Sunday, May 1, 2016

Lens vs Camera

Today at one of a famous Facebook Photography page, i came across a very interesting argument. I was saying ….. Bodies comes and goes …. Lenses remains forever.

And then one young talent jumped-in with a counter argument " Balance is a Key. No point of getting very expensive lens when your body cannot utilise it". 

And i was like …. :O …. Really !!!!! … Am i missing something here? What lens has to do with the body any ways, even technically speaking? …. Then i asked the gentleman " What body has to go (technically speaking) by utilizing the lens? " ….. and to my surprise the gentleman replied "For Instance ISO Performance. You can utilise higher ISO at time". 

That reply was too much for me to digest. I am not going to lie but i was feeling sorry for that gentleman. It was not his fault for what ever he was saying to be honest. Why? Because in our country people take photography as a FASHION rather then as a field of interest to learn it to the core. And when u do fashion ….. You just follow the trend rather then first read it …. understands it …. and then apply it. In our country these days, every one is either want to Actor … or model …. or Director. And if they not able to make any of it, then becoming Photography is their last and easy option to go with. Since the world is becoming digital, things are becoming to easy and accessible for all. Same applied for photography. Make no mistake about it but respect all professional photographers who running their kitchen and paying the bills .... its not easy to make both end meet using a Camera. Trust me on that.

Since digital took over the film photography, a wise man said a beautiful line …. "Digital makes you lazy" ….. This is one of the main reason you often see many people carrying digital camera these days. Many people want to be Professional Photographer without realizing the fact that this field will suite them or not .... How to break-in into the market. How to advertise your work (not talking about making Facebook Page) etc etc.

Coming back the main topic which is what lens has to do with camera bodies which are better capable of handling higher ISO values. By the way …. just like to share a key point that ISO has nothing to do with the Exposure Triangle. Its just a applied gain just like an audio amplifier where you pumping up the volume as per your need. Same applies for the ISO value of the machine. Every machine sensor got a basic ISO value which you can "manipulate" later either from the camera body or in the post processing to get your desire results. We will have separate blog on that later in future. 

So i was saying about lens role with machine and their ISO capability …. The feedback that i received was "An expensive lens makes a hell lot of difference when they used over a crop body like 70D vs full frame 1Dx". Now this feedback made me start thinking on logical and physical basis what really lens performance has to do with a Crop Body (CB) vs a Full Frame (FF). And if you have read up on you field of interest,  it will not take much of your time to get the answer which is "NONE" when it comes to ISO performance of the body. Lens has nothing to with ISO which i will try to explain in simple words below. But when you compare a 70D vs 1Dx .... there is not major difference among the machines other then the following 

1- ISO performance.
2- Higher FPS
3- AF options and AF speed.  
4- Mega pixels count (which is least relevant) 

Now lets see what ISO has to do with the lens here. Imagine you have Tamron 70-200mm f/2.8 which is a good sharp lens at the center (marked green below) but not towards the edges of the lens. 


Now you have used this lens on a FF body (say Canon 1Dx or Nikon D5) and the expected coverage is going to be like this. 

The above image shows a considerable central area of FF sensor that is covered by the FF lens which is mostly sharp and marked in green (also known as SWEET SPOT). Now i start using this lens on 1Dx or D5 at ISO 100 and then i started increasing the ISO all the way to their top values which is over 400,000 for 1Dx and 3.2 Million ISO for D5. After taking few photos now i decided to switch from FF to CB which is Canon 70D or Nikon D7200 and used the same lens. Lets what happens next.

If you look at the above image it is clear that most of the "Sweet Spot" of the FF lens is covering the CB sensor which is marked in RED of the CB 70D or D7200. So yes …. that's the ONLY ADVANTAGE that i see of using a FF lens on a CB. Now many will jump from the seat and start thinking that i missed the " 1.5/1.6 multiplication zoom factors" here. No i am not forgetting anything. First of all it is NOT ZOOM. That focal length multiplication factor is just "Angle of interception/Field of view". Depth of Field will remain the same if we only change the lens, do not change the aperture and shoot from the same distance. Just like you switch the camera body from D750 to D7200 over a fixed tripod. 

Hay ….. wait a minute ….. where is the ISO thing in this whole conversation and explanation? What lens was doing here when i was changing the ISO from ISO 100 —> 400,000/ 3.2 Million followed by changing the bodies? Is there any "technical attribute" lens is adding to the camera body or in the final image? Let find out. 

Before we see what lens will do with camera body ISO …. we need to see what lens is capable to do and what attributes of the lenses are out there to play with. Lens making is an art. It not easy. A same company some time making a superb lens at one particular focal length but they are unable to replicate the same level of performance & perfection on some other focal length  or making zoom lens. For example, Carl Zeiss is world famous in prime lenses. Their Otus line is world class but their wide angle lenses sucks big …. Yes i am talking about 15mm & 21mm. They are not good in over all performance like their other primes at higher focal length …. not believing me …. google for it and you will get the result. Thats shows the weak point of Carl Zeiss that they are not good in wide angle lenses. 

On the same note ….. Nikon and Canon made whole range of 50 & 85mm lens. But their 60mm lens is not that good like their 50/85mm. Again Nikon and Canon made some excellent Zoom lenses. But Nikon 24-120mm f/4G is not performing like 24-70mm f/2.8G. Same goes for Canon 24-105mm f/4L lens vs 24-70mm f/2.8 lens II USM L lens. And at the same time it is also strange thing to notice that it is not mandatory that a cheap lens performance is lagging behind in compared to any expensive lens. For example Nikon 18-35mm f/3.5-4.5 G is one sharp lens and optically equal in quality with its expensive sibling 16-35mm f/4G VR which is double in price. Same goes for Nikon 35mm f/1.8G DX lens which is only $200 with Auto Focus and its one hell of a sharp lens. So yes, Lens making is an art. 

So what are the lens attributes in general that we know, 

1- Bokeh (most commonly known) 
2- Sharpness
3- Focal Length
4- Offered Aperture

I guess yes …. that's the common known attributes mentioned above. Now following are the addition attributes which many does not know or don't even consider. We all have to include these attributes next time when you buy any lens.

5- Acutance
6- Resolution
7- Rendered depth
8- Perceived depth
9- Micro Contrast (for black and white editing) 
10- Contrast
11- Colour Saturation
12- Meshing 
13- Weight

All above define attributes are happening inside the lens …. or shall i say lens does these attributes what ever makes sense to you. When light enters into the lens from the front element, it get "processed" and WELL DONE by the different glass elements into it and then the processed light get out from the rear glass element of the lens and fall over the sensor. Many fellow photographers doesn't know the fact that the more glass element inside the lens, the more images quality is going to be destroyed. The less glass elements inside the lens produces far better results. We will have a separate blog on it later in future. 

So after light enters and get process by the lens regardless it was a day time or night time ….. lens treating the light the same based on the above mentioned attributes and then throw it over the sensor of the camera body. Now it doesn't matter if the body is 70D or 1Dx …. lens is already done its job ..... Finish ..... Khallas ..... Done. Now its camera body job to process it as per dialed value of "Aperture - Shutter Speed (which is already happened inside the lens) " …. and ISO.

Mind you …. Camera body only add dialed ISO value to the "processed light" which is coming from the lens and then mix it into the blender of the "18% Grey" and then dumped the result on the SD/CF card for your view. It doesn't matter at all if the body is 70D …5Dmk3 … 1dx …. 1200D …. D5 …. D810 ….. D750 …. D3 …. or D3300 ….. Shooting at different ISO's values …… they all behaves the same. .....

Receive light from the lens --> process it as per ISO --> Throw it on the SD/CF Card --> Repeat

No camera body in the world has anything to do with the lens. If lens with aperture f/2.8 is dialed to shoot at f/9 …. it will stopping the light by f/9 regardless whatever body is going to be attached to it shooting at what ever ISO. Camera bodies just processes the light coming from the lens which passed from the f/9 aperture. What ever they will receive  …. they just going to process it …. Simple.

I have seen canon users using Nikon lenses for the ultra wide angle shots using special adapter's ….. that point is clear cut proof that body has nothing to do with the lens. Both are doing their own job independently. 

As i explained in detail what happening between the lens and the camera body ….. does any one still have this confusion Lens has anything to do with the camera body ?

Thanks for stopping by and reading this blog. You all have a great day ahead.



  1. intellectual photographer !!
    u knw every detail (Y)
    good to have u on that famous photography group on fb :D

    1. Thanks for the kind words ..... Here to support :)

  2. Cleared my confusion about using FX lens on DX body.