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An appeal to Panasonic regarding MTF data

robin0112358

Active Member
Though I am not an optics expert, I am able to read MTF charts to a reasonable degree, having been trained on the material Zeiss has published on this subject. Complete and accurate MTF charts can tell us a lot about a lens. Not everything, obviously, but nonetheless a good deal about macro contrast, micro contrast, acutance, and even field curvature.

This is an appeal to Panasonic to improve their reporting in this area.

Currently your lens specifications include a single MTF chart with spatial frequency curves at 10 and 30 lp/mm for both sagittal and meridional directions. From the first curve we can get an idea of (macro) contrast and from the second something like sharpness. But I would prefer a 40 lp/mm curve. Because the 30 curve will look "too good" by comparison to a measure at 40 (which corresponds to finer detail).

Please follow Zeiss by providing graphs at 10, 20, and 40 lp/mm. Then all obscurity of language can be put aside and we can make a proper evaluation of objective data.

The other problem is that you publish only a single chart for each prime, measured wide open. This is actually counter-productive for marketing, since most lenses will improve dramatically when stopped down. Please add a chart for the lens at an optimal aperture. Or perhaps several charts... your engineers already have this data.

Finally, I would like an assurance that the data is derived from measured samples of the actual lenses. And not from some idealised optical software accessed during the design process.

I expect accurate technical measurements and transparency of disclosure from a professional company. True, there are few enough who operate in this manner. Panasonic would distinguish themselves by going this route.

I am a happy customer but such data might encourage me to buy more lenses! Thanks for your consideration.
 
I suspect they think (probably rightly) that 99% of their customers wouldn’t know what to do with an MTF chart so I’m fairly sure your appeal will fall on deaf ears. In any case, most people will want to see images rather than look at charts to determine whether a lens matches their needs.
 
In any case, most people will want to see images rather than look at charts to determine whether a lens matches their needs.

The two are not mutually exclusive.

Unless someone else has taken exactly the image I want to take, with exactly the same settings, in the same environment, with the same subject, enveloped in the same mood, the same relationship to subject.... then their image says very little that might inform my photography.

All lenses can take a good photograph and all lenses can take a bad photograph. A few random samples help me much less than an MTF chart and related data (light falloff and distortion curves).

I suspect they think (probably rightly) that 99% of their customers wouldn’t know what to do with an MTF chart so I’m fairly sure your appeal will fall on deaf ears.

Panasonic already provides one MTF chart for each lens, evidence that they at least understand such measurements are useful.
 
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