Cross platform equivalency

Started 8 months ago | Discussions
Rick Knepper
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Cross platform equivalency
8 months ago

FF > MF that is.

Yes this will concern a rumored Canon camera, not an actual one (at least for the moment).

I am pretty comfortable in my understanding that more MPs per given area results in more detail.

Let's say this rumored camera, casually referred to on this forum as the High Resolution Monster, has 51 MPs just like the Pentax 645Z.

Those same number of MPs will be laid out on .79x less area on Canon's FF sensor as opposed the Pentax sensor.

I have admitted in the past that I am fuzzy on cross platform equivalency but until now I have not been interested in anything but FF. The Pentax 645Z may change that.

Noise and DR aside, which set of 51 MPs will produce more detail, less detail or the same detail in the respective systems all other things being equal?

GB mentioned large pixel blur the other day so I am interested if that concept applies here in any way since the pixels on the Pentax sensor will be larger.

Anyone not familiar with the Pentax 645Z can catch up here:

http://www.dpreview.com/news/2014/04/15/hands-on-with-the-pentax-645z?utm_campaign=internal-link&utm_source=mainmenu&utm_medium=text&ref=mainmenu

The pros of the 645Z, $8499, 51 MPs. on a sensor larger than FF, weather sealed, 25 cross-type AF points, and wait for it.............. articulating LCD.

The cons: 3 fps.

Lenses for the system mostly look reasonably priced although you won't find any pity-fifty pricing. The MF>FF crop factor is .79 according to DPR.

http://www.bhphotovideo.com/bnh/controller/home?O=&sku=1045517&gclid=CMOVld_K5L0CFdBcMgodCCkAGA&is=REG&Q=&A=details

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qianp2k
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Re: Cross platform equivalency
In reply to Rick Knepper, 8 months ago

645Z and associated lenses certainly are attractive to some Pros and enthusiasts who want to pursue the best IQ as possible while still relative affordable and portable. A rumored Sony mirrorless fixed-lens MF on the same sensor with EVF in a RX1-typed body (much lighter/smaller than 645Z) and priced at $5K or below will be also a great option for those groups of photographers.

However I believe most Pros and enthusiasts will stay on FF as the best balance of IQ and portability/cost/weight/size/lens choice.

Separately I agree unless there is a dramatically improvement in sensor QE, you'd have to increase sensor size for much better IQ.  Larger sensor -> better IQ on the same QE of sensors, a simple law of physics.

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Silverback1988
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I believe it's a hard task for Canon to equal the MF.
In reply to Rick Knepper, 8 months ago

Hi Rick,

Rick Knepper wrote:

FF > MF that is.

Yes this will concern a rumored Canon camera, not an actual one (at least for the moment).

It's still fun to speculate a rumored Camera.

I am pretty comfortable in my understanding that more MPs per given area results in more detail.

Yes, if the glass allowed I believe.

Let's say this rumored camera, casually referred to on this forum as the High Resolution Monster, has 51 MPs just like the Pentax 645Z.

Those same number of MPs will be laid out on .79x less area on Canon's FF sensor as opposed the Pentax sensor.

It will be a stretch for the FF glass to match the MF glass. I don't know the crop factor exactly,

so I just take your number, 0.79 it is.

The FF glass need to be 1.26 x sharper at 0.79x f ratio from the MF lens to match exactly what MF system is producing.

ie. the MF is at 80mm f/4  --->  FF is at 64mm f/3.2  and the FF lens must be 1.26 times sharper than the MF lens at that setting.

If the Canon could do that, so it will be less point to go MF.

I hope Great Bustard will join in. He is good with numbers

and also good with hypothetical condition

I have admitted in the past that I am fuzzy on cross platform equivalency but until now I have not been interested in anything but FF. The Pentax 645Z may change that.

I hope the Pentax will make other company lower their price

Or...  I will start saving my money for the Pentax 

Noise and DR aside, which set of 51 MPs will produce more detail, less detail or the same detail in the respective systems all other things being equal?

GB mentioned large pixel blur the other day so I am interested if that concept applies here in any way since the pixels on the Pentax sensor will be larger.

I think GB talk about the same format, the larger pixel means less MP.

Thus it doesn't apply here on the Pentax's 51 MP vs Canon 51 MP FF.

Anyone not familiar with the Pentax 645Z can catch up here:

http://www.dpreview.com/news/2014/04/15/hands-on-with-the-pentax-645z?utm_campaign=internal-link&utm_source=mainmenu&utm_medium=text&ref=mainmenu

The pros of the 645Z, $8499, 51 MPs. on a sensor larger than FF, weather sealed, 25 cross-type AF points, and wait for it.............. articulating LCD.

yes, articulating LCD !!

The cons: 3 fps.

Not a problem for me. Even 1 fps will make me happy, as long I got the discount in price

Lenses for the system mostly look reasonably priced although you won't find any pity-fifty pricing. The MF>FF crop factor is .79 according to DPR.

http://www.bhphotovideo.com/bnh/controller/home?O=&sku=1045517&gclid=CMOVld_K5L0CFdBcMgodCCkAGA&is=REG&Q=&A=details

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Rick Knepper, photographer, shooting for pleasure. It is better to have It and not need It than need It and not have It. Various RAW comparisons at Link below. Includes 5D3 vs D800E (new uploads), 5D3 vs. 6D, Zeiss lenses etc. https://app.box.com/s/71w40ita6hrcfghojaie

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Brian

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Keith Z Leonard
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Re: Cross platform equivalency
In reply to Rick Knepper, 8 months ago

If you have read any of the several thousand crop vs 35mm arguments over the years it's all the same stuff applied to MF vs 35mm.  I have been pointing out for years that this is the case, that for some reason people have decided that 35mm is the "perfect" balance of price/performance, which really means they can afford 35mm.  If money is not an object and there exists something better, well, you see where I'm going with this.

The issue has been that crop and 35mm really have been the sweet spot in terms of selling cameras to people, so they have enjoyed the most focus on tech advancement.  With all of the talk about DSLR saturation you might start to see more MF cameras like the Pentax who target working pros who can afford then and are seeking something to differentiate themselves from the mom/dad with a camera crowd.

Anyway, to the crop stuff.  1.27 or so crop factor means that we are comparing a difference pretty close to the difference between 35mm and APS-H.  If the sensors are of the same tech generation you will get better images from the 51mp MF sensor, all other things being equal.  You will get thinner depth of field from the MF as well, which seems to be a key argument among the anti-crop movement.

The real question comes down to whether or not you need it.  The d800's 36mp is interesting, I personally don't need it for what I want to do.  I usually don't need 20mp either, if I'm being honest.  All of these arguments about getting the best hardware often makes a pretty insignificant difference to your average photo, it's more about the outlying images that make people go ooo and aaaa.

Summation, the Pentax images SHOULD be better than a Canon 35mm with the same pixel count, due to larger surface area, all things being equal.  Does that justify the cost difference that we'll likely see?  Hard to say as the Canon camera doesn't exist.  Are there other features of the Canon that make it a better fit for your uses??  Again, hard to say.

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qianp2k
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Re: Cross platform equivalency
In reply to Keith Z Leonard, 8 months ago

Keith Z Leonard wrote:

If you have read any of the several thousand crop vs 35mm arguments over the years it's all the same stuff applied to MF vs 35mm. I have been pointing out for years that this is the case, that for some reason people have decided that 35mm is the "perfect" balance of price/performance, which really means they can afford 35mm. If money is not an object and there exists something better, well, you see where I'm going with this.

Yes similar comparison but in higher diminishing return. 645Z is 0.78x crop that makes 35mm FF sensor roughly 1.3x crop to this MF sensor (which itself a crop MF sensor compared to bigger CCD MF sensor in PhaseOne IQ280 and Mamiya 645DF). You only see noticeable difference when you print/view in very big size. Bear mind mind that it seems true Sony 54mp sensor and a high pixel Canon sensor are coming.

The issue has been that crop and 35mm really have been the sweet spot in terms of selling cameras to people, so they have enjoyed the most focus on tech advancement. With all of the talk about DSLR saturation you might start to see more MF cameras like the Pentax who target working pros who can afford then and are seeking something to differentiate themselves from the mom/dad with a camera crowd.

That's the point that FF cameras are sweet spot, mature enough with most features, and affordable enough in these days, more and most versatile lens choice. Also much lighter and smaller and lots cheaper. Nevertheless this 645Z makes a MF relative affordable to some Pros and enthusiasts who pursuing the best IQ on still  relative affordable price.

Anyway, to the crop stuff. 1.27 or so crop factor means that we are comparing a difference pretty close to the difference between 35mm and APS-H. If the sensors are of the same tech generation you will get better images from the 51mp MF sensor, all other things being equal. You will get thinner depth of field from the MF as well, which seems to be a key argument among the anti-crop movement.

As said in higher diminishing return. DOF is not really an issue on equivalent DOF. FF f2.8 is eq to 645Z's f3.5.

The real question comes down to whether or not you need it. The d800's 36mp is interesting, I personally don't need it for what I want to do. I usually don't need 20mp either, if I'm being honest. All of these arguments about getting the best hardware often makes a pretty insignificant difference to your average photo, it's more about the outlying images that make people go ooo and aaaa.

Someone needs it but I am sure less need 645 than FF especially when Sony and Canon if released 50mp FF cameras in later this year. Not sure how good of DR in this 51mp Sony MF sensor, still 14-stop or 16-stop?

Summation, the Pentax images SHOULD be better than a Canon 35mm with the same pixel count, due to larger surface area, all things being equal. Does that justify the cost difference that we'll likely see? Hard to say as the Canon camera doesn't exist. Are there other features of the Canon that make it a better fit for your uses?? Again, hard to say.

More meaningful if this 51mp MF sensor compares to forthcoming 54mp FF sensor from Sony (if the rumor is true that at least as good as current 36mp sensor in other aspects) or on Canon 40+ mp sensor (we have no idea how good of Canon sensor). I suspect unless you use best of best MF prime lenses and print/view in extreme big size, the difference is not that big. I have no ideas of MF lenses (except they are very expensive), are some of them  as good as Otus 55/1.4, FE 55/1.8, Sigma 50/1.4 A and Sigma 35/1.4 A respectively?

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Keith Z Leonard
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Re: Cross platform equivalency
In reply to qianp2k, 8 months ago

qianp2k wrote:

Yes similar comparison but in higher diminishing return. 645Z is 0.78x crop that makes 35mm FF sensor roughly 1.3x crop to this MF sensor (which itself a crop MF sensor compared to bigger CCD MF sensor in PhaseOne IQ280 and Mamiya 645DF). You only see noticeable difference when you print/view in very big size. Bear mind mind that it seems true Sony 54mp sensor and a high pixel Canon sensor are coming.

Yeah, we're saying the same thing here.  35mm is the perfect balance due to both market forces and people's willingness to carry weight around.  The 645Z looks pretty reasonable in size though, honestly.

That's the point that FF cameras are sweet spot, mature enough with most features, and affordable enough in these days, more and most versatile lens choice. Also much lighter and smaller and lots cheaper. Nevertheless this 645Z makes a MF relative affordable to some Pros and enthusiasts who pursuing the best IQ on still relative affordable price.

MF is used by a good number of pro's still, and it used to be the standard for pro wedding, etc....it could get there again if there's enough interest in the market.  I think that's the swing market here, trying to get MF to compete again with 35mm for weddings would be a big win, as they've lost that market.  MF has been mostly relegated to pro landscapes and some portrait work (there are some that still insist on MF in that segment).

Anyway, to the crop stuff. 1.27 or so crop factor means that we are comparing a difference pretty close to the difference between 35mm and APS-H. If the sensors are of the same tech generation you will get better images from the 51mp MF sensor, all other things being equal. You will get thinner depth of field from the MF as well, which seems to be a key argument among the anti-crop movement.

As said in higher diminishing return. DOF is not really an issue on equivalent DOF. FF f2.8 is eq to 645Z's f3.5.

Eh, it's an arbitrary line though, some people feel the 1.3x difference between aps-h and 35mm is a big deal and some don't.  It almost becomes a religious argument, but really it depends upon what you are trying to do.

Someone needs it but I am sure less need 645 than FF especially when Sony and Canon if released 50mp FF cameras in later this year. Not sure how good of DR in this 51mp Sony MF sensor, still 14-stop or 16-stop?

I think I read a spec sheet on it that said 13 stops for the 645, no idea about unreleased Sony stuff.  High DR and MP sure would make for a great landscape camera though, Peter Lik is probably excited.  

More meaningful if this 51mp MF sensor compares to forthcoming 54mp FF sensor from Sony (if the rumor is true that at least as good as current 36mp sensor in other aspects) or on Canon 40+ mp sensor (we have no idea how good of Canon sensor). I suspect unless you use best of best MF prime lenses and print/view in extreme big size, the difference is not that big. I have no ideas of MF lenses (except they are very expensive), are some of them as good as Otus 55/1.4, FE 55/1.8, Sigma 50/1.4 A and Sigma 35/1.4 A respectively?

The lenses are larger, the pixel density is pretty close to that of D800, so you would expect better lenses like those you've listed are quite possible and can take advantage of the high pixel sensors.  The trick here is that while the others are rumors and as of yet vaporware this 645 actually exists, unless they pull a Canon and announced LONG before they were really in production.  Often getting to market first makes a far bigger difference than technical advantages/disadvantages.

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Rick Knepper
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Re: Cross platform equivalency
In reply to qianp2k, 8 months ago

qianp2k wrote:

645Z and associated lenses certainly are attractive to some Pros and enthusiasts who want to pursue the best IQ as possible while still relative affordable and portable. A rumored Sony mirrorless fixed-lens MF on the same sensor with EVF in a RX1-typed body (much lighter/smaller than 645Z) and priced at $5K or below will be also a great option for those groups of photographers.

However I believe most Pros and enthusiasts will stay on FF as the best balance of IQ and portability/cost/weight/size/lens choice.

There were some $8k FFs just a few years ago and there might be again if the "Monster" arrives cloaked in 1 Series clothing.

If the "Monster" arrives priced like a D800, then of course, the decision becomes exponentially more difficult - for me. I can sell all of my Nikon kit (aka my high res kit) and get close to the purchase price of the camera and maybe one lens. That will leave me with my entire Canon kit still intact.

Then, additional lens purchases for the MF system look like any given year.

Separately I agree unless there is a dramatically improvement in sensor QE, you'd have to increase sensor size for much better IQ. Larger sensor -> better IQ on the same QE of sensors, a simple law of physics.

Noise and DR aside, what about detail i.e. equal MPs, equal details or no?

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Rick Knepper
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Re: I believe it's a hard task for Canon to equal the MF.
In reply to Silverback1988, 8 months ago

Silverback1988 wrote:

Hi Rick,

Rick Knepper wrote:

FF > MF that is.

Yes this will concern a rumored Canon camera, not an actual one (at least for the moment).

It's still fun to speculate a rumored Camera.

I am pretty comfortable in my understanding that more MPs per given area results in more detail.

Yes, if the glass allowed I believe.

Let's say this rumored camera, casually referred to on this forum as the High Resolution Monster, has 51 MPs just like the Pentax 645Z.

Those same number of MPs will be laid out on .79x less area on Canon's FF sensor as opposed the Pentax sensor.

It will be a stretch for the FF glass to match the MF glass. I don't know the crop factor exactly,

I've heard this before but didn't really stop to think it out because until two weeks ago, I going anywhere beyond FF.

so I just take your number, 0.79 it is.

The FF glass need to be 1.26 x sharper at 0.79x f ratio from the MF lens to match exactly what MF system is producing.

ie. the MF is at 80mm f/4 ---> FF is at 64mm f/3.2 and the FF lens must be 1.26 times sharper than the MF lens at that setting.

If the Canon could do that, so it will be less point to go MF.

I hope Great Bustard will join in. He is good with numbers

and also good with hypothetical condition

I've contacted him privately about the thread. Hope he shows or maybe bobn2.

I have admitted in the past that I am fuzzy on cross platform equivalency but until now I have not been interested in anything but FF. The Pentax 645Z may change that.

I hope the Pentax will make other company lower their price

Or... I will start saving my money for the Pentax

Noise and DR aside, which set of 51 MPs will produce more detail, less detail or the same detail in the respective systems all other things being equal?

GB mentioned large pixel blur the other day so I am interested if that concept applies here in any way since the pixels on the Pentax sensor will be larger.

I think GB talk about the same format, the larger pixel means less MP.

Thus it doesn't apply here on the Pentax's 51 MP vs Canon 51 MP FF.

Anyone not familiar with the Pentax 645Z can catch up here:

http://www.dpreview.com/news/2014/04/15/hands-on-with-the-pentax-645z?utm_campaign=internal-link&utm_source=mainmenu&utm_medium=text&ref=mainmenu

The pros of the 645Z, $8499, 51 MPs. on a sensor larger than FF, weather sealed, 25 cross-type AF points, and wait for it.............. articulating LCD.

yes, articulating LCD !!

The cons: 3 fps.

Not a problem for me. Even 1 fps will make me happy, as long I got the discount in price

Lenses for the system mostly look reasonably priced although you won't find any pity-fifty pricing. The MF>FF crop factor is .79 according to DPR.

http://www.bhphotovideo.com/bnh/controller/home?O=&sku=1045517&gclid=CMOVld_K5L0CFdBcMgodCCkAGA&is=REG&Q=&A=details

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Rick Knepper, photographer, shooting for pleasure. It is better to have It and not need It than need It and not have It. Various RAW comparisons at Link below. Includes 5D3 vs D800E (new uploads), 5D3 vs. 6D, Zeiss lenses etc. https://app.box.com/s/71w40ita6hrcfghojaie

-

Brian

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Rick Knepper, photographer, shooting for pleasure. It is better to have It and not need It than need It and not have It. Various RAW comparisons at Link below. Includes 5D3 vs D800E (new uploads), 5D3 vs. 6D, Zeiss lenses etc. https://app.box.com/s/71w40ita6hrcfghojaie

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Rick Knepper
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Re: Cross platform equivalency
In reply to Keith Z Leonard, 8 months ago

Keith Z Leonard wrote:

If you have read any of the several thousand crop vs 35mm arguments over the years it's all the same stuff applied to MF vs 35mm. I have been pointing out for years that this is the case, that for some reason people have decided that 35mm is the "perfect" balance of price/performance, which really means they can afford 35mm. If money is not an object and there exists something better, well, you see where I'm going with this.

The issue has been that crop and 35mm really have been the sweet spot in terms of selling cameras to people, so they have enjoyed the most focus on tech advancement. With all of the talk about DSLR saturation you might start to see more MF cameras like the Pentax who target working pros who can afford then and are seeking something to differentiate themselves from the mom/dad with a camera crowd.

Anyway, to the crop stuff. 1.27 or so crop factor means that we are comparing a difference pretty close to the difference between 35mm and APS-H. If the sensors are of the same tech generation you will get better images from the 51mp MF sensor, all other things being equal. You will get thinner depth of field from the MF as well, which seems to be a key argument among the anti-crop movement.

Noise and DR aside, and given the same MPs, which sensor will produce more detail?

The real question comes down to whether or not you need it. The d800's 36mp is interesting, I personally don't need it for what I want to do. I usually don't need 20mp either, if I'm being honest. All of these arguments about getting the best hardware often makes a pretty insignificant difference to your average photo, it's more about the outlying images that make people go ooo and aaaa.

You know, this made me think of something I just read of Galen Rowell a couple days ago. I think it was advice in a magazine article given in a top ten list format. He said don't take record shots. Shoot every shot like its going into National Geographic. I'd probably want the best IQ for National Geographic.

Summation, the Pentax images SHOULD be better than a Canon 35mm with the same pixel count, due to larger surface area, all things being equal. Does that justify the cost difference that we'll likely see? Hard to say as the Canon camera doesn't exist. Are there other features of the Canon that make it a better fit for your uses?? Again, hard to say.

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Great Bustard
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My ears were burning. ; -)
In reply to Rick Knepper, 8 months ago

Rick Knepper wrote:

FF > MF that is.

Yes this will concern a rumored Canon camera, not an actual one (at least for the moment).

I am pretty comfortable in my understanding that more MPs per given area results in more detail.

Let's say this rumored camera, casually referred to on this forum as the High Resolution Monster, has 51 MPs just like the Pentax 645Z.

Those same number of MPs will be laid out on .79x less area on Canon's FF sensor as opposed the Pentax sensor.

I have admitted in the past that I am fuzzy on cross platform equivalency but until now I have not been interested in anything but FF. The Pentax 645Z may change that.

Noise and DR aside, which set of 51 MPs will produce more detail, less detail or the same detail in the respective systems all other things being equal?

GB mentioned large pixel blur the other day so I am interested if that concept applies here in any way since the pixels on the Pentax sensor will be larger.

Anyone not familiar with the Pentax 645Z can catch up here:

http://www.dpreview.com/news/2014/04/15/hands-on-with-the-pentax-645z?utm_campaign=internal-link&utm_source=mainmenu&utm_medium=text&ref=mainmenu

The pros of the 645Z, $8499, 51 MPs. on a sensor larger than FF, weather sealed, 25 cross-type AF points, and wait for it.............. articulating LCD.

The cons: 3 fps.

Lenses for the system mostly look reasonably priced although you won't find any pity-fifty pricing. The MF>FF crop factor is .79 according to DPR.

http://www.bhphotovideo.com/bnh/controller/home?O=&sku=1045517&gclid=CMOVld_K5L0CFdBcMgodCCkAGA&is=REG&Q=&A=details

Here we are:

http://www.josephjamesphotography.com/equivalence/#lensvssensor

In short, the resolution as a function of sensor size and pixel count can be summed up as follows:

For a given lens sharpness, the difference in resolution (lw/ph) between two systems will be between the ratio of the sensor heights (enlargement ratio) and the ratio of picture height in pixels (linear pixel density). The sharper the lens, the closer the balance will be to the ratio of linear pixel density, the less sharp the lens, the closer the balance will be to the enlargement ratio.

More specifically, the lenses for a 51 MP FF DSLR with the same AA filter as the 645Z will have to be 1.3x sharper than the lenses used on the 645Z to resolve as well.

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qianp2k
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Re: My ears were burning. ; -)
In reply to Great Bustard, 8 months ago

Great Bustard wrote:

Rick Knepper wrote:

FF > MF that is.

Yes this will concern a rumored Canon camera, not an actual one (at least for the moment).

I am pretty comfortable in my understanding that more MPs per given area results in more detail.

Let's say this rumored camera, casually referred to on this forum as the High Resolution Monster, has 51 MPs just like the Pentax 645Z.

Those same number of MPs will be laid out on .79x less area on Canon's FF sensor as opposed the Pentax sensor.

I have admitted in the past that I am fuzzy on cross platform equivalency but until now I have not been interested in anything but FF. The Pentax 645Z may change that.

Noise and DR aside, which set of 51 MPs will produce more detail, less detail or the same detail in the respective systems all other things being equal?

GB mentioned large pixel blur the other day so I am interested if that concept applies here in any way since the pixels on the Pentax sensor will be larger.

Anyone not familiar with the Pentax 645Z can catch up here:

http://www.dpreview.com/news/2014/04/15/hands-on-with-the-pentax-645z?utm_campaign=internal-link&utm_source=mainmenu&utm_medium=text&ref=mainmenu

The pros of the 645Z, $8499, 51 MPs. on a sensor larger than FF, weather sealed, 25 cross-type AF points, and wait for it.............. articulating LCD.

The cons: 3 fps.

Lenses for the system mostly look reasonably priced although you won't find any pity-fifty pricing. The MF>FF crop factor is .79 according to DPR.

http://www.bhphotovideo.com/bnh/controller/home?O=&sku=1045517&gclid=CMOVld_K5L0CFdBcMgodCCkAGA&is=REG&Q=&A=details

Here we are:

http://www.josephjamesphotography.com/equivalence/#lensvssensor

In short, the resolution as a function of sensor size and pixel count can be summed up as follows:

For a given lens sharpness, the difference in resolution (lw/ph) between two systems will be between the ratio of the sensor heights (enlargement ratio) and the ratio of picture height in pixels (linear pixel density). The sharper the lens, the closer the balance will be to the ratio of linear pixel density, the less sharp the lens, the closer the balance will be to the enlargement ratio.

More specifically, the lenses for a 51 MP FF DSLR with the same AA filter as the 645Z will have to be 1.3x sharper than the lenses used on the 645Z to resolve as well.

What your guys' opinions on IQ in 645Z samples?  Much better than D800E with Otus 55/1.4 or A7R with FE 55 at their respective full sizes?

http://www.sonyalpharumors.com/first-full-size-image-samples-wiht-the-sony-50mp-mf-sensor-of-the-pentax/

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In reply to Great Bustard, 8 months ago

Great Bustard wrote:

Rick Knepper wrote:

FF > MF that is.

Yes this will concern a rumored Canon camera, not an actual one (at least for the moment).

I am pretty comfortable in my understanding that more MPs per given area results in more detail.

Let's say this rumored camera, casually referred to on this forum as the High Resolution Monster, has 51 MPs just like the Pentax 645Z.

Those same number of MPs will be laid out on .79x less area on Canon's FF sensor as opposed the Pentax sensor.

I have admitted in the past that I am fuzzy on cross platform equivalency but until now I have not been interested in anything but FF. The Pentax 645Z may change that.

Noise and DR aside, which set of 51 MPs will produce more detail, less detail or the same detail in the respective systems all other things being equal?

GB mentioned large pixel blur the other day so I am interested if that concept applies here in any way since the pixels on the Pentax sensor will be larger.

Anyone not familiar with the Pentax 645Z can catch up here:

http://www.dpreview.com/news/2014/04/15/hands-on-with-the-pentax-645z?utm_campaign=internal-link&utm_source=mainmenu&utm_medium=text&ref=mainmenu

The pros of the 645Z, $8499, 51 MPs. on a sensor larger than FF, weather sealed, 25 cross-type AF points, and wait for it.............. articulating LCD.

The cons: 3 fps.

Lenses for the system mostly look reasonably priced although you won't find any pity-fifty pricing. The MF>FF crop factor is .79 according to DPR.

http://www.bhphotovideo.com/bnh/controller/home?O=&sku=1045517&gclid=CMOVld_K5L0CFdBcMgodCCkAGA&is=REG&Q=&A=details

Here we are:

http://www.josephjamesphotography.com/equivalence/#lensvssensor

In short, the resolution as a function of sensor size and pixel count can be summed up as follows:

For a given lens sharpness, the difference in resolution (lw/ph) between two systems will be between the ratio of the sensor heights (enlargement ratio) and the ratio of picture height in pixels (linear pixel density). The sharper the lens, the closer the balance will be to the ratio of linear pixel density, the less sharp the lens, the closer the balance will be to the enlargement ratio.

More specifically, the lenses for a 51 MP FF DSLR with the same AA filter as the 645Z will have to be 1.3x sharper than the lenses used on the 645Z to resolve as well.

I'll draw from a statement you made in another thread: even dull lenses will produce more detail when combined with a higher resolution sensor vs. a lower resolution sensor [both sensors having the same area].

You also mentioned (probably off hand) something about large pixel blur.

Sorry to be dense, but assuming all lenses are equivalent (FF = 1.3x sharper than MF), and noise and DR aside, will the two systems capture equal detail? Conversely, if the lenses from both systems are equal in sharpness (not equivalent), will the larger sensor produce more detail?

To determine the equivalency of FF vs. MF lenses, does one compare MTF charts and do you have to use a multiplier (1.3z) to determine relative sharpness.

Or does anyone know off the top of their head? Are Canon lenses 1.3x sharper?

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Re: My ears were burning. ; -)
In reply to qianp2k, 8 months ago

qianp2k wrote:

Great Bustard wrote:

Rick Knepper wrote:

FF > MF that is.

Yes this will concern a rumored Canon camera, not an actual one (at least for the moment).

I am pretty comfortable in my understanding that more MPs per given area results in more detail.

Let's say this rumored camera, casually referred to on this forum as the High Resolution Monster, has 51 MPs just like the Pentax 645Z.

Those same number of MPs will be laid out on .79x less area on Canon's FF sensor as opposed the Pentax sensor.

I have admitted in the past that I am fuzzy on cross platform equivalency but until now I have not been interested in anything but FF. The Pentax 645Z may change that.

Noise and DR aside, which set of 51 MPs will produce more detail, less detail or the same detail in the respective systems all other things being equal?

GB mentioned large pixel blur the other day so I am interested if that concept applies here in any way since the pixels on the Pentax sensor will be larger.

Anyone not familiar with the Pentax 645Z can catch up here:

http://www.dpreview.com/news/2014/04/15/hands-on-with-the-pentax-645z?utm_campaign=internal-link&utm_source=mainmenu&utm_medium=text&ref=mainmenu

The pros of the 645Z, $8499, 51 MPs. on a sensor larger than FF, weather sealed, 25 cross-type AF points, and wait for it.............. articulating LCD.

The cons: 3 fps.

Lenses for the system mostly look reasonably priced although you won't find any pity-fifty pricing. The MF>FF crop factor is .79 according to DPR.

http://www.bhphotovideo.com/bnh/controller/home?O=&sku=1045517&gclid=CMOVld_K5L0CFdBcMgodCCkAGA&is=REG&Q=&A=details

Here we are:

http://www.josephjamesphotography.com/equivalence/#lensvssensor

In short, the resolution as a function of sensor size and pixel count can be summed up as follows:

For a given lens sharpness, the difference in resolution (lw/ph) between two systems will be between the ratio of the sensor heights (enlargement ratio) and the ratio of picture height in pixels (linear pixel density). The sharper the lens, the closer the balance will be to the ratio of linear pixel density, the less sharp the lens, the closer the balance will be to the enlargement ratio.

More specifically, the lenses for a 51 MP FF DSLR with the same AA filter as the 645Z will have to be 1.3x sharper than the lenses used on the 645Z to resolve as well.

What your guys' opinions on IQ in 645Z samples? Much better than D800E with Otus 55/1.4 or A7R with FE 55 at their respective full sizes?

http://www.sonyalpharumors.com/first-full-size-image-samples-wiht-the-sony-50mp-mf-sensor-of-the-pentax/

Dang. I won't venture a guess on a comparison to a D800E or A7r with these two lenses, but the images at the link have more clarity at 16% mag than I have been able to wring from my D800 and lenses and my PPing. These have a realism I don't normally see from 35mm. To me, the second tree image has more of a 35mm look to it (or rather a look I am more familiar with) because it doesn't look as photo-realistic. I see some haloing in the image as well. The others are very nice.

I suppose it would help to know the lenses that are part of the capture.

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Just another Canon shooter
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Re: My ears were burning. ; -)
In reply to Rick Knepper, 8 months ago

Rick Knepper wrote:

Sorry to be dense, but assuming all lenses are equivalent (FF = 1.3x sharper than MF), and noise and DR aside, will the two systems capture equal detail?

Yes.

Conversely, if the lenses from both systems are equal in sharpness (not equivalent), will the larger sensor produce more detail?

Yes.

But ... lenses for larger sensors are not equivalent in sharpness for whatever reason, at equivalent settings. The typical performance is somewhere between the two cases above; and larger systems resolve more (try posting this in the m43 forum).

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Re: Cross platform equivalency
In reply to Rick Knepper, 8 months ago

Rick Knepper wrote:

Anyway, to the crop stuff. 1.27 or so crop factor means that we are comparing a difference pretty close to the difference between 35mm and APS-H. If the sensors are of the same tech generation you will get better images from the 51mp MF sensor, all other things being equal. You will get thinner depth of field from the MF as well, which seems to be a key argument among the anti-crop movement.

Noise and DR aside, and given the same MPs, which sensor will produce more detail?

I would think the larger sensor will have greater resolution much the same way that a 35mm sensor does vs aps-c.

The real question comes down to whether or not you need it. The d800's 36mp is interesting, I personally don't need it for what I want to do. I usually don't need 20mp either, if I'm being honest. All of these arguments about getting the best hardware often makes a pretty insignificant difference to your average photo, it's more about the outlying images that make people go ooo and aaaa.

You know, this made me think of something I just read of Galen Rowell a couple days ago. I think it was advice in a magazine article given in a top ten list format. He said don't take record shots. Shoot every shot like its going into National Geographic. I'd probably want the best IQ for National Geographic.

Fair point!

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Re: My ears were burning. ; -)
In reply to Just another Canon shooter, 8 months ago

Just another Canon shooter wrote:

But ... lenses for larger sensors are not equivalent in sharpness for whatever reason, at equivalent settings. The typical performance is somewhere between the two cases above; and larger systems resolve more (try posting this in the m43 forum).

This is what I figured hence my question regarding MTFs of the various lenses in question.

I guess I am suddenly finding myself in the same situation crop shooters have been in since the release of the 5D and which I have scoffed at for as many years: trying to figure out which system is better sight unseen. In this case though, I am betting that B&H and Adorama will NOT have the same type of return policy for a 645Z that they do for Canon and Nikon 35mm gear.

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Re: Cross platform equivalency
In reply to Keith Z Leonard, 8 months ago

Keith Z Leonard wrote:

If you have read any of the several thousand crop vs 35mm arguments over the years it's all the same stuff applied to MF vs 35mm. I have been pointing out for years that this is the case, that for some reason people have decided that 35mm is the "perfect" balance of price/performance, which really means they can afford 35mm. If money is not an object and there exists something better, well, you see where I'm going with this.

The issue has been that crop and 35mm really have been the sweet spot in terms of selling cameras to people, so they have enjoyed the most focus on tech advancement. With all of the talk about DSLR saturation you might start to see more MF cameras like the Pentax who target working pros who can afford then and are seeking something to differentiate themselves from the mom/dad with a camera crowd.

Anyway, to the crop stuff. 1.27 or so crop factor means that we are comparing a difference pretty close to the difference between 35mm and APS-H. If the sensors are of the same tech generation you will get better images from the 51mp MF sensor, all other things being equal. You will get thinner depth of field from the MF as well, which seems to be a key argument among the anti-crop movement.

One thing I don’t see with pentax is fast glass, the fastest I could find in production is F2.8 so this would be like F2.2 on FF

My question, can a FF 1.4 lens stopped down to F2.2 be as sharp as a 645crop F2.8 shot wide open?

would this not give an edge to FF ?

If the cropped 645z was a true 645 I could see the advantage of the F2.8, but not having anything faster for the cropped 645 really   equals out the playing field in noise and resolution would it not ?

The real question comes down to whether or not you need it. The d800's 36mp is interesting, I personally don't need it for what I want to do. I usually don't need 20mp either, if I'm being honest. All of these arguments about getting the best hardware often makes a pretty insignificant difference to your average photo, it's more about the outlying images that make people go ooo and aaaa.

Summation, the Pentax images SHOULD be better than a Canon 35mm with the same pixel count, due to larger surface area, all things being equal. Does that justify the cost difference that we'll likely see? Hard to say as the Canon camera doesn't exist. Are there other features of the Canon that make it a better fit for your uses?? Again, hard to say.

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Re: Cross platform equivalency
In reply to qianp2k, 8 months ago

qianp2k wrote:

Keith Z Leonard wrote:

If you have read any of the several thousand crop vs 35mm arguments over the years it's all the same stuff applied to MF vs 35mm. I have been pointing out for years that this is the case, that for some reason people have decided that 35mm is the "perfect" balance of price/performance, which really means they can afford 35mm. If money is not an object and there exists something better, well, you see where I'm going with this.

Yes similar comparison but in higher diminishing return. 645Z is 0.78x crop that makes 35mm FF sensor roughly 1.3x crop to this MF sensor (which itself a crop MF sensor compared to bigger CCD MF sensor in PhaseOne IQ280 and Mamiya 645DF).

This is a fair point.

According to DPR, the Mamiya/Phase One 645DF+ body alone was $6,000 at release. The back: $42,000 on eBay. FF 645 (6 cm x 4.5 cm = 60mm x 45mm) vs. the Pentax crop (43.8 x 32.8 mm).

You only see noticeable difference when you print/view in very big size. Bear mind mind that it seems true Sony 54mp sensor and a high pixel Canon sensor are coming.

For detail, someone coming from 22 MP may be more wowed than someone coming from 36 MP.

The issue has been that crop and 35mm really have been the sweet spot in terms of selling cameras to people, so they have enjoyed the most focus on tech advancement. With all of the talk about DSLR saturation you might start to see more MF cameras like the Pentax who target working pros who can afford then and are seeking something to differentiate themselves from the mom/dad with a camera crowd.

That's the point that FF cameras are sweet spot, mature enough with most features, and affordable enough in these days, more and most versatile lens choice. Also much lighter and smaller and lots cheaper. Nevertheless this 645Z makes a MF relative affordable to some Pros and enthusiasts who pursuing the best IQ on still relative affordable price.

Anyway, to the crop stuff. 1.27 or so crop factor means that we are comparing a difference pretty close to the difference between 35mm and APS-H. If the sensors are of the same tech generation you will get better images from the 51mp MF sensor, all other things being equal. You will get thinner depth of field from the MF as well, which seems to be a key argument among the anti-crop movement.

As said in higher diminishing return. DOF is not really an issue on equivalent DOF. FF f2.8 is eq to 645Z's f3.5.

Since you posted those samples below, what say you now regarding diminishing return?

The real question comes down to whether or not you need it. The d800's 36mp is interesting, I personally don't need it for what I want to do. I usually don't need 20mp either, if I'm being honest. All of these arguments about getting the best hardware often makes a pretty insignificant difference to your average photo, it's more about the outlying images that make people go ooo and aaaa.

Someone needs it but I am sure less need 645 than FF especially when Sony and Canon if released 50mp FF cameras in later this year. Not sure how good of DR in this 51mp Sony MF sensor, still 14-stop or 16-stop?

Summation, the Pentax images SHOULD be better than a Canon 35mm with the same pixel count, due to larger surface area, all things being equal. Does that justify the cost difference that we'll likely see? Hard to say as the Canon camera doesn't exist. Are there other features of the Canon that make it a better fit for your uses?? Again, hard to say.

More meaningful if this 51mp MF sensor compares to forthcoming 54mp FF sensor from Sony (if the rumor is true that at least as good as current 36mp sensor in other aspects) or on Canon 40+ mp sensor (we have no idea how good of Canon sensor). I suspect unless you use best of best MF prime lenses and print/view in extreme big size, the difference is not that big. I have no ideas of MF lenses (except they are very expensive), are some of them as good as Otus 55/1.4, FE 55/1.8, Sigma 50/1.4 A and Sigma 35/1.4 A respectively?

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Re: My ears were burning. ; -)
In reply to qianp2k, 8 months ago

qianp2k wrote:

Great Bustard wrote:

Rick Knepper wrote:

FF > MF that is.

Yes this will concern a rumored Canon camera, not an actual one (at least for the moment).

I am pretty comfortable in my understanding that more MPs per given area results in more detail.

Let's say this rumored camera, casually referred to on this forum as the High Resolution Monster, has 51 MPs just like the Pentax 645Z.

Those same number of MPs will be laid out on .79x less area on Canon's FF sensor as opposed the Pentax sensor.

I have admitted in the past that I am fuzzy on cross platform equivalency but until now I have not been interested in anything but FF. The Pentax 645Z may change that.

Noise and DR aside, which set of 51 MPs will produce more detail, less detail or the same detail in the respective systems all other things being equal?

GB mentioned large pixel blur the other day so I am interested if that concept applies here in any way since the pixels on the Pentax sensor will be larger.

Anyone not familiar with the Pentax 645Z can catch up here:

http://www.dpreview.com/news/2014/04/15/hands-on-with-the-pentax-645z?utm_campaign=internal-link&utm_source=mainmenu&utm_medium=text&ref=mainmenu

The pros of the 645Z, $8499, 51 MPs. on a sensor larger than FF, weather sealed, 25 cross-type AF points, and wait for it.............. articulating LCD.

The cons: 3 fps.

Lenses for the system mostly look reasonably priced although you won't find any pity-fifty pricing. The MF>FF crop factor is .79 according to DPR.

http://www.bhphotovideo.com/bnh/controller/home?O=&sku=1045517&gclid=CMOVld_K5L0CFdBcMgodCCkAGA&is=REG&Q=&A=details

Here we are:

http://www.josephjamesphotography.com/equivalence/#lensvssensor

In short, the resolution as a function of sensor size and pixel count can be summed up as follows:

For a given lens sharpness, the difference in resolution (lw/ph) between two systems will be between the ratio of the sensor heights (enlargement ratio) and the ratio of picture height in pixels (linear pixel density). The sharper the lens, the closer the balance will be to the ratio of linear pixel density, the less sharp the lens, the closer the balance will be to the enlargement ratio.

More specifically, the lenses for a 51 MP FF DSLR with the same AA filter as the 645Z will have to be 1.3x sharper than the lenses used on the 645Z to resolve as well.

What your guys' opinions on IQ in 645Z samples? Much better than D800E with Otus 55/1.4 or A7R with FE 55 at their respective full sizes?

http://www.sonyalpharumors.com/first-full-size-image-samples-wiht-the-sony-50mp-mf-sensor-of-the-pentax/

They're all right, I suppose.  I mean, cell phones have 41 MP nowadays, so...

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Re: My ears were burning. ; -)
In reply to Rick Knepper, 8 months ago

Rick Knepper wrote:

Great Bustard wrote:

Rick Knepper wrote:

FF > MF that is.

Yes this will concern a rumored Canon camera, not an actual one (at least for the moment).

I am pretty comfortable in my understanding that more MPs per given area results in more detail.

Let's say this rumored camera, casually referred to on this forum as the High Resolution Monster, has 51 MPs just like the Pentax 645Z.

Those same number of MPs will be laid out on .79x less area on Canon's FF sensor as opposed the Pentax sensor.

I have admitted in the past that I am fuzzy on cross platform equivalency but until now I have not been interested in anything but FF. The Pentax 645Z may change that.

Noise and DR aside, which set of 51 MPs will produce more detail, less detail or the same detail in the respective systems all other things being equal?

GB mentioned large pixel blur the other day so I am interested if that concept applies here in any way since the pixels on the Pentax sensor will be larger.

Anyone not familiar with the Pentax 645Z can catch up here:

http://www.dpreview.com/news/2014/04/15/hands-on-with-the-pentax-645z?utm_campaign=internal-link&utm_source=mainmenu&utm_medium=text&ref=mainmenu

The pros of the 645Z, $8499, 51 MPs. on a sensor larger than FF, weather sealed, 25 cross-type AF points, and wait for it.............. articulating LCD.

The cons: 3 fps.

Lenses for the system mostly look reasonably priced although you won't find any pity-fifty pricing. The MF>FF crop factor is .79 according to DPR.

http://www.bhphotovideo.com/bnh/controller/home?O=&sku=1045517&gclid=CMOVld_K5L0CFdBcMgodCCkAGA&is=REG&Q=&A=details

Here we are:

http://www.josephjamesphotography.com/equivalence/#lensvssensor

In short, the resolution as a function of sensor size and pixel count can be summed up as follows:

For a given lens sharpness, the difference in resolution (lw/ph) between two systems will be between the ratio of the sensor heights (enlargement ratio) and the ratio of picture height in pixels (linear pixel density). The sharper the lens, the closer the balance will be to the ratio of linear pixel density, the less sharp the lens, the closer the balance will be to the enlargement ratio.

More specifically, the lenses for a 51 MP FF DSLR with the same AA filter as the 645Z will have to be 1.3x sharper than the lenses used on the 645Z to resolve as well.

I'll draw from a statement you made in another thread: even dull lenses will produce more detail when combined with a higher resolution sensor vs. a lower resolution sensor [both sensors having the same area].

Correct. However, the sharper the lens, the greater the benefit. For example, a mediocre lens might show a 15% increase in resolution going from 22 MP to 51 MP whereas a sharp lens might show a 35% increase in resolution (the max possible increase is sqrt 51/22 = 1.52 = 52% increase, which presumes a very sharp lens, indeed, negligible motion blur and negligible diffraction).

You also mentioned (probably off hand) something about large pixel blur.

Pixel size is one form of blur. The more pixels you have, the less blur you have. However, that doesn't mean that larger pixels on a larger sensor are not more blurry than smaller pixels on a smaller sensor.

Sorry to be dense, but assuming all lenses are equivalent (FF = 1.3x sharper than MF), and noise and DR aside, will the two systems capture equal detail?

Yes. Except, we can't cast noise entirely aside as noise does affect resolution. However, in this case, for equally efficient sensors, I don't see that as contributing anything but a minor, if not entirely insignificant, difference.

Conversely, if the lenses from both systems are equal in sharpness (not equivalent), will the larger sensor produce more detail?

Yes.

To determine the equivalency of FF vs. MF lenses, does one compare MTF charts and do you have to use a multiplier (1.3z) to determine relative sharpness.

Yes. For example, if using the manufacturer MTFs, you would compare 10 lp/mm and 30 lp/mm on FF to 7.7 lp/mm and 23 lp/mm on 0.77x. You don't just multiply or divide measured or calculated MTFs by 1.3, by the way -- you have to measure resolution at the equivalent lp/mm.

Or does anyone know off the top of their head? Are Canon lenses 1.3x sharper?

I don't know anything about the sharpness of medium format lenses. I imagine one would have to take it on a lens by lens basis. Consider, for example, how different the 24-70 / 2.8L and 24-70 / 2.8L II are.

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