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08-27-2010, 02:06 PM   #676
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QuoteOriginally posted by falconeye Quote
I'd like to add an argument to the chicken and egg situation we're still facing here.

2. A new element adding to the discussion:

One reason why FF sensors are more expensive when not volume-produced is that the photoreticle (and stepper widths) weren't made large enough in the first place. Typical values go to up to 22x30mm. But larger reticles can be manufactured if justified by volume. By consequence, FF sensors are stitched which adds to the cost. A photoreticle is a phase shift glass plate with a complex pattern.
Somehow, but maybe I'm not the smartest one in the world I see a nice sensor size.: 22x30mm ! How much room do we loose on the side, 0,5 mm so the actual size of the sensor would be 21x29mm and with 6 micron pixels you get 3500 x 4833 = 16,9 megapixel with great quality.

That would be a great thing to have in my opinion and maybe even the cheaper way productionwhise.

08-27-2010, 02:51 PM   #677
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Yet another sensor size discussion?

It should be vigorous, if a bit redundant. I'll check back later. Someone else will write what I'm thinking except a whole lot better. That's what practice will do.
08-27-2010, 03:02 PM   #678
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QuoteOriginally posted by glanglois Quote
Yet another sensor size discussion?
It should be vigorous, if a bit redundant. I'll check back later. Someone else will write what I'm thinking except a whole lot better. That's what practice will do.
After 46 pages, I'm sure someone already has...
08-27-2010, 03:22 PM   #679
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QuoteOriginally posted by m8o Quote
After 46 pages, I'm sure someone already has...
My point exactly !!

08-27-2010, 03:24 PM   #680
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QuoteOriginally posted by m8o Quote
After 46 pages, I'm sure someone already has...
It would be nice if threads like these could be merged or made as a "sticky" at the top of the thread, that way you won't have 2-3 threads on the exact same topic going back and forth in the forum.

You could have the "Perpetual Pentax FF thread 2010-2011" stuck to the top of the News and Rumors forum. People could talk about viewfinders, sensor size, economics and the camera market ad nauseum without having to start a new thread every time a new detail comes up.
08-27-2010, 03:55 PM   #681
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QuoteOriginally posted by Rondec Quote
The different sensors stress lenses in different ways. Full frame sensors stress lenses in their corners a lot more and that is where "cheap" lenses suffer the most anyway. APS-C crops out those corners and extreme borders, but puts a lot more stress on the center of a lens.
Yes, however what you're ignoring is that FF sensors stress the lenses in an area that is essentially of no importance in actual photos 99% of the time (i.e., if you pull up a random sample of 100 images, I'd be shocked if you could find 5 that would suffer any genuine degradation as photos, in their entirety, if whatever is in the far corners of the image is not razor sharp). APS-C, on the other hand, puts a great deal more stress on the lens where it counts - in the middle of the lens where the primary points of interest in 99% of photos is, which means APS-C stresses lenses in a way that actually is detrimental to actual photos. Only in "lens test land" or in the APS-C marketing "talking points" does "corner sharpness" mean a damn thing 99% of the time.

An APS-C dSLR compared with a FF dSLR must resolve the same details at about 42.25% of the size as does the FF dSLR (in the case of Pentax, Canon APS-C, for example, is even smaller). That is MUCH more demanding of lens resolution, and is much more demanding where it counts.
08-27-2010, 04:20 PM   #682
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24X36NOW, you've just made the most cogent argument against 24x36 I've read to date! ...if one is apt to frame following the 'rule of thirds'.

If one frames the primary subject on one of the 'rule of thirds' intersection line, that point on a cropped sensor's view finder is in a 'higher sharpness & resolution' location of the lens, as the projected image thru the lens hitting the sensor is closer to the center. The FF sensor making use of more of the lens's area places those virtual intersecting points on the sensor in a location of the projected image through the lens that is further from the center.

Not what you were intending... hahahaha... Of course, I largely kid. The resolution of the difference between the projected rule of thirds line on to the cropped sensor vs a FF sensor is splitting hairs; the distance is quite close so the resolution hasn't dropped of all that much between one and the other.

Last edited by m8o; 08-27-2010 at 04:27 PM.
08-27-2010, 04:45 PM   #683
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QuoteOriginally posted by m8o Quote
QuoteQuote:
Originally posted by glennm
The benefit of FF is that you can hang so-so glass on the camera and make images superior to APS-C systems with the best glass.
RE: To anyone in the know in the peanut gallery... is this true?
Many replies already. My 2cts at this go as follows:


The statement is an exaggeration but not entirely false. It is easy to see because there are two effects both working in the same direction
  1. The larger sensor has a lower lp/mm requirement for the same LW/PH resolution. E.g., 3000 LW/PH translate to 94 lp/mm on APS-C but only 63 lp/mm on FF. And because the registration distance is constant, the potential benefit of having the rear lens closer to the sensor (which would help to achieve the higher lp/mm) is unavailable.
  2. Worse even, to achieve 63 lp/mm with an f/4 lens may be straight-forward while to achieve the same with the APSC-equivalent of f/2.8 is much harder. And of course, you don't have to achieve the same but better because of (1).
This is why equivalent FF lenses tend to be cheaper and ultimately, why APSC systems (body+lens) will become more expensive than FF. Some day. It's also a reason why the superb 645 lenses now resolving 40MP on a 645D aren't expensive actually.

I touched at this topic a bit in my article this thread once was supposed to be about

As for corner sharpness and vignetting: It only makes a difference for wide angle lenses but to make an equivalent APSC wide angle lens is more challenging in the first place. Imagine an equivalent 21mm f/1.2 for the FA31Ltd. If it would be feasible, one thing is for sure: the corners would not vignette less

08-27-2010, 05:48 PM   #684
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QuoteOriginally posted by glennm Quote
my point is that ff would let my old lenses perform as they were engineered to..
That's not really true. Using them on a film camera would let them perform as they were engineered to, since that's what they were engineered for.
08-27-2010, 05:59 PM   #685
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QuoteOriginally posted by 24X36NOW Quote
Yes, however what you're ignoring is that FF sensors stress the lenses in an area that is essentially of no importance in actual photos 99% of the time
I think you are marginalizing landscape/architecture photography and other such genres where you'd like full resolution up into the corners.

QuoteOriginally posted by 24X36NOW Quote
APS-C, on the other hand, puts a great deal more stress on the lens where it counts - in the middle of the lens where the primary points of interest in 99% of photos is,
  1. snapshots have their interest right in the centre, most more ambitions images do not
  2. APS-C puts "more stress" on all parts of the image, not just the centre. What you are saying only makes sense for the situation where FF-glass is used on an APS-C camera.
FF-glass on APS-C camera doesn't need to perform well in "FF-corners" as they are not captured. Everything captured has to stand up to crop-factor x more enlargement. If you are considering APS-C glass on an APS-C camera the "putting more stress on the centre" argument goes away (and is replaced by the worse "putting more stress on all of the image area")

QuoteOriginally posted by 24X36NOW Quote
which means APS-C stresses lenses in a way that actually is detrimental to actual photos.
This applies to FF-glass on crop cameras only and it depends on the photo and the lens whether it is better to lose weak corners or to have less enlargement of the whole image.

QuoteOriginally posted by 24X36NOW Quote
Only in "lens test land" or in the APS-C marketing "talking points" does "corner sharpness" mean a damn thing 99% of the time.
In FF-land "corner sharpness" doesn't mean a thing because you cannot see the corners due to vignetting anyway. Sorry, I just like that joke too much to not use it whenever I can.

QuoteOriginally posted by 24X36NOW Quote
An APS-C dSLR compared with a FF dSLR must resolve the same details at about 42.25% of the size as does the FF dSLR.
I regard this as dramatisation as we are not looking at dynamic range here where area matters, but at resolution which is typically expressed in one dimension only. So the the more appropriate percentage is 65%. That times the crop-factor (1.54 here) gives you 100% and you don't want to enlarge an APS-C image to more than a 100% of the FF-image on each side.

BTW, a larger sensor doesn't have an "enlargement advantage" if the pixel-pitch is reduced compared to a smaller sensor. I don't see the allure of a 12MP FF sensor at all: A K-7 has more resolution than that and larger pixels don't result in a high-ISO advantage. The one thing such a "low-res" sensor buys is speed. Reading out fewer pixels and processing/storing smaller images helps to crank up the FPS rate.

Last edited by Class A; 08-27-2010 at 06:24 PM.
08-27-2010, 07:21 PM   #686
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I wonder if any of the I have to have a full frame camera crowd have ever just thought about buying one? There are other options like Canon, Nikon, Leica, and Sony (at least for now). All very good camera manufacturers. Make yourself happy, get what you really want instead wishing for something that doesn't appear to be happening anytime soon. I really wanted a mirrorless camera. Pentax didn't make one so I bought an Olympus. I know a lot of people who use more than one camera system. I use a Leica and a Rollei for film. No reason you only have to have one brand. I think you can use Pentax lenses on Canon cameras with the proper adapter.
08-27-2010, 07:48 PM   #687
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Im just so over this stupid discussion, it's not going to change anything.

I'm laughing when I read people talking about wanting Camera companies to go backwards and use 12mp sensor it won't happen so get over it.

None of you armchair critics are camera or sensor designers, engineers, etc your just a pack of armchair critics.

FF won't instantly make any of you better photographers, nor will having the ability to shoot at 16,800 noise free, nor will ... oh stuff it you get the idea?

Some of the worlds best works have been pulled off with less than stellar equipment, at the end of the day its about the photographer and what he does with his equipment, not about the equipment on its own.

Other things with people demanding FF here, how many of you are willing to pay the money for a Pentax FF? from many comments I read not many want to spend more than half the price of a 5D MkII.

But final thoughts and musings:

* The K-5 is APS-C DSLR, not an EVIL, not a FF or anything else so quit the speculating and false rumor mongering.

* FF is coming but not for a while, I've confirmed this with multiple sources.

Start you own camera companies or buy another system and give it a rest.

It's making this forum especially this section unbearable to venture into.

Last edited by Christopher M.W.T; 08-27-2010 at 08:05 PM.
08-27-2010, 09:17 PM   #688
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QuoteOriginally posted by Christopher M.W.T Quote
...It's making this forum especially this section unbearable to venture into.
People who live in glass-houses....

I wonder what everyone is going to do after Photokina? This whole forum will fall silent, probably. It will be like a ghost town.
08-27-2010, 09:20 PM   #689
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QuoteOriginally posted by rawr Quote
People who live in glass-houses....

I wonder what everyone is going to do after Photokina? This whole forum will fall silent, probably. It will be like a ghost town.
Lol........
08-27-2010, 09:47 PM   #690
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QuoteOriginally posted by falconeye Quote
1. The larger sensor has a lower lp/mm requirement for the same LW/PH resolution. E.g., 3000 LW/PH translate to 94 lp/mm on APS-C but only 63 lp/mm on FF. And because the registration distance is constant, the potential benefit of having the rear lens closer to the sensor (which would help to achieve the higher lp/mm) is unavailable.
2. Worse even, to achieve 63 lp/mm with an f/4 lens may be straight-forward while to achieve the same with the APSC-equivalent of f/2.8 is much harder. And of course, you don't have to achieve the same but better because of (1).


This second point is true, is often overlooked, and is really hitting home for me lately in my general shooting.

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