Lens Hype, What is really a good lens?

[dennybeall]

Bokeh is a tool used by photographers just like their other tools. When you know your tool you can use a background that looks right for the shot you want. One color or many with lights or not and select the distance.

 

[Ysarex]

many people go out and buy an expensive lens for the wrong reasons, many will go out and buy lets say a Nikon 70-200 2.8 thinking ok they are oging to get sharp pictures and good bokah..
Bokah is a FAD people getting all hyped up thinking the only good portrait is a bokah one, meaning blur the background, but that is simply not true.

First off let me tell you the reason a background may get bokah, (blur) it has to do with many factors, not just a small number aperture like 1,8 or 2.8 it's about how close you are to your subject, and how close your subject is to the background as well, and also your focal length is if using a zoom lens and not a prime lens such as a 50mm 1.8..

First it's bokeh not bokah. Bokeh is not background blur as Tim has already noted. You're trying to write about a photographic phenomenon and you don't know what it is. The wiki definition is good: In photography, bokeh (originally /ˈboʊkɛ/,[1] /ˈboʊkeɪ/ BOH-kay — also sometimes pronounced as /ˈboʊkə/ BOH-kə,[2] Japanese: [boke]) is the aesthetic quality of the blur produced in the out-of-focus parts of an image produced by a lens. Bokeh is not the blur it's the visual character of the blur. This will help: Kiev Cameras

.....Now another factor that you need to know about Bokah , (blur) the background, is the sensor size, a full frame camera will be able to blur the background easier then using an APSC camera..

that is one of the reason that the background gets soft is because of the amount of light hitting the sensor, so if you got a full frame sensor then more light is factored in the image, rather then a APSC sensor. that is why lower aperture numbers give you a narrower depth of field, it lets more light in the image. so if you use f 3.5 on full frame sensor and use an f 3.5 on APSC sensor the full frame image is going to have more blur even at the same aperture setting.

This is incoherent nonsense. You don't get more blur from a FF sensor versus a crop sensor because the FF sensor "factors" more light in the image.

Joe

of course you would get more blur in the background with full frame vs crop sensor,

Did I say otherwise? Read carefully what I wrote and then show me where I said there isn't more blur. I said your reasoning for the difference is incoherent nonsense.

if i shoot a portrait using 2.8 with APSC and you do the same thing with 2.8 with a full frame the image with the full frame will have more exposure in it (more light)

You're saying that exposure at f/2.8 FF is different than exposure at f/2.8 crop sensor (ambient light and shutter speed the same). That would be nonsense. And that this supposed difference is somehow the cause for the difference in background blur. Which would also be nonsense.

your a liar if you say different , and here bokeh

Good job -- you got the spelling right.

is about blur in the background, here is an article about it, so i'm not the only one who says this..

Yep, your error has lots of company. Supporting your error with a reference to someone else making the same mistake just means you're both wrong.

Others can decide for them self what is correct.. lol

and yes sensor size effects the image differently at any aperture..



The Bokeh Effect: How Sensor Size Affects Background Blur

 

[robbins.photo]

Ok, so the very first thing I learned about bokeh. You never want to post anything about it to TPF. If you do you'll wind up in a hypertechnical discussion with dozens of posters attempting to one up each other to display their vast technical knowledge. There will corrections posted correcting corrections and it dissolves quickly into a complete cluster.

So, the first rule about bokeh? Don't talk about bokeh.

Sent from my N9518 using Tapatalk

 

[Ysarex]

and here bokeh is about blur in the background, here is an article about it, so i'm not the only one who says this..

The Bokeh Effect: How Sensor Size Affects Background Blur

I gave you a reference to a good article that defines bokeh correctly: Kiev Cameras
Here are definitions:
Oxford dictionary:
bokeh
Pronunciation: /bōˈkā/

noun
Photography
The visual quality of the out-of-focus areas of a photographic image, especially as rendered by a particular lens

Dictionary.com:
noun
a Japanese term for the subjective aesthetic quality of out-of-focus areas of a photographic image.

So now that we know the blog you referenced is also wrong you'd be advised to hold everything else they say suspect as well.

Joe

 

[donny1963]

many people go out and buy an expensive lens for the wrong reasons, many will go out and buy lets say a Nikon 70-200 2.8 thinking ok they are oging to get sharp pictures and good bokah..
Bokah is a FAD people getting all hyped up thinking the only good portrait is a bokah one, meaning blur the background, but that is simply not true.

First off let me tell you the reason a background may get bokah, (blur) it has to do with many factors, not just a small number aperture like 1,8 or 2.8 it's about how close you are to your subject, and how close your subject is to the background as well, and also your focal length is if using a zoom lens and not a prime lens such as a 50mm 1.8..

First it's bokeh not bokah. Bokeh is not background blur as Tim has already noted. You're trying to write about a photographic phenomenon and you don't know what it is. The wiki definition is good: In photography, bokeh (originally /ˈboʊkɛ/,[1] /ˈboʊkeɪ/ BOH-kay — also sometimes pronounced as /ˈboʊkə/ BOH-kə,[2] Japanese: [boke]) is the aesthetic quality of the blur produced in the out-of-focus parts of an image produced by a lens. Bokeh is not the blur it's the visual character of the blur. This will help: Kiev Cameras

.....Now another factor that you need to know about Bokah , (blur) the background, is the sensor size, a full frame camera will be able to blur the background easier then using an APSC camera..

that is one of the reason that the background gets soft is because of the amount of light hitting the sensor, so if you got a full frame sensor then more light is factored in the image, rather then a APSC sensor. that is why lower aperture numbers give you a narrower depth of field, it lets more light in the image. so if you use f 3.5 on full frame sensor and use an f 3.5 on APSC sensor the full frame image is going to have more blur even at the same aperture setting.

This is incoherent nonsense. You don't get more blur from a FF sensor versus a crop sensor because the FF sensor "factors" more light in the image.

Joe

of course you would get more blur in the background with full frame vs crop sensor,

Did I say otherwise? Read carefully what I wrote and then show me where I said there isn't more blur. I said your reasoning for the difference is incoherent nonsense.

if i shoot a portrait using 2.8 with APSC and you do the same thing with 2.8 with a full frame the image with the full frame will have more exposure in it (more light)

You're saying that exposure at f/2.8 FF is different than exposure at f/2.8 crop sensor (ambient light and shutter speed the same). That would be nonsense. And that this supposed difference is somehow the cause for the difference in background blur. Which would also be nonsense.

your a liar if you say different , and here bokeh

Good job -- you got the spelling right.

is about blur in the background, here is an article about it, so i'm not the only one who says this..

Yep, your error has lots of company. Supporting your error with a reference to someone else making the same mistake just means you're both wrong.

Others can decide for them self what is correct.. lol

and yes sensor size effects the image differently at any aperture..



The Bokeh Effect: How Sensor Size Affects Background Blur

Not an error, full frame vs APSC does effect exposure differently using the same situation , or should i say larger sensors have an advantage over smaller sensors with the amount of light, for instance a med format camera requires 28% less light then a full frame camera to get the same exposure with the same situation. same with full frame vs apsc ..

Intuitively, if you put the same lens with the same settings on both cameras, and if the distance from the lens to the sensor is the same in both cases, then the full frame sensor will collect more light because the sensor is larger and therefore covers more of the circle of light projected by the lens.
pretty simple physics and math, but maybe you and your friends was out skipping school when your teacher was explaining physics and math...

 

[Ysarex]

Ok, so the very first thing I learned about bokeh. You never want to post anything about it to TPF. If you do you'll wind up in a hypertechnical discussion with dozens of posters attempting to one up each other to display their vast technical knowledge. There will corrections posted correcting corrections and it dissolves quickly into a complete cluster.

So, the first rule about bokeh? Don't talk about bokeh.

Sent from my N9518 using Tapatalk

It's not rocket science, it's just simple stuff misunderstood by a vast army of Youtube vloggers and bloggers.

Joe

 

[The_Traveler]

your a liar if you say different , and here bokeh is about blur in the background, here is an article about it, so i'm not the only one who says this

1) Calling someone a liar over a disagreement in terms is really rude.
2) bokeh is not about the amount of blur but its quality.

 

[480sparky]

 

[donny1963]

Ok, so the very first thing I learned about bokeh. You never want to post anything about it to TPF. If you do you'll wind up in a hypertechnical discussion with dozens of posters attempting to one up each other to display their vast technical knowledge. There will corrections posted correcting corrections and it dissolves quickly into a complete cluster.

So, the first rule about bokeh? Don't talk about bokeh.

Sent from my N9518 using Tapatalk

yeah people are always trying to flex there vast technical knowledge, they think they are some sort of legend in there own time, more like Legend in there own mind lol..


i've posted proof to correct there inaccurate reply but they will just turn around and say something to defend it, like yeah they are many people wrong like you lol that was so funny. it's fun to watch some one in desperation fumble with a totally stupid remark,, lol

How ever any one with an IQ over 60 can determine reality vs ego fantasy lol

 

[donny1963]

your a liar if you say different , and here bokeh is about blur in the background, here is an article about it, so i'm not the only one who says this

1) Calling someone a liar over a disagreement in terms is really rude.
2) bokeh is not about the amount of blur but its quality.

well if they lie, then the words fit.. any one who knows anything about how photography works, knows that sensor size does effect how much light your getting.. to say that is not true is a lie,, i call it as i see, it, and i say lie because he has enough experience with photography to know what is true and a lie.

to be mistaken is one thing but to know what the truth is and to say other wise would be lie am i not right??
this is taught in general photography for beginners, and explained so many times and so many places to say otherwise is crazy.

 

[donny1963]

see these guys think they win every argument even when they are clearly wrong..

if there is a red pen sitting on a table and you draw a line to prove it's red they will still say it's blue....
these guys egos are so messed up that they believe there own inaccurate statements...

 

[Ysarex]

Not an error, full frame vs APSC does effect exposure differently using the same situation , or should i say larger sensors have an advantage over smaller sensors with the amount of light, for instance a med format camera requires 28% less light then a full frame camera to get the same exposure with the same situation. same with full frame vs apsc ..

And how exactly does that alter the degree of background blur?

But wait! Before you try and answer that please confirm this: Describe specifically this advantage in amount of light for a FF sensor. Your saying that at same ISO, shutter speed and ambient light with lenses at same AOV and both at f/2.8 the APSC camera will be exposed less than the FF. Yes or no?

Joe

Intuitively, if you put the same lens with the same settings on both cameras, and if the distance from the lens to the sensor is the same in both cases, then the full frame sensor will collect more light because the sensor is larger and therefore covers more of the circle of light projected by the lens.
pretty simple physics and math, but maybe you and your friends was out skipping school when your teacher was explaining physics and math...

 

[donny1963]

and here bokeh is about blur in the background, here is an article about it, so i'm not the only one who says this..

The Bokeh Effect: How Sensor Size Affects Background Blur

I gave you a reference to a good article that defines bokeh correctly: Kiev Cameras
Here are definitions:
Oxford dictionary:
bokeh
Pronunciation: /bōˈkā/

noun
Photography
The visual quality of the out-of-focus areas of a photographic image, especially as rendered by a particular lens

Dictionary.com:
noun
a Japanese term for the subjective aesthetic quality of out-of-focus areas of a photographic image.

So now that we know the blog you referenced is also wrong you'd be advised to hold everything else they say suspect as well.

Joe

yeah and that reference says exactly in other terms what i said, lol

WOW!!!!!!!!!!!

 

[robbins.photo]

Ok, so the very first thing I learned about bokeh. You never want to post anything about it to TPF. If you do you'll wind up in a hypertechnical discussion with dozens of posters attempting to one up each other to display their vast technical knowledge. There will corrections posted correcting corrections and it dissolves quickly into a complete cluster.

So, the first rule about bokeh? Don't talk about bokeh.

Sent from my N9518 using Tapatalk

It's not rocket science, it's just simple stuff misunderstood by a vast army of Youtube vloggers and bloggers.

Joe

And yet it generates a massive amount of snark whenever anything gets posted on the subject. Everyone dives for their professor hat and the conversation goes from nasty to nastier, with tons of condescension tossed in for good measure.

So yup, my advice to the op, walk away from this thread and don't post about bokeh in the future.


I suggest you avoid crop factor discussions as well, they seem to have a similar effect

Sent from my N9518 using Tapatalk

 

[donny1963]

Not an error, full frame vs APSC does effect exposure differently using the same situation , or should i say larger sensors have an advantage over smaller sensors with the amount of light, for instance a med format camera requires 28% less light then a full frame camera to get the same exposure with the same situation. same with full frame vs apsc ..

And how exactly does that alter the degree of background blur?

But wait! Before you try and answer that please confirm this: Describe specifically this advantage in amount of light for a FF sensor. Your saying that at same ISO, shutter speed and ambient light with lenses at same AOV and both at f/2.8 the APSC camera will be exposed less than the FF. Yes or no?

Joe

Intuitively, if you put the same lens with the same settings on both cameras, and if the distance from the lens to the sensor is the same in both cases, then the full frame sensor will collect more light because the sensor is larger and therefore covers more of the circle of light projected by the lens.
pretty simple physics and math, but maybe you and your friends was out skipping school when your teacher was explaining physics and math...

yes the same everything try to make the situation exactly the same, but with one sensor larger then the other..

An APS-C sensor is about 24x15mm, while a Full Frame (FF) sensor is 36x24mm. In terms of area, the APS-C sensor is about 360mm^2, and the FF is 864mm^2. Now, calculating the actual area of a sensor that is functional pixels can be rather complex from a real-world standpoint, so we will assumeideal sensors for the time being, wherein the total surface area of the sensor is dedicated to functional pixels, assume that those pixels are used as efficiently as possible, and assume all other factors affecting light (such as focal length, aperture, etc.) are equivalent. Given that, and given that our hypothetical cameras are both 8mp, then its clear that the size of each pixel for the APS-C sensor is smaller than the size of each pixel for the FF sensor. In exact terms:

APS-C:
360mm^2 / 8,000,000px = 0.000045mm^2/px
-> 0.000045 mm^2 * (1000 µm / mm)^2 = 45µm^2 (square microns)
-> sqrt(45µm^2) = 6.7µm

FF:
864mm^2 / 8,000,000px = 0.000108mm^2/px
-> 0.000108 mm^2 * (1000 µm / mm)^2 = 108µm^2 (microns)
-> sqrt(108µm^2) = 10.4µm

In simpler, normalized terms of "pixel size", or the width or height of each pixel (commonly quoted on photo gear web sites), we have:

APS-C Pixel Size = 6.7µm pixel
FF Pixel Size = 10.4µm pixel

In terms of pixel size, a FF 8mp camera has 1.55x larger pixels than an APS-C 8mp camera. A one-dimensional difference in pixel size does not tell the whole story, however. Pixels have two-dimensional area over which they gather light, so taking the difference between the area of each FF pixel vs. each APS-C pixel tells the whole story:

108µm^2 / 45µm^2 = 2.4

An (idealized) FF camera has 2.4x, or about 1 stop worth, the light gathering power of an (idealized) APS-C camera! That is why a larger sensor is more beneficial when shooting in low light...they simply have greater light gathering power over any given timeframe.

In alternative terms, a larger pixel is capable of capturing more photon hits than a smaller pixelin any given timeframe (my meaning of 'sensitivity').

SNow, the example and computations above all assume "idealized" sensors, or sensors that are perfectly efficient. Real-world sensors are not idealized, nor are they as easy to compare in an apples-to-apples fashion. Real-world sensors don't utilize every single pixel etched into their surface at maximum efficiency, more expensive sensors tend to have more advanced "technology" built into them, such as microlenses that help gather even more light, smaller non-functional gaps between each pixel, backlit wiring fabrication that moves column/row activate and read wiring below the photo-sensitive elements (while normal designs leave that wiring above (and interfering with) the photo-sensitive elements), etc. Additionally, full-frame sensors often have higher megapixel counts than smaller sensors, complicating matters even more.

A real-world example of two actual sensors might be to compare the Canon 7D APS-C sensor with the Canon 5D Mark II FF sensor. The 7D sensor is 18mp, while the 5D sensor is 21.1mp. Most sensors are rated in rough megapixels, and usually have a bit more than their marketed number, as many border pixels are used for calibration purposes, obstructed by sensor filter mechanics, etc. So we'll assume that 18mp and 21.1mp are real-world pixel counts. The difference in light-gathering power of these two current and modern sensors is:

7D APS-C: 360mm^2 / 18,000,000px * 1,000,000 = 20µm^2/px
5DMII FF: 864mm^2 / 21,100,000px * 1,000,000 = 40.947 ~= 41µm^2/px

41µm^2 / 20µm^2 = 2.05 ~= 2

The Canon 5D MkII Full-Frame camera has about 2x the light gathering power of the 7D APS-C camera. That would translate into about one stops worth of additional native sensitivity. (In reality, the 5DII and 7D both have a maximum native ISO of 6400, however the 7D is quite a bit noisier than the 5DII at both 3200 and 6400, and only really seems to normalize at about ISO 800.

See: Canon EOS 7D Review) In contrast, an 18mp FF sensor would have about 1.17x the light gathering power of the 21.1mp FF sensor of the 5D MkII, since fewer pixels are spread out over the same (and larger than APS-C) area.