Please stop promoting crop sensors for the "extra reach"

[Ysarex]

Deeper depth of field (nope just crop a FF image and you have exactly the same).

We've been through this many times before. DOF changes with format size. You get more DOF from a smaller sensor. If you crop a FF sensor so it's the same size as a crop sensor then you're comparing a crop sensor with a crop sensor -- Duuuuuh.

Joe

 

[TheStunch]

i know that this was glossed over, but my canon sl1 is WAY smaller than a typical ff camera, which makes it better suited for my tastes, im just saying. plus cost. crop vs ff, crop is cheap, and the advantages of ff do not outweigh their significant cost increase for me. crop all day baby.

 

[goodguy]

My friend who is a pro fotog with years working for top agencies and papers tells me that for the life of it he can not understand amateurs buying full frame cameras.

Tell your friend for the low light performance!
Now after I am enjoying it I want more, much more low light performance, I am greedy, the sweeter my tea is the sweeter I want it to be

 

[sashbar]

I think i choked on my popcorn, you are right and I must be reading the wrong kind of articles.

I found a bit more mathematically geared draft that lays out the equations for depth of field in terms of Field of view and outside the box parameters. And apparently DOF can be larger, smaller, or the same for the same field of view on different formats. It just matters what you change, it probably warrants an entirely different thread. I'm apparently too tired for nuanced arguments tonight, I'll examine it later

No worries, this is one of the sources you can trust.

Digital Camera Sensor Sizes: How it Influences Your Photography

(I have quoted the DoF paragraph from here)

And if you have not yet seen it, this one is funny:

 

[Alexr25]

First up I don't like using the term "Crop sensor", it leads to some fuzzy and erroneous thinking as demonstrated above. It's like calling a 35mm film camera a crop camera because the film format is smaller than 120 or 4X5.

................. Suppose you have a crop sensor and a full frame sensor from the same generation and manufacturer with roughly the same pixel density.

As a rule same generation sensors have the same pixel count so the APS-C sensor being smaller than the full frame sensor must have a higher pixel density.
This is why full frame sensors have better noise and high ISO performance.

Some other supposed advantages of crop sensor and my criticism:

• Higher frame rate (what are you doing spraying and praying? It's not even an advantage if you go to the pro line.)
• Higher flash sync speed ( not always true. but congrats anyway you may gain 1/3 EV)
• Deeper depth of field (nope just crop a FF image and you have exactly the same).
• Better (or worse) bokeh ( this is a property of the lens, aperture, focal length and focus distance. If it's in frame it will be the same)

Ignoring the first 2 points which are nether important nor true we come to the old depth of field argument. This is the reason I hate the term crop sensor!

DoF was covered ad-nauseum in several resent threads so I don't propose to go into detail but I do suggest you read Depth of field - Wikipedia, the free encyclopedia and http://en.wikipedia.org/wiki/Circle_of_confusion.
If you read the text and study the equations you will see that a lens does not have an intrinsic depth of fields but rather the DoF is a property of the final viewable image and it depends on:
1. the lens focal length
2. the lens aperture
3. the lens to subject distance
4. the amount of magnification that was applied to the sensor image to produce the final viewable image. This affects the circle of confusion term in the DoF equation.

If you produce an image with the same subject and the same angle of view from both a full frame sensor and a APS-C sensor then the lens to subject distance will be different as will the magnification and hence the circle of confusion. Therefore the DoF cannot be the same!

The same argument applies to the point about bokeh (that is another term I dislike, I always think of it as the sound my cat makes when he brings of a fur-ball).

Being in photographer, especially if you want to do it professionally, is about managing your expenses. That's why we're not all running around with digital hasselblads or phase one cameras. Most of us don't need them enough to justify the cost.

My very feelings about full frame DSLRs!

 

[Village Idiot]

First and foremost DOF! Oh wait, is that the fifth or tenth time it's been rehashed in this thread...

 

[qleak]

If you produce an image with the same subject and the same angle of view from both a full frame sensor and a APS-C sensor then the lens to subject distance will be different as will the magnification and hence the circle of confusion. Therefore the DoF cannot be the same!

It's even a bit more complicated that this you're assuming that the f-number is constant right? I was looking at Dick Lyon's Draft page 8 number 4:

Scaling the f-number to have a constant absolute aperture diameter will result in the same DOF when you have the same FOV. Let's see if my 7:20am brain is processing this correctly

FF 100mm f2.8
APS-C 70mm f1.8

Should produce roughly the same DOF since 2.8/1.5 = 1.866667. In fact it should be a little shallower because of the 2/30 part of the fraction.

This is one of the things they bragged about in the Sigma 18-35mm f1.8 DX lens(that I purchased) and don't think I understood until now. It has an equivalently shallow depth of field as a 27-52.5mm f2.8 FF lens.

 

[qleak]

As a rule same generation sensors have the same pixel count so the APS-C sensor being smaller than the full frame sensor must have a higher pixel density.
This is why full frame sensors have better noise and high ISO performance.

This also appears to be true at the FF / MF as well:

Nikon D810 vs. Pentax 645Z - Sensor Comparison

Apparently it's way to costly to manufacture a defect free high pixel count sensor of a larger size for a given fixed production process.

 

[qleak]

And if you have not yet seen it, this one is funny:

Yes quite amusing.

I think this whole post is a result in my frustration with the whole hubbub between things that are not that different. I got a little carried away and started assuming things that are not true.

If you assume one false proposition you can prove every proposition. i really went for the brass ring

 

[Ysarex]

If you produce an image with the same subject and the same angle of view from both a full frame sensor and a APS-C sensor then the lens to subject distance will be different as will the magnification and hence the circle of confusion. Therefore the DoF cannot be the same!

It's even a bit more complicated that this you're assuming that the f-number is constant right? I was looking at Dick Lyon's Draft page 8 number 4:

Scaling the f-number to have a constant absolute aperture diameter will result in the same DOF when you have the same FOV. Let's see if my 7:20am brain is processing this correctly

FF 100mm f2.8
APS-C 70mm f1.8

Should produce roughly the same DOF since 2.8/1.5 = 1.866667. In fact it should be a little shallower because of the 2/30 part of the fraction.

This is one of the things they bragged about in the Sigma 18-35mm f1.8 DX lens(that I purchased) and don't think I understood until now. It has an equivalently shallow depth of field as a 27-52.5mm f2.8 FF lens.

What you need to do however is a comparison and not and adjustment for variation. In other words you just said that if you make an adjustment for differences in the two formats you can get the same result from both; and again I say, duuuuuuh! You're saying to a photographer, "Here use this crop sensor camera and you'll get the same results as you do with a FF sensor camera as long as you make these compensation adjustments first."

Now do a comparison. To do any kind of meaningful comparison you need to use the two different format cameras to take the same photograph. The adjustments you need to make between the two format cameras should be adjustments so that you have a meaningful comparison by taking the same photograph with both cameras. If you do that, if you in fact COMPARE in use a crop sensor and FF sensor camera, the smaller format camera will have more DOF which is a well established fact.

Joe

 

[Ysarex]

And if you have not yet seen it, this one is funny:

Yes quite amusing.

I think this whole post is a result in my frustration with the whole hubbub between things that are not that different. I got a little carried away and started assuming things that are not true.

If you assume one false proposition you can prove every proposition. i really went for the brass ring

Difference is a good thing, it gives you choice. The format differences are real and become increasingly meaningful as you make bigger jumps from one point to another on the scale. APSC and FF are adjacent on the scale. I use a compact all the time that has a 1/1.7 sensor. The differences between my compact and FF are pretty substantial. Difference doesn't have to mean better/worse. My compact takes really good photos but I have to be aware of it's capabilities and limitations. It fits in my jacket pocket and goes everywhere I go. Because it's always with me it's my most used camera -- that's good.

Am I ever out somewhere with my little compact and realize it's just not up to the task and wish I had brought along my 4x5. Sure, but today when I go out I'll take my compact again.

Joe

 

[sashbar]

And if you have not yet seen it, this one is funny:

Yes quite amusing.

I think this whole post is a result in my frustration with the whole hubbub between things that are not that different. I got a little carried away and started assuming things that are not true.

If you assume one false proposition you can prove every proposition. i really went for the brass ring

Difference is a good thing, it gives you choice. The format differences are real and become increasingly meaningful as you make bigger jumps from one point to another on the scale. APSC and FF are adjacent on the scale. I use a compact all the time that has a 1/1.7 sensor. The differences between my compact and FF are pretty substantial. Difference doesn't have to mean better/worse. My compact takes really good photos but I have to be aware of it's capabilities and limitations. It fits in my jacket pocket and goes everywhere I go. Because it's always with me it's my most used camera -- that's good.

Am I ever out somewhere with my little compact and realize it's just not up to the task and wish I had brought along my 4x5. Sure, but today when I go out I'll take my compact again.

Joe

If you like quality compacts, try Ricoh GR. I love this little camera. Good APS-C Sony sensor, excellent controls, crazy sharp lense, rugged excellent body. The IQ is impressive. And it fits a shirt or a loose jeans pocket, never mind a jacket.

What I like about the current choice - unlike some years ago there are no more "photographic quality" and "poor snapshot quality" cameras, all properly constructed cameras are good, they are just different, suited for different purposes. There is still some difference in image quality, but all good cameras have either surpassed or come close to the IQ threshold where the IQ differences are becoming negligible in many applications.

 

[Overread]

Ysarex - from what I recall in macro talks the difference between your average 1.6/5 crop and fullframe in depth of field is about one stops worth of aperture. Fullframe bodies can oft also close down one more stop of aperture before diffraction takes effect as strongly - plus they tend to (these days) have a wider useable ISO range.

So in theory you can up the ISO - close down the aperture and get a similar depth of field on fullframe.

 

[Umberrella]

Mind sharing your popcorn? I have spend my money on another FF..

What is better... depends on your needs. I work with both for whatever will suit best for the assignment. Sometimes my distance between me and subject is not to be changed and the lenses are not zooming in any further to get that frame filled enough. Crop camera saves me time in editing when time is very limited.

 

[rexbobcat]

Except that an 18 MP crop sensor will out-resolve a similar crop from a full frame camera.

The only way this isn't true is if your full frame camera has a crazy amount of MP, like with the Phase Ones and D800, and even then, you'll have more noise from the FF crop.