Protection for 300mm glass

[C.S.I.]

While at B+H a few days ago, I was admiring a beautiful piece of glass.....300 2.8 L. I asked the salesperson what size filter is used to protect it, and he said "none". Is this true? The only thing that protects this monstrous piece of glass is the hood?

[HJMinard]

It's true - it does not have front filter threads

[johndm]

While at B+H a few days ago, I was admiring a beautiful piece of glass.....300 2.8 L. I asked the salesperson what size filter is used to protect it, and he said "none". Is this true? The only thing that protects this monstrous piece of glass is the hood?

EF 300mm f/2.8L IS USM

Product Specification

http://www.canon.co.uk/Images/14_24787.gifhttp://www.canon.co.uk/Images/14_24787.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gif Angle of view (horzntl, vertl, diagnl)

6°50', 4°35', 8°15' http://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24787.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gif Lens construction (elements/groups)

17/13 http://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24787.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gif No. of diaphragm blades

8 http://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24787.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gif Minimum aperture

32 http://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24787.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gif Closest focusing distance (m)

2.5 http://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24787.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gif Maximum magnification (x)

0.13 http://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24787.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gif AF actuator

USM¹ http://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24787.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gif Filter diameter (mm)

52 Drop-in http://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24787.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gif Max. diameter x length (mm)

128 x 252 http://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24787.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gif Weight (g)

2,550 http://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24787.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gif Magnification with Extension Tube EF12

0.18 - 0.04 http://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24787.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gif Magnification with Extension Tube EF25

0.24 - 0.09 http://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24787.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gif Lens hood

ET-120 http://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24787.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gif Hard case

Lens Case 300 http://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24787.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gif Soft case

- http://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24787.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gif G.F.Holder III (hood III*)

NC http://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24787.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gifhttp://www.canon.co.uk/Images/14_24788.gif G.F.Holder IV (hood IV*)

NC

[KennyG]

The front glass is actually just that, about $300 worth of glass that is designed to protect the innards. However, the more accurate answer is the hood protects the lens. It does an excellent job, never marked the front glass of mine yet and it gets a lot of use in adverse conditions.


I park mine hood down with camera mounted, on the ground, trackside. That's why there is a rubber edge around the hood. You will find the majority of owners of these lenses use them a lot and they are regarded as a tool rather than something to be admired.