Here are the Canon RF 24mm f/1.8 Macro IS STM and Canon RF 15-30mm f/4.5-6.3 IS STM

Jul 21, 2010
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However, the quoted pixel dimension on the various sites I believe is calculated by assuming 44.8 Mpx on 24x36mm sensor. But, Canon quotes 47.1 effective Mpx, which would equate to 4.28µ pixels.
Is the sensor exactly 24x36mm? Or is it slightly larger with the non-effective pixels outside the 24x36mm imaging area?
 
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jd7

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Thanks for your sharing your opinion, no problem there. You're correct, I tend to shoot the 35mm up close for small subjects up to around 30cm in size at f/2 for good bokeh (more like product/food photography scale), and when I shoot wider scenes at medium to far range (nature settings) I'm stopped down to f/5.6 or f/8 for greater depth of field, which is why it works for me, as I don't use it wide open for subject separation on wider scenes where the bokeh would become apparent, such as portraiture.

I've seen too many reviews where the RF 85mm is described as a sharp lens with lots of contrast, with a flat plane of focus like a macro lens, 0.5 macro capability, great for photos of subjects close up, possibly a great product photography lens, but for portraits the bokeh is too contrasty and busy, and not up to par with the bokeh that other 85mm lenses produce stopped down to f/2. Bad for video, doesn't maintain focus well on moving subjects. It has its shortcomings, which is why I didn't buy it.

The RF 50mm f/1.8 is said to be every so slightly better in in most aspects than the old EF 50mm f/1.8, I find mine noticeably sharper stopped down at f/5.6 where it has peak sharpness. It's got decent sharpness at f/2.8, and I stop it down to f/2 when I want balance between bokeh and sharpness. It's not a fancy bokeh lens though.

Totally agree with the huge gulf between these lenses and expensive L versions, as well as the fact that depending on what you use them for, these lenses may not serve your needs at all and be quite disappointing. Personally, I don't think Canon has any decent non-L series portrait lenses, which is really disappointing. I'm definitely not wanting to pay thousands for an RF 85mm f/1.2 L.

In the thread you linked to, there was some very useful information - when the RF 35mm (and other 35mm lenses) are used wide open with the focus point greater than 3m (10') away, and a busy background, such photos don’t play to the 35mm strengths. The fancy EF 35mm II L and Sigma 35mm Art lenses produce a better bokeh in these situations, but not ideal still.

To quote the last post in that thread, which may be helpful, "The best looking bokeh often takes place in a distance sweet spot, especially with 35mm lenses. When you get past 10 feet with this lens you start to see some issues with bokeh in the corners. You almost get this split image that happens and it can give a very distracting nervous feel. So at f1.8 you’ll want to stay within 10 feet (3 meters) for the best looking bokeh.This is pretty standard though. I include this in my reviews now because people will often complain about nervous bokeh, or this bokeh or that bokeh, but the quality of bokeh varies massively with distance on most lenses so this lens will be suited well for head shots, but for full body portraits you will get a distracting bokeh."
And I think your post has identified the difference between your perspective and mine on the lenses. For me, one of the most important uses of a 35mm, 50mm and 85mm is environmental portraiture / portraiture, while portraiture doesn't seem to be a priority for you (at least for the 35mm). So, as much as I like the idea of a small, light 35mm, the RF 35mm f/1.8 isn't the one for me. I am glad it's there for people such as you who will make the most of it, I just wish there were more RF native options. I doubt Canon will give us multiple RF 35mm f/1.8 options though, so I'm betting if I had an RF camera my option would be to look at whatever RF 35mm L lens they come out with, but I assume it will be very expensive and probably large and heavy, so I have doubts it will be the lens I'm looking for either. I really wish we'd start seeing more third party options with AF, particularly from Sigma, Samyang and Tamron, because they may well fill the gaps Canon leaves (assuming there are enough other people out there who have similar preferences to mine).
 
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AlanF

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Is the sensor exactly 24x36mm? Or is it slightly larger with the non-effective pixels outside the 24x36mm imaging area?
We need the info from Canon. The difference is only 2.5%. I should also take into account the pincushion effects of lens distortion, 1.58% for the RF 100-500mm and 1.59% for the EF 100-400mm II fully extended. Allowing for the lens distortion in the calculations assuming 4.39µ pixels gives:
RF 100-400mm @400mm, 405mm
RF 100-500mm @500mm, 509mm.
And for 4.28µ pixels
EF 100-400mm II @400mm, 395mm
RF 100-500mm @500mm, 496mm.
The second set is more credible and so I suppose it is more likely that the sensor actually has the higher figure of pixels in the 24x36mm^2 frame. But, I think the take home message within a couple of percent is that we can all sleep better knowing that Canon has not defrauded us by too many mm of focal length when we are standing some 400,000 km from our subject.
 
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AlanF

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What about at infinity? ;)
I redid the measurements with the RF 100-500mm using the R7 and the latest Supermoon, which is 10% closer than before, so even nearer from infinity but with more pixels. Assuming the frame is 22.3mm wide and filled by 6960 px, I calculate the f at a nominal 500mm to be 492mm.
 
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