APS vs FF cropping

[XKAES]

Maybe this has been discussed, but I haven't searched.

Will there be any substantive difference between an APS-sized image and a FF-sized image computer-cropped to APS size -- all other factors being the same (camera, lens, exposure, ISO, image quailty, etc.)? This assumes, of course, a FF camera that has a setting for the APS size.

[Pieter]

Yes: flexibility. In post you can take that APS-C crop anywhere you like within that larger fullframe image. When you set your camera to crop mode, you'll have to get your framing spot on out in the field.

[Phormula]

As far as the final result is considered, there is no difference.

From a practical point of view, as already said, it is better to computer-crop, since you can crop more precisely and experiment different croppings, while cropping in camera means framing it right from the beginning, like in the old days of slide film. Actually, the only reason to do APS cropping in a FF camera is when, for whatever reason, you need to use a lens specifically designed for APS format and the camera does not recognise the lens and performs APS cropping automatically.

[FunWithCameras]

If you choose to crop in the centre, there will be no difference in the resulting image. Well no difference other than the sensor - the image falling on the sensor will be the same, but there may be differences between the APS-C and FF sensors (for example, comparing the A7RV with the A6700). If you are comparing the APS-C crop on the same camera as the FF version, then even that difference disappears.

As already remarked, if you are starting with the FF RAW, you have the option to crop somewhere other than in the centre. If you grabbed a once-in-a-lifetime shot, and it was off-centre, then the APS-C image might clip the subject, but the FF image might have it unclipped.

The cost of shooting the FF image is the space it takes on the card (you might need larger cards, or more of them) and the space it takes on the hard disk (might need larger hard drives or more of them, especially if you keep all your RAWs). Oh, and the small amount of extra electricity you consume in processing the larger RAW file. If you use Lightroom, you may need to make another coffer while it sucks in and processes the folder of larger images, too.

Those are all costs I'm willing to wear most of the time. I only carry an APS-C camera when I'm going to be walking a long way, and the weight matters.

[jackb61]

I think you have to consider resolution. If you apsc camera is the a6700 with 26 mp you will have a 26 mp image. If your ff camera is a a7C II with 33mp, and you shoot in crop mode you will have a 14mp image (because it crops away a lot of pixels to go from ff to crop). On screen they will look identical but if you make large prints you may see some differences.

That said, if your ff camera is the a7CR with 61 mp and you shoot in crop mode you will have a 26 mp image. In this case everything should be identical, even how large you can print.