Filters on tele-zooms

[Del Paso]

When I checked my EF 100-400L II pictures shot yesterday, I had the ugly surprise that they were not as sharp as usual.
I first didn't understand why.
So, I re-calibrated the AFMA, but there was no change, T & W remained unchanged. Since most pictures were shot stabilized, also at short shutter times, I kept wondering.
Until I remembered that the only real change was having added a filter to the lens (B+W Clear filter MRC nano T-Pro).
After removal, sharpness was restored!
Has somebody else experienced the same with a similar highest quality filter?

 

[Old Sarge]

This is, as I'm sure you know, one of the most divisive issues in photography. Or at least the use of "protective" filters on lenses. I used to be on the "keep a filter on all lenses" group, and even have an example of where it probably saved one of my lenses. But I have gone to the other side of the question. There are too many people, many of whose opinions I really respect (like yourself), who have had issues. I the filter you were using is certainly one of high quality. So I am now part of the "trust the lens hood to protect your lens" group.

 

[koenkooi]

I’ve mostly stopped using ‘protective’ filters, unless I know there is going dirt or water flung toward the lens.
And I have had issues with CPL filters that had an even layer of stuff coating it, I now check and clean every filter before heading out.

As for the sharpness issue, you observed it yourself, that is hard to argue against

 

[danfaz]

So I am now part of the "trust the lens hood to protect your lens" group.

I’ve mostly stopped using ‘protective’ filters, unless I know there is going dirt or water flung toward the lens.

I'm in the lens hood camp for protection, as well, except for extreme conditons.

 

[Quack]

Not saying this is the case, but it's possible you had a fake B+W filter. It's been a big problem for B+W and possibly other top brands. I have used the B+W clear filters on numerous lenses and have never noticed a difference with or without. Also using a top level Hoya on my Olympus Telephoto with no noticeable difference in sharpness. I assume you took your shots at the same time under the same atmospheric condition. Maybe the lens makes a difference. Here are shots using an 100-500 zoomed to 500 on my R7 without and with B+W filter. Cell tower about 1/4 mile away. My eye sees no difference. With absolutely no disrespect intended to the poster, my advice to those who read things on the internet and make a decision, it's easy enough to test this yourself. Just make sure you buy your filter from Adorama or B&H, so you get a genuine filter and can return it if it does not work out for you.

 

[Del Paso]

This is, as I'm sure you know, one of the most divisive issues in photography. Or at least the use of "protective" filters on lenses. I used to be on the "keep a filter on all lenses" group, and even have an example of where it probably saved one of my lenses. But I have gone to the other side of the question. There are too many people, many of whose opinions I really respect (like yourself), who have had issues. I the filter you were using is certainly one of high quality. So I am now part of the "trust the lens hood to protect your lens" group.

That's what I've always been doing. Never fond of supplemental glas, I used filters only for specific tasks (CPL, ND).
But because I nearly scratched the front lens of the 100-400, while putting it back into the backpack, with the exceptionally reversed hood, I imagined it safer to use a filter. Normally, I always have the hood on.

 

[Del Paso]

Not saying this is the case, but it's possible you had a fake B+W filter. It's been a big problem for B+W and possibly other top brands. I have used the B+W clear filters on numerous lenses and have never noticed a difference with or without. Also using a top level Hoya on my Olympus Telephoto with no noticeable difference in sharpness. I assume you took your shots at the same time under the same atmospheric condition. Maybe the lens makes a difference. Here are shots using an 100-500 zoomed to 500 on my R7 without and with B+W filter. Cell tower about 1/4 mile away. My eye sees no difference. With absolutely no disrespect intended to the poster, my advice to those who read things on the internet and make a decision, it's easy enough to test this yourself. Just make sure you buy your filter from Adorama or B&H, so you get a genuine filter and can return it if it does not work out for you.

View attachment 215331

Nope, I'm quite convinced it was a genuine top B+W filter, bought from a reputed store, not via internet...I do not have the slightest doubts about B+W's filter quality!
I too wonder what happened. But pictures taken a minute apart, on a heavy Gitzo tripod, spot AF, showed a visible difference between filtered and non-filtered images. Strange, is't it?
I wouldn't have been surprised if I had used a cheaper filter...but maybe my highly reputed store got the filter from a less reputed wholesaler?
Anyway, good to know that high quality filters should not affect images taken with such zooms!

 

[EricN]

Not saying this is the case, but it's possible you had a fake B+W filter. It's been a big problem for B+W and possibly other top brands. I have used the B+W clear filters on numerous lenses and have never noticed a difference with or without. Also using a top level Hoya on my Olympus Telephoto with no noticeable difference in sharpness. I assume you took your shots at the same time under the same atmospheric condition. Maybe the lens makes a difference. Here are shots using an 100-500 zoomed to 500 on my R7 without and with B+W filter. Cell tower about 1/4 mile away. My eye sees no difference. With absolutely no disrespect intended to the poster, my advice to those who read things on the internet and make a decision, it's easy enough to test this yourself. Just make sure you buy your filter from Adorama or B&H, so you get a genuine filter and can return it if it does not work out for you.

View attachment 215331

I was wondering about this possibility, too.
I buy a clear filter when I buy every lens don't notice any change.
Occasionally I use an ND and only notice a small change.
Using contrast filters and diopters I notice a bigger change, but if the use of these filters is more important to me than sharpness, I will accept it.

Unfortunately, for Europeans, it's inconvenient at minimum to buy from US companies. How about buying directly from B+W?

 

[AlanF]

Not saying this is the case, but it's possible you had a fake B+W filter. It's been a big problem for B+W and possibly other top brands. I have used the B+W clear filters on numerous lenses and have never noticed a difference with or without. Also using a top level Hoya on my Olympus Telephoto with no noticeable difference in sharpness. I assume you took your shots at the same time under the same atmospheric condition. Maybe the lens makes a difference. Here are shots using an 100-500 zoomed to 500 on my R7 without and with B+W filter. Cell tower about 1/4 mile away. My eye sees no difference. With absolutely no disrespect intended to the poster, my advice to those who read things on the internet and make a decision, it's easy enough to test this yourself. Just make sure you buy your filter from Adorama or B&H, so you get a genuine filter and can return it if it does not work out for you.

View attachment 215331

I don't whether the right or left has the filter on it. Whatever, the one on the right is very slightly sharper with very slightly better contrast in areas where detail and contrast are more likely to be noticed. I've cut and pasted those here.

 

[Del Paso]

I don't whether the right or left has the filter on it. Whatever, the one on the right is very slightly sharper with very slightly better contrast in areas where detail and contrast are more likely to be noticed. I've cut and pasted those here.

View attachment 215333

This was my first thought as well, almost identical sharpness, but higher contrast for the second picture.

 

[Del Paso]

I was wondering about this possibility, too.
I buy a clear filter when I buy every lens don't notice any change.
Occasionally I use an ND and only notice a small change.
Using contrast filters and diopters I notice a bigger change, but if the use of these filters is more important to me than sharpness, I will accept it.

Unfortunately, for Europeans, it's inconvenient at minimum to buy from US companies. How about buying directly from B+W?

Hm...
I'd say we have a few suppliers who are certainly as reliable as the best you find in the USA. As far as I know, buying from B+W isn't possible.
And it wouldn't make sense for me. I have never scratched one single lens, so, I see no reason for buying more filters. But dropped a few.
The lensshades are always mounted, apart from this one awkward exception (backpack too small to accomodate the 100-400 with shade). But I have a wide choice of backpacks...

 

[EricN]

Hm...
I'd say we have a few suppliers who are certainly as reliable as the best you find in the USA. As far as I know, buying from B+W isn't possible.
And it wouldn't make sense for me. I have never scratched one single lens, so, I see no reason for buying more filters. But dropped a few.
The lensshades are always mounted, apart from this one awkward exception (backpack too small to accomodate the 100-400 with shade). But I have a wide choice of backpacks...

I'm the opposite, I almost never use the lenshood.

 

[neuroanatomist]

I am a filter user, have been all along. I occasionally test new filters when I receive them, and have not noticed any detrimental effects on IQ in most situations. The exception is with a bright light source in or just outside the frame, and in that case a filter (even a high quality one like a B+W) will lead to increased flare and veiling glare, and those manifest as a loss of contrast.

Here are 100% crops from my most recent test, of the B+W Master Clear filter in the 112mm size, on my RF 100-300/2.8L, with images of my ISO 12233-type chart (the same 'enhanced' versions that Bryan/TDP uses for the sharpness comparisons). Top panel is without the filter.

 

[Del Paso]

Today I will buy the same B+W filter from a different dealer. I'll inform you about the results as soon as possible.
Im still believe there was something wrong with the first one.
We'll see...

 

[AlanF]

Today I will buy the same B+W filter from a different dealer. I'll inform you about the results as soon as possible.
Im still believe there was something wrong with the first one.
We'll see...

For some reason, the EF 100-400mm II has been reported for having issues with filters. I never had any, using Marumi or B+W.

 

[Del Paso]

For some reason, the EF 100-400mm II has been reported for having issues with filters. I never had any, using Marumi or B+W.

This is reassuring! I hadn't read or heard about such issues.
Thanks to your answer, I've decided against buying another filter. After all, I haven't scratched its front lens in 7-8 years.
I'll simply use my larger backpacks, so I can keep the hood on.

 

[Walrus]

I'm in the lens hood camp for protection, as well, except for extreme conditons.

Agreed; always lens hood. I use filters (99% ND's for shooting strobes wide open in the sun without going HSS) when needed, otherwise there's no reason in putting anything in front of my lenses, adding another glass/air surface in front of them.
If those "protective" filters wouldn't kill quality (even expensive stuff in 100$'s; of course not talking about 2$ aliexpress sh*t), lens manufactures would integrate themselves in front of the lenses (something more permanent, not just a screw-on), so they could sell you spares when/if you break one; if they don't do it, renouncing to a possible business, it's because they know they weaken the optic scheme.

Protective filters it's just a thing that someone was paid to sponsor, and internet people followed; power of the influencers.

 

[Del Paso]

Agreed; always lens hood. I use filters (99% ND's for shooting strobes wide open in the sun without going HSS) when needed, otherwise there's no reason in putting anything in front of my lenses, adding another glass/air surface in front of them.
If those "protective" filters wouldn't kill quality (even expensive stuff in 100$'s; of course not talking about 2$ aliexpress sh*t), lens manufactures would integrate themselves in front of the lenses (something more permanent, not just a screw-on), so they could sell you spares when/if you break one; if they don't do it, renouncing to a possible business, it's because they know they weaken the optic scheme.

Protective filters it's just a thing that someone was paid to sponsor, and internet people followed; power of the influencers.

Have you ever tried to take pictures of motocross without using protective filters? Wish you good luck removing the mud from the front lens, a filter can simply be washed in the kitchen.
As to OEMs adding systematically filters, why should they? Adding costs (and flare) without benefits ? In exceptional cases, when more protection was required, some big whites got a clear filter from Canon, which was part of the optical calculation. And the R-EF filter adapter also NEEDS a filter.
Nothing to do with a sponsorised influencer's conspiracy.

 

[neuroanatomist]

…lens manufactures would integrate themselves in front of the lenses (something more permanent, not just a screw-on), so they could sell you spares when/if you break one; if they don't do it, renouncing to a possible business, it's because they know they weaken the optic scheme.

Canon used to do exactly that with their most expensive lenses. Supertele lenses prior to the MkII IS versions had a built-in protective front element, a flat piece of glass for just that purpose – easy and relatively inexpensive to replace, unlike the large refractive elements at the front. Canon stated that they stopped using them to save weight, judging the trade off worth the greater risk of an expensive repair.

Nikon has used them in more recent lenses, you can see it here in the 400/2.8 from 2019:



So is Nikon choosing to ‘weaken the optic scheme’ (as you put it) of a lens costing >$11K? I wonder who knows more about optics, you or Nikon’s lens designers? No, I don’t wonder about that, at all.

Also worth noting that several Canon L-series weather sealed lenses require a screw-on front filter to complete the sealing. So I guess you don’t know more than Canon’s lens designers, either.

 

[neuroanatomist]

And the R-EF filter adapter also NEEDS a filter.
Nothing to do with a sponsorised influencer's conspiracy.

Wrong. It only NEEDS a filter if you NEED to focus the attached lens on distant subjects.