Leica T performs digital lens correction , a claim by dpreview.com

[Carbon111]

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But I've been told by others (in this thread) that the software corrections are as much a part of the overall Leica lens designs as the physical elements - confused

 

I think the software is a very secondary, but still very necessary thing.

 

I gather people's main complaint is the barrel distortion at the wide end of the new zoom.

 

The new zoom lens requires slightly more correction than M lenses because you need to fix residual geometric distortion and not just chromatic aberration or vignetting. With primes, its easy (relatively) to correct optically for that kind of distortion because the focal length never changes.With a zoom that is 18mm at its wide end and 56mm at the long end, you have a puzzle of sorts - you need to design as much distortion out as you can...zooms will often go from pincushion at one end to barrel at the other. At 18mm there's some barrel so it's taken care of in software. Could they have corrected better? Possibly, but you may need a larger lens or more elements and you start to get to the point of diminishing returns.

 

Look at the Canon 24-105L at its wide end sometime and consider how bad its geometric distortion is relative to its physical lens size. And this is one of their high-end "Luxury" lenses.

Slap it on a 5DmkII and it's terrible at 24, put it on a 5DmkIII and it's very nice due to the software correction in the mkIII.

[mjh]

Jono, I'm only going on what I've read on DPReview

... which doesn’t contradict what Jono said: the corrections are stored as opcodes to be applied (or not) by the raw converter; the image data itself are still as raw as it gets.

[diogenis]

Since so many Leica buyers are fixated on lens quality, maybe each purchase should come with an intro course in lens design.

 

As for the T system in general... Leica finally produced a camera that has all of the design elements that Leica forum members have been clamoring for,

 

They are giving you MTF graphs that are not ashamed of... And in fact they are doing that at various apertures. So they are giving you plenty of MTF graphs that you can use to compare lenses. Not many manufacturers do that and those that do only give them for an aperture setting, which is obviously not wide open ofcourse.

[rosuna]

They are giving you MTF graphs that are not ashamed of... And in fact they are doing that at various apertures. So they are giving you plenty of MTF graphs that you can use to compare lenses. Not many manufacturers do that and those that do only give them for an aperture setting, which is obviously not wide open ofcourse.

 

Where are those MTF graphs?

[hoppyman]

Even the EVF is doubtful. Sure - a huge -and on the face of- it inexplicable price difference for the same thing. Leica and Olympus clearly used the same Chinese manufacturer. But do we know the price they were charged? It is not unthinkable that Olympus was able to negotiate a considerably better price than Leica by ordering a far larger number.

Until we know the cost of procurement we cannot know the markup.

 

For one example (of more rangefinder styled cameras) Fujifilm have stated that by March 2011 they had sold more than 10 million units in the X Series. So yes it seems rather likely that the Japanese manufacturers do benefit from economy of scale in the products that they produce and sell!

 

In my country at least the prices for the new T lenses are about 50% of that for many M lenses.

The CEO himself already stated here last year that at least some of the T lenses would not be manufactured by Leica themselves due to the cost reasons.

 

There really seems to be some misunderstanding on the nature of the corrections performed in any case and the original DPReview claim was not that the corrections are unusual but that Leica Camera told them there were none. A Leica representative has already posted to their forum that there was apparently some misunderstanding on what was said and Sandy McGuffog here has already explained exactly what is happening in the files and why.

[earleygallery]

... which doesn’t contradict what Jono said: the corrections are stored as opcodes to be applied (or not) by the raw converter; the image data itself are still as raw as it gets.

 

And it's possible to see the uncorrected file with the software supplied by Leica? That's not what DPR say.....who is right?

[earleygallery]

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Do you think people buy those brushes as a 'statement' or are they expensive because they're the best brushes for a particular type of work?

[Rick]

And, let's keep this in perspective. DPReview is a couple of guys who live in my city and have a web site and take crappy pictures around my town with the cameras they review. So what? It isn't like they are journalists or famous photographers or something. Why on earth do people listen to this stuff? Go look at the camera yourself and take a memory card and look for yourself. Why do so many people get so worked up over some internet site that so far has made an unsubstantiated claim based on something "they heard." No source reported in their camera blog. In the world of real reporting their editor would have asked for their source and checked before this would have even been printed.

 

Flash: Anyone can have an internet site and run it out of their house.

[earleygallery]

And, let's keep this in perspective. DPReview is a couple of guys who live in my city and have a web site and take crappy pictures around my town with the cameras they review. So what? It isn't like they are journalists or something. Why on earth do people listen to this stuff? Go look at the camera yourself and take a memory card and look for yourself. Why do so many people get so worked up over some internet site that so far has made an unsubstantiated claim. In the world of real reporting their editor would have asked for their source and checked before this would have even been printed.

 

Flash: Anyone can have an internet site and run it out of their house.

 

So you're saying they're wrong on these points? Have you a link to a source showing the correct information?

[wattsy]

And, let's keep this in perspective. DPReview is a couple of guys who live in my city and have a web site and take crappy pictures around my town with the cameras they review.

 

I thought dpreview were London based – somewhere near London Bridge (hence all the photos of Tower Bridge, HMS Belfast, etc.). I think they were bought by Amazon a few years ago (which might explain the Seattle connection?).

[Rick]

I thought dpreview were London based – somewhere near London Bridge (hence all the photos of Tower Bridge, HMS Belfast, etc.). I think they were bought by Amazon a few years ago (which might explain the Seattle connection?).

 

I recognize most of their review shots and they are all Seattle area.

[wattsy]

I recognize most of their review shots and they are all Seattle area.

 

I'm obviously a bit behind the times. It certainly used to be boring shots taken in the London Bridge area (red phone boxes, person looking bored at a pub table, more street furniture, etc.) but I guess Amazon could only stay hands off for only so long.

[jaapv]

Do you think people buy those brushes as a 'statement' or are they expensive because they're the best brushes for a particular type of work?

 

Exactly the right question to ask for the Leica T as well, imo. I'm sure differrent persons will arrive at different answers in both cases.

[earleygallery]

DPReview is a couple of guys who live in my city and have a web site and take crappy pictures around my town with the cameras they review.

 

About this site: Digital Photography Review

 

Not quite what you think Rick!

[Rick]

So you're saying they're wrong on these points? Have you a link to a source showing the correct information?

 

I don't have to link to prove they are wrong. They need to provide a link to support their claim if, they want to have any credibility. I could ask who is their source when they say that, "they heard." Heard from who?

 

I have never seen anything from Leica other than all of their statements about how optically corrected the lenses are. DPReview has said they heard the lenses use optical correction rather than software. DPReview doesn't even state that they heard Leica say this. Just, they heard. And, you are running with that here on the forum?

 

Have you even gone and looked at the camera James?

[Rick]

About this site: Digital Photography Review

 

Not quite what you think Rick!

 

So what, the curriculum vitae states the editor launched the web site from his bedroom. Have you read the other profiles?

[earleygallery]

I don't have to link to prove they are wrong. They need to provide a link to support their claim if, they want to have any credibility. I could ask who is their source when they say that, "they heard." Heard from who?

 

I have never seen anything from Leica other than all of their statements about how optically corrected the lenses are. DPReview has said they heard the lenses use optical correction rather than software. DPReview doesn't even state that they heard Leica say this. Just, they heard. And, you are running with that here on the forum?

 

Have you even gone and looked at the camera James?

 

But you're complaining about DPReview making unsubtantiated claims by making usubtantiated claims yourself!

 

Wasn't there a comment above quoted from a Leica person referring to their statement about optical correction?.....

[jonoslack]

Jono, I'm only going on what I've read on DPReview;

 

Because the profiled corrections are mandatory in ACR, we decided to look at the underlying data using a raw converter which won't apply them by default. For this we chose RawTherapee (4.0.12): a nice GUI around built around the DCRaw converter. The results are pretty interesting: Leica is clearly applying in-camera software corrections to the image projected by the lens onto the sensor.

 

... which doesn’t contradict what Jono said: the corrections are stored as opcodes to be applied (or not) by the raw converter; the image data itself are still as raw as it gets.

 

 

And it's possible to see the uncorrected file with the software supplied by Leica? That's not what DPR say.....who is right?

 

So you're saying they're wrong on these points? Have you a link to a source showing the correct information?

 

Hi There James

No - they aren't wrong, but perhaps you are misunderstanding.

 

The lens corrections are applied to the JPG files automatically and can't be removed.

 

If you shoot RAW, then the lens corrections are not applied to the data from the sensor - they are a list of instructions to the RAW converter - Lightroom will apply them by default (I'm not sure if you can choose not to apply them in LR - I'm sure someone else will know (I use Aperture)).

 

If you use a different converter which either doesn't apply the lens corrections automatically, or doesn't apply them at all, then they are not applied. As Michael said, these are optcodes which are included in the RAW file (which is a package rather than just the data from the sensor - it also holds exif information etc. etc.). There are other optocdes for dealing with Chromatic aberration etc.

 

Almost all modern zoom lenses are designed to use these corrections (why would you not if it improves the image quality). They aren't a lazy short cut, but an extra opportunity.

 

So - with respect to the T - you can choose to apply them - or not. I actually quite agree with AlanG (I think it was Alan) who said he'd rather not apply them to landscape and some other situations where a bit of distortion isn't noticeable but maximum sharpness is important.

 

But of course, if you have the T and you have a shot where you'd rather not apply the opt codes then you can use a different RAW converter to create a TIFF file which you can use in your normal workflow (let's face it, it's not going to be every shot).

 

All the best

[imants]

Most T owners are deemed to be JPG shooters and that is where the camera is pitched ............ stating but you can shoot RAW and process in a raw comverter will just get you a blank response. .......... it is a lens with software correction Sure quibble

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[Steve P]

And, let's keep this in perspective. DPReview is a couple of guys who live in my city and have a web site and take crappy pictures around my town with the cameras they review. So what? It isn't like they are journalists or famous photographers or something. Why on earth do people listen to this stuff? Go look at the camera yourself and take a memory card and look for yourself. Why do so many people get so worked up over some internet site that so far has made an unsubstantiated claim based on something "they heard." No source reported in their camera blog. In the world of real reporting their editor would have asked for their source and checked before this would have even been printed.

 

Flash: Anyone can have an internet site and run it out of their house.

 

Along with the at times somewhat rabid forum content, Dpreview produce plenty of extensive, detailed, interesting content, including thorough reviews which I, and I'm sure many others, find useful. Are they without fault? No, but then who is? I don't expect to find great art or mind blowing images in their test pages, and I don't think their staff make too many claims for themselves in that regard. I use their site primarily for finding information on gear. Anything else of interest, I take as a bonus and then move on.

That's a hell of a lot of content from a couple of guys in Seattle. They must be shagged out!