Still waiting for high MP canon while Nikon is coming out with new 800

[Loswr]

The rub comes with the size of the photosites. As we stand today, the size of the photosites of a "full-frame" sensor are larger than those of a "crop-frame" sensor. This means that one photosite of a "full-frame" sensor collects more light than a photosite of a "crop-frame" sensor simply because it has a larger area that is illuminated. On a "crop-frame" sensor, that same area equal to the size to one photosite of a "full-frame" sensor is shared by several photosite. Thus they also have to share the light falling on said area.

This means that a "full-frame" sensor with the same photosite density as a "crop-frame" sensor will perform equally to the "crop-frame" sensor in terms of image quality ... and, of course, vice versa.

No, it doesn't mean that. Bigger photosites are better, and bigger sensors are better, too. An 18 MP FF sensor will deliver better IQ than an 18 MP APS-C sensor because both pixels and sensor are larger. An 18 MP FF sensor will deliver better IQ than a 7MP APS-C sensor, even though the pixel sizes are identical, becuase the FF sensor is larger.

You're suggesting that if I crop an APS-C FoV from a shot with my 1D X, that the IQ of the resulting 7 MP image will be the same as the IQ an uncropped image (assuming I adjusted the framing with a zoom lens or changing the distance). Sorry, that's simply not true.

For example, see Roger Clark's analysis, the AIQ graph:

http://www.clarkvision.com/articles/does.pixel.size.matter/#sensorconstant

If you compare the dashed lines (theoretical ideal performance for a given sensor size), you'll see that the peak performance for 1.6x crop and FF is at a pixel pitch of ~5 µm - the same photosite density on both formats. But the FF sensor delivers a much higher apparent image quality.

 

[Sella174]

In other words, not usefulness on APS-C formats corner quality color quality. Now we have a reasonable idea of what moving the goalposts is. And congrats on being preposterously arrogant!

Your question was: "What do you expect to get from an EF-S L prime that you can't get from an EF L prime?" Therefore I did not mention the current attributes of L-lenses, because you specifically asked for what it was that I couldn't already get from using EF L-lenses and thus, for instance, good colour rendition and excellent corner quality are implied by default. And, even though I most definitely am "preposterously arrogant", I still won't stoop so low as to slap derogatory labels on you.

 

[3kramd5]

...and only make up 0.00............1% of Canon users?

...calculate what is 1% (the figure you so randomly plucked from others' posts)

Actually, the number he suggests is far less than 1%. He didn't pluck it from anywhere, he wrote it as to mean vanishingly small.

Um, okay, but that's not what I asked. At least, that's not what I intended to ask. Let me add the missing letter to my question:
What do you expect to get from an EF-S L prime that you can't get from an EF L prime?

An EF-S L-prime would take advantage of the shorter "back-focus" distance. This could possibly eliminate the need for a retro-focal design in certain focal lengths, as an example. If you don't know why this is desirable, then you also wouldn't understand it if I explained it to you. And I suspects you don't, which why you also cannot fathom the point of EF-S primes (L or not).

And sure, I'll bite. I may not understand, although I don't know whether that's a reflection on me or on your ability to explain things.

Initially, I do not understand, but I have no qualms about admitting such.

Suggested advantage of EF-S L over EF L: A shorter back focas distance can eliminate retrofocal designs.

Don't retrofocal designs increase the back focus distance? How does reducing the back focus distance eliminate the need to increase the back focus distance? If the goal is a shorter back focus distance, then you are talking telephoto, not retrofocal, right? Maybe not.

 

[Sella174]

You're suggesting that if I crop an APS-C FoV from a shot with my 1D X, that the IQ of the resulting 7 MP image will be the same as the IQ an uncropped image (assuming I adjusted the framing with a zoom lens or changing the distance). Sorry, that's simply not true.

Let's not assume, because by doing that you are changing the parameters of the experiment whilst conducting said experiment by introducing unquantified optical variances.

Redo the experiment. And please leave DoF at home.

 

[3kramd5]

In other words, not usefulness on APS-C formats corner quality color quality. Now we have a reasonable idea of what moving the goalposts is. And congrats on being preposterously arrogant!

Your question was: "What do you expect to get from an EF-S L prime that you can't get from an EF L prime?" Therefore I did not mention the current attributes of L-lenses, because you specifically asked for what it was that I couldn't already get from using EF L-lenses and thus, for instance, good colour rendition and excellent corner quality are implied by default.

Fair enough. I was still in the mindset of the mis-worded question and subsequent answer.

And, even though I most definitely am "preposterously arrogant", I still won't stoop so low as to slap derogatory labels on you.

Instead, you'll suggest (oddly since you have zero information to go on regarding how I choose glass) that I either don't care about color or image quality ("I have found that L-lenses generally have better colour and more pleasing image rendition than non-L-lenses (made by Canon). But I suspect you don't view lenses in this light.") or that I am somehow incapable of learning a concept ("If you don't know why this is desirable, then you also wouldn't understand it if I explained it to you). I prefer to speak plainly.

 

[Loswr]

Let's not assume, because by doing that you are changing the parameters of the experiment whilst conducting said experiment by introducing unquantified optical variances.

Redo the experiment. And please leave DoF at home.

Changing the distance would alter only perspective, an aesthetic change with no relevance to the sensor comparison.

Please leave your futile and meaningless objections at home. No, wait...that would require you to admit your error.

 

[Sella174]

Don't retrofocal designs increase the back focus distance? How does reducing the back focus distance eliminate the need to increase the back focus distance? If the goal is a shorter back focus distance, then you are talking telephoto, not retrofocal, right? Maybe not.

Broadly speaking, that is correct. However, the need for a retro-focal design is linked to the focal length of the lens and the desired image circle it must project.

I'll explain this with an example: a 50mm lens is a 50mm lens because that is the distance from the front element to the focal plane (e.g. the sensor or the film). Now, in the real world this 50mm generally includes a fair bit of the space inside the camera ... where the mirror swings in a Canon DSLR. Not enough space, so we must move the lens forward, i.e. increase the back focus distance. The answer is the retro-focal design.

Now, as the EF-S mount has a shorter back focus distance (smaller mirror), one could design some lenses without resorting to a retro-focal design. (This is also why mirrorless is so appealing in terms of lens designs.) Or use less of a retro-focal design. Less elements within a lens is always better ... up to a point, anyway.

Another factor is the effect that as the image circle becomes smaller, as with an APS-C sensor, the minimum focal length where one must start using a retro-focal design also decreases.

Plus, the EF-S mount allows for a fair amount of cheating in terms of the size of the optics, but that's another story.

 

[Loswr]

I'll explain this with an example: a 50mm lens is a 50mm lens because that is the distance from the front element to the focal plane (e.g. the sensor or the film).

Wrong. Care to try again?

 

[Sella174]

Instead, you'll suggest (oddly since you have zero information to go on regarding how I choose glass) that I either don't care about color or image quality ("I have found that L-lenses generally have better colour and more pleasing image rendition than non-L-lenses (made by Canon). But I suspect you don't view lenses in this light.") or that I am somehow incapable of learning a concept ("If you don't know why this is desirable, then you also wouldn't understand it if I explained it to you). I prefer to speak plainly.

At some point you were unwilling to even consider my opinions, but simply followed that of the crowd. This situation seems to have changed. You still don't have to agree with me on anything, everything and this.

 

[Sella174]

Changing the distance would alter only perspective, an aesthetic change with no relevance to the sensor comparison.

No further comment ... it is futile.

 

[sdsr]

Think about this: if all/most hobbyists, enthusiasts and maybe future pros are only shooting for "full-frame", then why are "crop-frame" systems like micro-4/3 and X even selling? Granted, sales are not anywhere near that of Canon's Rebel jobbies, but that is not their intended target market. Look at how good those systems sell and some of the lenses aren't exactly cheap, e.g. the D.ZUIKO 75mm and the FUJIFILM 56mm? It simply means that "full-frame" is not as important as Canon has led you to believe; but that quality is important, irrespective of the form-factor of the sensor/system.

I'm not really sure what your point here is, but "those systems" *don't* sell well, despite their obvious appeal in terms of size and weight etc., and while "quality is important" the best that can be said for M43 is that it's more-or-less as good as APS-C. Neither is as good as FF, even if it's true that in many contexts the difference doesn't matter or isn't noticeable (I'm reminded of an excellent butter commercial in the UK in the late 1970s: some people claim that margarine tastes like butter - but no-one claims that butter tastes like margarine).

As for "not exactly cheap" - well, indeed not. The best M43 camera for stills is probably the OM-D E-M1, but it costs more than just about any APS-C dslr and almost as much as the FF Sony A7 (which is, what's more, smaller). The same is true of the top-level Fuji-X bodies. And when you throw in lenses, all bets are off - there are some very good m43 primes that are fairly inexpensive, but even then there's no equivalent of such "plastic fantastics" as the Canikon 50 1.8s or the Nikon 35mm 1.8. Canon's impressive new APS-C 10-18mm costs $300 without any sort of discount; the forthcoming Olympus 7-14mm will evidently cost c. $1800. And on and on. So regardless of whether you think the resulting image quality is much the same, given the pricing disparity it's hardly surprising that sales of M43 and Fuji X (which doesn't seem to have any bargains either) aren't impressive. (I say that as someone who currently owns FF & APS-C Canon, FF & APS-C Sony and Olympus OM-D M43).

 

[Sella174]

Wrong. Care to try again?

Who cares? I'll just move the lens forward, as all that does is change the aesthetic perception.

 

[3kramd5]

Instead, you'll suggest (oddly since you have zero information to go on regarding how I choose glass) that I either don't care about color or image quality ("I have found that L-lenses generally have better colour and more pleasing image rendition than non-L-lenses (made by Canon). But I suspect you don't view lenses in this light.") or that I am somehow incapable of learning a concept ("If you don't know why this is desirable, then you also wouldn't understand it if I explained it to you). I prefer to speak plainly.

At some point you were unwilling to even consider my opinions, but simply followed that of the crowd. This situation seems to have changed. You still don't have to agree with me on anything, everything and this.

I think you're confusing my questioning your intent or reasoning with an unwillingness to consider your opinions. Really, if I was so unwilling, I wouldn't bother engaging.

 

[Loswr]

Changing the distance would alter only perspective, an aesthetic change with no relevance to the sensor comparison.

No further comment ... it is futile.

Wrong. Care to try again?

Who cares? I'll just move the lens forward, as all that does is change the aesthetic perception.

So you're wrong even about your own behavior. Interesting.

Well, no...not really.

I suppose if you make incorrect statements about basic concepts like what "focal length" actually means, it's probably too much to expect you to understand more complex concepts.

 

[Sella174]

I'm not really sure what your point here is ...

The point was simply that "full-frame" is not the ultimate objective in camera ownership for everyone who is not a "soccer-mom" and that some enthusiasts are quite happy with "crop-frame" cameras. I guess in the same way some are not content with the current 20MP'ish "full-frame" offerings from Canon, even though most "full-frame" users are quite happy as it stands.

 

[Orangutan]

I'm not really sure what your point here is ...

The point was simply that "full-frame" is not the ultimate objective in camera ownership for everyone who is not a "soccer-mom" and that some enthusiasts are quite happy with "crop-frame" cameras. I guess in the same way some are not content with the current 20MP'ish "full-frame" offerings from Canon, even though most "full-frame" users are quite happy as it stands.

So it boils down to these two points?

1. Some people (such as you) think the crop format is just fine, and don't aspire to FF.

2. You want Canon to provide more high-quality (L-grade) lenses for crop.

That's fine; but unless Canon believes there's enough profit to be made, it's just wishful thinking.

 

[Sella174]

So you're wrong even about your own behavior. Interesting.

OK, since my understanding is apparently wrong ... and I want to learn.

Given a "full-frame" sensor and a "crop-frame" sensor, made of the same "sensor technology", i.e. same size photosites, same A/D converter, same everything except area.

The statement is that a "full-frame" sensor gathers more total light than a "crop-frame" sensor.

Explain to me how and why the "full-frame" sensor collects more light in the centre area of the same equivalent size as the "crop-frame" sensor, than does the "crop-frame" sensor; or, stated differently, how and why does light falling in the area on the "full-frame" sensor outside the "crop-frame" equivalent centre area affect the amount of light gather within the designated centre area of the "full-frame" sensor, thereby causing said designated centre area of the "full-frame" sensor to gather more light than the "crop-frame" sensor.

 

[Sella174]

So it boils down to these two points?

Three points, actually. You forgot the +36MP "full-frame" camera, with lenses to match. (Oops, that's a fourth point.)

 

[ajperk]

I'm not really sure what your point here is ...

The point was simply that "full-frame" is not the ultimate objective in camera ownership for everyone who is not a "soccer-mom" and that some enthusiasts are quite happy with "crop-frame" cameras. I guess in the same way some are not content with the current 20MP'ish "full-frame" offerings from Canon, even though most "full-frame" users are quite happy as it stands.

So it boils down to these two points?

1. Some people (such as you) think the crop format is just fine, and don't aspire to FF.

2. You want Canon to provide more high-quality (L-grade) lenses for crop.

That's fine; but unless Canon believes there's enough profit to be made, it's just wishful thinking.

And I think the most important point is the last line there. It may be a cool idea, and some people might really enjoy APS-C only L-series lenses, but it appears (based on the fact that none have been released) that Canon just doesn't think there's a big enough market for it (and if you disagree with this logic, that's fine, but to a first approximation I think it's fairly sound).

I tend to think that's a correct assessment of the market for many of the reasons that have already been discussed. Maybe this will change one day, though I personally doubt it. I think the only way we may one day see L-series lenses of a mount different than EF is if, one day, mirrorless cameras begin to replace DSLRs for professional use (i.e. Canon comes out with a new mount anyway).

Anyway, I've been lurking and following this thread for a while, so I thought I'd make some kind of contribution.

Take care, everyone!

 

[Orangutan]

So you're wrong even about your own behavior. Interesting.

Explain to me how and why the "full-frame" sensor collects more light in the centre area of the same equivalent size as the "crop-frame" sensor, than does the "crop-frame" sensor;

Um, if you're excluding the light outside the center (crop-equivalent) area, you're not comparing a FF to a crop-frame; you're comparing a crop-frame to a crop-frame. The comparison is absolutely meaningless unless you compare the full area of the FF against the full area of the crop-frame.