1.6 Crop Factor (Page 3): Oh, I agree that the sensor differences will have an affect on the resolution of the image, but not the image that the sensor sees. The size of the sensor...

Longshadow Loc: Audubon, PA, United States

ggab wrote:

So you agree, sensor differences matter?

Oh, I agree that the sensor differences will have an affect on the resolution of the image, but not the image that the sensor sees. The size of the sensor does that (ie. 1.6 crop factor).

bleirer

Perspective in the sense of the relative size of distant objects and depth of field is another oddball thing, we think it is controlled by focal length but really the factor is the camera's distance to the subject. If the equivalent focal length is larger one must be farther away to still fill the frame with the same size subject, so we perceive it as a function of focal length, one's head spins by trying to keep it all straight.

ggab Loc: ?

Longshadow wrote:

Oh, I agree that the sensor differences will have an affect on the resolution of the image, but not the image that the sensor sees. The size of the sensor does that (ie. 1.6 crop factor).

Ok, common ground.
Now let's expand this.

I shoot wildlife. I use a 7D Mark II as my primary camera and the 5D Mk IV as my secondary camera.
The 7d MK II has a 20 mpx sensor and the 5D MK IV has a 30 mpx sensor.
When I shoot from the 5D MK IV and crop the image to match the image created by the 7D MK II, the resolution of the image is close,18.75mpx vs 20mpx. The 7D is slightly more, however the difference is neg.

I am matching the equivalent FOV of the 5D MK IV to the FOV of the 7D MK II. Doing this, sensor pixel density/resolution becomes very important. While the image area I will see is the same in the end, the detail related to what I see will vary if the resolution delta is too large.

It is a real world utilization of FOV looking for a Full Frame camera that will match my crop sensor camera fov and resolution.

Longshadow Loc: Audubon, PA, United States

ggab wrote:

Ok, common ground. br Now let's expand this. br b... (show quote)

Now, arbitrarily, what would happen if the pixel density for a full frame camera was the same as the pixel density for the crop sensor camera. The only difference would still be the field of view between the two cameras.
Any pixel density difference is simply another problem/phenomenon, unrelated to what the camera actually sees, but how (the quality of) it captures of the image. It may matter to some people, but is still a separate scenario. And yes that difference still exists.

ggab Loc: ?

Longshadow wrote:

Now, arbitrarily, what would happen if the pixel d... (show quote)

If I was looking to match the FOV of a FF camera with my Crop Sensor Camera, and both used a 20mpx sensor, the resolution (or ability to show detail) of the image cropped from the FF Camera would be roughly 12mpx. Much less than what is provided by the crop sensor camera.

We agree, we are just focusing (no pun intended) on different things.

Architect1776 Loc: In my mind

Hamltnblue wrote:

What camera are you using?

Canon crop as far as I know are all 1.6. Other APSC are 1.5 with a few oddball exceptions.

bleirer

Longshadow wrote:

Now, arbitrarily, what would happen if the pixel d... (show quote)

Plus if the pixel count is the same but the sensor is bigger, you get an extra advantage of larger photosites, theoretically meaning less noise, less diffraction, better dynamic range, probably other advantages to the large sensor. If the photosite size is the same you get more pixels on the larger sensor.

ggab Loc: ?

MT Shooter wrote:

You need to recheck your math. A 20MP FF camera (Canon) shot at APS-C crop mode yields approx 42% of the FF image, or 8.2MP image size.

Hence my final assumption.
Thanks for the correction.

Longshadow Loc: Audubon, PA, United States

ggab wrote:

If I was looking to match the FOV of a FF camera with my Crop Sensor Camera, and both used a 20mpx sensor, the resolution (or ability to show detail) of the image cropped from the FF Camera would be roughly 12mpx. Much less than what is provided by the crop sensor camera.

We agree, we are just focusing (no pun intended) on different things.

ggab Loc: ?

MT Shooter wrote:

You need to recheck your math. A 20MP FF camera (Canon) shot at APS-C crop mode yields approx 42% of the FF image, or 8.2MP image size.

Are you sure?
The reciprocal of 1.6 is .625.
When 20mpx is multiplied by .625 the result is 12.56.
The delta is 7.44 mpx.

MT Shooter Loc: Montana

ggab wrote:

Are you sure?
The reciprocal of 1.6 is .625.
When 20mpx is multiplied by .625 the result is 12.56.
The delta is 7.44 mpx.

Look at the sensor AREA, and NOT the crop factor. Crop factor is determined from the diagonal measure difference, which has nothing at all to do with the pixels contained thereon.

Longshadow Loc: Audubon, PA, United States

bleirer wrote:

Plus if the pixel count is the same but the sensor is bigger, you get an extra advantage of larger photosites, theoretically meaning less noise, less diffraction, better dynamic range, probably other advantages to the large sensor. If the photosite size is the same you get more pixels on the larger sensor.

Again, additional scenarios.

ggab Loc: ?

MT Shooter wrote:

Look at the sensor AREA, and NOT the crop factor. Crop factor is determined from the diagonal measure difference, which has nothing at all to do with the pixels contained thereon.

From Ziess.com "Making Sense of Sensors – Full Frame vs. APS-C"
"The crop factor
The crop factor allows you to figure out what the field of view would be in a 35-mm film format equivalent camera based on the actual focal length you are using on a APS-C camera. It also helps you compare lenses. The crop factor is always calculated by dividing the full format size by the size of the APS sensor. Let’s take an example.
Suppose your APS-C image sensor is 25.1 x 15.7mm. If you divide 36mm by 25.1mm (36/25.1), you get 1.43. That’s the crop factor. If you put a 70-mm lens on a digital SLR camera that has an APS-C image sensor and multiply this focal length by the crop factor (70 x 1.43 = 100), you would produce the same field of view as if you were using a 100mm focal-length lens on a full frame camera. Crop factors for digital SLR cameras can vary between 1.3x and 2x. The higher the crop factor, the more zoomed in the image will appear."

Assumption: Ziess.com got it right.

MT Shooter Loc: Montana

ggab wrote:

From Ziess.com "Making Sense of Sensors – Ful... (show quote)

In that case just show me one single sensor with a 1.43 crop factor. Refusing to see the obvious is no excuse.

Picture Taker Loc: Michigan Thumb

The lens designation is in relation to a full frame (old 35mm) camera. The crop factor depends on the brand of camera. It can't cover the full view to your size screen, thus it crops it and give you a boost ti magnification.