Sigma officially launches the RF 18-50mm f/2.8 DC DN Contemporary

This highlights what the photography industry is really missing: IP rating numbers, or a new scheme for equipment.

My iPhone has an IP rating of 68, but my camera? Crickets.
Only one ILC has a IP rating as far as I know and that is the OM-1 with IP53 ('5' represents a very high level of dust resistance (6 would be completely dust-proof), and the '3' indicates that the camera can withstand at least three minutes of water being sprayed at a 60 degree angle)
Petapixel showed some video of the testing
https://petapixel.com/2022/05/27/how-om-digital-torture-tests-its-weatherproof-cameras/

Frankly, IP ratings are very hard to achieve consistently with moveable rings, interchangeable mounts with buttons etc.
Would they make a difference to the normal buyer?
Your iPhone's IP68 rating = water resistant in fresh water to a maximum depth of 1.5 metres for up to 30 minutes. The "depth" is a constant pressure but there is an active (higher) pressure with movement. The act of quickly pulling up your phone from 1.5m would exceed the rating for instance... best to gently waft it upwards over time :)
In any case, phones are sealed with few moving parts. Very different with ILC systems.

If users are serious about protection then underwater housings are the only option for ILCs. And even then, you need to check O ring using a vacuum pump.
I've never had a flood in 15 years with different housings yet my wife's gopro had a problem at snorkeling depth! We'll never use it underwater again without a housing now.
 
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As I mentioned above, the Nikon 1 AW1 had an IP68 rating for 15 m, could be used for snorkeling.
Ah, I hadn't seen your post before I replied... The AW1 looked interesting - when it worked :)
https://photographylife.com/reviews/nikon-1-aw1
Adding a housing basically doubles the body cost (or more) so a fixed lens is a cheaper solution eg TG7.
Given what the phones can do now and their IP rating, there isn't really a market for low cost underwater cameras any more and the housings for them are pretty good too.
 
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Interesting….. This could be the lens I've been waiting for to replace my ageing EF-S 17-55. There are rumours of a Canon RF-S lens around this focal length and aperture. If it's true it would probably have a bit more range and include IS, but will be 3 times the price. If Canon have given approval and included data for this lens, I wonder if they have abandoned their own version? They don't usually support APS-C with any high quality lenses. Does anyone know if the lens mount is metal or (more likely) plastic?
 
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Frankly, IP ratings are very hard to achieve consistently with moveable rings, interchangeable mounts with buttons etc.

I can imagine. I am ambivalent as to what mechanism Canikony use, but I think it is well past the time that they introduced something.

If Yongnou started making claims about this, whilst doing nothing to make it possible, what would a tester do to debunk such claims?


Would they make a difference to the normal buyer?

If it makes no difference to buyers then why does this "feature" get written about in product advertising,etc?
 
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Granted there are different design considerations that need to be taken into consideration when coming up with a rating scale and set of tests to verify the claims. If Canikony group want to use the IP scale or come up with something new, I don't care. Including if they have a list of caveats.

But they need to move on from making hand waving claims about weather resistant or whatever to something that is both measurable and testable. This might include, for example, having the plastic plug in the lens mount fitted, or with specific lenses.
CIPA should just come out with a standard.
I can understand if they do not all want to conform to the IP rating.
Although, the IP rating would be helpful when comparing camera gear to other things.
 
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Great to see Sigma starting with RF-s lenses. The lens might be tempting, if I decide to get a R50 as a lightweight option for hiking and such.

To me, it´s kind of weird that the product images show the lens attached to the R5. Wouldn't it make more sense to use the R7/10/ 50?

Constant F2.8 aperture, 300g and weather sealing sounds great :)

From the looks of it, the only downside is that it doesn't have a control ring. Since the R50 only has one dial (if I remember correctly) this actually could be an issue for me one day...
Marketing fotos. Much to do about marketing fotos these days. People reading more into them than should be expected. Same for the Panasonic marketing fotos. They use whatever is given to them with the product or for the product. Nothing more than that. What body its on is not important. Same as commercials depicting products used in unrealistic ways they will never be used.
 
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CIPA should just come out with a standard.
I can understand if they do not all want to conform to the IP rating.
Although, the IP rating would be helpful when comparing camera gear to other things.
A good start would be for manufacturers to support water damage warranty claims, pretty much every company except OM-systems refuses to cover it.
 
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... But TBH, I don't see very much about this lens that's compelling to me personally.

By comparison, the Canon RF-S 18-150 has:
- Same size
- Same weight
- 3x the zoom range
- Image stabilization

The obvious advantage of the Sigma is speed and constant aperture; the Canon starts at f/3.5 and is already at 5.6 at 50mm, a 2-stop difference from the Sigma.
...
Are you really trying to compare apples with oranges?

I understand that a zoom with higher zoom factor is YOUR tool of choice.
And that is okay. It always depends on the use case.

But I think it is clear that Sigma is trying to deliver a different offering (obviously not yours):
A wide aperture (f/2.8) but still compact universal standard zoom for APS-C.

If you prefer the RF-S 18-150, that's fine and one (your) way to go.
Others will choose different.

If you want to compare the Sigma 18-50mm F2.8 DC DN with anything from Canon, your only obvious choice should be the EF-S 17-55mm f/2.8 IS USM (+EF to RF adapter).

Here (without any field comparisons IQ available):
  • the EF-S has a plus for a wider zoom range (1 mm at the wide and 5 mm at the tele end, really important for some!)
  • the Sigma has plusses at almost any other spec data (size, weight, native RF-S mount, +in-camera aberration correction for third party lens, etc.)
  • e.g. length only 57%, weight only 40% of the EF-S (+EF to RF adapter)
  • thinking about how old the EF-S optical design and coating technology is, I would go out on a limb and say that the Sigma will be optically better
Better comparison needed?
 
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No, per the press release, Sigma is calling it the "SIGMA 18-50mm F2.8 DC DN |Contemporary for the Canon RF Mount System."

The CR headline calls it the "RF 18-50mm f/2.8 DC DN Contemporary", but that's not from Sigma.
Good point. I've forwarded this to CR stuff. Hopefully, they change the thread title.
 
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Are you really trying to compare apples with oranges?

I understand that a zoom with higher zoom factor is YOUR tool of choice.
And that is okay. It always depends on the use case.

But I think it is clear that Sigma is trying to deliver a different offering (obviously not yours):
A wide aperture (f/2.8) but still compact universal standard zoom for APS-C.

If you prefer the RF-S 18-150, that's fine and one (your) way to go.
Others will choose different.

If you want to compare the Sigma 18-50mm F2.8 DC DN with anything from Canon, your only obvious choice should be the EF-S 17-55mm f/2.8 IS USM (+EF to RF adapter).

Here (without any field comparisons IQ available):
  • the EF-S has a plus for a wider zoom range (1 mm at the wide and 5 mm at the tele end, really important for some!)
  • the Sigma has plusses at almost any other spec data (size, weight, native RF-S mount, +in-camera aberration correction for third party lens, etc.)
  • e.g. lenght only 57%, weight only 40% of the EF-S (+EF to RF adapter)
  • thinking about how old the EF-S optical design and coating technology is, I would go out on a limb and say that the Sigma will be optically better
Better comparison needed?
I don't disagree. I was very deliberate in my original post to say "to me personally." I know many people prefer a wide, constant aperture, and I see the value in that, but it's not my priority. I rarely shoot with this range anyway, so if I'm going to carry it "just in case", a wider zoom range in the same size/weight package is usually preferable, even with two stops less light. But, again, that's me. I learned photography back in the days of "f/8 and be there", so I rarely shoot wide open anyway. Old habits...
 
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CIPA should just come out with a standard.
I can understand if they do not all want to conform to the IP rating.
Although, the IP rating would be helpful when comparing camera gear to other things.
I wouldn't dunk thousands of dollars of gear into a lake based on a CIPA rating. CIPA is a marketing organization. If they were to come out with this sort of rating, it would likely have opaque test methods and be designed to make their member manufacturers look good.
 
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CIPA should just come out with a standard.
I can understand if they do not all want to conform to the IP rating.
Although, the IP rating would be helpful when comparing camera gear to other things.
I can't imagine CIPA coming out with a separate (competing?) standard than IP ratings. It would just cause some confusion for why and unless they get significant pressure from the OEMs. I can't imagine Sony/Canon/Nikon etc wanting to subject their gear to more independent testing before shipping not to mention the reviewers commenting on it.

There is no way that any ILC manufacturer will accept warranty claims on water ingress (especially salt water) if there was the claim that L lenses (with rubber on the mount) were covered but non-L lenses weren't. Given that my global insurance is ~4% of replacement cost, it would be cheaper for me than Canon increasing their costs to provide a IP rating.

Canon has released drawings in the past showing how good the sealing is on the higher end bodies but there is no incentive for the lower end.
Similarly for their lenses although they should promote the RF engineering more like Roger used to do. That means a lot more to me personally but still only generalisations vs other competing equivalent lenses. It was particularly important countering the assumptions of internal vs external zoom. I liked the comment that all lenses get dust and some of the worst were prime lenses :)
 
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I can imagine. I am ambivalent as to what mechanism Canikony use, but I think it is well past the time that they introduced something.
If Yongnou started making claims about this, whilst doing nothing to make it possible, what would a tester do to debunk such claims?
If it makes no difference to buyers then why does this "feature" get written about in product advertising,etc?
I am trying to understand what the incentive is for OEMs to do this. It would only add cost and not necessarily improve their revenues or margins.

Apple does it to differentiate them in a market where little differentiates the top models besides cameras. More likely for a phone user to drop theirs in the toilet than Canon but it is unclear whether the "fresh" water IP rating would apply in that case!

Oly (with one model) has a IP rating and it is a great way to convince higher end / more abusive users that the OM-1 competes with the Z9/R3 etc but they haven't sold enough to move their market share needle.

Canon/Nikon have decades of engineering and on-the-ground testing of ruggedness (however you want to phrase it).
Everyone knows about the battery door water ingress issues of the A7iii and earlier models so Sony have some time before they get to the same reputation as Canon/Nikon.
It wouldn't take long for Canon to get a bad rep if their R3/R1/R5 model report issues though.

Plenty of photos of broken lenses out there after users dropping them but when you have a combination of bodies and lenses (including 3rd parties) then IP ratings won't help.
 
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Similarly for their lenses although they should promote the RF engineering more like Roger used to do. … It was particularly important countering the assumptions of internal vs external zoom. I liked the comment that all lenses get dust and some of the worst were prime lenses :)
That highlights the difference between Internet forum ‘experts’ and people with real, relevant knowledge.
 
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For photograpy, probably it's better the Canon 17-55 F2.8 with EF-RF adapter.
I've been using the EF-S 17-55 on my R7 for ages now. I used the same lens with my 40D and 7Dii, but with the adaptor it makes it ungainly. It's funny how 20mm makes so much difference. It works but the balance was better with the old DSLR's which were also heavier. A benefit of a new lens would be improved focussing speed with the new cameras, and probably a little bit smoother zooming (I believe a power zoom is rumoured). So, buy this or wait for Canon ….and wait ….and wait….
 
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