Full Frame Vs Crop Sensor

[sanj]

If you can take amazing pictures, then that makes you a photographer. Post-processing makes you an editor, and although thats what it takes to be photographer nowadays i.e. be both photographer & editor... It wasn't like that back in the day. And you have to agree...

Nope. Don't have to agree.

A photograph is a thing. The person who makes the thing is a photograph-er. The thing is not made until the image captured by the camera is made visible on the paper or other viewing surface. This "making" consists of the entire process from choosing/arranging/lighting the subject, adjusting/aiming/operating the camera and doing what one will to get it onto the paper. Ansel has already been mentioned as an example of a "back in the day" photograph-er who certainly made use of his dark room, his enlarger, and whatever other tools he chose, to create his "art". The photographs thusly made have been greatly admired by many, and few of the admirers fail to call him a "photographer", rather than an "editor". (Ansel the dodger/burner?)

Adams and the numerous other "photographers" one could mention as widely recognized and acclaimed, used the tools available to them in their time, just as we do today. I don't doubt that they would envy us our new tools.

It hardly seems appropriate to try to differentiate a carpenter from a measurer, a sawer or a hammerer. Perhaps we should further distinguish him as a laser level technician, an adhesives applier, or a plumb(vs. apple)-bobber.

Are we having fun yet?

Larry - I need to totally disagree with you. Photography is the skill of producing photographs. There is a big difference between a photograph and digital picture. "digital art" produces stunning pictures - which more often then not do NOT reflect anything real.

Photography as I understand it - is about recording a real moment or object in the most accurate way.

Yes I understand that some tweaks can be allowed - but these should be minor and unnoticeable. The "photo" should remain something real that the photographer saw. Photography is about VISION - NOT about enhanced photoshop / lightroom skills.

My 2 cents

Your understanding, as per my understanding, is totally wrong. Will find a photo I saw yesterday on this forum on a TS lens which was beautiful and far from accurate. Will find it and post next so you can see better.

Hi Sanj...thanks for posting that, not sure who shot it, did you? It is beautiful no doubt, but I will venture a criticism...the phrase I would use is "they got happy with the black slider a bit"...I admit it creates a lot of negative space which makes the rest "pop"...but true enough, it looks hyped and unnatural. If I were doing it, I would have some shadow detail, but try to let perhaps only 30 to 40% of what is total "black" here, be black. As for the hyped color, well that's typical of what people do with digital photos these days. This one is really not all that bad though.

Not my photo, I just put it there to make a point that photography is not only documentation but an art expression as well.

 

[Kit.]

Photography as I understand it - is about recording a real moment or object in the most accurate way.

Nope, that would be "journalism".

Photography is painting with light.

The philosophy down here is buy better glass before upgrading the body.

That's a leftover from the film era, when the body was mostly a light-tight box for your lenses and for your sensor (film), and no one caring about quality were shooting APS.

Now, an FF body will make your L lenses work better.

 

[CarlTN]

If you can take amazing pictures, then that makes you a photographer. Post-processing makes you an editor, and although thats what it takes to be photographer nowadays i.e. be both photographer & editor... It wasn't like that back in the day. And you have to agree...

Nope. Don't have to agree.

A photograph is a thing. The person who makes the thing is a photograph-er. The thing is not made until the image captured by the camera is made visible on the paper or other viewing surface. This "making" consists of the entire process from choosing/arranging/lighting the subject, adjusting/aiming/operating the camera and doing what one will to get it onto the paper. Ansel has already been mentioned as an example of a "back in the day" photograph-er who certainly made use of his dark room, his enlarger, and whatever other tools he chose, to create his "art". The photographs thusly made have been greatly admired by many, and few of the admirers fail to call him a "photographer", rather than an "editor". (Ansel the dodger/burner?)

Adams and the numerous other "photographers" one could mention as widely recognized and acclaimed, used the tools available to them in their time, just as we do today. I don't doubt that they would envy us our new tools.

It hardly seems appropriate to try to differentiate a carpenter from a measurer, a sawer or a hammerer. Perhaps we should further distinguish him as a laser level technician, an adhesives applier, or a plumb(vs. apple)-bobber.

Are we having fun yet?

Larry - I need to totally disagree with you. Photography is the skill of producing photographs. There is a big difference between a photograph and digital picture. "digital art" produces stunning pictures - which more often then not do NOT reflect anything real.

Photography as I understand it - is about recording a real moment or object in the most accurate way.

Yes I understand that some tweaks can be allowed - but these should be minor and unnoticeable. The "photo" should remain something real that the photographer saw. Photography is about VISION - NOT about enhanced photoshop / lightroom skills.

My 2 cents

Your understanding, as per my understanding, is totally wrong. Will find a photo I saw yesterday on this forum on a TS lens which was beautiful and far from accurate. Will find it and post next so you can see better.

Hi Sanj...thanks for posting that, not sure who shot it, did you? It is beautiful no doubt, but I will venture a criticism...the phrase I would use is "they got happy with the black slider a bit"...I admit it creates a lot of negative space which makes the rest "pop"...but true enough, it looks hyped and unnatural. If I were doing it, I would have some shadow detail, but try to let perhaps only 30 to 40% of what is total "black" here, be black. As for the hyped color, well that's typical of what people do with digital photos these days. This one is really not all that bad though.

Not my photo, I just put it there to make a point that photography is not only documentation but an art expression as well.

I thought so, just making sure...and a good point it was, especially since again, there are far more photos that commit worse transgressions than one like that, in my opinion.

 

[jdramirez]

That's a leftover from the film era, when the body was mostly a light-tight box for your lenses and for your sensor (film), and no one caring about quality were shooting APS.

Now, an FF body will make your L lenses work better.

I still agree with the sentiment... for 2 reasons... Lenses don't depreciate quickly... so you are better off running your body into the ground (150K of actuations) because it won't really be worth that much after a few years when you try and sell it. Point in case... the 1d iii which sold for $6K and is now selling for $1k. Whereas... if you bought a few nice lenses, you can still get well more than 16% of their original value.

And you can put an L lens on an older body and still get fantastic results... depending on what you are shooting. If it is landscape or portraiture, the advances in high iso performance and AF performance are minimized and you can still get some amazing images using an older XTi. Heck... if you are still rocking the t2i, there haven't really been that many advances along the lines of the crop sensors that would warrant buying a t5i.

When I sold my XS... it was a wash... when I sold my 60D, I lost $200 in depreciation... and when I sell my 5D mkiii, I will lose around $1000 in depreciation... which kills me. But maybe I avoid that by just using the mkiii until it dies in 10 years.

 

[wsmith96]

Glass before body: How many of you shoot 200-400mm 1.4X 4.0L with a 6.2mp Digital Rebel?

How many of you pros own one of those? :

 

[jdramirez]

Glass before body: How many of you shoot 200-400mm 1.4X 4.0L with a 6.2mp Digital Rebel?

How many of you pros own one of those? :

It is on my to try list... I 'd mull it over if it can ever be found in the $6000 to $7000 range.

 

[ecka]

The philosophy down here is buy better glass before upgrading the body.

That's a leftover from the film era, when the body was mostly a light-tight box for your lenses and for your sensor (film), and no one caring about quality were shooting APS.

Now, an FF body will make your L lenses work better.

I still agree with the sentiment... for 2 reasons... Lenses don't depreciate quickly... so you are better off running your body into the ground (150K of actuations) because it won't really be worth that much after a few years when you try and sell it. Point in case... the 1d iii which sold for $6K and is now selling for $1k. Whereas... if you bought a few nice lenses, you can still get well more than 16% of their original value.

And you can put an L lens on an older body and still get fantastic results... depending on what you are shooting. If it is landscape or portraiture, the advances in high iso performance and AF performance are minimized and you can still get some amazing images using an older XTi. Heck... if you are still rocking the t2i, there haven't really been that many advances along the lines of the crop sensors that would warrant buying a t5i.

When I sold my XS... it was a wash... when I sold my 60D, I lost $200 in depreciation... and when I sell my 5D mkiii, I will lose around $1000 in depreciation... which kills me. But maybe I avoid that by just using the mkiii until it dies in 10 years.

If you can throw $10'000 on glass, but you cannot justify spending more than $500 on a body, then you are being unreasonable. APSC sensors are only using 40% of the L glass potential. Even if you only got 3 or 4 lenses and use them / love them equally, then each one will only get a quarter of your attention, while the body is used for 100% of the time. If you worry so much about the resale value, then why not buying used bodies? I'm sure about one thing - I should have bought a used 5D with 50/1.8'II instead of a Rebel with some zooms (for the same price). Yes, I'm not one of those "covering the range" people.
I think that there is a conflict between two topics - "lenses before body" and "FF vs Crop" - which shouldn't be merged. However, when they do merge we get "$10'000 of L before FF" which sounds like "marriage without sex", or "FF with only $8000 of L" which sounds like fun (and the right way to do it), or "FF before any L" which sounds like "sex before marriage" (kinda fun too , for a hobby).

 

[jdramirez]

If you can throw $10'000 on glass, but you cannot justify spending more than $500 on a body, then you are being unreasonable. APSC sensors are only using 40% of the L glass potential. Even if you only got 3 or 4 lenses and use them / love them equally, then each one will only get a quarter of your attention, while the body is used for 100% of the time. If you worry so much about the resale value, then why not buying used bodies? I'm sure about one thing - I should have bought a used 5D with 50/1.8'II instead of a Rebel with some zooms (for the same price). Yes, I'm not one of those "covering the range" people.
I think that there is a conflict between two topics - "lenses before body" and "FF vs Crop" - which shouldn't be merged. However, when they do merge we get "$10'000 of L before FF" which sounds like "marriage without sex", or "FF with only $8000 of L" which sounds like fun (and the right way to do it), or "FF before any L" which sounds like "sex before marriage" (kinda fun too , for a hobby).

I don't think I was saying you should never upgrade your body... but with limited funds and the presumption of good light, you will be better off with a crop sensor plus s good L lenses versus a full frame and a 28-135.

Not to long ago a guy was asking if he should get a5d mkiii to pair with his 70-300... and everyone but me said Heck yes... I don't know if I'm clairvoyant, but I eventually got it out of him that his lens was a 75- 300, which is one of the worst lenses canon makes.

So with the money, I'd rather spend 3000 on a 24-105, a t3i, a 70-200 f4L IS, and a 580 ex ii over the full frame alternative. And with my math... I still have enough for a tokina wide angle or some nice primes...

Full frame is great... but you really should have some lenses to complement it.

As for resale value... yeah... that's the only way I can afford being in photography.

If I buy a lens for 1000, use it for 3 years and then sell it for 850, then I rented the lens for $50 per year... which in my opinion ifs well worth the effort. But more often than not, I buy a lens for 700, and sell it for 850... so they pay me $50 a year to keep their lens warn and in good condition. And I'm happy to oblige.

 

[mackguyver]

As for resale value... yeah... that's the only way I can afford being in photography.

If I buy a lens for 1000, use it for 3 years and then sell it for 850, then I rented the lens for $50 per year... which in my opinion ifs well worth the effort. But more often than not, I buy a lens for 700, and sell it for 850... so they pay me $50 a year to keep their lens warn and in good condition. And I'm happy to oblige.

+1 on everything and the other hard lesson is that when you go to sell (Canon) lenses, you'll either make money, break even, or lose just a bit of money (10-20%). When you sell bodies, you will always lose money - usually 20-50% even if you keep it in mint condition. Better to upgrade a lens two or three times (i.e. 50 1.8>50 1.4>50 1.2) and upgrade your body once (T3i>5DIII) then the other way around.

 

[ecka]

If you can throw $10'000 on glass, but you cannot justify spending more than $500 on a body, then you are being unreasonable. APSC sensors are only using 40% of the L glass potential. Even if you only got 3 or 4 lenses and use them / love them equally, then each one will only get a quarter of your attention, while the body is used for 100% of the time. If you worry so much about the resale value, then why not buying used bodies? I'm sure about one thing - I should have bought a used 5D with 50/1.8'II instead of a Rebel with some zooms (for the same price). Yes, I'm not one of those "covering the range" people.
I think that there is a conflict between two topics - "lenses before body" and "FF vs Crop" - which shouldn't be merged. However, when they do merge we get "$10'000 of L before FF" which sounds like "marriage without sex", or "FF with only $8000 of L" which sounds like fun (and the right way to do it), or "FF before any L" which sounds like "sex before marriage" (kinda fun too , for a hobby).

I don't think I was saying you should never upgrade your body... but with limited funds and the presumption of good light, you will be better off with a crop sensor plus s good L lenses versus a full frame and a 28-135.

Not to long ago a guy was asking if he should get a5d mkiii to pair with his 70-300... and everyone but me said Heck yes... I don't know if I'm clairvoyant, but I eventually got it out of him that his lens was a 75- 300, which is one of the worst lenses canon makes.

So with the money, I'd rather spend 3000 on a 24-105, a t3i, a 70-200 f4L IS, and a 580 ex ii over the full frame alternative. And with my math... I still have enough for a tokina wide angle or some nice primes...

Full frame is great... but you really should have some lenses to complement it.

As for resale value... yeah... that's the only way I can afford being in photography.

If I buy a lens for 1000, use it for 3 years and then sell it for 850, then I rented the lens for $50 per year... which in my opinion ifs well worth the effort. But more often than not, I buy a lens for 700, and sell it for 850... so they pay me $50 a year to keep their lens warn and in good condition. And I'm happy to oblige.

Somehow most people think that FF is only better for low light and that it is the only advantage over APSC (or maybe they don't care about the rest), while there is actually much more than that (at least 2.5x more). Same people are most likely to support the in-camera JPG propaganda, because they don't care about the difference. If you take 5 different cameras (different brands) and get it all right in camera for shooting the same scene, you'll still get 5 different photographs. Then what? Choose the one you like best and declare all the rest a blasphemy? But do you remember that you did everything right in each camera? That makes no sense. Let's do science, not religion. 24-105L on 6D won't scream "you need something wider!".

 

[jdramirez]

Boil it down. I think I understand what you are saying and then just as quickly I don't have a clue.

If you can throw $10'000 on glass, but you cannot justify spending more than $500 on a body, then you are being unreasonable. APSC sensors are only using 40% of the L glass potential. Even if you only got 3 or 4 lenses and use them / love them equally, then each one will only get a quarter of your attention, while the body is used for 100% of the time. If you worry so much about the resale value, then why not buying used bodies? I'm sure about one thing - I should have bought a used 5D with 50/1.8'II instead of a Rebel with some zooms (for the same price). Yes, I'm not one of those "covering the range" people.
I think that there is a conflict between two topics - "lenses before body" and "FF vs Crop" - which shouldn't be merged. However, when they do merge we get "$10'000 of L before FF" which sounds like "marriage without sex", or "FF with only $8000 of L" which sounds like fun (and the right way to do it), or "FF before any L" which sounds like "sex before marriage" (kinda fun too , for a hobby).

I don't think I was saying you should never upgrade your body... but with limited funds and the presumption of good light, you will be better off with a crop sensor plus s good L lenses versus a full frame and a 28-135.

Not to long ago a guy was asking if he should get a5d mkiii to pair with his 70-300... and everyone but me said Heck yes... I don't know if I'm clairvoyant, but I eventually got it out of him that his lens was a 75- 300, which is one of the worst lenses canon makes.

So with the money, I'd rather spend 3000 on a 24-105, a t3i, a 70-200 f4L IS, and a 580 ex ii over the full frame alternative. And with my math... I still have enough for a tokina wide angle or some nice primes...

Full frame is great... but you really should have some lenses to complement it.

As for resale value... yeah... that's the only way I can afford being in photography.

If I buy a lens for 1000, use it for 3 years and then sell it for 850, then I rented the lens for $50 per year... which in my opinion ifs well worth the effort. But more often than not, I buy a lens for 700, and sell it for 850... so they pay me $50 a year to keep their lens warn and in good condition. And I'm happy to oblige.

Somehow most people think that FF is only better for low light and that it is the only advantage over APSC (or maybe they don't care about the rest), while there is actually much more than that (at least 2.5x more). Same people are most likely to support the in-camera JPG propaganda, because they don't care about the difference. If you take 5 different cameras (different brands) and get it all right in camera for shooting the same scene, you'll still get 5 different photographs. Then what? Choose the one you like best and declare all the rest a blasphemy? But do you remember that you did everything right in each camera? That makes no sense. Let's do science, not religion. 24-105L on 6D won't scream "you need something wider!".

 

[ecka]

If you can throw $10'000 on glass, but you cannot justify spending more than $500 on a body, then you are being unreasonable. APSC sensors are only using 40% of the L glass potential. Even if you only got 3 or 4 lenses and use them / love them equally, then each one will only get a quarter of your attention, while the body is used for 100% of the time. If you worry so much about the resale value, then why not buying used bodies? I'm sure about one thing - I should have bought a used 5D with 50/1.8'II instead of a Rebel with some zooms (for the same price). Yes, I'm not one of those "covering the range" people.
I think that there is a conflict between two topics - "lenses before body" and "FF vs Crop" - which shouldn't be merged. However, when they do merge we get "$10'000 of L before FF" which sounds like "marriage without sex", or "FF with only $8000 of L" which sounds like fun (and the right way to do it), or "FF before any L" which sounds like "sex before marriage" (kinda fun too , for a hobby).

I don't think I was saying you should never upgrade your body... but with limited funds and the presumption of good light, you will be better off with a crop sensor plus s good L lenses versus a full frame and a 28-135.

Not to long ago a guy was asking if he should get a5d mkiii to pair with his 70-300... and everyone but me said Heck yes... I don't know if I'm clairvoyant, but I eventually got it out of him that his lens was a 75- 300, which is one of the worst lenses canon makes.

So with the money, I'd rather spend 3000 on a 24-105, a t3i, a 70-200 f4L IS, and a 580 ex ii over the full frame alternative. And with my math... I still have enough for a tokina wide angle or some nice primes...

Full frame is great... but you really should have some lenses to complement it.

As for resale value... yeah... that's the only way I can afford being in photography.

If I buy a lens for 1000, use it for 3 years and then sell it for 850, then I rented the lens for $50 per year... which in my opinion ifs well worth the effort. But more often than not, I buy a lens for 700, and sell it for 850... so they pay me $50 a year to keep their lens warn and in good condition. And I'm happy to oblige.

Somehow most people think that FF is only better for low light and that it is the only advantage over APSC (or maybe they don't care about the rest), while there is actually much more than that (at least 2.5x more). Same people are most likely to support the in-camera JPG propaganda, because they don't care about the difference. If you take 5 different cameras (different brands) and get it all right in camera for shooting the same scene, you'll still get 5 different photographs. Then what? Choose the one you like best and declare all the rest a blasphemy? But do you remember that you did everything right in each camera? That makes no sense. Let's do science, not religion. 24-105L on 6D won't scream "you need something wider!".

Boil it down. I think I understand what you are saying and then just as quickly I don't have a clue.

I'm saying that 6D+Sigma 35/1.4 (or even 35/2 IS USM) is much better than T2i+24L'II.

 

[jdramirez]

I love my primes... and I shot with a 50mm f1.8 for a year or two as my primary lens... but I'm not sure on what planet someone buys a 24 mm lens as their primary do it all lens alone. No zooms... no other primes... no flashes.

And I realize what sites through the view finder is comparable... but if you give me as a beginner a pile of cash... I don't think I will go out and buy a 24mm prime.

With that 1700 I can get a combination of the following depending on what I want to shoot:

Tokina 11-16
Canon 24-70 f2.8L
Sigma 35 art
Canon 50mm f1.4
A 100mm f2.8L is
A 135 f2L
A 70-200 f4L IS
A 430 or 580 ex speedlite...

Mix and match as much as you like... and you will have greater flexibility in your photographic efforts. True the images will not be quite as nice as a full frame alternative.

I might be doing a disservice to the 24mm, but it isn't about the individual maximization of the images as much add having the tools to get the images... and a crop will get you there until you have the coin for full frame.

I feel as though I missing something that needs to be said...

 

[jdramirez]

Also... I don't like the math of your example.

2650 for the 6d and the 35...
2150ish for the t2i and the 24mm...

Let's knock off 500 from the ful frame option and we are looking at a 35 f2 is.. and suddenly image quality starts to even out...

 

[ecka]

I love my primes... and I shot with a 50mm f1.8 for a year or two as my primary lens... but I'm not sure on what planet someone buys a 24 mm lens as their primary do it all lens alone. No zooms... no other primes... no flashes.

And I realize what sites through the view finder is comparable... but if you give me as a beginner a pile of cash... I don't think I will go out and buy a 24mm prime.

There are many. X100 has 35mm equivalent lens and people love it . EOS-M has 22mm prime lens which is 35mm equivalent too. I'm using 40STM pancake a lot and it is very close to 35mm. It is a very popular standard focal length. I agree that 24L is not the lens to begin with on crop (huge, heavy, expensive), but for "glass before body" kind of thinking it may be an option.

With that 1700 I can get a combination of the following depending on what I want to shoot:

Tokina 11-16
Canon 24-70 f2.8L
Sigma 35 art
Canon 50mm f1.4
A 100mm f2.8L is
A 135 f2L
A 70-200 f4L IS
A 430 or 580 ex speedlite...

Mix and match as much as you like... and you will have greater flexibility in your photographic efforts. True the images will not be quite as nice as a full frame alternative.

Ok, but I choose quality over quantity. I don't need to "cover the range" and it is only one L lens less for FF, really. What you'd get from your list on APSC is:
Tokina 18-26/4.5
Canon 38-112/4.5
Sigma 56/2.2
Canon 80/2.2
A 160/4.5 IS
A 216/3.5
A 112-320/6.3 IS
Nothing impressive for the price . I have a friend who decided to add a FF camera, so he would have twice more camera/lens combinations with his current lens collection (L zooms mostly), but now I see that he is not using his 550D anymore. 5D3 is so much better, he says . Now I have to convince him to shoot RAW .

I might be doing a disservice to the 24mm, but it isn't about the individual maximization of the images as much add having the tools to get the images... and a crop will get you there until you have the coin for full frame.

I feel as though I missing something that needs to be said...

Also... I don't like the math of your example.

That's just one of many possible examples, like FF+85/1.8USM vs Crop+50L, or FF+135L vs Crop+85L

2650 for the 6d and the 35...
2150ish for the t2i and the 24mm...

Well, you can get a used 5D2 for as low as 1k these days. My point is that you can get a much better combo for just a few hundred $ extra.

Let's knock off 500 from the full frame option and we are looking at a 35 f2 is.. and suddenly image quality starts to even out...

 

[jdramirez]

I don't begrudge people the whole field of view argument with crop v. full because a 50mm is indeed like an 85mm... and I'm not sure why, but with full frame, depth of field is greater, though with comparable framing, the full frame's depth of field is thinner...

I've heard the argument about the f/2.8 is comparable to f/4.5 (or whatever), but I didn't bother to ask what they meant.

So if I'm shooting with a 135L f/2 in moderate light and at iso 800 I'm shooting at 1/2000 of a second... that should still be the same achieved shutter speed regardless of crop or full.

And if you keep the same distance between, the depth of field should be comparable. So why is f/1.4 now f/2.2?

Ok, but I choose quality over quantity. I don't need to "cover the range" and it is only one L lens less for FF, really. What you'd get from your list on APSC is:
Tokina 18-26/4.5
Canon 38-112/4.5
Sigma 56/2.2
Canon 80/2.2
A 160/4.5 IS
A 216/3.5
A 112-320/6.3 IS

 

[philmoz]

And if you keep the same distance between, the depth of field should be comparable. So why is f/1.4 now f/2.2?

DoF is dependant on the 'circle of confusion' (CoC) of the sensor, which is determined by the sensor pixel size.
Smaller sensors pixels have smaller CoC so the DoF will be narrower - all else being equal.

http://en.wikipedia.org/wiki/Circle_of_confusion

Phil.

 

[privatebydesign]

Pixel size has absolutely nothing to do with coc.

 

[philmoz]

Pixel size has absolutely nothing to do with coc.

Doh (temporary brain freeze), of course you are correct - I meant to say sensor size (post updated).

Phil.

 

[privatebydesign]

I don't begrudge people the whole field of view argument with crop v. full because a 50mm is indeed like an 85mm... and I'm not sure why, but with full frame, depth of field is greater, though with comparable framing, the full frame's depth of field is thinner...

I've heard the argument about the f/2.8 is comparable to f/4.5 (or whatever), but I didn't bother to ask what they meant.

So if I'm shooting with a 135L f/2 in moderate light and at iso 800 I'm shooting at 1/2000 of a second... that should still be the same achieved shutter speed regardless of crop or full.

And if you keep the same distance between, the depth of field should be comparable. So why is f/1.4 now f/2.2?

Ok, but I choose quality over quantity. I don't need to "cover the range" and it is only one L lens less for FF, really. What you'd get from your list on APSC is:
Tokina 18-26/4.5
Canon 38-112/4.5
Sigma 56/2.2
Canon 80/2.2
A 160/4.5 IS
A 216/3.5
A 112-320/6.3 IS

Because the only fair comparison between the two images is two same sized images, to get a same sized image you have to enlarge the crop camera image more, in this instance, same lens, same settings, different framing but same sized output, the crop camera image has less dof.

People have to get it in their heads that dof is subjective and the only factors that affect it are aperture, as in the actual size of the aperture, not he number, and magnification. Make something bigger and it has less dof. Use a shorter lens from the same place and it has more dof because the same aperture value is a smaller physical size on the shorter lens and this more than overcomes the additional enlargement factor.