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02-14-2012, 07:35 AM   #61
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Intersting...

Question is- why do people want a FF sensor? I assumed it was a Pentax FF sensor.

So while I'm happy to use a K-5, a FF rival, I'd like Pentax to succeed. In order to succeed, a FF sensor dslr will help it business wise.

People are only interested in the techincal professional side of things?

02-14-2012, 08:23 AM   #62
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Why FF?

The question can be answered any number of ways..
Most of us would answer from an artistic perspective or a practical perspective.
The guy behind the counter told me there were more moving parts in my *ist than there were in a car. People think they know stuff about camera technology and can discuss it intelligently, but it's not necessary you just have to understand the results.. and to understand the results , you just have to look at the pictures. I remember a classroom discussion of why you should understand in which direction your shutter curtain moves.. with a few practical examples. Like a lot of technical discussion, it was relevant to very few people. You want to understand these things, but really there's this hierarchy... users, repair technicians, manufacturers, designers. Really, unless you're a designer, you really don't have an opportunity to understand the effects of the specific technical variations in design. I'd love to be here with a room full of camera designers from Nikon, Canon etc. but I probably wouldn't understand what they were talking about, same with lens designers. The mind of Jun Hirakawa is a mystery to me. When you see people talking here, they are illustrating basic technical points that affect how we shoot. But there is no in depth technical discussion... nor could there be. We know nutsink. When you're talking about the interaction between lens and sensor design in a camera system.. really most of us don't even know what the working parameters are.

Really most of us just want few ideas that might help us take good pictures. The technical is just blah blah blah to make you think we know what we're talking about. I swear a lot of the tech stuff I read on here is more likely just as likely wrong than right, even stuff I write. Wrong in that it's a gross over simplification to make a point, that ignore other information critical to that point, which may be just as relevant. For example the notion that an FF sensor will alway be better in low light that an APS-c because of the large sensor size and collecting more photons at each sensor location. That whole assumption is so fraught with peril that I can only accept it as a description of a situation at a specific point in time. It's possible someone will come up with amore sensitive sensor, that performs in low light better than an FF sensor, and it''a also possible that it may only be available on an APS-c sensors. AT that point the whole previous assumption, while technically correct would be practically wrong, so of what value is it? It's never all about the science.

After being asked "Why FF"

You can do a cost analysis.
You can talk image quality.
You can talk technique, because when you have tilt and swivel fronts and backs there are techniques available to you not available with fixed cameras, and technique overcomes many technial limitations.
You can talk looks or ease of use
You can talk technical specs. and performance.

All are relevant, of those the least relevant is the technical analysis. I don't have to understand how an internal combustion engine works to drive a car. I need to know how to turn on the ignition and work the controls. That's all you need to know to be a photographer. You can get quite good just playing around with the camera seeing what it can do for you. You cannot however become a good photographer by engaging yourself with technical specs. anymore than you can become a good tennis player by learning about the tensile strength of carbon fibre rackets. I had one half hour a course in lens design..and 10 hours a week in studio and 10 in the darkroom. In terms of time allocated, technical english was more important than the technology of the camera. And after I left I believe the lens design course was cancelled. At some point someone realized that while it might help you as a photographer to understand lens design, realistically, they were probably wasting our time. And people who could have been quite good photographers were washing out because they didn't get their lens design credit.

Last edited by normhead; 02-14-2012 at 08:57 AM.
02-14-2012, 08:52 AM   #63
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Well I'm curious how that new Nikon D4 and Canon 1Dx are going to perform. Both will have newest technology and can be put next to D800 and K-5.

These two camera's have the same score: K-5 and D3s both score 82 points.
DxOMark - Compare cameras side by side
I was standing next to one at the final in EC Waterfly with my K-5 and DA*300mm and him the D3s and 400mm/f2.8 with 1.4x TC. So that are a lot of differences, but believe me: You do get a bonus for slapping down so much money. Our FOV corrected for the more pixels of the K-5 are almost the same. At iso 3200-6400 the D3s outperformce the K-5 by a big margin.

QuoteOriginally posted by Class A Quote
Commonly quoted but non-existent advantages for FF include
  • lower noise: A larger sensor does not have less noise. A noise advantage is indirectly enabled by bullet 3. above.
  • bigger pixels: First, sensor size is independent from pixel size. Second, pixel size does not matter. "Fat" pixels do not perform better than small pixels.
Well I would like the same count in pixels but would like bigger pixels, meaning that the sensor has to grow.

QuoteOriginally posted by Class A Quote
Larger sensor do not have a reach disadvantage. Pixel pitch counts, not sensor size.
Again, keeping my pixelcount. I don't understand why people would want to buy a camera with 36 megapixel, to only use 16 megapixel of them. I want to use all the pixels I can afford and slap a lens on that camera that brings me the FOV I'm looking for.

QuoteOriginally posted by beholder3 Quote
Then the crop disadvantage on wide angle is 100% counterbalanced on the tele side even by theory (if image quality is the same as is the case, see above referral to example pictures on dpreview).
I might add that some cheap wide angles on F may save you 80$, but extra 200mm on the long end may cost you 4000$ extra...
This is my most important point. I want improvement in image quality for photographing in the telerange, but I'm not willing to pay all the downsides to it (more expensive and more heavier lenses).

Of course this is of no matter for the people who are looking for the excellent camera to use for macro, micro, portrait, landscape, family and holiday pictures. This is important for everyone who wants to do fast active sports or wildlife photography.
02-14-2012, 09:49 AM   #64
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for me, I just want all my glasses to show their real FoV. Imagine 43mm to have the real FoV is just a beauty.

02-14-2012, 11:04 AM   #65
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QuoteOriginally posted by Class A Quote
Commonly quoted but non-existent advantages for FF include
  • lower noise: A larger sensor does not have less noise. A noise advantage is indirectly enabled by bullet 3. above.
This paper concludes that "Rather than having strong dependence on the pixel size, the noise performance instead depends quite strongly on sensor size -- bigger sensors yield higher quality images, by capturing more signal (photons)."

Jeff
02-14-2012, 11:31 AM   #66
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Ya, what that guy said...


or to paraphrase.. if you have the same pixel count an FF and APS-c and you cut the image size on teh APS-c in half, you'll get just as clear an image but one quarter the size... the only thing that makes a difference is the overall number of photons captured, and larger sensors capture more photons, oh ya and 14 bit isn't really an advantage over 12 bit in APS-c because of noise.

But if this sensor comes out in APS-c but not full frame, you have to wonder if it would bring APS-c photon capture up to the level of FF. Based on the FF images I've seen, I'm not sure they can be any sharper, APS-c has room for improvement. You'd have to know how many photons are out there to be captured, how many get reflected around and become noise, what the theoretical optimum sensor size is etc etc. It's better not to think so much it hurts your brain.
Just take pictures, put them up on your screen and say "I like that one." That's what I like to do.

The sensor below should improve photon capture and reduce noise... but what other factors might prevent that from happening? It's never proven until it's proven.



I'm guessing the circuit area of older sensors are a majour source of noise.

Last edited by normhead; 02-14-2012 at 11:48 AM.
02-14-2012, 12:49 PM - 1 Like   #67
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QuoteOriginally posted by RobG Quote
In my case, a 300mm lens having an effective focal length of 450mm is a big advantage where until now the availability of longer lenses for the brand is very limited.
As Coeurdechene explained (again), you are wrong if you think that APS-C buys you more "reach". You simply do not need to buy a new 500mm lens provided that the FF camera has sufficiently many MP.

Did you read my respective post?

QuoteOriginally posted by RobG Quote
A reduction in digital noise and an increase in dynamic range would be nice, but in the short term I don't think I'm likely to see much better than the K5 (which I haven't bought yet).
The K-5's sensor scaled up to FF dimensions will be (>1 stop) better. Simple physics.

QuoteOriginally posted by RobG Quote
If a FF sensor has the same pixel pitch as the APS-C you have negated one of the main arguments for a FF sensor - larger sensor elements. If you are just making a bigger sensor with more elements, you won't gain anything in terms of noise reduction.
Larger sensor elements
  • are not the motivation for FF sensors
  • do not help with image noise.
You are of course entitled to your own opinion on whether or not FF is useful for you, but currently you are basing your decision on incorrect assumptions.

QuoteOriginally posted by RobG Quote
Maybe I'm not appreciating the complexities of accommodating a new sensor but if the sensor was available I wouldn't have thought adapting an existing body to it would be so hard.
There is a lot more involved in upgrading a camera model to FF. Mechanics do not always scale up easily and electronics need to be adapted in order to cope with more image data (assuming we are not talking about 12 or 16MP).

QuoteOriginally posted by RobG Quote
From what I've read elsewhere, a suitable sensor isn't available and Ricoh doesn't have the means to develop one.
There is little reason to believe Sony wouldn't make their FF sensor(s) available to Pentax as well.

Last edited by Class A; 02-14-2012 at 12:56 PM.
02-14-2012, 01:05 PM   #68
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QuoteOriginally posted by RonHendriks1966 Quote
Well I would like the same count in pixels but would like bigger pixels, meaning that the sensor has to grow.
What do you want bigger pixels for?
They will help with (irrelevant) pixel noise but as far as the (relevant) image noise is concerned, smaller pixels are not a disadvantage. On the contrary, smaller pixels will give you finer-grained noise. Please read the DxOMark article I linked to in an earlier post.


QuoteOriginally posted by RonHendriks1966 Quote
I don't understand why people would want to buy a camera with 36 megapixel, to only use 16 megapixel of them.
The thing is you only use 16MP when you want the reach, but you are free to use 36MP anytime.

The argument is that you don't lose any capabilities (e.g., tele reach) by going FF provided the camera has enough MP to allow cropping without resolution. The argument is not that you never use all MP.

02-14-2012, 01:16 PM   #69
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QuoteOriginally posted by Jeff Charles Quote
This paper concludes that "Rather than having strong dependence on the pixel size, the noise performance instead depends quite strongly on sensor size -- bigger sensors yield higher quality images, by capturing more signal (photons)."
They arrive at this conclusion because they are using the same f-stop for both sensor formats.

That's comparing apples to oranges, as the image on the larger sensor will have less DOF. It is a bit like saying "My image is brighter than yours (because I exposed 1.5 times longer than you)".

If you stop down the lens in front of the larger sensor in order to achieve the same DOF, this reduces the number of photons available to the sensor. Now both (small and large) sensors receive the same total amount of photons. The larger sensor has a larger surface but with the same amount of photons that only means that the photon density per sensor unit area decreases.

Larger sensors only have a noise advantage, if they receive more photons than smaller sensors. For instance, if they receive the same number of photos per unit area (i.e., if the exposure is the same). However, achieving the same exposure by using an f-ratio that yields shallower DOF is not fair. Using a different shutter speed would lead to a different image as well (in general). Hence the only way a larger sensor can make up for its need for more total photons, in order to achieve the same exposure, is to use a higher ISO setting.

There is still a low-light advantage to larger sensors as they can use lenses (e.g., 50/1.4) for which no APS-C equivalent (e.g., 33/0.9) exist. But it is the lens availability that creates the low-light advantage, not a property of the larger sensor.
02-14-2012, 01:39 PM   #70
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Class A, you linked to an article showing that higher pixel counts reduced the appearance of image noise, so it follows that a full frame sensor at the same pixel pitch as an apsc one will suffer less from image noise if you bump the iso... thus evening things out.

QuoteOriginally posted by Class A Quote
smaller pixels will give you finer-grained noise. Please read the DxOMark article I linked to in an earlier post.
No the article doesn't say that. What it says is that 'moar megapixels' will reduce the appearance of noise (once the image has been downsampled for printing at a given size). The examples given are of two cameras of similar pixel pitch (and presumably pixel size?) - an 8MP APSC camera vs a 21MP FF camera.

QuoteOriginally posted by Class A Quote
There is still a low-light advantage to larger sensors as they can use lenses (e.g., 50/1.4) for which no APS-C equivalent (e.g., 33/0.9) exist. But it is the lens availability that creates the low-light advantage, not a property of the larger sensor.
A 1.4 lens is a 1.4 lens and transmits the same amount of light irrespective of whether a smaller sensor affects the apparent depth of field. You seem to be putting the cart before the horse in your example - the advantage (to FF) is in dof control, not light gathering ability. The advantage is that you can use pretty humdrum lenses with moderate apertures and achieve nice subject isolation through DOF - e.g. a 50mm f2, which you would need something like a 30mm f1.4 to replicate on APSC. Such lenses are available (e.g. the Sigma 30mm) but are a lot bigger and more expensive than what they aim to replicate.

People have mentioned 'how much dof control do you really need?' One example stated that the need to keep the whole of a subject's face in focus means even on APSC he has to stop down a bit anyway. That is true, but as you move away from the subject dof increases and you need to open up the aperture more and more if you want to make them pop out three dimensionally. Also, you may wish to allow parts of the subject's face to drift slightly out of focus intentionally, depending on the style you are going for.

Last edited by ihasa; 02-14-2012 at 02:15 PM.
02-14-2012, 01:47 PM   #71
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QuoteOriginally posted by RobG Quote
I'm sorry if this subject has been talked to death and I can't find the thread. I've seen lots of people complaining about the fact that Pentax hasn't brought out a Full Frame (FF) sensor camera, but I don't understand why. My apologies that I'm missing the point, but please educate me, don't abuse me. Once upon a time I loved 35mm film, but now I can get great results with an APS-c digital SLR, and the sensor size is an advantage because it makes the effective focal length of a telephoto lens longer; handy when the longest Pentax lens freely available is only 300mm (well, until the recently announced 560mm ). I'm not at all bothered by the dimensions of the sensor in me K7 or K200. I'm more frustrated by being unable to get a digital image out of my old negs and slides as good as was possible printing them directly onto paper (and yes, I know there's lots of technical reasons for that).

So why would a camera with a 35mm film frame sized sensor be better than one with a smaller sensor?

PS If asking this question really bothers people, I'll delete the thread, but I'd like to know the answer to the question.

For me , i want it to pair with my 50mm f1.2, mostly for DOF reasons, thats all.

For me:

Not a matter of if FF is better than APC or not, it is something I want, it is not one of my needs.


The only reason I do not buy sony a900 is that i can not use my k lenses with it. Sony makes the cameras i want and pentax has the lenses i want.
02-14-2012, 02:04 PM   #72
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QuoteOriginally posted by Class A Quote
What do you want bigger pixels for?
They will help with (irrelevant) pixel noise but as far as the (relevant) image noise is concerned, smaller pixels are not a disadvantage. On the contrary, smaller pixels will give you finer-grained noise. Please read the DxOMark article I linked to in an earlier post.

The argument is that you don't lose any capabilities (e.g., tele reach) by going FF provided the camera has enough MP to allow cropping without resolution. The argument is not that you never use all MP.
I read the article. I'm a patient guy. So I wait to see new DxO tests for D4, 1Dx and D800 and then we can make new conclusions.

My interest is better image quality for iso-settings 1600 and up!
02-14-2012, 02:21 PM   #73
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My interest is pretty much entirely because of dof control, as you'd have guessed from my comments above!

However I am not obsessed about full frame, because I do like the existing lenses and bodies Pentax offer, and shallow dof shooting is certainly not the be-all-and-end-all of my photography.

When I look through threads of images like this though, which almost certainly contains FF images judging by the clarity and subject isolation, I do feel tempted though! However of course most of the quality there is because of the subject matter and the photographer's skill. I'm not remotely at that level yet, and until I am, I will content myself with trying to get a similar look through fast lenses like the Sigma 30/1.4, Samyang 85/1.4 etc.
02-14-2012, 02:45 PM   #74
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QuoteOriginally posted by ihasa Quote
Class A, you linked to an article showing that higher pixel counts reduced the appearance of image noise, so it follows that a full frame sensor at the same pixel pitch as an apsc one will suffer less from image noise if you bump the iso... thus evening things out.
Let's not quibble about the details of what you said, but in general it is true: In terms of noise, the need to bump ISO on a larger format is cancelled out by its lower enlargement factor (or vice versa). I've never said anything else.

QuoteOriginally posted by ihasa Quote
No the article doesn't say that. What it says is that 'moar megapixels' will reduce the appearance of noise (once the image has been downsampled for printing at a given size).
The properties "more MP" and "smaller pixels" are equivalent if you keep the sensor size constant.

QuoteOriginally posted by ihasa Quote
The examples given are of two cameras of similar pixel pitch (and presumably pixel size?) - an 8MP APSC camera vs a 21MP FF camera.
The change in sensor size is an unnecessary change of a variable used only in the beginning of the article. Once you consider the different enlargement factor, the pixels on a print of the 21MP camera are indeed smaller than those of the 8MP camera. But again, I don't think that changing both sensor size and pixel count at the same time is a good idea to illustrate the point they are trying to make.

Note that the comparison table only contains cameras with the same sensor size (i.e., the "more MP" directly translate to "smaller pixels").



QuoteOriginally posted by ihasa Quote
A 1.4 lens is a 1.4 lens and transmits the same amount of light irrespective of whether a smaller sensor affects the apparent depth of field.
The larger sensor will collect more photons (all those that are outside the area captured by the smaller sensor). Thus, not only DOF but also the total amount of light gathered changes. BTW, DOF and exposure are inseparably linked. You cannot have thinner DOF without collecting more light or deeper DOF without collecting less light. It is precisely the additional amount of light that creates the fuzziness needed for shallower DOF.

QuoteOriginally posted by ihasa Quote
You seem to be putting the cart before the horse in your example - the advantage (to FF) is in dof control, not light gathering ability.
That's what I said all along (see my first post).

Nevertheless it is true, that FF can be advantageous for low-light shooters. It is a fact that there are FF lenses which will allow you to create shallower DOF than with any APS-C lens available (for a given AOV). This is just another way of saying that there are FF lenses which will help you in low-light situations which have no APS-C equivalents (for a given AOV).

Last edited by Class A; 02-14-2012 at 02:58 PM.
02-14-2012, 05:03 PM   #75
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Getting back to basics... why want a FF camera? Well, why would Nikon and Canon produce FF cameras if their APS-Cs were enough for all their photographer client base? After all, the D300 and 7D have very, very good autofocus and excellent results - 18Mp of it on the 7D. How many photographers, even pros, need more than 18Mp? Why are their FF sales so successful if these high end APS-C offerings were enough? That's the demand end of the argument for FF.

Teasing out some more of the practical reasons for the Pentax FF, we have the potential to gain a significant deal more DOF control and larger area for data collection, thereby creating smoother high ISO results - I believe jsherman999's thread on Full Frame shots and thoughts discusses the benefits well. So there is no doubt there are real and practical reasons for wanting a Pentax FF, but as we know, we just have to wait...
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