What is the meaning of the red words?

[hwchoy]

DOF scale is explained here

http://jimdoty.com/Tips/Depth_of_Field/depth_of_field.html

pictures as well

ortega, they show pix of a prime lens scale. anyone has seen such scales on a canon zoom?

 

[Artosoft]

This one need Canon specialist to explain :bsmilie: .

Regards,
Arto.

 

[user12343]

tink DOF scales are only engraved for certain prime lenses only. eg, 50mm, 85mm, etc

for recent zoom lens, there is no DOF scales etched on the barrel assembly.

 

[hwchoy]

so the red ones are IR scales? like very big differences from the optical focus leh.

 

[ortega]

older zoom lenses have DOF scale and IR scale

see here

 

[ortega]

better to ask this in the Canon Sub forum
you need a canon user with a manual

 

[hwchoy]

nice scale! I think they had to do away with those on the cheapo two-tube zooms, and also the 80-200 is non-extending so nowhere to put the scale I guess.

 

[hwchoy]

better to ask this in the Canon Sub forum
you need a canon user with a manual

good idea I will do that.

 

[user12343]

those were the good days when we can see fancy parabolic lines indicating DOF scales on zoom lens, but nowadays, most zoom mechanism of recent glasses is by the rotating ring and not commonly-found push-pull type (where high tendency of zoom creep).

 

[lsisaxon]

so the red ones are IR scales? like very big differences from the optical focus leh.

Yes. Checked with a photographer friend using Canon, he confirms it's for IR.

 

[hwchoy]

Yes. Checked with a photographer friend using Canon, he confirms it's for IR.

thanx! actually I was hoping it is for hyperfocal.

 

[Artosoft]

thanx! actually I was hoping it is for hyperfocal.

OT a bit, did the camera set hyperfocal distance when put on landscape mode? Or it is only set at infinity distance?

Thanks!

Regards,
Arto.

 

[lsisaxon]

OT a bit, did the camera set hyperfocal distance when put on landscape mode? Or it is only set at infinity distance?

Thanks!

Regards,
Arto.

Wah.. the camera so smart ah?

 

[Artosoft]

Wah.. the camera so smart ah?

Hopefully lah....

To find a reason to use landscape mode (I am P, A, S, M mode user) :bsmilie: .

Regards,
Arto.

 

[yanyewkay]

Yes. Checked with a photographer friend using Canon, he confirms it's for IR.

this leads to another question I have in mind after reading catchlight's post that it was IR markings and 2nd confirmed by you. Why have markings for IR?

very useful for catchlights but for others?

 

[catchlights]

this leads to another question I have in mind after reading catchlight's post that it was IR markings and 2nd confirmed by you. Why have markings for IR?

very useful for catchlights but for others?

come on lar...
I'm not the only one shoot IR, anyway, nikon af lens don't have IR marking also.

 

[Ah Pao]

Paiseh, me bad.
Didn't do a more through research before posting.

If it's for IR focus, how do they work?

EDIT: http://heim.ifi.uio.no/~gisle/photo/ir.html#tech
A pretty good explaination of how to use the scales.

 

[hwchoy]

It is IR ah, someone showed me the manual for the 28-135 liao.

 

[yanyewkay]

;p but you use it in your work, i think probably more than the weekend shooters? :think: interesting.. never knew such scales existed.

 

[catchlights]

;p but you use it in your work, i think probably more than the weekend shooters? :think: interesting.. never knew such scales existed.

you can find it on almost all the old prime lens.