L Lenses for crop bodies

[rs]

Are you saying thats a 1x vs 1.6x crop?

Not at all; its just to illustrate that different fields of view (whether via a different crop or a different focal length) produce a different composition.

Composition means more than framing.

I fully agree. However, all I'm trying to illustrate is field of view is one of the elements which make up composition.

I'll re-quote myself:

Without changing the elements that make up the scene, composition is purely a combination of camera placement and field of view. To keep the composition the same, those two elements have to stay the same. Which means if you switch sensor size, the focal length has to change accordingly to maintain the composition.

 

[sdsr]

the 2nd lens on the list: sigma 18-35

you can see that the overall scores are pretty close on the 2 combos, the ff combo is sharper but both combos are plenty sharp and will give you good results with similar dof.

the ff combo is $5700 the aps-c combo is $2100

It would be more useful to see side-by-side photos of actual things; they may (or may not) look much the same, depending on the subject, how the photo is displayed, etc. But see this:

http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=854&Camera=736&Sample=0&FLI=4&API=0&LensComp=787&CameraComp=453&SampleComp=0&FLIComp=3&APIComp=0

And, more interesting perhaps, given your evident determination to find the most expensive FF gear, compare the Sigma with the Tamron 24-70 2.8 VC:

http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=854&Camera=736&Sample=0&FLI=4&API=0&LensComp=786&CameraComp=0&FLIComp=0&APIComp=0

or, less expensive still (around the same price as the Sigma 18-35), the Sigma 24-70 2.8

http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=854&Camera=736&Sample=0&FLI=4&API=0&LensComp=805&CameraComp=0&FLIComp=0&APIComp=0

To the extent that such photos are revealing, the FF all look quite a bit sharper to me.

 

[sdsr]

The Sigma is sharper at f1.8 than the 70-200mm f2.8 IS II is at f2.8, so I'm guessing it's the best zoom on APS-C unless the 24-70mm f2.8 II is dramatically better than the 70-200.

Is it sharper than the 70-200 on crop?

http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=854&Camera=736&Sample=0&FLI=0&API=0&LensComp=687&CameraComp=736&SampleComp=0&FLIComp=0&APIComp=0

And it only seems to be sharper wide open than the 24-70II in the corners at its shortest focal lenght, and advantage that seems to go away as the focal length increases.

http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=854&Camera=736&FLI=0&API=0&LensComp=787&Sample=0&SampleComp=0&CameraComp=736&FLIComp=0&APIComp=0

That said, I suspect there's little if any difference in real life (though of course 1.8 is much more useful on a crop body than 2.8 for other reasons). If you switch bodies to FF in those comparisons for the Canon lenses, the result is more than subtly different.

 

[wickidwombat]

As the lines between FF and crop continue to blur - and we are seeing very high performance crop bodies - I am hoping canon will invest in high quality lenses for crop bodies. Why not L lenses for crops ? There is no good wide angle prime lens options for crop (outside third party lenses) this is a pity.

I haven't seen these high performance crop bodies of which you speak!

 

[candc]

the 2nd lens on the list: sigma 18-35

you can see that the overall scores are pretty close on the 2 combos, the ff combo is sharper but both combos are plenty sharp and will give you good results with similar dof.

the ff combo is $5700 the aps-c combo is $2100

, given your evident determination to find the most expensive FF gear,

if i was trying to show the most expensive ff gear i would be pointing to the 1dx but i think most would agree that the iq of the 5d3 is as good or better than the 1dx? i know the resolution is better on the 5diii

 

[Pi]

the 2nd lens on the list: sigma 18-35

you can see that the overall scores are pretty close on the 2 combos, the ff combo is sharper but both combos are plenty sharp and will give you good results with similar dof.

the ff combo is $5700 the aps-c combo is $2100

You are kidding, right - or just trolling? Comparing the 24-70II on FF vs. whatever on crop?

 

[candc]

the 2nd lens on the list: sigma 18-35

you can see that the overall scores are pretty close on the 2 combos, the ff combo is sharper but both combos are plenty sharp and will give you good results with similar dof.

the ff combo is $5700 the aps-c combo is $2100

You are kidding, right - or just trolling? Comparing the 24-70II on FF vs. whatever on crop?

i am neither kidding or trolling and yes that is exactly what i am comparing as does this review of the lens

http://www.slrlounge.com/sigma-18-35mm-f1-8-ex-dc-field-review

go ahead and read it if you like but be careful there may some language in the article you don't like.

such as:

" While certain elitists are quick to dismiss crop-sensor lenses, I’m a lot more open-minded"

and

"However what most “FF fanboys” fail to do is, compare the entire system and overall long-term costs. And that way, any way you slice it, full-frame becomes more expensive than crop-sensors by $1,000-$3,000 or more"

 

[Pi]

i am neither kidding or trolling and yes that is exactly what i am comparing as does this review of the lens

OK, so you are trolling.

http://www.slrlounge.com/sigma-18-35mm-f1-8-ex-dc-field-review

go ahead and read it if you like but be careful there may some language in the article you don't like.

such as:

" While certain elitists are quick to dismiss crop-sensor lenses, I’m a lot more open-minded"

and

"However what most “FF fanboys” fail to do is, compare the entire system and overall long-term costs. And that way, any way you slice it, full-frame becomes more expensive than crop-sensors by $1,000-$3,000 or more"

BS. The Sigma 24-70 is about the same price as the 18-35, it is wider, it has a longer reach, and makes the images of the 18-35 look like taken with an iphone.

Speaking about the entire system (this is not a fixed lens camera, right?), the cheapo 50/1.4 on FF makes the 35L on crop look like Coca-Cola glass:

http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=121&Camera=736&FLI=0&API=0&LensComp=115&CameraComp=453&SampleComp=0&FLIComp=0&APIComp=3

 

[candc]

anyway,

the op was asking about L lenses for crop bodies. i listed what i think is the best zoom lens lineup available for aps-c bodies

if your still here i hope that helps

 

[Rienzphotoz]

"However what most “FF fanboys” fail to do is,

I've heard of Canon fanboys, Nikon fanboys, iSheep, Shamesung fandroids etc etc, but I was not aware that there are sub-categories within the same fanboy group ;D
I am glad that I escaped this accusation as I have a FF camera and a APS-C camera ;D

 

[paul13walnut5]

@rs misread your previous post, apologies.

 

[Loswr]

Similar to saying FF gives shallower DoF, which is misleading when explaining to newbies because the shallower DoF is from the consequence of changing the composition (FL and/or focus distance).

It's not misleading, IMO - it's a logical simplification. First, someone should understand the what, then the why. In a dark room, do you launch into an explanation of the principles of electricity, or do you simply show someone how to flip the light switch?

On a broader note anyone notice how conveniently people switch between a dependence on the lens vs dependence on the body?

If talking about reach, people are gladly happy to say the image projected by the lens remains the same thus it is nothing more than faux reach via an optical crop and there is no real extra reach. True and I agree with that, even though yes reach is about pixel densities rather than optical reach per se.

If talking about sharpness, suddenly it's all on the body; despite the fact it's the same thing where the image projected by the lens has not changed thus absolute sharpness from the image also does not change.

I don't deny in an absolute final image sense the image is better, but the candy being sold is a little disingenuous.

The reality is that both body and lens matter, obviously. Which one is more important depends on what is being captured. When talking about reach, the sensor with the higher pixel density will put more pixels on target. That's usually the crop sensor, with current bodies (but the D800 has a higher pixel density than the T3, for example). There's no significant IQ difference between the APS-C image and the FF image cropped to the smaller AoV, at low ISO. At high ISO (above ~800, and a lot of bird/wildlife photography where focal length is limiting requires high ISO), the cropped FF image will deliver better IQ. Current Canon FF sensors cropped to APS-C FoV yield 7-8.6 MP, which is sufficient for at least 16x24" prints. So, unless you're printing larger, the 'reach advantage' of APS-C is an illusion. Even if you're printing larger, a shot at high ISO will likely look better from the FF camera.

The FF sensor will be much sharper when the same lens is used, sharper if a slightly inferior lens is used, and a not so good lens on FF will still usually equal an excellent lens on APS-C. If you aren't focal length limited, APS-C offers no significant advantage in terms of IQ (unless you think reduced 'cats-eye' bokeh on FF lenses which exhibit it is significant).

Obviously there's a cost advantage to APS-C bodies and lenses, but anyone who claims an advantage based on the sensor outside of low ISO focal length limited situations (where IQ is similar but APS-C delivers more MP) is confused or incorrect.

 

[Sporgon]

Can someone exain this puzzle to me.

As Neuro has stated above, given cropping of two equally dense sensors of different sizes ( FF & APS ) the larger retains it's benefit of better high ISO performance even when cropped to APS. Presumably this is because there was more light originally on the larger sensor.

When you put say a 135L onto a crop sensor camera, the sensor is only recording about half the area of the image circle from that lens, and so half the light. Due to the difference in circle of confusion that f2 less now produces results in dof terms to (something like) an f3.2 lens.

So why is it that the exposure for that f2 lens remains the same as on a FF camera when the whole of the image circle is being recorded ( or much of it). And it does, even using a separate light meter f2 on the APS camera gives exactly the same exposure via the histogram as a FF camera. Yet the APS is not recording the same amount of light !

How can this be when a FF retains it's high iso performance e en when cropped. ???

 

[Pi]

How can this be when a FF retains it's high iso performance e en when cropped. ???

Well, it does not.

 

[candc]

Can someone exain this puzzle to me.

As Neuro has stated above, given cropping of two equally dense sensors of different sizes ( FF & APS ) the larger retains it's benefit of better high ISO performance even when cropped to APS. Presumably this is because there was more light originally on the larger sensor.

When you put say a 135L onto a crop sensor camera, the sensor is only recording about half the area of the image circle from that lens, and so half the light. Due to the difference in circle of confusion that f2 less now produces results in dof terms to (something like) an f3.2 lens.

So why is it that the exposure for that f2 lens remains the same as on a FF camera when the whole of the image circle is being recorded ( or much of it). And it does, even using a separate light meter f2 on the APS camera gives exactly the same exposure via the histogram as a FF camera. Yet the APS is not recording the same amount of light !

How can this be when a FF retains it's high iso performance e en when cropped. ???

The d800 has a DX function which just uses the aps-c portion of the sensor, there is no change in exposure. A shot with the same lens taken in DX mode or one taken in ff mode and later cropped to aps-c size will be the same

 

[Loswr]

When you put say a 135L onto a crop sensor camera, the sensor is only recording about half the area of the image circle from that lens, and so half the light. Due to the difference in circle of confusion that f2 less now produces results in dof terms to (something like) an f3.2 lens.

The deeper DoF on APS-C has nothing to do with CoC. Compared to FF, to get the same framing on APS-C you must use a shorter focal length or move further away. Either will results in deeper DoF.

If you use the same focal length and distance (and aperture) on both formats, the FoV will be smaller on APS-C, of course, but the DoF will actually be slightly shallower - that's the effect of the difference in CoC.

So why is it that the exposure for that f2 lens remains the same as on a FF camera when the whole of the image circle is being recorded ( or much of it). And it does, even using a separate light meter f2 on the APS camera gives exactly the same exposure via the histogram as a FF camera. Yet the APS is not recording the same amount of light !

How can this be when a FF retains it's high iso performance e en when cropped. ???

Total light gathered determines image noise, light per unit area determines exposure. Thus, f/2 on FF and f/2 on a PowerShot S100 at the same ISO will have the same (metered) shutter speed.

The cropped FF image doesn't fully retain its noise advantage - that advantage is 1.3-stops based on the area difference, but in practice it's 1.5-2 stops. At ISO 800 and lower, there's really no difference between APS-C and cropped FF (there's a little less noise in the cropped FF at those low ISOs, but more detail in the APS-C, so NR or sharpening will trade one for the other). As you go to progressively higher ISOs, the cropped FF has a progressive advantage - pretty subtle at ISO 1600, visible at ISO 3200, significant at ISO 12800, etc. Obviously, if you don't have to crop, the full advantage is retained.

 

[paul13walnut5]

Presumably this is because there was more light originally on the larger sensor.

I think a comparison would only be valid like for like, i.e. the subject light would be the same and the projected image circle would be the same at the focal plane regardless of the sensor area, otherwise a comparison would be meaningless. The larger sensor has larger individual photosites is the key.

 

[Pi]

The larger sensor has larger individual photosites is the key.

It is more like a footnote.

 

[paul13walnut5]

Do a car analogy. From Hogmany its my new years resolution to only deal in metaphors if they involve cars.
What would a footnote be in a car?

 

[Pi]

Do a car analogy. From Hogmany its my new years resolution to only deal in metaphors if they involve cars.
What would a footnote be in a car?

It is like saying that engines with higher volume are more powerful because they have larger cylinders.