FF Commentary by Thom

Started Nov 4, 2013 | Discussions
Adrian Van Contributing Member • Posts: 684
Re: FX to DX sensors and differences in prints or on screen.....
1

Here is something to remember: If you were printing a 2"by 3" photo, could you tell the difference between FF and crop sensor? Not likely.

Depends on the ISO of the image capture, the pro glass used, and raw editing software used.

If ISO was say 100 to 800 with pro glass and Lightroom for example for noise reduction, possibly not much difference, but I could tell as there could be some still.

If the image was taken in very low light at 3200 iso or more, even with pro glass, there would still be a noticeable difference (even to anything over 1600 iso will show) to the fine detail sharpness or crispness of the image as better with FX sensor.

I have looked at 100 percent images from D7100 at pixel level, and my own 4 year old D700 FX with 24-70mm lens is miles ahead in low noise over DX, (maybe not full pixel resolution). However, even at 12MP in D700, not 24mp in D7100, with editing software because of the crisp image, I can pull out lots of detail information in the Raw file from the FX image and do so regularly in 16x20 prints. D700 images look great printed large. D800 would no doubt be better.

DXO mark of D7100 is about 1265 iso for light vs 2300 iso for low light on D700 FX (nearly double for better low light, and the D800 at around 2800iso for low light on DXOmark. These differences show up in prints.

Will be noticeable in large prints if image is a low light capture photo at 1600 to 3200iso, due to the crispness of the image capture. Even at 400 to 800 iso, there could be difference in very large prints.

Pro glass can improve the difference between the two, along with noise reduction in Raw software, along with distance to subject, I have found with my FX and DX cameras.

When I saw the samples of the D7100 online, I was surprised how much better my D700 images still were for a four year old camera. If you have used FX and DX, you will know this already.

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KL Matt Veteran Member • Posts: 5,885
Re: FF Commentary by Thom

sportyaccordy wrote:
A bunch of $3000 cameras that have a lot of overlap is a good thing.

I'm sorry, but I totally disagree with your statement here, sportyaccordy. Why would you say something like this?

KL MATT

janneman02 Forum Pro • Posts: 15,733
Re: Good points hardly anybods needs
1

KL Matt wrote:

Janneman winks can get you into trouble. The last time I traded winks with a man and it was interpreted the wrong way. In the end I had to decline an offer, and he was offended!

Not winking back,

Matt

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sportyaccordy Forum Pro • Posts: 12,308
Re: FF Commentary by Thom
1

John_A_G wrote:

sportyaccordy wrote:

He is trolling for website hits. Many of his criticisms don't even make sense, and I'm pretty sure he knows this.

of course he is. He writes a blog. His goal is to get people to read his blog and he needs to be controversial in order to do that.

I'm fine with that; but if we are in agreement on that then folks need to stop citing his opinions as legitimate/respectable. Literally every time I have seen one of his posts this year they have been riddled with strawmen and contradictions designed to do nothing but inflame the reader.

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moving_comfort
moving_comfort Veteran Member • Posts: 8,231
They got it
1

KL Matt wrote:

sportyaccordy wrote:

KL Matt wrote:

Ontario Gone wrote:

KL Matt wrote:

Other than a better lens selection, broader dynamic range, greater color depth, higher resolution, and greater control over depth of field, there is absolutely no reason to purchase a full frame camera in this day and age. I have no idea what all the fuss is about.

^I am KL MATT and I DO NOT approve of this message!!!!

^The winking smiley means I'M NOT SERIOUS ABOUT THE ABOVE! And, it's what Thom Hogan said, NOT ME!!! AAAARRRTTGADGGDSADFfdjsalkjzx.,

Matt

What is interesting is when we start asking different questions, like, why stop at FF? If bigger means better, why not go for MF? That question kind of takes the wind out of the whole argument, bc it shows the question isn't about "better" it's about standards vs price. Everybody has a "good enough" level of expectation, and for some, apsc is good enough. For others, MF is the smallest they will accept.

Pentax is busy making cameras for people who think apsc is good enough for their needs, and at the right price. And I refute your better lens selection point,

OMG OMG OMG I'm gonna freak out right here on the Internet!

WHOSE better lens selection "point"? You can't POSSIBLY be referring to me, KL Matt, could you? Because it is NOT MY POINT! IT'S THOM HOGAN'S STUPID AND MOSTLY WRONG POINT!

Sorry to yell but a significant portion of this forum appears to be irony-deaf. I thought it might aid comprehension.

Matt

If you were looking to dump on FF you did a pretty poor job of doing so. Aside from color depth and DR I am pretty sure everything you listed IS a legitimate advantage of FF.

*&(*#% &)*()@)*( &&@++_)!@+_!

CAN YOU PEOPLE EVEN READ AT ALL????? AND IF NOT, HOW ARE YOU ABLE TO CLICK ON THE REPLY BUTTON AND TYPE SOMETHING????? DO YOU HAVE SOMEONE HELPING YOU DO THIS???

*(#*&#&$*

Matt, I think the problem is janneman and Ontario understood what you originally meant  with the sarcasm, and were making a counterpoint to that - in other words, they were obliquely supporting Hogan's view.

sportyaccordy sees that they understood your sarcasm, and then sees that you seem to be disavowing it now, which suggests that you really do not agree that those positive FF attributes after all - thus he addresses that.

In the end, you made a good, succinct, funny post originally...  and then misunderstood some reactions to it.  Mystery solved, you're welcome

.

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KL Matt Veteran Member • Posts: 5,885
Re: They got it

moving_comfort wrote:

KL Matt wrote:

sportyaccordy wrote:

KL Matt wrote:

Ontario Gone wrote:

KL Matt wrote:

Other than a better lens selection, broader dynamic range, greater color depth, higher resolution, and greater control over depth of field, there is absolutely no reason to purchase a full frame camera in this day and age. I have no idea what all the fuss is about.

^I am KL MATT and I DO NOT approve of this message!!!!

^The winking smiley means I'M NOT SERIOUS ABOUT THE ABOVE! And, it's what Thom Hogan said, NOT ME!!! AAAARRRTTGADGGDSADFfdjsalkjzx.,

Matt

What is interesting is when we start asking different questions, like, why stop at FF? If bigger means better, why not go for MF? That question kind of takes the wind out of the whole argument, bc it shows the question isn't about "better" it's about standards vs price. Everybody has a "good enough" level of expectation, and for some, apsc is good enough. For others, MF is the smallest they will accept.

Pentax is busy making cameras for people who think apsc is good enough for their needs, and at the right price. And I refute your better lens selection point,

OMG OMG OMG I'm gonna freak out right here on the Internet!

WHOSE better lens selection "point"? You can't POSSIBLY be referring to me, KL Matt, could you? Because it is NOT MY POINT! IT'S THOM HOGAN'S STUPID AND MOSTLY WRONG POINT!

Sorry to yell but a significant portion of this forum appears to be irony-deaf. I thought it might aid comprehension.

Matt

If you were looking to dump on FF you did a pretty poor job of doing so. Aside from color depth and DR I am pretty sure everything you listed IS a legitimate advantage of FF.

*&(*#% &)*()@)*( &&@++_)!@+_!

CAN YOU PEOPLE EVEN READ AT ALL????? AND IF NOT, HOW ARE YOU ABLE TO CLICK ON THE REPLY BUTTON AND TYPE SOMETHING????? DO YOU HAVE SOMEONE HELPING YOU DO THIS???

*(#*&#&$*

Matt, I think the problem is janneman and Ontario understood what you originally meant

And that was?

with the sarcasm, and were making a counterpoint to that

a counterpoint to *what*?

- in other words, they were obliquely supporting Hogan's view.

They can do that all day long. Has nothing to do with anything I think or say on my own behalf. My parody of Hogan was just that, a parody. Nothing more, nothing less. NOT a sneaky way of expressing my own personal opinion, which I have not yet done here. IT WAS JUST A JOKE.

sportyaccordy sees that they understood your sarcasm, and then sees that you seem to be disavowing it now, which suggests that you really do not agree that those positive FF attributes after all - thus he addresses that.

OMG what the ???? Is there anyone out there on the entire internet who can follow what he just said?

OK, alright, for the record here is what I think: Hogan is actually spot on for a lot of the details of his diatribe. Full Frame *is* better, all other things (lenses) remaining equal, in most of the ways he mentioned perhaps minus available lens selection. What destroys his credibility and makes him look a silly tweaker is that he spends considerable effort building up arguments that contradict his conclusion. Strangest darnn thing I've ever seen. What it boils down to is Hogan is saying to the average hobby photog: "you're not worthy, you don't need full frame, you're not good enough at photography for it to make one spit of difference, you peons you, *and* you can't afford it anyway, so get over yourselves and stop your disgusting drooling. FF is reserved for *real* photographers such as the likes of MYSELF." In the face of such arrogance, who can even concentrate on the arguments at hand????

Matt

Mark Ransom
Mark Ransom Veteran Member • Posts: 5,189
Re: FF Commentary by Thom

Roland Karlsson wrote:

It is not the F-number that determines how fast a lens is, it is the aperture diameter.

Therefore, an F8 lens might be faster than an F2 lens, if the F8 lens camera is more than 4x bigger.

Not sure I understand. Doesn't "faster" in this context mean you can use a faster shutter speed for the same light level and exposure? That's independent of sensor size.

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wolfd Senior Member • Posts: 1,262
Re: FF Commentary by Thom

Interesting opinion for sure. Thanks for sharing.

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Robert A F
OP Robert A F Senior Member • Posts: 1,297
Re: FF Commentary by Thom

Thom and I think everyone should own a Q, Nikon 1, Micro FourThirds, K-5, K-5IIs,  K-3, D7000, D7100, D300s, D700, D610, D800, D800E, all the lenses for each camera and just be happy. Sorry Canon users, I don't pay any attention to your products. Meamwhile you just missed the shot of the century because you couldn't decide which camera to take with you today.

Ontario Gone
Ontario Gone Veteran Member • Posts: 4,183
Re: FF Commentary by Thom
1

Mark Ransom wrote:

Roland Karlsson wrote:

It is not the F-number that determines how fast a lens is, it is the aperture diameter.

Therefore, an F8 lens might be faster than an F2 lens, if the F8 lens camera is more than 4x bigger.

Not sure I understand. Doesn't "faster" in this context mean you can use a faster shutter speed for the same light level and exposure? That's independent of sensor size.

Yea the above isnt true. The whole point of the F stop equation is to normalize the numbers so every lens is given a rating we understand. Diameter changes based on FL for a given F stop, yet SS would not. This means the amount of light doesnt change either.

For anybody who doesnt know, F2 on a 50mm lens means the choke diameter is 25mm (50/2). F2 on a 20mm lens would be 10mm. Both, at F2, allow the same light to hit the sensor, even though diameter is different.  So no, aperture diameter is useless unless we multiply it by FL, which is exactly what F stop does. Incidently this is why fast tele is so dang spendy.

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Bmoon Regular Member • Posts: 291
Re: FF Commentary by Thom

Mark Ransom wrote:

Roland Karlsson wrote:

It is not the F-number that determines how fast a lens is, it is the aperture diameter.

Therefore, an F8 lens might be faster than an F2 lens, if the F8 lens camera is more than 4x bigger.

Not sure I understand. Doesn't "faster" in this context mean you can use a faster shutter speed for the same light level and exposure? That's independent of sensor size.

Lets put it into context, looking at the new fast 1.8 zoom from sigma it shares the same aperture dia as its big brother 24-70 2.8 on a ff. Using that 1.8 on a dx camera would allow more total light to hit the sensor allowing you to use a faster shutter speed that a 2.8 lens on the same dx camera because you have increased the Ap dia. We know that 1.8 dx lens allows that same total light to fall on that dx sensor as the big brother 2.8 lens on FF so this would mean that the same shutter speed could be used on the dx at F1.8 as the FF at F2.8 and they would capture the same total light and would allow for the same shutter speed. The F stop is only regulates the light intensity striking the sensor and its the Ap dia that determines the total amount of light striking the sensor and is really that what determines the shutter speed. Many will argue that they can shoot DX at iso 100 F2.8 1/100sec and on ff iso100 2.8 1/100sec so that 2.8 lens n dx is as fast as the FF lens but they fail to see that the FF image captured 2.25 times more light so that image would contain lmore than half the noise so to equalize the total light striking the sensor one could shoot that FF at iso 225 and increase the shutter speed by 1 stop and still capture the same noise ( total light) as its DX brother but at a faster shutter speed. F stop is really meaningless when comparing between formats as it only gauges the light intensity striking the sensor with 2 vastly different sensors dimensions.

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Ontario Gone
Ontario Gone Veteran Member • Posts: 4,183
Re: FF Commentary by Thom

You are ignoring the fact that a FF sensor is bigger and NEEDS more light to produce a given intensity photo (exposure). A FF lens has a wider light path bc of this, but the light itself is not "more intense", for that you use a speed booster with an oversized lens on undersized sensor.

Comparing a FF 50mm @F2 and a crop 50mm @F2, yes the FF lens allows more light total, but for any given sensor size the exposure is identical. This is bc the intensity of the two light paths are equal, one is just wider. Speed boosters condense the path, increasing the intensity and thats why the F stop changes too.

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Bmoon Regular Member • Posts: 291
Re: FF Commentary by Thom

Ontario Gone wrote:

You are ignoring the fact that a FF sensor is bigger and NEEDS more light to produce a given intensity photo (exposure). A FF lens has a wider light path bc of this, but the light itself is not "more intense", for that you use a speed booster with an oversized lens on undersized sensor.

EV determines the light intensity striking the sensor a photo taken with a F2.0 at 1/100sec has the same EV as a FF F2 1/100 so per unit of surface is the same but the size difference in the sensor allows for 2.25 time more light gathered (Total Light)

Comparing a FF 50mm @F2 and a crop 50mm @F2, yes the FF lens allows more light total, but for any given sensor size the exposure is identical. This is bc the intensity of the two light paths are equal, one is just wider. Speed boosters condense the path, increasing the intensity and thats why the F stop changes too.

Using a speed booster just show you how much more light is gathered using FF because you have just focused all that light onto that smaller sensor

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paulkienitz
paulkienitz Veteran Member • Posts: 5,295
Re: My Summary

On the one hand I’m getting the feeling that I have spoken too soon, without fully getting the science right. But I have photos which are say 7 images stitched together, that look reasonably normal for a curved scene transferred to a flat surface. To achieve the same view with a single lens I would have needed a fish eye and that would not look the same at all. There must be some other element to this argument which I have not explained well in previous posts. Do you know of a website which puts this all into prospective?

What's probably happening is that your stitching program is combining the images into something that's more a cylindrical projection than a planar one.

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Ontario Gone
Ontario Gone Veteran Member • Posts: 4,183
Re: FF Commentary by Thom

Bmoon wrote:

The F stop is only regulates the light intensity striking the sensor and its the Ap dia that determines the total amount of light striking the sensor and is really that what determines the shutter speed.

Let me back up here. What exactly do you mean by regulate? Everything I have ever read and heard suggests F stop is simply a way to gauge the exposure of a sensor. The lens determines how much light is let through, but the sensor size is what determines how much of that light gets absorbed. Does the entire industry have it wrong?

Many will argue that they can shoot DX at iso 100 F2.8 1/100sec and on ff iso100 2.8 1/100sec so that 2.8 lens n dx is as fast as the FF lens but they fail to see that the FF image captured 2.25 times more light so that image would contain lmore than half the noise so to equalize the total light striking the sensor one could shoot that FF at iso 225 and increase the shutter speed by 1 stop and still capture the same noise ( total light) as its DX brother but at a faster shutter speed.

Hmm. This is odd bc I have FF and crop lenses, and when I set them at the same apertures/FL/iso, the SS is identical.

F stop is really meaningless when comparing between formats as it only gauges the light intensity striking the sensor with 2 vastly different sensors dimensions.

Again, i disagree. F stop is not meaningless, it tells you how to find comparative SS between systems. What it doesn't tell you is how much noise you will get. Of course you get less noise with larger sensors, you are gathering more light. But putting a FF lens on a smaller sensor is wasting light. So no, it's not Ap dia that determines the total amount of light striking the sensor as your fist sentence above states, bc you don't mention sensor size. If i am wrong, please enlighten us all, explain why F stop even exists?

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Ian Stuart Forsyth
Ian Stuart Forsyth Veteran Member • Posts: 3,375
Re: FF Commentary by Thom
1

Ontario Gone wrote:

Bmoon wrote:

The F stop is only regulates the light intensity striking the sensor and its the Ap dia that determines the total amount of light striking the sensor and is really that what determines the shutter speed.

Let me back up here. What exactly do you mean by regulate? Everything I have ever read and heard suggests F stop is simply a way to gauge the exposure of a sensor. The lens determines how much light is let through, but the sensor size is what determines how much of that light gets absorbed. Does the entire industry have it wrong?

Many will argue that they can shoot DX at iso 100 F2.8 1/100sec and on ff iso100 2.8 1/100sec so that 2.8 lens n dx is as fast as the FF lens but they fail to see that the FF image captured 2.25 times more light so that image would contain lmore than half the noise so to equalize the total light striking the sensor one could shoot that FF at iso 225 and increase the shutter speed by 1 stop and still capture the same noise ( total light) as its DX brother but at a faster shutter speed.

Hmm. This is odd bc I have FF and crop lenses, and when I set them at the same apertures/FL/iso, the SS is identical.

What you are not quite getting and Brian Moon has told you more than once is that a FF Shot at Iso 100 F2.8 captures 2.25 times more light than a DX camera shot at iso 100 F2.8. one could shoot that FF image at iso 225 F2.8 and with a shutter speed 2.25 times fast and still capture the same total light, noise and DR of the Dx shot at iso 100 F2.8 and a SS 2.25 X slower.

F stop is really meaningless when comparing between formats as it only gauges the light intensity striking the sensor with 2 vastly different sensors dimensions.

Again, i disagree. F stop is not meaningless,

yes it is when you compare between to different formats

it tells you how to find comparative SS between systems. What it doesn't tell you is how much noise you will get. Of course you get less noise with larger sensors, you are gathering more light.

sure it is see below

But putting a FF lens on a smaller sensor is wasting light. So no, it's not Ap dia that determines the total amount of light striking the sensor as your fist sentence above states

do you know what AP dia is?

, bc you don't mention sensor size. If i am wrong, please enlighten us all, explain why F stop even exists?

Brian is correct Fstop is meaningless between formats what counts is the AP dia . and this is what determines the DOF, SS and total light striking the sensor

the reason why Brian brings up AP dia this is what governs SS, it has to do with the Total light falling on the sensor if one format at F2.8 gathers 2.25 times more light you can raise the shutter speed by 2.25 times and still capture the same total light, noise and DR as a DX camera shot at the same f stop

A FF image captured with a 50mm lens shot at F4.2 has an AP dia of 11.09mm while a DX image shot at 35mm F2.8 has a Ap dia of 12.05mm meaning they project the same total light and noise , and as the vast amount of grain we see in images these days come from the light its self we can say same amount of light = the same amount of noise.

the sum of this story is one can give up the 1 stop of noise performance the FF camera has over DX at a given Fstop and adjust the shutter speed 1 stop fast and still capture the same amount of light

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Ontario Gone
Ontario Gone Veteran Member • Posts: 4,183
Re: FF Commentary by Thom

Ian Stuart Forsyth wrote:

Brian is correct Fstop is meaningless between formats what counts is the AP dia . and this is what determines the DOF, SS and total light striking the sensor

Mark Ransom wrote:

Roland Karlsson wrote:

It is not the F-number that determines how fast a lens is, it is the aperture diameter.

Therefore, an F8 lens might be faster than an F2 lens, if the F8 lens camera is more than 4x bigger.

Not sure I understand. Doesn't "faster" in this context mean you can use a faster shutter speed for the same light level and exposure? That's independent of sensor size.

Keep in mind, Mark was asking about SS, light level, and exposure. He mentioned nothing about noise, for good reason, bc even noise varies among different sensors of the same format. You can't place the credit solely on the lens, bc it is the relation between the lens and sensor that is important. Of course FF gathers more light, everybody knows that. But the original question was about a lens being faster just bc it's a FF lens vs a crop lens, and that is misleading. The FF lens may have a larger aperture, but that is meaningless unless the sensor catches all the light.

Don't get me wrong, I understand very well the terms of aperture, I have spent much time studying telescopography and in that world, they don't usually mention F stops. They always refer to aperture. Why? BC there is not standard for sensor size. Many use CCD imagers, web cams, but it's a crap shoot.There is a reason the camera world does things differently. For example, how can you tell, if you were not studied in photography, which lens allowed faster SS:

Example 1: 50mm FF @ 25mm aperture

Example 2: 100mm FF @ 25mm aperture

Both shot on a FF camera fyi.

Now, anybody not knowing what the heck is going on will think you get the same SS from both, if they were to listen to the arguments here, but we know that's not true don't we. Why? BC the intensity drops off with longer FL. This is exactly why F stops are needed. Is it true a FF lens has a larger diameter than a crop, or MFT lens? Yes, but that doesn't matter. I'll prove it one more time.

Take a MF (medium format) lens and slap it on a FF camera. Take a crop lens and slap it on an apsc camera. Is the MF lens several stops faster than the crop lens, according to your standards? Yes. Are we using different sensor formats? yes. Will you get several stops of light more on the FF camera? No, perhaps 1.5. Going by lens diameter is hit or miss, bc its not the lens only, its the lens in relation to the sensor. Keep in mind, this is in line with your statement above, you said "Fstop is meaningless between formats, what counts is the AP dia". Here we have two different formats, yet the lens aperture differences won't reflect what we see in the photos.

F stop was created for a reason.

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