topic Why Use A APS-C Lens With Full Frame Camera in EF & RF Lenses

Why Use A APS-C Lens With Full Frame Camera

Cantrell — Mon, 23 Jun 2025 22:20:37 GMT

All,

I was in a camera store last week and the rep that I was talking to mentioned using a APS-C lens with a full frame camera. With a Canon you are losing 60% of your pixels or only using 40 % of your pixels. Why would you want to use that combination?

Thank you

Re: Why Use A APS-C Lens With Full Frame Camera

justadude — Mon, 23 Jun 2025 23:09:39 GMT

Did you ask the rep why? There are times when it's ok, depending on what you are doing, but I would not make a habit of it b because you do downgrade the image due to the loss of size. But still, sometimes it works perfectly fine...

For example, my wife has a EF-S 60mm macro lens that she will occasionally use on her RP. However, she just uses the images for her social media, or small prints (16" x 20" is her common size), where it's fine.

I shoot a lot of film. For any of my 35mm film I have a dedicated scanner that holds these small negatives. For any 120 or 620 film I do not have a scanner for the larger size of this film. That same 60mm macro lens on my R6 Mk ll works perfectly to take a photo of the negative while backlit (digital scanning) then I flip it in Lightroom to make a positive. I actually have made some 24" x 24" prints from these that look very good, and I'm sure I could go larger yet.

I'm sure there are plenty of other uses where it is acceptable... but keep in mind this is only because we already own this lens from our old ASP-C cameras, and it's not worth dropping $1,200 for a good macro lens that we would use for nothing else besides what we already are using the 60mm for.

Re: Why Use A APS-C Lens With Full Frame Camera

Cantrell — Tue, 24 Jun 2025 02:06:28 GMT

Gary,

Thank you for your reply.

Re: Why Use A APS-C Lens With Full Frame Camera

ebiggs1 — Tue, 24 Jun 2025 14:07:56 GMT

"Why would you want to use that combination?"

The oblivious answer is cost. And the number one reason is the person is deciding to switch to R series and they have a good inventory of crop lenses. Even new RF crop lenses are are sometimes less expensive.

Re: Why Use A APS-C Lens With Full Frame Camera

Cantrell — Tue, 24 Jun 2025 15:02:21 GMT

Eb,

Thank you for your response.