The first review of the Canon RF 10-20mm f/4L IS STM is here

[neuroanatomist]

"I do keep a B+W clear filter on lenses (except the really cheap ones)"
You pay more than $2500.- for a premium lense to get the best possible sharpness and than you mount a clear glas filter to protect the front lense? The front lense is proteced enought if you mount the lense hood. I don't understand this kind of care understanding. Just keep care - that's is protection enought. If not, you should change your handling.

Very much a to-each-their-own thing. I have personally tested the effects of using a filter on sharpness, and except for strongly backlit conditions there is no meaningful loss of IQ from a good quality filter. OTOH, I don't baby my lenses...they are tools, not trophies. I change lenses and put the removed one back in the bag without (I know, GASP) putting the lens cap back on. The filters routinely get dust, water, dirt (and occasionally fingerprints) on them...and I'd far rather risk scratching an $80 filter with a hurried wiping of the front than scratching the front element of a $2500 lens.

Also, while the hoods for telephoto lenses provide good protection, hoods for lenses that include wide angle focal lengths don't. There's a lot of exposed front element on my 24-105/2.8 even with the hood mounted.

 

[YuengLinger]

"I do keep a B+W clear filter on lenses (except the really cheap ones)"
You pay more than $2500.- for a premium lense to get the best possible sharpness and than you mount a clear glas filter to protect the front lense? The front lense is proteced enought if you mount the lense hood. I don't understand this kind of care understanding. Just keep care - that's is protection enought. If not, you should change your handling.

I like the idea of photographers, experienced and otherwise, deciding for themselves. Open minds, live and let live, each accepting compromises as they see fit.

Personally, I always use a high quality filter unless I know I'm going into a strongly backlit situation. And even when I do use against bright sunlight, seriously, the impact on IQ, the issues with flare, are rarely noticeable. So, if out on the beach on a windy day, even with backlighting, yep, I'm keeping the filter on.

I've had the filters save the front element from nicks and scratches, but the main reason I use them, just as neuroanatomist says, is to avoid cleaning the front element. When grease and grime inevitably get on there, rather than stress the front element coatings, I'm simply cleaning an easily replaceable filter.

But why is this even controversial? And why is it part of a thread about a lens THAT CAN'T TAKE A FRONT FILTER? Why should I care if your element gets scratched, or why should you care if I'm losing 1% image quality from images that are still 1000% better than from digital cameras 20 years ago?

By the way, I've tried reproducing some of the youtubers' tests showing loss of sharpness, especially one guy who is a bird enthusiast, and my results show insignificant losses--not anywhere near what the click-hungry influencers claim. Ymmv.

 

[john1970]

Very much a to-each-their-own thing. I have personally tested the effects of using a filter on sharpness, and except for strongly backlit conditions there is no meaningful loss of IQ from a good quality filter. OTOH, I don't baby my lenses...they are tools, not trophies. I change lenses and put the removed one back in the bag without (I know, GASP) putting the lens cap back on. The filters routinely get dust, water, dirt (and occasionally fingerprints) on them...and I'd far rather risk scratching an $80 filter with a hurried wiping of the front than scratching the front element of a $2500 lens.

Also, while the hoods for telephoto lenses provide good protection, hoods for lenses that include wide angle focal lengths don't. There's a lot of exposed front element on my 24-105/2.8 even with the hood mounted.


View attachment 214972

All very good points. Personally, I use B+W clear filters on all of my L-series lenses unless it is not possible (e.g. RF 10-20 mm and RF 400 mm f2.8). In the past I have scratched a front element on a large telephoto lens and the cost of the replacement was $1000.

 

[Del Paso]

All very good points. Personally, I use B+W clear filters on all of my L-series lenses unless it is not possible (e.g. RF 10-20 mm and RF 400 mm f2.8). In the past I have scratched a front element on a large telephoto lens and the cost of the replacement was $1000.

Which means for me: Even if large filters are expensive, it makes sense using them. (RF100-300 !!!).
I don't want to imagine the cost of its front lens replacement. Certainly far more than $250 for a B&W high-grade clear filter.
Personally, I use filters only on exposed front lenses, the ones flush with the mount. And also specifically when, due to the size of the lens, I have to remove the shade when putting the lens back into the bag. That's when scratches are likely to occur.

 

[EricN]

Which means for me: Even if large filters are expensive, it makes sense using them. (RF100-300 !!!).
I don't want to imagine the cost of its front lens replacement. Certainly far more than $250 for a B&W high-grade clear filter.
Personally, I use filters only on exposed front lenses, the ones flush with the mount. And also specifically when, due to the size of the lens, I have to remove the shade when putting the lens back into the bag. That's when scratches are likely to occur.

Today, I had a big scare. In a hurry, I thought my bag was zipped up, but I was wrong and our fell my rf85 f/1.2. Miraculously, only the protective filter was cracked and some of the lens's plastic scuffed. Do you think if it was the old style metal it'd be dented? Anyway, Auto focus works as normal.

 

[josephandrews222]

Today, I had a big scare. In a hurry, I thought my bag was zipped up, but I was wrong and our fell my rf85 f/1.2. Miraculously, only the protective filter was cracked and some of the lens's plastic scuffed. Do you think if it was the old style metal it'd be dented? Anyway, Auto focus works as normal.

What I think I know, based on both experience and education... is that the engineered plastics used by most lens manufacturers are far more resistant to 'failure' than expected.

What matters (some) is a given material's ability to absorb/dissipate energy, in terms of protecting what's inside during/after the drop (in this case, the sensitive innards of the lens).

What matters a lot are the characteristics and properties of the surface that the lens has fallen onto--obviously a soft landing is better as far as retaining lens integrity and functions are concerned.

I cannot tell, from your post, how serious the drop actually was. But only a cracked filter and scuffed plastic?! Seems like you're good to go.

Point me in the direction of some of your best images with this lens... I'd like to see them.

 

[danfaz]

Today, I had a big scare. In a hurry, I thought my bag was zipped up, but I was wrong and our fell my rf85 f/1.2. Miraculously, only the protective filter was cracked and some of the lens's plastic scuffed. Do you think if it was the old style metal it'd be dented? Anyway, Auto focus works as normal.

The RF 85 has added shock protection for "turbulent situations." I bet it's perfectly fine!

 

[EricN]

The RF 85 has added shock protection for "turbulent situations." I bet it's perfectly fine!

I was worried, but as you said, it's perfectly fine. One funny thing is when I was inspecting it (with my heart racing), the aperture blades had closed quite tightly and I thought it would be funny if they were stuck like that... the new 85mm f/11!

 

[Del Paso]

Today, I had a big scare. In a hurry, I thought my bag was zipped up, but I was wrong and our fell my rf85 f/1.2. Miraculously, only the protective filter was cracked and some of the lens's plastic scuffed. Do you think if it was the old style metal it'd be dented? Anyway, Auto focus works as normal.

You shouldn't have posted this!
It reminds me of the sad horrific day in Wales when I did the same. I dropped my 24 TSE on concrete, fortunately protected by two filter rings. (I had removed the glass off two cheap filters, only to protect the lens' filter thread, in case...). The case happened.
The filter thread remained safe, not so the small inner lens group, the one you see from the rear. It was no longer aligned, but fully slanted.
Long story short: $900...

 

[koenkooi]

[...] It was no longer aligned, but fully slanted.[...]

World's first tilt/shift/slant lens!

 

[Del Paso]

"Do you think if it was the old style metal it'd be dented?"
One cannot generalize here, it all depends on how thick metal is. I've sometimes dropped Leica R lenses, never had more damage than the odd scratch. But if metal rings are of the "tin-foil hat type", damage will be far more serious.
Same for plastics, it depends on the plastic used, its thickness and where the impact occurs. Fiber reinforced plastics have a huge advantage on metal, they yeald upon impact. Also, for optical precision, plastic lenses' inner life is made of metal, for more precision when centering/positioning lenses. I once tried to destroy a Makita battery charger with a heavy hammer, for "fun". The charger had been damaged by a molten 3rd. party battery... It was extremely hard to break the poycarbonate (?) housing.
Frankly: I prefer smaller Canon lenses to be made of plastics, big whites, for stability under high temperatures, to be made of metal. In any case, I'm confident Canon's choices will be the right ones.

 

[Del Paso]

World's first tilt/shift/slant lens!

How can you make fun of my despair?

 

[neuroanatomist]

You shouldn't have posted this!
It reminds me of the sad horrific day in Wales when I did the same.

I’ve had two drops. The first was my 5DII, which was being carried via a BlackRapid strap connected to the foot of my 70-200/2.8 II with the 2x TC, and the balance was altered to the point that the lens release was pressed by my belt. A meter fall onto pavement, the result was a small scuff on the body and all my lens-specific AFMA values shifted by –10.

The second drop was the aforementioned 70-200/2.8 II. Maybe the lens was bad luck? It was a bit over two years ago, ironically when I was taking pics of the lens to sell on Craigslist, just after getting the RF 70-200/2.8. I failed to carefully clamp the edge of the infinity board, and it rolled up and knocked the lens off the table to the tile floor. The lens functioned fine and IQ was unaffected, the only damage was a crack in the focus distance window. So I took a closeup of the damage for the ad, knocked $100 off the price I had planned to list it at, and it sold quickly.

 

[Del Paso]

I’ve had two drops. The first was my 5DII, which was being carried via a BlackRapid strap connected to the foot of my 70-200/2.8 II with the 2x TC, and the balance was altered to the point that the lens release was pressed by my belt. A meter fall onto pavement, the result was a small scuff on the body and all my lens-specific AFMA values shifted by –10.

The second drop was the aforementioned 70-200/2.8 II. Maybe the lens was bad luck? It was a bit over two years ago, ironically when I was taking pics of the lens to sell on Craigslist, just after getting the RF 70-200/2.8. I failed to carefully clamp the edge of the infinity board, and it rolled up and knocked the lens off the table to the tile floor. The lens functioned fine and IQ was unaffected, the only damage was a crack in the focus distance window. So I took a closeup of the damage for the ad, knocked $100 off the price I had planned to list it at, and it sold quickly.

I wonder what would have happened with a wonderful 3rd party equivalent. Canon lenses withstand lots of abuse.
As to AFMA: Many users forget that no lens (or should I rather speak of camera) is AFMAd forever. There's wear and setting in and of the mirror mechanism, which results in a defocusing. Huge advantage of mirrorless...

 

[SwissFrank]

One cannot generalize here, it all depends on how thick metal is. I've sometimes dropped Leica R lenses, never had more damage than the odd scratch.

I've dropped Leica M lenses and bodies about 6 times and needed to send for service 6 times.

I've dropped Canon EF gear about 200 times and needed to send for service 3 times.

I feel the RF stuff is probably stronger than EF, BUT, is easier to mark. As I sold off my EF gear and replaced with RF, I was constantly surprised by how good condition the gear still looked.

 

[Del Paso]

The RF 85 has added shock protection for "turbulent situations." I bet it's perfectly fine!

Or did you mean for turbulent users?

 

[Del Paso]

I've dropped Leica M lenses and bodies about 6 times and needed to send for service 6 times.

I've dropped Canon EF gear about 200 times and needed to send for service 3 times.

I feel the RF stuff is probably stronger than EF, BUT, is easier to mark. As I sold off my EF gear and replaced with RF, I was constantly surprised by how good condition the gear still looked.

Mechanical gear is far more likely to suffer damage from dropping than electronic gear.
Never had issues with dropped Leica lenses, but the sensitive rangefinder needed readjusting. Easily done if you know how. If you send the body for rangefinder adjusting, chances are high you won't be happy, unless you also send your lens...
But I keep wondering how it can be you so often drop your equipment.

 

[SwissFrank]

But I keep wondering how it can be you so often drop your equipment

OK over 30 years that'd be once every couple months. Maybe I'm just dreaming and it wasn't that often? It's usually when changing lenses. I know I've had to send the M6, the 35/1.4ASPH twice, and the 75/1.4 once. The second time the 35/1.4 was dropped the front ring was bend very notably but it seemed to still work fine, so I only had it fixed while service/inspecting before selling. So 4x for the Leicas, probably not 6. Canon I know my 70-200/2.8 (pre-IS) got a chip in the front element and I still could sell it for like a $60 discount on eBay, sold for like $740 when they were going more like $800.

 

[AlanF]

OK over 30 years that'd be once every couple months. Maybe I'm just dreaming and it wasn't that often? It's usually when changing lenses. I know I've had to send the M6, the 35/1.4ASPH twice, and the 75/1.4 once. The second time the 35/1.4 was dropped the front ring was bend very notably but it seemed to still work fine, so I only had it fixed while service/inspecting before selling. So 4x for the Leicas, probably not 6. Canon I know my 70-200/2.8 (pre-IS) got a chip in the front element and I still could sell it for like a $60 discount on eBay, sold for like $740 when they were going more like $800.

I can only repeat this from earlier today:

I've admired your buying and selling skills over the years. Ok, I can buy used but selling at 80% of cost is way beyond me!

 

[EricN]

I wonder what would have happened with a wonderful 3rd party equivalent. Canon lenses withstand lots of abuse.
As to AFMA: Many users forget that no lens (or should I rather speak of camera) is AFMAd forever. There's wear and setting in and of the mirror mechanism, which results in a defocusing. Huge advantage of mirrorless...

Don't you know? Upsidaisium is used in all lenses EXCEPT Canon.