front element and it's worked fine so far.

DavidTO

Red Bull wrote:

I just ordered my 17-40 L lens (yay!) and was wondering a few things. First off, what does the rear gelatin holder thing look like? How does a filter insert in the rear? (photos of this, anyone?)

I assume you ordered from B&H? I had the same confusion about the gelatin holder. I can explain it to you in terms that are very simple to imagine. It doesn't exist. There is no rear gelatin holder.

Red Bull

Yes I ordered from B&H. It doesn't exist? I've heard on a lot of other sites that it accepts gelatin filters. It also mentions it on Canon's official website.

It has a constant f/4 maximum aperture, and offers the choice of screw-in 77mm filters or a holder in the rear of the lens for up to three gel filters.

Link

Red Bull

So I think I found out about the gel filters. I read that it isn't really a drop in gel filter. You can slide filter cutouts (I guess that's what you would call them) into the back of the lens.

So now how about cleaning the lens? Can somebody answer my previous question about cleaners?

Bob Bell

For cleaning filters or lense I use PecPads with Eclipse fluid. I keep UV filters on all the time so I don't clean lenses often. For rain I just use Pecpads to get the droplets off.

pathfinder

First of all - don't be obsessive about cleaning lenses.

A few dust motes are best ignored.

If there are several dust motes a lens brush or a camel hair brush can be used to gently remove them.

If there are spots that are not moveable with gentle lens brush, or a rocket blower, then you may need a solvent.

A fine drop of distilled water can be used with a microfibre lens cleaning cloth. If that does not work, a tiny drop of Eclipse is ok. PecPads are excellent if used gently.

I used a spray bottle of lens cleaning solution that is distilled water and about 20% isoppropyl alcohol if the lens seems to have greasy stuff on it, followed by a microfibre cleaning cloth. Or a PecPad, or a Sensor Swab.

But as I said first, I RARELY clean my lenses. Only under duress.

DanielB

what about lens cleaners that are used for glasses

Red Bull

Thanks for the help. So should a regular lens cleaning kit work fine? They usually come with a microfiber cloth and solution. I rarely clean my lenses too, but I want to have something just in case something substantial gets on it.

pathfinder

Most of them are distilled water and a little alcohol and should be fine.

Just be sure to not get so much on the lens it can get around the edge to the back of the lens element. Just the tiniest bit of a mist.

Zeiss eyeglass cleaning pads are alcohol and water also.

pathfinder

pathfinder wrote:

Most of them are distilled water and a little alcohol and should be fine.

Just be sure to not get so much on the lens it can get around the edge to the back of the lens element. Just the tiniest bit of a mist.

Zeiss eyeglass cleaning pads are alcohol and water also.

Lens cleaning kits should be fine.

Bob Bell

Watch out for microfibre clothes, unless you wash them perfectly each time, they can damage coatings or scratch the glass. Thats why I use pecpads, each one is clean and are 1 time use. a 100 pack is $6.50

pathfinder

That's why I said not to be too obsessive about cleaning lenses.:):

You are correct of course, Bob, but microfibre lens cloths sold for use as lens cleaners should be reasonably free of grit.

The truth is that I clean my spectacles with an old multi-washed cotton bandana, and have never seen any scratches on the anti-reflection coating on my glasses. And I use the same cloth carefully on my L glass IF NEEDED. But, I prefer to just use a rocket blower or a lens brush if possible.