Joining the full frame club

[blue max]

It's easy to have unrealistic expectations from going full frame. When I moved up from a 30d to a 5d, my wife didn't notice any difference in my shots at all. In fact, she commented that less were in focus!

There is a learning curve before you reap the benefits of full frame (well, there was in my case).

There is certainly potential for better quality images, but it's not a given. And indeed your shots may get worse before they get better.

Like using a very fast lens, you need to learn to see the shot before you press the shutter.

I virtually never print out my shots, but it's nice to know I could if I wanted to. I have documented every family event in the last six years and have shots of my kids growing up. It's a joy to see them in high quality and I wish I could turn the clock back and had my latest kit back then.

But don't forget to backup your images as losing the lot is a very real possibility. It happened to me once and I won't let it happen again.

Graham

 

[arad85]

But don't forget to backup your images as losing the lot is a very real possibility.

Amen to that

 

[existent]

If you put the same lens on a full frame and a crop camera, I think that it will pretty much always look a lot better on full frame. The image is just 2.5x bigger, the magnification is lower, the lens is working 2.5x less hard to deliver the same level of sharpness and it's got 2.5x the area to do it with. So the sensor is working less hard also to gather plenty of photons. There will probably be more pixels too, but that's less important.

That's the advantage of full frame - bigger is better. Simple as. There are a few factors at play apart from the lens, but they all compound one on top of the other to deliver much better image quality.

Just on the lens side, what is certainly true is that the centre will always look a lot better on full frame, if only because it doesn't have to find as much resolution at the lower magnification, so contrast and 'punch/pop' is greater.

The edges are a different question because they have never been seen before on a cropper - that's the bit that's been cropped out. So if it's a rubbish lens with poor edge sharpness that's going to show. But I think that the standard of optics we're probably talking about here will have pretty good performance right across the frame, so the edges too will also look good.

It's a complicated question that invloves a lot of variables, including focal length and f/number and image circle etc etc, but the bottom line is, if you compare like for like as best you can, full frame will win comfortably - often spectacularly so.

That's what happened to me when I went to try a new 7D against my old 40D, and pretty much by accidenct also tried the same lens on a 5D2. I had to look hard to see the improvement on the 7D vs 40D, but the 5D2 (with roughly the same pixel count as a 7D) was just miles better. Effortlessly wonderful quality. It was like comparing 35mm film to medium format, which for those that remember was absolutely no contest at all.

You do need a big print to really see the benefit though, and of course full frame costs more.

Thanks for the detailed explanation...

Everyday I read these forums, and keep changing my mind between 7D and 5D

 

[HoppyUK]

Sorry, but that's completely wrong...

<snip>

I also think magnification is a red herring...

<snip>

Whichever way you look at it, the FF wins - it's just you need to spend more on glass to do it well.

Not wrong at all. And for that matter I'm not sure where you are disagreeing, given your last sentence.

Magnification is not a red herring, and is in fact at the heart of the whole matter. We are attempting to compare different formats of different size, ie magnification. You also have to consider lens MTF at the different resolution levels, again because of the magnification.

It is actually impossible to make an exact comparsion between the two as things have to change, due to the different magnification. You either have to change the framing, or focal length or the shooting distance, and with that perspective changes and depth of field too. So you end up having to make a few assumptions.

It's a complex combination, but when you add up all the science full frame always wins, or at least always has the potential to do so simply because it is much bigger. Haven't you said the same thing?

Sorry, but I'm not sure I agree with you here. What do you mean by the "same spec"? To me, the same spec as a EF-S 17-55 would be an EF 27-88 which Canon (nearly) do in the 24-70 f2.8. The recent significant price drop suggests (as does the canon rumours site) that a reworked lens with IS is on its way. Yes, it may turn out to be more costly than the EF-S 17-55, but then you have more light to gather and spread over the larger image plane at 70 than at 55 for f/2.8.

To me, an equivalent to the 17-40 would be an EF-S 10-25 as then you'd be covering the same field of view with your sensor.

You can make a lot of different comparisons, but none of them will ever be exact (see above) and a lot of them will not even be close.

I like the 17-40L against the EF-S 17-55 2.8 because the focal lenth range at least starts at the same number and the 17-40L is actually quite a popular choice as a walkabout lens on crop format cameras. It makes the point that if you trade the full frame coverage (which you can never use on a cropper) you not only get more focal length range, but a 100% increase in light gathering. That's the difference.

It's easy to have unrealistic expectations from going full frame. When I moved up from a 30d to a 5d, my wife didn't notice any difference in my shots at all. In fact, she commented that less were in focus!

<snip>

Graham

The 'less in focus' bit sounds like the shallower depth of field you get with full frame, which is worth about one and a quarter stops.

At the end of the day full frame is about image quality, and TBH you have to print fairly big to see the benefit of that. You'll probably never notice it on anything smaller than say A4, or if you only view on a regular VDU or TV.

If you turn that around though, it does give you a much greater cropping option - a kind of digital zoom. It's not the best way to go about things, and it's better to just start with a crop format camera in the first place, but the facility is there.

Then there are the downsides, mainly the substantial extra cost of full frame. It adds up to crop format cameras being the better all round option for most folks, even if full frame is ultimately 'best'.

 

[HoppyUK]

Thanks for the detailed explanation...

Everyday I read these forums, and keep changing my mind between 7D and 5D

You're welcome bud

Have you compared a 7D with a 5D2? Go into dealer, take same shot on both, put card in photobooth and make two big prints.

Have your credit card ready

 

[existent]

You're welcome bud

Have you compared a 7D with a 5D2? Go into dealer, take same shot on both, put card in photobooth and make two big prints.

Have your credit card ready

yup... that's what I need to do... and I will definitely try them both before buying one...

When I think about it, 5D makes much more sense for my use (landscape 95%), but 7D sounds more attractive with all the bells and whistles even though I will not use them all probably

 

[HoppyUK]

yup... that's what I need to do... and I will definitely try them both before buying one...

When I think about it, 5D makes much more sense for my use (landscape 95%), but 7D sounds more attractive with all the bells and whistles even though I will not use them all probably

Yeah, that's the dilemma.

7D does everything pretty well, but 5D2 does landscape and portraity stuff better, but is clearly not so good at long lens action/wildlife.

They're as different as the 1D and 1Ds. Of course, you need both. I hope this comment is helpful

 

[existent]

Yeah, that's the dilemma.

7D does everything pretty well, but 5D2 does landscape and portraity stuff better, but is clearly not so good at long lens action/wildlife.

They're as different as the 1D and 1Ds. Of course, you need both. I hope this comment is helpful

haha.. I wish my bank account agreed on that

 

[amtaylor]

haha.. I wish my bank account agreed on that

Don't we all

 

[arad85]

Not wrong at all. And for that matter I'm not sure where you are disagreeing, given your last sentence.

All I'm disagreeing with is your explanation...

Magnification is not a red herring, and is in fact at the heart of the whole matter. We are attempting to compare different formats of different size, ie magnification.

Different formats of different size??? What is the "magnification" factor of a lens?

All the lens is doing is creating an in-focus image at the image plane. The size of this image is dictated by the focal length of the lens. Whatever sensor you have there, be it a small webcam sensor or a large full frame sensor, they will just sample that image. Assuming a perfect lens that can illuminate an infinitely sized image plane, the bigger the sensor, the wider the field of view you see. That's all.

What the 1.6 crop factor does is it tells you that to project the same field of view onto a full frame sensor, you need to have a lens that is 1.6 times the length as the lens on the APS-C sensor to get the same field of view on a full frame. Once you stop thinking about magnification and start thinking in terms of angles and fields of view, it becomes much simpler (been there, done that when trying to understand astrophotography last year...).

You're then into the megapixels game - more on a small sensor means you are sampling the image on the image plane at an angular resolution which decreases as the number of pixels increases. How do you work out the "magnification" then - it's meaningless....

It's a complex combination, but when you add up all the science full frame always wins, or at least always has the potential to do so simply because it is much bigger. Haven't you said the same thing?

It's not that complex - especially if you start looking at it in terms of the angular resolution of each pixel (which changes as focal length changes).

Effectively we agree on the conclusion, I just feel that your explanation is, at best, confusing....

I like the 17-40L against the EF-S 17-55 2.8 because the focal lenth range at least starts at the same number and the 17-40L is actually quite a popular choice as a walkabout lens on crop format cameras. It makes the point that if you trade the full frame coverage (which you can never use on a cropper) you not only get more focal length range, but a 100% increase in light gathering. That's the difference.

Yup, the 17-55 is a better bet on a cropped sensor - but then it's designed to be as it doesn't have to be so good as far from the central axis of the image plane as the 17-40 does. The 17-55 is also a good 25% more expensive...

 

[Anorakus]

Just a word about pixel count..

21mp on the 5D2 is very nice to have and makes it better than the finest-grained Kodachrome emulsion - something digital SLRs have only achieved in the last couple of years.. BUT..

I've recently had some 16x12" prints made up. In order to satisfy the lab's requirement for 300dpi source files, I had to *reduce* the resolution that came out of my 5D2!!

Go figure

A.

 

[HoppyUK]

All I'm disagreeing with is your explanation...

Okay, but I'm not sure why, or what it is you are trying to clarify

It's not that complex - especially if you start looking at it in terms of the angular resolution of each pixel (which changes as focal length changes).

It is very complex, when you look at all aspects of the whole imaging chain. And you cannot pick and choose individual elements to compare, because when you change format, eveything changes. Adding angular resolution into the mix doesn't make things any easier.

Yup, the 17-55 is a better bet on a cropped sensor - but then it's designed to be as it doesn't have to be so good as far from the central axis of the image plane as the 17-40 does. The 17-55 is also a good 25% more expensive...

17-40L vs EF-S 17-55 is a valid comparison if only because some people buy one or the other lens and use it for much the same thing on crop format cameras. In that sense, it makes the point very well.

 

[arad85]

Okay, but I'm not sure why, or what it is you are trying to clarify

Because to use the word magnification in describing any imaging system is nonsense since it depends what the sensor and output device spatial resolutions are.

As soon as you start thinking about it in terms of fields of view, it becomes much easier to both explain and understand.

 

[arad85]

It is very complex, when you look at all aspects of the whole imaging chain. And you cannot pick and choose individual elements to compare, because when you change format, eveything changes. Adding angular resolution into the mix doesn't make things any easier.

Actually, no it doesn't. If you just change the format, but leave the camera where it is, with the lens on it as the APS-C camera, they are directly comparable. If you're saying changing the lens and distance so you get the same field of view across both sensors (see - angles coming into it) then yes, things change, but in an entirely predictable and quantifiable way.

At the end of the day, like for like, I think fundamentally the bigger sensor wins because it has bigger pixels. I think if Canon comes out with a full frame sensor with pixels the same size as the 7D, I think you'll find the picture quality will suffer accordingly....

 

[HoppyUK]

Actually, no it doesn't. If you just change the format, but leave the camera where it is, with the lens on it as the APS-C camera, they are directly comparable. If you're saying changing the lens and distance so you get the same field of view across both sensors (see - angles coming into it) then yes, things change, but in an entirely predictable and quantifiable way.

Yes, things will be directly comparable in that way because you haven't actually changed anything! The reality is that in any meaningful comparison you have to change the field of view (ie magnification) or the whole excerise is pointless.

And then everything changes, and while it is entirely predictable and qualifiable as you say, it is not directly comparable. Ultimately, the only way to make a direct comparison is to shoot pictures on different formats and see which one you like best. There will be subtle differences in all sorts of areas depending on whether you change the framing by focal length or distance, or maybe a bit of both (that's magnification again), but if you just look at image quality - sharpness, noise, dynamic range etc - full frame will always win.

Because it's bigger, and you have to magnify it less to get the same photograph. Size - magnification - is at the heart, because that is what you're changing.

At the end of the day, like for like, I think fundamentally the bigger sensor wins because it has bigger pixels. I think if Canon comes out with a full frame sensor with pixels the same size as the 7D, I think you'll find the picture quality will suffer accordingly....

That's an interesting point, and one which you touched upon earlier I think.

There are two reasons why smaller sensors deliver lower image quality. They are smaller for a start, but then a lot of the light gathering area is taken up by the walls between each pixel. That's why higher pixel density tends to mean more noise, as there are simply more walls throwing away image forming light.

But if you can reduce the thickness of the walls between the photo sites - with so-called 'gap-less microlenses' then there is no reason why more pixels should automatically equal more noise, and you'd get the benefit of greater resolution potential with no performance downside.

I think that at least partly explains why the 7D is better all round than the 40D, depsite having 80% more pixels over the same area. I know there is some debate about how much better it actually is, but the comparisons that I have been able to make (and I think this isn't too contentious) show the 7D to be both sharper, as you'd expect, and with less noise which is a bit of a bonus. Not massively, but certainly discernably if you look close enough. I'd say about a stop on the noise front for example. I think there may be future development potential in that particular aspect.

Sorry this is probably boring everybody now

 

[arad85]

Because it's bigger, and you have to magnify it less to get the same photograph. Size - magnification - is at the heart, because that is what you're changing.

Umm... you sure about that? To get the same field of view (i.e. same picture - forgetting about depth of field issues) on the bigger sensor, the lens has to spread the image over a larger area (or, in your words "magnify it more")....

It's all down to field of view - this is relatively easy to work out without knowing anything about the back end of the system (you only need focal length and sensor size). I'll ask again, tell me what the "magnification factor" is for any lens without factoring in the pixel size and output resolution of the device rendering it.

Anything that alters the distance to subject will only alter the composition of the image and, ultimately, that isn't a directly measurable factor on image quality. It will give you more or less depth of field and change the perspective, but that does nothing to alter the fundamental quality (sharpness, noise, dynamic range as you mention) of the image.

There are two reasons why smaller sensors deliver lower image quality. They are smaller for a start, but then a lot of the light gathering area is taken up by the walls between each pixel. That's why higher pixel density tends to mean more noise, as there are simply more walls throwing away image forming light.

Not quite. You also have more noise as the sensor noise relative to the number of photons it can pick up due to smaller area of the individual sensor will be higher. A bigger sensor with a longer lens but same f number will capture more photons per pixel (the hole the light is coming through is bigger, so you get more of it to the sensor) which will improve signal to noise ratio thus improving perceived quality.

I think that at least partly explains why the 7D is better all round than the 40D, depsite having 80% more pixels over the same area. I know there is some debate about how much better it actually is, but the comparisons that I have been able to make (and I think this isn't too contentious) show the 7D to be both sharper, as you'd expect, and with less noise which is a bit of a bonus. Not massively, but certainly discernably if you look close enough. I'd say about a stop on the noise front for example. I think there may be future development potential in that particular aspect.

Sorry this is probably boring everybody now

You also have the digital processing coming into play - they use different back ends. One of the things that put me off the 7D was the fact that some were complaining of the low ISO performance not being brilliant either, and that certainly showed in some of the shots people had posted...

TBH, the reason I went for full frame was for low light ability. Perhaps I should have gone for Nikon instead

 

[HoppyUK]

Umm... you sure about that?

<snip>

Yes. I am.

And I've now lost track of the point you are trying to make, especially as we appear to come to the same conclusion.

The size of the sensor drives everything. And while this has numerous effects on the final image, the inevitable outome of a bigger sensor, and the reason why we prefer them, is higher image quality.

The primary contributors to that are a) it has to be enlarged less for a given print size (less magnification) so imperfections are reduced, and b) the lens has to deliver a lower standard of resolution, because it has to be enlarged (magnified) less, therefore contrast is increased, which is basic MTF theory.

That is where the extra sharpness comes from, but the other important factor is less noise especially at high ISO, so c) the more photons that are collected, the less the signal has to be amplified (dare I say magnified less) which reduces noise from the processor.

 

[amtaylor]

Get a room you guys
Hahaha
I almost wish I hadn't bought a new camera.........
Not really

 

[arad85]

The size of the sensor drives everything.

No, it's the size of the pixels that drive everything in terms of image quality, not the size of the sensor. A larger sensor allows you to have more larger pixels - that's all. Putting loads of small pixels on a large sensor would mean your noise performance would fall and quality reduce.

Also, a small sensor with more pixels than a ff sensor would have to be "enlarged" less for a large print. The problem is that the image noise (and hence quality) would be lower.

I think you're intermixing things (and calling it magnification - which - as I've said before is meaningless) and getting the right answer, but your logic doesn't flow correctly. It's not the sensor size that matters, nor is it for the reasons you state....

 

[Richard King]

full frame Vs Crop

Sensor size
the full frame and the crop are recording the photograph from the image in the same plane, it is just the full frame is recording more of it

image courtesy of http://go-dslr.com/explained/explained-crop-and-full-frame-demystified-aps-c-vs-full-frame

Hence if you had two cameras (one cropped sensor one full frame) and attached the same lens, mounted the same distance from a crop sensor and a full frame sensor you will find that you will get exactly the same image in the full frame sensor as the cropped sensor, in the area of the full frame sensor that maps in size and shape and position to the cropped sensor

The difference is that on the cropped sensor, the smaller area IS THE WHOLE PHOTOGRAPH, whereas on the full frame sensor, the rest of the sensor (beyond the bit that maps in size and shape and position to the cropped sensor) is also included inthe photograph

The lens is the same, the lens optics are the same, the size of the sensors collecting the image are different

This is why a crop sensor appears to be a "zoomed in" version of the full framed sensor - because just like if you press the zoom button on the back of your camera, you are electively choosing to look at a smaller patch of the same image


Lenses
Because a full framed image is presenting a wider view of the world, over a wider imaging area, the effect of the edges of the lenses optics are more evident. In the example of the vignetting a few posts above, had the lens been used on a cropped sensor, the issue wouldn't be exhibited, because that part of the image would have been cropped off. That's why DX lenses and the Canon equivalents showed such an apparent improvement in Image quality - essentially because they could now ignore the hardest bit of the lens optics to sort out - off axis performance. These performance issues includes chromatic aberrations, vignetting and resoloution issues

With the advent of full frame sensors, most DX format lenses has such poor performance over the extra area a full frame sensor requires, that they are not use-able. this brought people back to: the old pile of lenses they used to use for film or the new lenses developed for full framed sensors. Even so, some of these lenses still struggle out at the edges, however the performance in the centre of the frame is in the same ball park as DX lenses, and if you put a FX lens on a DX camera, the optical performance is identical, if you consider the size and position of the sensor

Pixel counts
If you have the same pixel count on a full frame sensor, as a crop sensor, and the photosites are correspondingly bigger, more photons will be collected per mm2 meaning less amplification is needed. Theoretically this reduces noise, and ensures cleaner images.

 

[joescrivens]

One of the things I noticed when I moved to full frame is how much harder it was to fill the entire frame with the lens, particularly a fast prime. Taking what appeared to be a "close in" shot of a small cat with a 50mm prime was no problem on the 450D I had, but on the 1Ds I'd hit minimum focus distance long before I had filled the frame. The MFD for the next prime I am going to get (either 100/2 or 85/1.8 - I haven't yet decided) is much the same (in terms of magnification) as the fifty so I have actually factored a 12mm extension tube in so I can once again frame these closer shots. If you do a lot of "close up filling the frame" shots with your 40D, this is something you'll want to consider - it's hard to appreciate just how much more you "see" on an FF camera. In the first place, your 24-105 will appear really wide at 24, and probably lacking at the 105 end. Secondly, you'll see right to the corners so vignetting and other complications will be a LOT more apparent. You may well end up selling it and going for other focal lengths

I paid £560 for my 1Ds; the batteries were as flat as a fluke and it didn't come with a PC interface cable, but as far as I am concerned that's a fantastic deal. It's old, slow and heavy, but very well built, has amazing AF and EF lenses perform as they were originally intended to. On top of that I sold my previous camera (450D) to cover around half the costs. FF doesn't have to be an expensive game.

I found the opposite to this. I found with my crop I never had enough room, my lenses always felt longer than I wanted. I would use my 30mm for the head and shoulders portrait and I could never use my 85, my 100mm or my 70-200 indoors - when I started putting lenses on my full frame it was like my eyes opened. Everything fit so much better!

also I don't know how you can use that 1ds mark 1, I tried a friends and the menu system just seemed so complicated!

 

[joescrivens]

I have to say some of the posts in this thread about magnification and field of view and angles made me want to throw my camera in the bin, talk about taking the fun out of photography!!!!!

lol

 

[amtaylor]

I have to say some of the posts in this thread about magnification and field of view and angles made me want to throw my camera in the bin, talk about taking the fun out of photography!!!!!

lol

+1 I feel my thread has been hijacked rather. It was about me feeling happy about a new camera not the minutia of differences of sensor sizes which come to same conclusion but reach it in a different way and whilst the first couple of posts were interesting the next gazillion.... Or is it billion.... Or have I magnified the number wrong.... Or have the photons got in my eyes.... Needless to say......WE NO LONGER CARE!

 

[arad85]

+1 I feel my thread has been hijacked rather.

Apologies, but that's what happens occasionally

It was about me feeling happy about a new camera

Yup. I'm happy with mine too (or I would be had I not broken it within a few hours).

not the minutia of differences of sensor sizes which come to same conclusion but reach it in a different way and whilst the first couple of posts were interesting the next gazillion.... Or is it billion.... Or have I magnified the number wrong.... Or have the photons got in my eyes.... Needless to say......WE NO LONGER CARE!

Some people do care though and have every right to discuss it.

 

[amtaylor]

May I suggest you start your own post to specifically discuss it then - as you have stopped pretty much every one else from commenting - or as your both repeating the same thing in every post just be happy with your own take on it because your never going to convince each other.

 

[joescrivens]

Some people do care though and have every right to discuss it.

no, seems more like just you and hoppy care while the rest of us want to slit our throats! ha ha

just kidding!

 

[amtaylor]

Why did stars appear in my post?

 

[arad85]

Why did stars appear in my post?

Normally a censored word.... did you misspell as with an extra s?

 

[amtaylor]

Normally a censored word.... did you misspell as with an extra s?

I put the slang shortened form of because. Didn't realise it would censor me. Must remember to use the Queen's English lol. Funny how lol works though. Lol

 

[amtaylor]

http://www.talkphotography.co.uk/forums/showthread.php?t=257756

Here is another topic for discussing the comparison
Ha ha
Lol

 

[joescrivens]

http://www.talkphotography.co.uk/forums/showthread.php?t=257756

Here is another topic for discussing the comparison
Ha ha
Lol

dont you send them over to my thread ruining the magic with their scientific explanations!!!!

 

[amtaylor]

But what about the (2) people that care?

 

[arad85]

dont you send them over to my thread ruining the magic with their scientific explanations!!!!

What... you can take pictures with all this expensive equipment. Now you're taking all the fun out of the technology

 

[arad85]

But what about the (2) people that care?

Or the (2) people that don't

 

[amtaylor]

Or the (2) people that don't

Haha, good one. I reckon we should have a poll

 

[cmjt_uk]

Well i'm 3 weeks in to the world of full frame (5D) and loving it.. Plus the addition of L glass (24-1-5) makes it even better.

One thing though, I have a 5D with a serial number begining with 1 and the screen is dreadfull!! Only reason i went for it, new about the problem beforehand, is that I got it uber cheap and it's in minto condition.

 

[Richard King]

I dont get it - photography is a technical art. Dippy stuff like sensor size is pretty fundamental to the quality and qualities of your photographs

Understanding the very basics, lets you achieve so much more. Understanding just a little bit more, lets you know how and why to shoot all sorts of things that otherwise seem impossible

I did a degree in Optics, and when things get complex, they really do get complex... however I can hand on heart say most of the stuff we are discussing is so basic, I would hope most schoolkids doing science and maths to o'level standard could grasp it

If you dont get it, draw a line diagram of it - it will all start to make sense. Think about the things in your diagram that do change, and that dont change. Hint: the subject doenst change, the subject to camera distance doenst change, the lens - sensor distance doenst change, the only thing that changes is the sensor size... What does change is the size of the sensor, and thats it. All you need to do then is consider the implications of that change - draw it on the diagram the implications are:

The lens needs to produce a image thats acceptable over a larger area

The next thing to consider is what els did or didnt change
i.e. we all know that pixel densities seem to rise with each new camera, so what's really important is figuring out are we cramming more or less pixels into the same space on the sensor

if it is more:
1. does the lens have the resolving power to exploit this
2. what difference does this make to the noisiness of the final image

If it is less:
1. do we actually need a higher resoloution?
2. does the camera exploit the lower pixel count with increased noisless sensitivity

Ideally
A new sensor will have a greater pixel count, have better noisless sensitivity, and be coupled with alens that is capable of exploiting it

Reality
larger sensors coupoled with lenses not designed to perform well on a large sensor = crap image, if you dont have the lenses, stick with a smaller sensor

larger sensor, same pixel count, coupled with lenses that are designed for larger sensors = higher quality images, and generally lower noise

larger sensor, higher pixel count, same pixel density coupled with a lens that can work with the sensor = larger file = more information = generally better quality image when printed at same size (or more flexibility to crop)

Conclusion
Generally larger sensors are better if you have the lenses to go with them, but the confusion arises, because at the same time as increasing the sensor size, the pixel density usually changes, and technology in amplifing the sensors output generally improves. There is no point in buying a camera with a sensor with increased pixel density, if your lens isnt capable of resolving an image distincly enought to exploit the extra refinement the sensor is offering

 

[joescrivens]

I dont get it - photography is a technical art. Dippy stuff like sensor size is pretty fundamental to the quality and qualities of your photographs

Understanding the very basics, lets you achieve so much more. Understanding just a little bit more, lets you know how and why to shoot all sorts of things that otherwise seem impossible

I did a degree in Optics, and when things get complex, they really do get complex... however I can hand on heart say most of the stuff we are discussing is so basic, I would hope most schoolkids doing science and maths to o'level standard could grasp it

If you dont get it, draw a line diagram of it - it will all start to make sense. Think about the things in your diagram that do change, and that dont change. Hint: the subject doenst change, the subject to camera distance doenst change, the lens - sensor distance doenst change, the only thing that changes is the sensor size... What does change is the size of the sensor, and thats it. All you need to do then is consider the implications of that change - draw it on the diagram the implications are:

The lens needs to produce a image thats acceptable over a larger area

The next thing to consider is what els did or didnt change
i.e. we all know that pixel densities seem to rise with each new camera, so what's really important is figuring out are we cramming more or less pixels into the same space on the sensor

if it is more:
1. does the lens have the resolving power to exploit this
2. what difference does this make to the noisiness of the final image

If it is less:
1. do we actually need a higher resoloution?
2. does the camera exploit the lower pixel count with increased noisless sensitivity

Ideally
A new sensor will have a greater pixel count, have better noisless sensitivity, and be coupled with alens that is capable of exploiting it

Reality
larger sensors coupoled with lenses not designed to perform well on a large sensor = crap image, if you dont have the lenses, stick with a smaller sensor

larger sensor, same pixel count, coupled with lenses that are designed for larger sensors = higher quality images, and generally lower noise

larger sensor, higher pixel count, same pixel density coupled with a lens that can work with the sensor = larger file = more information = generally better quality image when printed at same size (or more flexibility to crop)

Conclusion
Generally larger sensors are better if you have the lenses to go with them, but the confusion arises, because at the same time as increasing the sensor size, the pixel density usually changes, and technology in amplifing the sensors output generally improves. There is no point in buying a camera with a sensor with increased pixel density, if your lens isnt capable of resolving an image distincly enought to exploit the extra refinement the sensor is offering

I can honestly say I couldn't agree with you less.

The day I draw a line diagram instead of looking at a photo to decide which is better is the day I'll sell my camera!!

 

[arad85]

What Richard said (and put far more eloquently than I did )

 

[boyfalldown]

+1 I feel my thread has been hijacked rather.

I never understand why people say this - you may of started the thread, but its not yours. Its a discussion forum, thats what happens, things get discussed and the conversation moves along.

It was about me feeling happy about a new camera not the minutia of differences of sensor sizes which come to same conclusion but reach it in a different way and whilst the first couple of posts were interesting the next gazillion.... Or is it billion.... Or have I magnified the number wrong.... Or have the photons got in my eyes.... Needless to say......WE NO LONGER CARE!

you no longer care you mean ;-)