Question RE EF Lenses on EOS M and other APSC Cameras

[jolyonralph]

You already use the 50mm f/1.8 with an adaptor, so that should tell you the article is nonsense as presumably you're happy with the results!

The 35mm f/2.0 would be a nice partner for the EOS-M - I'm considering getting one myself

 

[mb66energy]

There is another catch on using FF lens on the APSC. The APSC sensor has a multiplication factor of 1.61 linear or 2.59 area. In order to fully utilize the resolution power of the APSC sensor, the FF lens must have 1.61 more resolution power than what is needed for the FF sensor. M3 has a resolution of 24.2 MP. It needs a FF lens with 62.79 MP resolution to fully utilize the resolution power of the M3. How many FF lens can make that claim?? It is unfortunate that Canon does not make a 35mm f2.0 IS EF-M lens.

You need to learn how system resolution works before making patently inaccurate comments like that.

Here is a start: http://www.canonrumors.com/forum/index.php?topic=26938.msg595091#msg595091

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Thanks for pointing it out. I am fully aware of that. As per your quote says. When both sensor and lens resolution are matched. the end resolution is only 71%. If the lens resolution is only 66% of the sensor. The end resolution becomes only 55% of the sensor. That is 21 % reduction from the potential resolution. This is not fully utilize the resolution of the sensor. We spend money to buy expensive equipment, we want to get the most out of it.

How is it that, as you imply, your argument applies to FF lenses used on APS-C cameras, but not APS-C lenses used on APS-C cameras? Or do you believe that APS-C lenses intrinsically deliver higher resolution? Sorry, but I can't really see any relevance to your point in this discussion of using FF lenses on APS-C cameras. Yes, smaller pixels benefit more from higher resolution lenses, but the pixels of the M3 aren't all that much smaller than those on the 5DsR (same density as a 20 MP APS-C sensor).

If anything, since lens resolving power is generally highest in the center and drops toward the periphery, the benefit from using only the center of the FF image circle is quite significant – a glance at the 35/2 IS MTF chart shows resolution remains quite high through area of the APS-C sensor.

I see a better resolution of my EF-S 60 compared to the EF 100 (non-IS) in my images. I am shure that isn't intrinsical but a result of lens optimization for the use case.

A FF lens must have reasonable quality for an image circle of ~43mm while the APS-Lens only needs ~26mm image circle of reasonable IQ.

Classic FF lenses are too optimized for the center region where most subjects in standard compositions are located (e.g. the 24mm 2.8 non-IS) but I am shure that there is some co-optimization in newer lenses for both, FF and APS-C. The 35mm 2.0 is - in my opinion - a good example for a dual use lens with extraordinary resolution within the APS-C image circle and very good res. for the rest of the area.

My conclusion is that an EF-S or a newer EF lens should work optimally on APS-C sensors. Older lenses (pre APS-C era) should be checked.

 

[AE-1Burnham]

Wouldn't it be cool if Canon made a Speedbooster for EF to APSC sensor?! Or if Metabones made a EF to "APSC" or "EF-M" adaptor. God that would make me so happy. (I imagine Canon Corporate would get quite angry at Metabones and out would come lawyers and such...) If this existed I would buy an M series camera immediately.

 

[psychilles]

Wouldn't it be cool if Canon made a Speedbooster for EF to APSC sensor?! Or if Metabones made a EF to "APSC" or "EF-M" adaptor. God that would make me so happy. (I imagine Canon Corporate would get quite angry at Metabones and out would come lawyers and such...) If this existed I would buy an M series camera immediately.

Kinotika says Viltrox is coming out with a EF to EF-M speedbooster
https://www.youtube.com/watch?v=cIcbU6aznNk