full frame vs crop camera depth of field

[amatula15]

Hi,

I am upgrading from a Canon SL1 crop camera. I had ordered a Canon T8i which is on backorder.
However, a friend, who is a a professional photographer, suggested I upgrade to full-frame.

(In the past year I have been experimenting more and my photography has improved as a result.

I am thinking the Canon RP mirrorless (with RF 35mm F1.8 Macro IS STM lens).

I have read and understand that shallower depth of field with full frame can be attained.
For my flower photography and some landscape, that woudl be great.

However there are times, I do like depth of field in my landscape photography. I often use the 1/3 rule to get as much in focus as possible.

Will it be harder with the full frame camera (RP) to get the depth of field?

Is there anything else I should know / consider?

Thank you and all the best!
Annie

[Ray-uk]

Using the same focal length lens, at the same aperture and at the same distance will give you the same DOF regardless of the sensor size. What causes the apparent change in depth of field is that with different size sensors you need to adjust the camera to subject distance to include the same amount of subject in the shot.

For landscapes the DOF will appear to be pretty much the same unless you are going to include something very close as well as the far distance or if you are going to change the focal length of the lens that you use for the shot.

[amatula15]

Thank you, Ray-uk!

May I ask you on this:

"For landscapes the DOF will appear to be pretty much the same unless you are going to include something very close as well as the far distance"

If I focus 1/3 into the image, should I expect focus throughout the image?

Thank you, again,

Annie

[Waddizzle]

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@amatula15 wrote:

Thank you, Ray-uk!

May I ask you on this:

"For landscapes the DOF will appear to be pretty much the same unless you are going to include something very close as well as the far distance"

If I focus 1/3 into the image, should I expect focus throughout the image?

Thank you, again,

Annie

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Get your hand on a "Depth of Field" app.  I do not subscribe to the idea of a "1/3 Rule."   Do a web search for "hyperfocal distance".  Check the web site dofmaster dot com.

[Ray-uk]

I agree with Wadizzle, dofmaster has all the info you need.

[amatula15]

Thank you, both.

I don't have a cell phone so would not have that with me 😞

But I will check it out!

Out of curiosity why don't you think much of the 1/3 rule?

Thank you, again!

Annie

[Waddizzle]

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@amatula15 wrote:

Thank you, both.

I don't have a cell phone so would not have that with me 😞

But I will check it out!

Out of curiosity why don't you think much of the 1/3 rule?

Thank you, again!

Annie

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Visit the dofmaster web site.  It can do a better job of explaining hyperfocal distance than I can.  Why do I not like the "1/3 Rule"?  For one, you're not applying it correctly.  

Einstein actually had more than one Theory of Relativity.  He first discovered the Special Theory of Relativity, and later announced the discovery of the much broader, and more famous, General Theory of Relativity.  

I would compare the "1/3 Rule" to the Special Theory of Relativity.  It only really applies in "special cases:, or certain shooting scenarios.  I would compare a Depth of Field app, or DoF Table, to the more generic General Theory of Relativity, which covers all scenarios.

[ebiggs1]

Annie,

Perhaps this will make it a bit more clear.

The focal length of lenses that are made especially for crop sensor are not corrected for the crop sensor. This means a 35mm lens for a crop sensor has the same focal length as a 35mm for a full frame. Thus the same DOF. The crop sensor will show only a FOV (field of view) that is equivalent to a 24mm when compared to a full frame sensor.  Remember a lens can not change its FL, ever.  It is what it is no matter what sensor you use it on.