Crop factor in calculations
Aug 21, 2019 20:46:58 #
Greetings everyone,
I recently purchased a Canon EOS Rebel T7i. I also purchased a "nifty fifty" lens for it as well. My question is when I am trying to calculate a formula using the focal length of the lense ( such as DOF) should I use the raw focal length of the lense or should I use the focal length x crop factor to calculate it? For example, it's a 50mm lens, but when you use the crop factor it's 50mm x 1.6= 80mm. Which one should I plug into my DOF calculator to find my DOF?
Thank you,
Elfman9
I recently purchased a Canon EOS Rebel T7i. I also purchased a "nifty fifty" lens for it as well. My question is when I am trying to calculate a formula using the focal length of the lense ( such as DOF) should I use the raw focal length of the lense or should I use the focal length x crop factor to calculate it? For example, it's a 50mm lens, but when you use the crop factor it's 50mm x 1.6= 80mm. Which one should I plug into my DOF calculator to find my DOF?
Thank you,
Elfman9
Aug 21, 2019 20:57:11 #
For the effective focal length, "use the focal length x crop factor to calculate it."
Elfman9 wrote:
Greetings everyone, br br I recently purchased a... (show quote)
Aug 21, 2019 20:58:56 #
Your DOF calculator should ask you the type of camera. Therefore, you'd specify distance, aperture, actual focal length (50mm in this example) and the camera type (T7i in this example, or any Canon crop-sensor model - all EOS Rebels, EOS ##D models, and / or 7D versions).
Aug 21, 2019 20:59:55 #
Elfman9 wrote:
Greetings everyone, br br I recently purchased a... (show quote)
The real focal length AND the camera model or crop factor.
Aug 21, 2019 22:44:57 #
Strodav
Loc: Houston, Tx
Elfman9 wrote:
Greetings everyone, br br I recently purchased a... (show quote)
https://www.cambridgeincolour.com/tutorials/dof-calculator.htm
Aug 22, 2019 06:48:40 #
gmar3180
Loc: Waxahachie, TX
Elfman9 wrote:
Greetings everyone, br br I recently purchased a... (show quote)
https://www.photopills.com/calculators/dof
Aug 22, 2019 07:11:30 #
Aug 22, 2019 07:45:39 #
Picture Taker
Loc: Michigan Thumb
The Canon crop factor is correct at 1.6 times. I use a 7D (Cropped) and a 5D (full frame) and have the size of each taped on the lens cap. 100/160 or 100-200/160-320 on zoom
Aug 22, 2019 08:35:20 #
You multiply the focal length times 1.6 ... and ... you multiply the f stop by 1.6 to get what the FF equivalent would be.
Aug 22, 2019 10:13:33 #
Elfman9 wrote:
Greetings everyone, br br I recently purchased a... (show quote)
The Lens focal length (50mm) x the 1.6 crop factor = ??
Aug 22, 2019 10:24:37 #
50mm x 1.6 = 80mm. The 80mm result gives the effective focal length.
Or put another way, the 50mm lens equates to an 80mm lens in focal length when used on a cropped sensor camera.
Or put another way, the 50mm lens equates to an 80mm lens in focal length when used on a cropped sensor camera.
Silverman wrote:
The Lens focal length (50mm) x the 1.6 crop factor = ??
Aug 22, 2019 10:56:57 #
Elfman9 wrote:
Greetings everyone, br br I recently purchased a... (show quote)
It might be a lot easier just to use the DOF preview on the camera.
Aug 22, 2019 11:30:50 #
Aug 22, 2019 12:28:37 #
The online DOF calculator lets you enter your camera and focal length and f stop and distance so you don't need to calculate anything.
https://www.dofmaster.com/dofjs.html
https://www.dofmaster.com/dofjs.html
Aug 22, 2019 12:31:52 #
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