What is, in your opinion, the best lens cleaner? Which do you think is the most effective/best value for your money/most easy to use, etc.
Please include advantages/disadvantages as well as price and link.
The Lens Pen is my favorite first line of lens cleaning. This is a pen-shaped tool with a very light non-abrasive brush on one side and a powdered cleaning agent on the other.
Always brush first to remove an particles from the lens surface. If there are marks stuck to the lens then I use the cleaning side to remove it. This is very effective and minimizes the risk of damaging the lens surface but rubbing grit over it.
There are sometimes marks which do not come off with the lens pen and for those I use a wet-solution but always after brushing away particles. This is called a Residual Oil Remover (ROR) or Optical Glass Cleaner bought from a camera store. With this, I also buy disposable lens tissues to wide the liquid and not end-up with a cloth which may accumulate particles harmful to lenses.
My camera bag always contains ALL of these because there is no perfect solution for all situations. The key is to be as gentle as is effective.
Eclipse is an extremely clean filtered methanol solution, that leaves no residue on glass and other optics. Likewise, the Pec-Pads are a woven, lint-free disposable cloth that is excellent for cleaning optics. Unlike regular lens tissue, these are very absorbent, so you are not smearing solution around the lens. These are recommended as part of the 'copperhill method' of sensor cleaning, and a bottle/100 wipe pack will last you a lifetime of sensor cleaning, meaning there is plenty left over for critical lens cleaning.
Note that I use these products primarily in the home, prior to a shoot, or after a shoot. In the field, I use a lens brush, and a microfiber cloth for emergency purposes. I prefer to NOT touch the lens in any fashion in the field, but sometimes you can not avoid or prevent it.
Response to question below about blower: Yes I do use and recommend a blower, and it can indeed be a useful addition to your bag. I recommend the Giottos Rocket Blower, as it is inexpensive, and it has a filter on the intake, which helps reduce dust being blasted out of the blower onto your equipment. Note however that they can be kinda bulky, and its usually one of the first things to get tossed out of the bag if I am traveling light. Also, don't over think this: your mouth makes a workable blower in a pinch, and is dust free, though not necessarily liquid free (see cleaner above).
I'm using a lens pen and rocket blower when on the road. At home I use Pancro lens cleaner with Rosco lens tissues and canned air to clean my lenses and filters. The cleaner and tissues are the standard in the movie industry where it's used to clean the expensive motion picture lenses. One bottle should last for years.
I clean my lenses in this order until the problem is taken care of:
If something is obviously gooey, oily residue I go straight to the Pec-Pad/lens cleaner option, rather than contaminate my reusable items.
This order is determined by what is least likely to damage the surface and coatings of the lens. It does appear, however to also be roughly in order from cheapest to most costly method. An air blower has an initial cost of around $7-10 and no per use cost. I still haven't worn out my first one. Microfiber cloths are relatively inexpensive, especially when purchased in bulk, but I discard them when they become dirty, rather than try to wash them (once they are too dirty for my photo gear, I use them for household duties). The brush end of a Lens Pen is just as durable and cost effective as an air blower, but the cleaning tip eventually wears out and the entire Lens Pen needs to be replaced at a cost of around $6-10. Pec-Pads and lens fluid are obviously single use items, but are also very affordable (About $8 for 100 4X4 pads and $3-4 for 3oz. of fluid). When in the field, I have my blower, Lens Pen, and microfiber cloth with me. Also a small amount of lens cleaning fluid that can be used in conjunction with the microfiber cloth if needed and several individually packaged lint free clothes pre-moistened with isopropyl alcohol.
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