TC 1.4

[Crazyhorse]

Hi

On a cropped sensor what is:

The focal length of 70-200

The focal length of 70-200 with 1.4 tc attached

The focal length of 70-200 with 2 x 1.4 tc attached

Many thanks.

Lisa

 

[BRASH]

Hi

On a cropped sensor what is:

The focal length of 70-200

The focal length of 70-200 with 1.4 tc attached

The focal length of 70-200 with 2 x 1.4 tc attached

Many thanks.

Lisa

Depends on the crop of the sensor. Just multiply the focal length by the crop and then x the TC's

 

[Martyn...]

I do not think you can stack 2 1.4TC's, may depend on make of TC.

 

[arad85]

Hi

On a cropped sensor what is:

The focal length of 70-200

70-200.

The focal length of 70-200 with 1.4 tc attached

70x1.4-200x1.4 (~98-280).

The focal length of 70-200 with 2 x 1.4 tc attached

If you can do it, 70x1.4x1.4-200x1.4x1.4 = 140-400

In all cases the field of view will be different depending on the sensor size you are using and zoom setting you are at. The focal length does not change unless you are using a focal length multiplier (or extender).

 

[Crazyhorse]

I do not think you can stack 2 1.4TC's, may depend on make of TC.

Thanks for the replies.

40d (1.6 sensor)

I thought you could stack 2 x 1.4 tc's. (Canon lens 70.200 2.8) and Canon 1.4 tc's.

Lisa

 

[arad85]

Thanks for the replies.

40d (1.6 sensor)

I thought you could stack 2 x 1.4 tc's.

I don't think so either (you'd also have 2 correcting lenses instead of one, so the image quality would degrade). I think that's why you get a 2x TC - it's equivalent to 2x1.4 TCs.

(Canon lens 70.200 2.8) and Canon 1.4 tc's.

Lisa

Don't forget that you lose a stop of light from your aperture when you add a TC. The 2.8 becomes an f4 lens with a 1.4x TC and an f5.6 lens if you use a 2x TC

 

[Martyn...]

Thanks for the replies.

40d (1.6 sensor)

I thought you could stack 2 x 1.4 tc's. (Canon lens 70.200 2.8) and Canon 1.4 tc's.

Lisa

It all depends on the actual construction of the TC, the problem is the glass in the TC actually hitting the glass in the other TC, check first.

I am sure you can stack the Canon 1.4 + 2.0 because of the extra depth of the 2x TC.

 

[Crazyhorse]

Hi

Someone on here posted a pic recently:

http://www.talkphotography.co.uk/forums/showthread.php?t=268775

Lisa

Here's his/her other thread using 2 x 1.4

http://www.talkphotography.co.uk/forums/showthread.php?t=257019