Canon glass vs ______ glass

[Mitch.Conner]

I found the article from Lens Rentals comparing Canon's 24-70 and 70-200 zooms to Nikon's. I thought it was interesting that the comparisons were done in such a way that different camera bodies didn't taint the results.

Out of curiosity - are there other similar comparisons out there? I can't find any that isolate the lenses.

 

[9VIII]

I wouldn't be surprised if Roger is the only person using an optical bench who has the legal authority to post results openly.

 

[AcutancePhotography]

But since a photographer uses a lens with a camera, what is the real value of a lens only test?

To me a more useful test is an evaluation of the entire camera and lens system as that is what the customer will be using.

I would think a better use of time would be to conduct a standardized set of tests with a lens on all the bodies.

 

[rs]

But since a photographer uses a lens with a camera, what is the real value of a lens only test?

To me a more useful test is an evaluation of the entire camera and lens system as that is what the customer will be using.

I would think a better use of time would be to conduct a standardized set of tests with a lens on all the bodies.

There is more value in measuring the system as a whole, but sometimes comparisons of one component can be useful. For instance, a lens can be a long term investment while the body is just a passing phase. In which case, some potential customers see lens only comparisons from different vendors as a useful test. Eg 5D mk III vs D810 will give an advantage to the lens mounted on the D810. Now Canon have the 5Ds, the tables are turned.

 

[Ozarker]

I wouldn't be surprised if Roger is the only person using an optical bench who has the legal authority to post results openly.

Legal authority to post results? Why would one need any legal authority? Just wondering.

 

[Mt Spokane Photography]

I find more value in measuring a lens as a standalone. This tells you the capability of the lens as well as any internal issues such as decentering, astigmatism, etc. A lens will act differently on different camera bodies, so its best to test it standalone.


I think Lens Rentals bought it to check returned lenses for aberrations and internal damage. Doing that when mounted to as camera affects the results, its better to check the lens alone. If the lens shows need of adjustment, they can better tell which adjustment is needed to fix it.

They did not purchase the expensive equipment in order to compare results across manufacturers, that's just something they did out of curiosity while learning to use the equipment. Its possible that we will see some more comparisons.

 

[3kramd5]

I wouldn't be surprised if Roger is the only person using an optical bench who has the legal authority to post results openly.

Legal authority to post results? Why would one need any legal authority? Just wondering.

The only other parties likely using optical benches are the lens makers, and any data would be IP and require company authorization to publish. Maybe that's what was meant.

 

[AlanF]

I wouldn't be surprised if Roger is the only person using an optical bench who has the legal authority to post results openly.

Legal authority to post results? Why would one need any legal authority? Just wondering.

The only other parties likely using optical benches are the lens makers, and any data would be IP and require company authorization to publish. Maybe that's what was meant.

If it was, then it is still wrong. lensfreaks.com and objektiv.se publish MTFs of Canon, Sigma, Nikon, Tamron etc measured on optical benches, for a start.

 

[3kramd5]

I wouldn't be surprised if Roger is the only person using an optical bench who has the legal authority to post results openly.

Legal authority to post results? Why would one need any legal authority? Just wondering.

The only other parties likely using optical benches are the lens makers, and any data would be IP and require company authorization to publish. Maybe that's what was meant.

If it was, then it is still wrong. lensfreaks.com and objektiv.se publish MTFs of Canon, Sigma, Nikon, Tamron etc measured on optical benches, for a start.

You learn something every day.

 

[jthomson]

I find more value in measuring a lens as a standalone. This tells you the capability of the lens as well as any internal issues such as decentering, astigmatism, etc. A lens will act differently on different camera bodies, so its best to test it standalone.

I think Lens Rentals bought it to check returned lenses for aberrations and internal damage. Doing that when mounted to as camera affects the results, its better to check the lens alone. If the lens shows need of adjustment, they can better tell which adjustment is needed to fix it.

They did not purchase the expensive equipment in order to compare results across manufacturers, that's just something they did out of curiosity while learning to use the equipment. Its possible that we will see some more comparisons.

I know they got Olaf to help them check and repair lenses, but I think the optical bench was just another new toy for Roger. ;D

Very definitely agree about testing independent of camera bodies. Look at the DxO mark scores for the Nikon and Canon 500mm f4 lenses. Which lens would you rather have, knowing that sensors keep improving?

 

[Mt Spokane Photography]

Very definitely agree about testing independent of camera bodies. Look at the DxO mark scores for the Nikon and Canon 500mm f4 lenses. Which lens would you rather have, knowing that sensors keep improving?

Test values can only be compared against the same body. Unless you use a optical bench. This is the second optical bench for lens rentals, their earlier one may still be in use.

I had a optical bench in my lab where I worked. We used it to test fiber optic components from various sources and worked with them to improve the connection methods. The telecom industries used single mode fiber and fused the joints, but for our industry, we were using short runs of multimode and used various types of connectors. Those connectors sometimes had lenses in them.

At the time, use of fiberoptics in our industry was in a development phase, data speeds have leapfrogged since then. We were the first to use a production fiberoptic lan in our product back in the mid 1990's.