General APS-C F-Stop

[RickyRed]

How many photographers believe using a APSC camera, Let's say a 24-106 F4. That you lose one F-stop of light, so it turns to F 5.6? RJ

 

[chipman]

For me this is a hobby. As long as a camera produces the pictures I want I'm not going to suck the fun out of it worrying about the details.
Life's too short, and I don't have that much left.

 

[Skyblot]

Not me!
That's how exposure works: shutter speed & f stop & ISO = exposure value. No one asks what the sensor/film size is. The lens is designed for a given image area, if you only use a portion of the area by cropping it does not affect the amount of light per unit area falling onto the sensor/film.

 

[RickyRed]

Not me!
That's how exposure works: shutter speed & f stop & ISO = exposure value. No one asks what the sensor/film size is. The lens is designed for a given image area, if you only use a portion of the area by cropping it does not affect the amount of light per unit area falling onto the sensor/film.

There you go. An f4 lens is a f4 lens, what people get wrong, A F4 lens used on a Apsc ,the depth of field is F5.6, It was just a fun question,thats all. I love the R7,but it has some glaring faults. One of the biggest would be the shutter. And a better view finder

 

[Dean Wilson]

An aperture delivers the exact same light intensity (brightness) per square millimeter to both a full-frame sensor and a crop sensor at the same shutter speed and ISO. Your shutter speed and ISO readings do not change.

Because a crop sensor is physically smaller, it collects less total light from the overall image circle projected by the lens.

While the exposure per unit area is identical, the smaller total light collection on a crop sensor generally leads to a lower signal-to-noise ratio (more grain/noise at high ISOs) and a deeper effective depth of field compared to a full-frame setup

 

[RickyRed]

Yes,thats why using 2.8 and 1.8 lens on a APSC lets more light and lower your ISO. demands. Also true on full frame. 24-105 2.8 paired with the R5 has been fantastic combo. RJ

 

[Skyblot]

There you go. An f4 lens is a f4 lens, what people get wrong, A F4 lens used on a Apsc ,the depth of field is F5.6, It was just a fun question,thats all. I love the R7,but it has some glaring faults. One of the biggest would be the shutter. And a better view finder

Yep, the R7 isn't perfect and to be honest I have struggled with it for the first few months. I was seriously wondering if I should have bought the R10 instead. It's not been the rolling shutter, or the autofocus settings, but instead it's been the effect of the high resolution sensor and how it is terribly unforgiving of any sloppiness in camera handling and aperture/depth of field. (Aperture - that's my tie back to your original question.) To be fair, I would have the same issue if I'd bought an EOS90D or a 40mpx full frame.

Photos viewed at normal print size - 6x4, 8x10 etc all look great, but viewed on screen at 100% magnification and the sensor is great at picking out any movement or focus errors. And the majority of time we look at photos on a screen. And zoom in. Just because we can.

Check the two versions of this image, 150mm @ f11, the focus distance was 1 metre.
The full image is the out of camera jpg (s1 size), and the flower looks sharp and the background blurred. Standard depth of field calculator predicts a DoF of about 3cm. Adequate for the subject.
The second image is a crop at 100% view from the raw file processed in DXO PR, and the depth of field is obviously much less - almost nothing - the stem is sharp but the other bits are not. Finding an advanced DoF calculator that allows adjustment of viewing size (zoom) and visual acuity (sensor pixel size) then gives a DoF of 0cm.

This camera has taught me more about aperture and DoF than my previous 4 decades with a camera.
And also that it is important to to start with the end in mind and to not obsess over the tiny details.

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