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Old Mar 10, 2006, 2:16 PM   #101
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eric s

Thanks for pointing out the obvious about the tone of this thread.

As a moderator, I should have said something earlier.

Guys

Let's not get so passionate in our discussion that we cross the line and let it get personal.

Some friendly "ribbing" is OK from time to time if the other person knows it's being done in jest and doesn't mind, since we're a pretty close net group here.

But, let's not go from ribbing to stabbing.

Keep it Civil and debate the issues.

As we get more higher resolution sensors, you'll see a greater difference between lenses, especially if viewing sizes or resoluton changes.

So, we'll run into limitations.

As for how those limitations will effect quality (which is always subjective and based on user expectations of current technology), I sometimes wonder how high the resolution will be on our Television Screens (or whatever we'll call the most popular device for delivering this type of content) in years to come.

We may see a lot of limitations to current resolution images as viewing and printing technology improves (or entirely new methods of seeing imaging/audio content emerge and become popular).

Next thing you know, you'll have the equivalent of the Holodeck on Star Trek for delivering content. :-)

We're already seeing lots of comments from photographers in forums noting that higher resolution sensors need better quality lenses, since defects and limitations are more apparent.

So, I think it's good that we have these types of discussions, so we'll have a better understanding of technology limitations.

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Old Mar 10, 2006, 3:51 PM   #102
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I've read (but I have no experience to back it up) that the 1Ds MkII is outresolving all but the absolute best Canon lenses. It is an interesting problem.

The solution is one of two things (in my mind):

1) No solution... 'cause it doesn't matter. Everyone but the absolutely most picky are happy with the current lenses and what they can resolve. So there is no need to solve the problem. We've just hit the limit of what the market really cares to resolve. Sorta a market driven "quality" limit on images.

2) Better lenses. These will be even more expensive (until some new disruptive technology gets created) and that will seriously limit their sales potential. To the point that it makes me wonder if they have enough of a market to justify their existence.

JimC
Glad to have said it. People generally get along and while they disagree they are polite about it. I greatly appreciate that. It is one of the big reasons I'm still posting after 4 years.

Eric


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Old Mar 10, 2006, 4:09 PM   #103
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eric s wrote:
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I've read (but I have no experience to back it up) that the 1Ds MkII is outresolving all but the absolute best Canon lenses. It is an interesting problem.

The solution is one of two things (in my mind):

1) No solution... 'cause it doesn't matter. Everyone but the absolutely most picky are happy with the current lenses and what they can resolve. So there is no need to solve the problem. We've just hit the limit of what the market really cares to resolve. Sorta a market driven "quality" limit on images.

2) Better lenses. These will be even more expensive (until some new disruptive technology gets created) and that will seriously limit their sales potential. To the point that it makes me wonder if they have enough of a market to justify their existence.

JimC
Glad to have said it. People generally get along and while they disagree they are polite about it. I greatly appreciate that. It is one of the big reasons I'm still posting after 4 years.

Eric

Hi Eric.

I'm not going to comment anymore on the business of cropping factor - as I've said it's been beaten to death:?:

But I agree with you on our cameras now matching the resolving power of lenses.

I used the cheap Sigma 28-300 lens with my D1x. I liked this lens, even if it didn't have the best quality. It's useless on my D2x. My camera out resolves the lens, which was not the case before.

I believe there's a bit more to go, but basically extra MP's past what the new cameras have is going to be wasted.

Some of my Nikon and Sigma primes are still just fine, and the Tamron 28-105 (a lens with quality control problems - I got a good one) is still fine, but the rest of my lenses are now in the bag with the D1x...:roll:

Dave
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Old Mar 10, 2006, 5:03 PM   #104
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eric s wrote:
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1) No solution... 'cause it doesn't matter. Everyone but the absolutely most picky are happy with the current lenses and what they can resolve. So there is no need to solve the problem. We've just hit the limit of what the market really cares to resolve. Sorta a market driven "quality" limit on images.

2) Better lenses. These will be even more expensive (until some new disruptive technology gets created) and that will seriously limit their sales potential. To the point that it makes me wonder if they have enough of a market to justify their existence.
While the current cameras may be aproaching the resolving power of the 100 million lenses already on the market, we can see from the P&S market that this is more a limitation of the existing lenses than lens design in general.

Nevermind that, there are plenty of other factors limiting sensor resolution. Primarily noise, and neccesity.

Given that 6-16mp cameras can create an output of 8x10 through 16x20 prints which are well matched to the resolving power of the human eye at typical (arms length) distances, why would resolution be increased other than as a marketing gimmick? Well, one. That is to get more reach than a 300mm (35mm equivilent) lens without buying the large and expensive long lenses. This is a very common topic, everybody seems to want more megapixels so that they can crop thier pictures more, at least thats the impression you get when looking around the net.

There are too many theoretical limits for the 35mm platform to be used to replace medium format (which is the direction your second point seems to lead). 12-16mp full frame pro-dslr's and 6-8mp APS-C amature dlsr cameras will likely be with us for many years to come, since they work quite well as a practical replacement to 35mm film in all its capacities. Point and shoot cameras may fade into history as the camera is integrated more effectively with the cell phone, and the cell phone with the PC (both of which already exist in the consumer market, but as highly compromised devices).


An interesting note, canon cameras from the 10d, to 1DsMkII, to the 5d all have similarly sized photosites ranging from 6.4 microns to 8.2 microns in size.

Rebel XT Sensor 22.2x14.8mm, 3456 x 2304, 6.4 micron photosites

EOS-10D Sensor 22.7 x 15.1 mm, 3072 x 2048, 7.4 micron photosites

1DsMkII Sensor 24x36mm, 4992 x 3328, 7.2 micron photosites

EOS-5D Sensor 24x36mm, 4368 x 2912, 8.2 micron photosites

(Data from here, verity if you feel so inclined)

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Old Mar 10, 2006, 5:12 PM   #105
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tmoreau wrote:
[quote]eric s wrote:
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Well, one. That is to get more reach than a 300mm (35mm equivilent) lens without buying the large and expensive long lenses. This is a very common topic, everybody seems to want more megapixels so that they can crop thier pictures more, at least thats the impression you get when looking around the net.


Do you really think that a Medium format 39 Meg camera, with a 300mm lens has more "reach" then a D1 (1.75 MP) with an 1100mm lens?

Just asking

Dave
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Old Mar 10, 2006, 5:27 PM   #106
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All magnification does (listen up, kids) is spreads out light that is too close together for the resolution of your sensor/film/eye. If four leaves on the tree fall into one pixel, you get one "dot" or "blur". Spread the light out a little and each leaf will fall on its own pixel. Spread it out a little more, and you will make out stems, then the shape of the leaf, then veins...

That is not what magnification does. It is partially true that the image is spread out, however if you were to merely spread out the image, it would bemore faint wouldnt it? You take a torchthat you can focus and spread out the light, what happens? The light becomes more faint.Take two magnifying glasses one large, one small and focus them on your hand, which one is going to burn you when the circle they make is the same size? The larger glass brings in MORE light. More light means more detail.
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Old Mar 10, 2006, 6:28 PM   #107
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With these assumptions:
- both the 200mm and 300mm lenses are idential except for the focal length. Down to the screws used to hold them together... I mean IDENTIAL.
- I have one camera with a full frame 8MP sensor (4000x2000 pixels)
- I have one camera with a 1.5x "crop" factor 2MP sensor (2000x1000 pixels)
- We will assume the photosites are of similar size, density and "quality". Truly imaging if you just took a knife and cut 1/4 off each side of the 8MP sesor - you'd be left with the middle 1/2 of the sensor and we put that in the other camera.
- The cameras are idential. Same image processing... everything. Imagine that smaller sensor was swapped into the same camera body (not possible in reality, I know.)

In this situation:
- Lets assume a reasonable target distance of 100 feet away. (Ignore the solar system distances like photographing mars. To many issues creep in which we can safely ignore at more reasonable distances.)
- Assume that the two camera bodies are put one above the other on the same tripod.
- Assume the 8MP camera as a 300mm lens. Assume the 2MP camera has a 200mm lens.
- Both take pictures at the same time.
- I go back to my computer and crop the full frame camera's image to the middle 2000x1000 pixels. (we all know that a 1.5x crop factor camera actually as 1/4 the resolution, right?)

Then I believe it is exactly correct to say this (and my personal experience bares this out, DAMN IT):
the images produced, when examined on the computer, will be almost exactly the same (except a slight difference in depth of field & the slight difference in location because the images were not capture from exactly the same point.) Everything will be the same size in the image and will have the same amount of detail.

If this is not true, I'd like to hear why.

While all the factors are the same, there is one difference between the two set ups. One is using a 300mm lens and the other a 200mm lens. The difference is in the glass. To see this difference it is easiest with my example of two magnifying glasses. The more powerful magnifying glass will bring more light through it, therefore being able to burn you. When something is far away from you, the light is more disperssed, just like the light from a torch therefore you need a more powerful lens to capture more of it.

If you look at a laser beam it seems very parallel, however if you were to shine it at the moon, by the time it gets there, it will be dispersed into a wide area correct? It wont just be the tiny point of light you see right in front of you. So if you were using the light from that laser to expose film, it wouldnt be concentrated enough would it? So you would need a lens to focus the light into the small area of film, just like a magnifying glass will focus light from the sun. So if you took two magnifying glasses one more POWERFUL than the other, it will be like the difference when you focus the light from the sun onto your hand, one will burn you the other wont, so in the case of film, its the same, the more POWERFUL lens will bring in more light so will be able to expose the film better. The more powerful lens will be getting more light from the actual subject and less ambient light, therefore will produce more detail.



A 300mm lens is more POWERFUL than a 200mm lens, so it is able to capture light from farther away from the actual subjectand focus more of it into a smaller area. this is why you need to put the lens further away. You probably wont be able to see any difference with the naked eye.
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Old Mar 11, 2006, 12:51 AM   #108
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The problems with this thread are:

No one is interested in listening to the other's viewpoint even thought what is being said is scientifically factual. That does not help the argument.

There many issues: sensors of all sorts, lenses, focal point, multiplier effect, resolution, optical versus digital maginification just to mention a few. So what is the issue in question? These are huge issues when dealt with indiviudally and much more when dealt with collectively. In any argument, the issues must be isolated and focussed upon. In other words, what is the question that is being answered? As I have seen it, everyone seem to set his or her question and attempt an answer. That has not resolved anything. Even where someone has attempted to refocus the issues, folks have simply ignored it and refused to listen.

To be passionate is a good thing, for it motivates one, but let that be responsible, rational and accept the others viewpoint. This way we resolve disputes quickly. The most intelligent, rational person, etc is not all knowing and that is the problem with this thread. As I see it, each one want to have the final say on the matter in question: that is a dangerous precedence.

Here are hints to help: listen, understand the question and its logic, collects the facts that are presented, attempt to answer with good evidence knocking off weak points of the arguement. If your opponent makes a good point acknowledge it. It is PR and it works. That way you make your opponent see the holes in his or her argument. If you don't understand something, ask for clarifications; don't presume to know. In this manner you reach a point where myths are isolated from facts and the question originally asked is answered.

Clarity of the points of your arguement is important. I have seen folks have good points but they are presented wrongly, confusingly and that does not help the argument.

Also the humility of knowing that you are not all knowing helps. Finally keeping yourself cool in an arguement puts you in control and in charge of the situation because you are thinking as opposed to reacting. This is not to say that you may not get angry, yes anger when the need warrants it. Eh, in other words a good balance between the heart and the head:G. The arguement resolved.

Regards. Jaki.
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Old Mar 11, 2006, 5:53 AM   #109
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Mark47 wrote:
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...The larger glass brings in MORE light. More light means more detail.
More light to the sensor/film means some combination of lower ISO, faster shutter speed, and/or smaller aperature. Those changes will (in general) produce more detail, but that doesn't seem to be what you are talking about.
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Old Mar 11, 2006, 8:51 AM   #110
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Mark47 wrote:
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The larger glass brings in MORE light. More light means more detail.

I wouldn't argue with that. You make the assumpution that a longer focal length means a bigger lens and more light. This is not necessarily the case. It depends on the aperture f8 is still f8 I don't set f8 and then a different shutter speed depending on the focal length. Longer focal length lenses tend to be slower lenses as they collect less light because to keep the same maximum aperture the lens would get progessively bigger and heavier.
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