Building on this response from AlanF, it might be handy if you ready the Metabones white paper on speed boosters. It's quite informative:
i.e., in effect the lens is wider relative to the physical actuality from the perspective of the sensor.
I think from a standard consumer perspective I'd agree, but if we take the R7 it's pro turf in appropriate contexts. I think in that case bright glass design makes lots of sense, in which case a sealed edition of the 17-55 (or now 15-70) at 2.8 or better would be great just for the normality of the effective perspective range provided that would be much better than simply attaching a copy of the 24-70 or 14-35.
100%
Interesting. I hadn't looked into crop market at all -- once I went full frame I never looked back. As much as I liked the reach of my crop cameras I was never ever satisfied with the noise or the hassle of cleaning it up before sharing anything remotely serious on a family or friends outing at the end of the day around the hotel room or camp site. So, while I miss my reach — I've simply compensated by getting or borrowing or renting longer lenses.
Memories.
100%. Although another lesson I learned mid-way.
I bought it as well. I took it to Japan with R7. I only took this combo and a very good combo. I am going back next month with the same combo. You will enjoy using this fast zoom morning to night. No swappingHow I would have liked a replacement to the 15-85 for my R7 but sorry Canon - too late. I got tired of waiting and just three days ago picked up a Sigma 17-40 f1.8.
Yeah I know it's only 40mm at the long end but I've got it and I won't be stuffing around selling it and purchasing another lens.
But never say never I guess
It is the exit pupil that determines the image circle. The important points that were in in my reply are: that the image circles from the longer telephotos are so large that an APS-C or smaller sensor lenses cannot be made significantly smaller than those for full frame - indeed the lens often has to be baffled to stop the light outside the sensor from bouncing onto the sensor; for wide angle lenses the smaller the sensor the easier it is to make complex lenses to enlarge the circle to cover the sensor - it is cheaper and easier to make a light wide angle lens for crop, however, this is offset to various degrees by needing a wider angle lens to give the same field of view.
Can you provide an example?
I find that the concept of equivalence is not at all useful. When taking an image with an R7 and a Sigma 18-50, I don't calculate the equivalent FF focal length and DOF. I just zoom the lens and use the DOF of the lens that I'm using and it works. One consequence is that I shoot wide open or nearly so most of the time.
It is really important when comparing cameras with non-standard image sensor sizes.
The absence of the 17-70 does indeed make more sense now, that was Tamron’s only mirrorless APS-C lens that didn’t directly compete against a superior Sigma alternative on RF mount, and one that would’ve been popular with the RF-S bodies lacking IBIS (4/5 currently).
Ok. The fact that you personally don’t find it useful does not mean the concept is inaccurate, nor does it mean it’s not applicable to photography. It is both.
Of course not, that’s not the point of equivalence. If you were considering replacing that R7 with a full frame or m4/3 camera, the concept of equivalence could help you decide which lens you should buy to enable you to keep taking pictures like the ones you currently take.
I'm not sure if you are just being stubborn, or you remain utterly confused about the concept (willfully, because you haven't read the links previously posted, or because you've read them and remain unable to understand the concept). It's not about "FoV equivalence' or 'DoF equivalence' or 'noise equivalence' – it's about image equivalence. FoV, DoF and noise are all characteristics of an image… and they are all affected by sensor size.
So in your world view, incorrect statements should not be challenged or corrected? Or if they are, no explanation should be provided?
I agree in the sense of practice in the field: it's not too useful unless you're shooting each format side by side and need to synchronize effect. I only tend to use one or the other (my own camera is FF at this point, but my kiddo has an 80D) — but even then, it's almost like speaking different languages: unless you need to switch mid-sentance, you're thinking and doing in language A or language B but not a mix. You simply figure out what lenses achieve on your format and run with it.
I own an R6-2 and an R7 and have several lenses for each. Most of my FF lenses are EF and most of the APS-C lenses are RF. Sometimes I will go out with both bodies on a Black Rapid double harness. Typically, the longer lens is on the R7 and the shorter lens is on the R6-2, for example EF 24-105 f/4 and EF 16-35 f/4 or EF 70-200 f/4 and EF 24-105 f/4. My big complaint, the one that triggered my rant, is with DOF equivalence. As far as I'm concerned, it's a marginally useless concept, especially when trying to actually capture an image.Here's a really nice article that walks through an example of image equivalence:
“Equivalence” in a Nutshell | Sans Mirror | Thom Hogan
Equivalence in camera systemswww.sansmirror.com
If you're purchasing a mixture of gear, or if you're purchasing gear and want to recreate what someone else has done with different gear, or if you're in the field with different formats and attempting to achieve the same effect then this is good stuff to know.
If you have one camera and you're doing your own thing, keep calm and carry on...
Exactly, and who does that, right? But again, as I think you understand, that’s not the point of the concept. The utility is here, where we’re pressing keyboard keys and not shutter buttons, on CR and other settings where photography is discussed.
