R5M2 with RF 18-150?

[OldrockyGN]

Hi - I put my RF 18-150 on my R5m2 and looked thru the viewfinder and it -seemed- to fill the frame. Since this
lens is "designed for crop factor" I was half expecting it to be less than stellar around the edges unless the camera
is put in crop factor mode. I did not take a picture - probably should have.
I'm hoping that someone here has experience with using this lens on a FF camera and can report results ... ???

 

[neuroanatomist]

When you attach an RF-S or EF-S lens, R series cameras automatically enter crop mode.

 

[OldrockyGN]

neuro - thanks ... I think. I don't know if I like the -idea- of crop mode on my FF. if I've done my homework on that
feature it means that the camera will use far less area of the sensor ... enough less than even my R5m2 will be
using less pixels when in crop mode than my R7. I do like the fact that the camera is smart enough to just
enter crop mode all by itself. I will have to -test- with the 18-150 and see if I like the results of it ... especially
doing a compare of the same scene (focal length and lighting) and taking both images thru post to see if the
end results are close enough that I don't care. Since I use the 18-150 for 'landscapes and such' and the 100-500
for birding I may be a happy camper with the crop mode on the R5 for this lens in this situation.

 

[neuroanatomist]

neuro - thanks ... I think. I don't know if I like the -idea- of crop mode on my FF. if I've done my homework on that
feature it means that the camera will use far less area of the sensor ... enough less than even my R5m2 will be using less pixels when in crop mode than my R7.

This is one of those you can’t have your cake and eat it too situations. You wanted Canon to make long telephoto lenses specifically for crop cameras because you thought they would be smaller and lighter. They won’t, because for long lenses, the image circle is not limiting.

The converse of that is that for shorter focal lengths, the image circle IS limiting. The image circle of the RF-S 18-150 just covers the area of a crop sensor. Without crop mode enabled on a FF sensor (which I suspect is locked out in the menu), you’d just see a circle that doesn’t cover the full image. Like this:


That’s why crop mode is automatically enabled. Also, that’s with a lens like the 18-150, which was originally designed for EF-M and actually covers the full APS-C sensor. Newer designs like the RF-S 10-18 don’t even do that without the forced correction of barrel distortion.

 

[AlanF]

If you are reach limited and you are going to crop in post then there is an advantage in using crop mode on your FF: smaller file size, larger image in vf, maybe better AF etc.

 

[SvO2]

If you are reach limited and you are going to crop in post then there is an advantage in using crop mode on your FF: smaller file size, larger image in vf, maybe better AF etc.

The other advantage seems to be faster readout speed in crop mode if the flash sync speeds are anything to go by.