canon 35mm f2 is usm

[kevin2]

can anyone tell me what the fixed marks 22 11 and the red dot on the focus ring indicator signify

[Waddizzle · Accepted solution]

The numbers are an aperture settings.  They are showing the approximate depth of field at those aperture settings.  As you vary the focus, you can read off of the focus ring how deep the DoF would be.

The lens in the image is focused at the hyperfocal distance.  I am not sure about the red dot.  

[kevin2]

Thanks

[shadowsports]

Red dot on hyper focal distance scale.

Good questions.

Its the infrared focusing mark.  Believe its a carry over from days gone by.  With infrared film you actually had to focus at a different place than normal because the infrared spectrum of light is different than what we see with our eyes.  No idea how to replicate digitally, but I guess it can still be done. 

*****All 3 of us posted over one another  LoL

[ebiggs1]

"*****All 3 of us posted over one another"

It would seem so. 

In fact most lenses don't have many marks on them at all anymore.

[kvbarkley]

The cool adaptive LCD display on my 70-300 II does not have an infrared mark. 8^)

I am hoping for a firmware update so that it will show the hyperfocal distance.

[kvbarkley]

The red dot is for infrared focus, because the wavelength is different, you need to focus at a slightly different point. It does not mean much for a DSLR. 8^)

[kevin2 · Accepted solution]

Thanks everyone. Appreciate your help and knowledge