Dragon said:

When you say "Sony limits the AF speed", is that a diabolical move on Sony's part or is the Sony system simply incapable of providing enough current to run the AF at full speed? I suspect that more often than not, the issues we discuss as if they were marketing decisions are actually engineering limitations. Much the same as the Canon "cripple hammer". A budget was set for a product, and engineering may well have done the best they could with that budget. We may not like the choice of tradeoffs, but the decisions may well have been as much or more engineering decisions as they were marketing decisions.

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The way it was presented was that Sony cut the AF speed and max frame rate for the Sigma lens (diabolical), keeping peak performance restricted to their GM lenses. Although, it may be in the secret sauce and Sigma has to backwards engineer it like with Canon, and they just couldn’t optimize for the Sony mount,, what the lens is capable of, like they can for Panasonic. With Sigma, Panasonic and Leica making up the L alliance, presumably Panasonic shares the recipe with Sigma, so the Lumix can take maximum benefit of the lens. Or as you suggested, provide the necessary juice with their batteries to drive the AF on the Lumix, like the new batteries required to take full advantage of the R5 II.

I like the idea of a 300-600 f4 in Africa or on the Amazon, especially on a 40-50 MP sensor. Apparently the AF is quicker on the Lumix S1 II, than the S1R II, so that was my reservation with limitation of 24 MP on the S1 II. My thought is by the time Lumix releases the S1R III, the AF and pre capture will be fast enough that I am the rate limiting step, not the camera, that’s where I think I am at with the R1 and R5 II.

The folks I was with, were shooting Sony A1 or A9, or Nikon Z8 or Z9, the Canon guys were shooting the R1 and R5 II. They were all doing better than me with the R3 and R5, particularly on the Amazon, small targets at a distance, locking AF was markedly better on my roommate’s R5 II.

I had just gotten the R5 II, but hadn’t used it, and prior experience heavily suggested that the first time shooting a camera is best not reserved for a trip, no muscle memory and searching the menu, because it is not like your other Canon results in a lots of missed shots for me. I love the R3, but the improved AF in the R1 and R5 II, and pre capture are game changers for wildlife as far as I am concerned. That’s why I want an R7 II, one of the prints from Africa that I printed for my living room went below the 300 dpi once I went above 24” x 36” and it’s on a wall were you can walk right up to it, so people aren’t standing the “proper” distance were everyone says 24MP is enough. I was interested in the rumored R3 II, which I was hoping would have more MP’s than the R3, and obviously the improved AF and pre capture. I got the R1 with Canon’s last trade-in opportunity, but haven’t used it yet, 2026 is all underwater for me with the R7.

Sigma lenses I'd want to see on RF mount

- 35mm f/1.2
- 15mm f/1.4
- 28mm f/1.4
- 135mm f/1.4 (I'd get this)
- 28-45mm f/1.8

Ran across this one in my archive. I've seen many GBHs, but not very many GBH tongues.

"Say Ahhhhhh"

EOS 1D X, EF 600mm f/4L IS II USM, 1/2500 s, f/10, ISO 8000

Great shots, ISv. I especially like the first one.

Sigma should also produce a few tiers of microphones, on-camera flashes, and dual chargers for Canon users alongside their lenses. Canon might even consider selling the R5 Mark III or R7 Mark III without accessories altogether. Maybe Sigma can finally free us from that thing called “Picture Style.”

jeff89 said:

I like many would buy the Sigma 300-600 f4 and personally, the Sigma 135 f1.4 Art (I have the EF 135, RF 135 and Sigma EF 135 Art) and would pair it with my Sigma EF 105.

I wouldn't pay Canon's price for the RF 100-300 f2.8 before the tariff increase, as I have the Sigma EF 120-300 2.8 and I won't pay for the Canon RF 300-600 f???, as is would be a want and not a need. I have 2 of the EF 200-400 f4 1.4x, the EF 300 f2.8 and the EF 400 f4 DO and I refuse to pay over $11,000 for a lens, but at $6599 for the Sigma, I would buy that, provided it integrates well. Sony limits the AF speed on it, so I won't buy the Sony version. In fact, I was seriously considering the Lumix S1 II, or maybe the S1R II given the alliance and the fact that it is optimized for the Lumix.

I will hold off for now, to see if they release it for the RF mount, if it doesn't happen, then I will buy a Lumix down the line and begrudge Canon for it.

Oh, and I know a retired Canon USA exec, I never asked for any scoops, I didn't think it was appropriate, but was told, "Pay attention to Canon Rumors." So you might have more pull than you know

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When you say "Sony limits the AF speed", is that a diabolical move on Sony's part or is the Sony system simply incapable of providing enough current to run the AF at full speed? I suspect that more often than not, the issues we discuss as if they were marketing decisions are actually engineering limitations. Much the same as the Canon "cripple hammer". A budget was set for a product, and engineering may well have done the best they could with that budget. We may not like the choice of tradeoffs, but the decisions may well have been as much or more engineering decisions as they were marketing decisions.

I don't know if @foda has success with the Orange-cheeked Waxbill but today I didn't (~40 min. searching). Took just few photos of House finch (two different males separable not only by the color: different amounts of dirt on the bill ! They did choose the same broken branch for posing. I still have no photo of House finch with yellow instead of orange/red colors on the head, despite seen few!

This is what shows up on my R1 with lens that forces distortion correction attached (not as obvious in the iPhone pic, but the Distortion correction option is grayed out):

AlanF said:

A Little Grebe was trying to swallow a fish that was too large. It bit off its head, a gull swooped to steal the fish, and the Grebe dived faster than a U-boat (R5ii + RF 200-800mm).

View attachment 228683View attachment 228684View attachment 228685

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Nice photos/story with happy ending . I don't like the gulls when they behave like kleptoparasites! On other hand I have a lot of fun watching videos of them stilling from people on the beech

I like many would buy the Sigma 300-600 f4 and personally, the Sigma 135 f1.4 Art (I have the EF 135, RF 135 and Sigma EF 135 Art) and would pair it with my Sigma EF 105.

I wouldn't pay Canon's price for the RF 100-300 f2.8 before the tariff increase, as I have the Sigma EF 120-300 2.8 and I won't pay for the Canon RF 300-600 f???, as is would be a want and not a need. I have 2 of the EF 200-400 f4 1.4x, the EF 300 f2.8 and the EF 400 f4 DO and I refuse to pay over $11,000 for a lens, but at $6599 for the Sigma, I would buy that, provided it integrates well. Sony limits the AF speed on it, so I won't buy the Sony version. In fact, I was seriously considering the Lumix S1 II, or maybe the S1R II given the alliance and the fact that it is optimized for the Lumix.

I will hold off for now, to see if they release it for the RF mount, if it doesn't happen, then I will buy a Lumix down the line and begrudge Canon for it.

Oh, and I know a retired Canon USA exec, I never asked for any scoops, I didn't think it was appropriate, but was told, "Pay attention to Canon Rumors." So you might have more pull than you know

​

P-visie said:

When I visited the Isle of May with a small group of photographers, a tern shat on the front of the lens and the inside of the lenshood of one of the groups members. He had a hard time cleaning the lens and the black velvet of the lenshood. It was a Nikon, the terns did not dare shizzle on a Canon.

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Do not challenge the terns...

zapper said:

My Sigma RF-S 10-18 f2.8 and 18-50 f2.8, when mounted on my R7, show "Not available with the attached lens" for distortion correction, and "Cannot correct - no data" for Digital Lens Optimizer, in the Lens aberration correction menu. This doesn't bother me much, as I shoot raw and process in Lightroom, which does apply the corrections.

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My Sigma 17-40 also shows "not available" for distortion correction, however if you compare the RAW with an OOC JPEG you'll see massive distortion at 17mm being straightened, so this seems to be more of an “always on" situation, as with the RF-S 18-45.

Out of curiosity, is it known whether “Canon allows…” means official support such that the lenses will be forward compatible like Canon’s EF or RF lenses or does it mean Sigma & co. need to guess and Canon simply won’t sue them?

I'm still scratching my head.
1) Sigma already has spent the R&D money to develop full-frame lenses like 300-600/4
2) Sigma already has spent the R&D money to figure out the RF mount, as evidenced with their RF-S lenses.

So why aren't they putting 1 and 2 together? I don't see this being a Sigma issue. It seems logical the issue lies elsewhere.

I would gladly buy the Sigma 300-600mm if they released it in either EF or RF mounts.

Ron888 said:

Has no one noticed what day it is? lol

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True, but the relevant conversation with the Canon exec was reported well before April 1, so the article is legit.

zapper said:

My Sigma RF-S 10-18 f2.8 and 18-50 f2.8, when mounted on my R7, show "Not available with the attached lens" for distortion correction, and "Cannot correct - no data" for Digital Lens Optimizer, in the Lens aberration correction menu. This doesn't bother me much, as I shoot raw and process in Lightroom, which does apply the corrections.

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I think that answers my question. Unless the lens is relatively distortion free, that missing bit, while not much of an issue for a RAW still shooter, is a big deal for video. Simply due to lens size implications, this would be a bigger issue for FF lenses than for APS-c. A number of Sigma's EF lenses were quite good, and relatively distortion free, they were also big and heavy. Given that Canon is taking full advantage of electronic correction, that gives them both a size and cost advantage over a third party that is obliged to do all correction optically due to lack of access to the electronic correction capabilities of the camera. As an aside, I have a fair number of 3rd party EF lenses that will not work correctly on either RF or EOS-M mount cameras and all my Canon EF lenses work normally on both mounts, so even the EF protocol had some undiscovered features that the 3rd parties didn't catch and now have no interest in fixing. DPAF definitely messed with the AF algorithms that both Sigma and Tamron were using. FD lenses work fine on RF .

Has no one noticed what day it is? lol

Dragon said:

So a question. The RF mount clearly provides for extensive geometric correction (and I believe even includes correction for focus shift) in-camera and the data to support that correction clearly resides in the lens, since I don't have to upgrade my camera firmware every time Canon comes out with a new lens. The question is, do the Sigma and Tamron APS-c lenses supply that correction info the camera or just depend on being good enough optically to not perceivably need in-camera correction.? Lack of that tech would be a much bigger deal for FF than for APS-c. It is pretty clear that Even Canon has not yet exercised all the features of RF mount, so until there is a very large body of Canon bodies and lenses to evaluate, it would be very risky for 3rd parties to release lenses that could be rendered obsolete with the next camera release.

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My Sigma RF-S 10-18 f2.8 and 18-50 f2.8, when mounted on my R7, show "Not available with the attached lens" for distortion correction, and "Cannot correct - no data" for Digital Lens Optimizer, in the Lens aberration correction menu. This doesn't bother me much, as I shoot raw and process in Lightroom, which does apply the corrections.

Canon Rumors said:

"Ported" and being able to actually make enough are different things. A lens like the 135 f/1.4 would be a very difficult lens to make within tight tolerances. Sigma made nothing worth owning for most of the EF days. When they did start making things that were sort of nice there were already 100+ million EF lenses. Having worked directly with Gentec, I know how few lenses they sold in the grand scheme in at least one market (maybe 2). It was peanuts.

Demand increasing 30% is great, now you have to scale everything else 30%. There's a point in lots of businesses where the next step costs exponentially more than the previous one.

Take a company like Leica (yes, they do it different). They make 40 cameras a day. Major products usually take about a year to meet the demand. How much would it cost them to increase production to 60 a day? A boatload. Sigma is closer to Leica than they are to Canon. Leica's revenue is actually higher than Sigma's.

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Sorry, I have the completely opposite opinion.
Why should Sigma (or any other 3rd party lens manufacturer) be 'required' to make enough RF lenses to fulfill a very high demand in short time?
Sigma would simply sell as many lenses as they can make, be very happy with the revenue, and later they can decide to increase production capacity if the demand justifies it.

In a free market, any supplier can offer as many product units as he wants, while there is no obligation to produce a very large quantity, even if an initial short supply might disappoint some prospective buyers. After a while production capacities will adjust to the demand.

Additionally, all RF and RF-S cameras use the same RF mount, only the image circle of an RF-S (APS-C) lens is smaller than FF.
Consequently, there is no additional 'technical difficulty' to overcome or any 'reverse engineering' needed for FF RF compared to APS-C RF-S. Note that there are already several 3rd party autofocus RF-S lenses available, e.g. Sigma 15mm f/1.4 DC, so 3rd party manufacturers have already solved the 'technical difficulty'.

I did some searching for lens sales numbers. An estimate for Sigma is ~1 million/year, across all mounts, including legacy DSLR. For Canon, ~7 million/year. So your hypothesis that Sigma's production capacity is a limiting factor seems plausible. In that scenario, the Sigma RF-S lenses make sense, as Sigma stands to sell many without competition from Canon. I've two of their RF-S lens, including the 18-50mm f/2.8, but I wouldn't have bought it if Canon had an APS-C 16-50mm f/2.8 as Nikon does.

I am onboard for a
200-400 f4 no built in converter
2nd place a 100-500 5.6 constant aperture.
3rd place their 300-600 f4, a bit overkill for NHL but would be good for football and soccer!

justaCanonuser said:

nice frog in the green, but it looks like sharpness isn't exactly on the frog's eye, so the camera's AF struggled a bit

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Yes, that was subsequently corrected with AFMA.

So a question. The RF mount clearly provides for extensive geometric correction (and I believe even includes correction for focus shift) in-camera and the data to support that correction clearly resides in the lens, since I don't have to upgrade my camera firmware every time Canon comes out with a new lens. The question is, do the Sigma and Tamron APS-c lenses supply that correction info the camera or just depend on being good enough optically to not perceivably need in-camera correction.? Lack of that tech would be a much bigger deal for FF than for APS-c. It is pretty clear that Even Canon has not yet exercised all the features of RF mount, so until there is a very large body of Canon bodies and lenses to evaluate, it would be very risky for 3rd parties to release lenses that could be rendered obsolete with the next camera release.

I think most of the folks complaining have been assuming that a licensing deal includes access to the technology and the comments you refer to clearly refute that. That said, figuring out the protocol may be much harder that some think, since the communications could well be encrypted. That pin that switches back to EF protocol may be more complex than many think. It is notable that the folks who got shut down (Samyang, et al) were simply using EF protocol with an RF mount and Canon would have been perfectly justified in zapping them for misrepresentation.

Kingsix88 said:

If I remember correctly, when Canon first came out with the RF mount, these was something strange with the image on third party lens. Unexpectedly strong vignetting and purple hue. I believe it has something to do with canon sensor technology and mirrorless cameras having much shorter distance between rear element and sensor. So light rays hit the sensor at much sharper angle, compared to dslr. Sony didn’t have that issue. It is possible canon mount requires different lens design in certain focal lengths for adequate performance. This is not worth it for a third party lens manufacturer to do. Maybe crop doesn’t have the same issue.

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I don’t think so. When the RF mount first came out, there were no third-party lenses for it. That is a recent development, and only for crop lenses.

What you are referring to are issues with peripheral image correction on third-party EF lenses, those were caused by the camera incorrectly identifying the lens. Such lenses spoof Canon lens ID numbers, and the RF mount made that problematic.

Since those were EF lenses, they required the mount adapter, and thus the distance from the lens to the sensor was the same as that on a DSLR. Optics was not the problem, electronics/software was the issue.