Welcome to our community

Be a part of something great, join today!

Register Log in
  • Hey all, just changed over the backend after 15 years I figured time to give it a bit of an update, its probably gonna be a bit weird for most of you and i am sure there is a few bugs to work out but it should kinda work the same as before... hopefully :)

No crop factor or small crop factor Lens list

Madjid El ayari said:
Hi

I have heard that the tokina 11-16mm and the s35 lens has no crop factor at 4k or a very small one

Question : what are the inexpensive lens like the tokina 11-16 with no or a very small crop factor ? ( considering s35 lens are pl mount expensive lens )
Click to expand...

for the billionth time. Crop factor is a function of sensor size, NOT lens.

I think you're asking what cheap lenses are designed for S35-sized sensors? In canon-mount land those are referred to as APS-C sensors..
Look up just about any sigma, tamron, samyang, canon, etc lenses that are designed for the APS-C sensor, which will come with a canon mount.

There are conversions you can do to those lenses to give them a PL mount (like the tokina-- it's not available in PL mount normally but duclos makes
a conversion).
 
The sensor is what's causing the crop factor, not the lens. So 5k has 1.3x crop factor, 4k has 1.6x and 2k has 2.0x crop factor regardless what lens you have on.

Tokina 11-16mm has equivalent focal length of 17-25mm on 4k. The focal length is all based off of full frame.
 
Madjid El ayari said:
Aps-c or full frame lens are similar when it s written 24mm you have to multiply by 1,6 on a 4k frame =40 mm , you have to multiply by 1,6 to know what is the focal you are using

My question si different : with the tokina 11m equal 11mm on 4k ( i have heard, may be it s not right ! ) , Is there other lens like that ? ( i am not asking for some mathematical physical explaination, so please don t , i am looking for some similar lens for the same price )
Click to expand...

11mm will always be 11mm. The lens does not change. However, if you are asking "will the 11mm on 4k have the same angle of view as an 11mm on a full-frame stills camera?", then the answer is no because your sensor is smaller and is seeing a smaller section of the lens.

I really hate the term "crop factor" as it's only relevant to full frame stills cameras. You have a cinema camera, think in cinema terms.
 
Majid, all lenses are marked with their actual focal length. This does not change depending on sensor size. If it says 11mm, it is 11mm.

When comparing a scene shot with a Tokina 11-16mm on a s35 camera and the same scene shot with a FF35mm camera (36x24 sensor), the field of view on the Tokina would be equivalent to the field of view using a 17-18mm lens on the FF35 camera.
Regardless, if you want to get the same sort of field of view that the 11-16 gives you, you do need to look for lenses in that same focal length range. It won't be marked any differently. There's a 10-20 from Sigma, 10-24 from Nikon, various lenses from Tamron and others.
 
5K vs. 4K vs. FF35 is a whole other ballgame, there. Red's MX sensor in the Epic and Scarlet is larger than s35 when shooting in 5K mode. Not all s35 glass will cover the larger image circle required. FF35 is even larger than 5K.
 
APS-C lens like Tokina 11-16mm get some vignetting at the corners @11mm. But at 12mm vignetting goes away. Otherwise, it works fine.
 
Madjid El ayari said:
Ok so s35 fit the area of the sensor wich record in 4k mode . So does the the angle view change or it is the same at what it is written on the lense . ex: 11mm s35 lens equal 11mm or 17mm at 4k ?
Click to expand...

Yes. S35=4K. The FOV of 11mm at S35/4K is approx 17mm. However...an 11mm is still an 11mm, as everyone says, a thousand times. You may only be seeing a 17mm FOV, but the behavior of the 11mm is still like any 11mm, with that wide-angle distorted barreling. That doesn't change even if you are seeing less of it.

Every focal length has a personality, whether you see more or less of it.
 
D Fuller said:
+1

I really wish the whole idea of "crop factor" would die a quick and merciful death. It is not a very useful way to think about lenses.
Click to expand...

I heartily disagree. Crop factor is actually a VERY meaningful term. It's just not one that people who have ALWAYS shot S35 care about. Otoh, for people who have been switching around from full-frame 35 (like the 5dm2) to aps-c (like 7d) and even micro-4/3, crop factor is a beautifully simple explanation of what happens. The issue here is that many of the new scarlet users COME from the DSLR world, and most of the epic users come from the cine world.. and voila, conflict...

Here's the deal. Focal length is really just a function of the lens. It tells us where the nodal point is relative to the film plane. An 11mm lens is an 11mm lens on EVERY sensor/film type ever. However. Many people who have shot FF35 most of their lives also know that 11mm is this 'kind of super-wide' look. This can be correctly described with the Field of View. When they take this 11mm lens and stick it on a 16mm sensor, they get really unhappy that the image looks NOTHING like what they were expecting. So to make THEIR lives easier, we use a crop-factor multiplier. We tell people that this camera has a crop factor of 3x. And instantly the photographer knows that this lens will look more like a 33mm lens on this camera (or alternatively, if he wants to re-create the look he got with the 11mm lens, he needs to find a 4mm lens). He doesn't need any lookup tables or charts using the old FoV vs the new one, or anything.

So it *is* a very useful number. and for those coming from the DSLR land it is good to know that the scarlet at 4K is about the same as the canon 7D/T3i, with a 1.6x crop factor. And that at 3K it's close to micro-4/3's crop factor of 2x. None of this is 'wrong', just could be described better using FoV. Unfortunately, due to the fact that some scarlet users come from cine-land, they strongly (and also correctly) assert that there *IS NO* crop factor on the scarlet... because they are comparing it to S35 film -- which I'm fairly certain anyone who comes from cine-land doesn't really care for crop factors -- they already know what lenses do on different films...

The real problem is that so many people now associate crop-factor with EF-S lenses, that they get confused not realizing that it's not the lens that is causing the crop factor, but the fact that the sensor/film is not the same size as the FF35 that they were used to in photography, and so we get questions like "what is the crop factor of lens XYZ on the scarlet".. The answer that they are looking for, irrelevant of any lens, is almost always 1.6x...

(or rant done -- sorry.. it feels like I'm just flaming for no good reason... has anyone considered making a wiki-faq page? this question comes up a LOT)
 
At this point, I wish the 5d had never happened. We never spoke of crop factor between 35mm and 16mm. I shot a lot of 16 with 35 lenses. You just adjust to what you expect to see with a particular lens.
Picture this:
You are standing a few feet from a windowThat's your focal lenght. Now, in front of you you are holding a large piece of cardboard with a rectangular hole in it. That's your sensor size. Now change the cardboard with one with a smaller hole in it. You see less of the window, but it's still the same focal length. To see the same amount of the window, you have to move back, changing your focal lengh, to get the same field of view.
so a 25mm lens will be the same wether 35mm, 16mm, 2/3's 4/3's and so one. It's just a smaller "hole"
Die crop factor, die! And please don't use the 5d as a measure stick for cinematography! That's like using my daughters Vtech "My First abc learning laptop" as a standard for computing...
 
Yoav Yerushalmi said:
I heartily disagree. Crop factor is actually a VERY meaningful term. It's just not one that people who have ALWAYS shot S35 care about. Otoh, for people who have been switching around from full-frame 35 (like the 5dm2) to aps-c (like 7d) and even micro-4/3, crop factor is a beautifully simple explanation of what happens. The issue here is that many of the new scarlet users COME from the DSLR world, and most of the epic users come from the cine world.. and voila, conflict...

Here's the deal. Focal length is really just a function of the lens. It tells us where the nodal point is relative to the film plane. An 11mm lens is an 11mm lens on EVERY sensor/film type ever. However. Many people who have shot FF35 most of their lives also know that 11mm is this 'kind of super-wide' look. This can be correctly described with the Field of View. When they take this 11mm lens and stick it on a 16mm sensor, they get really unhappy that the image looks NOTHING like what they were expecting. So to make THEIR lives easier, we use a crop-factor multiplier. We tell people that this camera has a crop factor of 3x. And instantly the photographer knows that this lens will look more like a 33mm lens on this camera (or alternatively, if he wants to re-create the look he got with the 11mm lens, he needs to find a 4mm lens). He doesn't need any lookup tables or charts using the old FoV vs the new one, or anything.

So it *is* a very useful number. and for those coming from the DSLR land it is good to know that the scarlet at 4K is about the same as the canon 7D/T3i, with a 1.6x crop factor. And that at 3K it's close to micro-4/3's crop factor of 2x. None of this is 'wrong', just could be described better using FoV. Unfortunately, due to the fact that some scarlet users come from cine-land, they strongly (and also correctly) assert that there *IS NO* crop factor on the scarlet... because they are comparing it to S35 film -- which I'm fairly certain anyone who comes from cine-land doesn't really care for crop factors -- they already know what lenses do on different films...

The real problem is that so many people now associate crop-factor with EF-S lenses, that they get confused not realizing that it's not the lens that is causing the crop factor, but the fact that the sensor/film is not the same size as the FF35 that they were used to in photography, and so we get questions like "what is the crop factor of lens XYZ on the scarlet".. The answer that they are looking for, irrelevant of any lens, is almost always 1.6x...

(or rant done -- sorry.. it feels like I'm just flaming for no good reason... has anyone considered making a wiki-faq page? this question comes up a LOT)
Click to expand...

All this "explanation" kind of proves my point, don't you think?
 
D Fuller said:
All this "explanation" kind of proves my point, don't you think?
Click to expand...

lol.. yes.. but I think you missed the point I was really trying to make (it *was* a long rant).

Many scarlet shooters today are fairly familiar with the behavior of a lens on FF35 (or APS-C). Computing what a lens will look like on the scarlet is *trivial* using the crop-factor (multiply by around 1.5 and voila!).

If otoh, we stuck to using FoV computations... well.. my 50mm lens (the normal look I'm used to) has a FoV of around..ermm 39 degrees. Ok, so now I want to get a 39 degree look using the scarlet at 3k.. what simple math gets me there? (I'll point out that FoV computations are based on trig functions.... and most people here can't compute inverse arctan in their heads..)...

So anyways. What I was trying to say is that crop factor is a very useful metric in understanding what lens you want to use, especially when starting out. Over time you get more accustomed to the behavior of the lens on your current sensor, and then stop caring as much about focal length crop factors.... (and that's where many of the cine folks are right now.. they get grumpy because they already KNOW that the lens they wanted was a 30mm, and can't understand why people don't just 'get it').

In the meanwhile, it's not that much work to tell someone 'it's 1.6x'. But then we get people who don't understand the reasoning behind this, and ask questions like 'but what about on THIS 11mm lens...?'.

fwiw, a similar pet peeve of mine is DoF and lenses. People assuming that low number focal length lenses all have deep focus and vice-versa... totally missing that DoF relates to aperture, sensor size/resolution, AND focal length. I'd like to believe cinematographers understand the basics of how lenses work, but one of the plusses/minuses of the new DSLR video movement is that there are a lot more cinematographers out there who just picked up a camera and are learning as they go...
 
Yoav Yerushalmi said:
one of the pluses/minuses of the new DSLR video movement is that there are a lot more cinematographers out there who just picked up a camera and are learning as they go...
Click to expand...

I love your passion, but this is one of my pet peeves. That we use these words so indiscriminately. Cinematographer, Director, artist even. Maybe cuz I'm in New York, and I hear these words sometimes too, it really throws me off. A guy who is learning as they go is not, in my book a cinematographer. Shooter? Yes. Talented? Most likely, he's working, and he/she's passionate, so that's half the battle. But cinematographer? I revere the word (and I'm just a hack producer, and wannabe director who hates even using that latter word, because I haven't really earned it, at least not to my estimation yet). Cinematographer to me is approaching master level. They've learned so much, and even though they are always learning, what's left are the small tiny things that surprise them every day. But not the big things. They've mastered all the big and medium things, made lots of mistakes along the way, and are now cinematographers. But if you are picking up a camera, a DSLR, or even a RED, and are learning as you go, then you are passionate. But that is not the same as being a technical master, someone a crew looks to for guidance, speed and reliability, a master who can paint a picture, with lights, lenses and a camera.

I love the word cinematographer, I aspire to know as much as them, and understand their world. But its a word dripping in Hollywood history, and I think it needs to be treated carefully. It should be earned, not stepped, or fallen into.
 
Yoav Yerushalmi said:
lol.. yes.. but I think you missed the point I was really trying to make (it *was* a long rant).

Many scarlet shooters today are fairly familiar with the behavior of a lens on FF35 (or APS-C). Computing what a lens will look like on the scarlet is *trivial* using the crop-factor (multiply by around 1.5 and voila!).

If otoh, we stuck to using FoV computations... well.. my 50mm lens (the normal look I'm used to) has a FoV of around..ermm 39 degrees. Ok, so now I want to get a 39 degree look using the scarlet at 3k.. what simple math gets me there? (I'll point out that FoV computations are based on trig functions.... and most people here can't compute inverse arctan in their heads..)...

So anyways. What I was trying to say is that crop factor is a very useful metric in understanding what lens you want to use, especially when starting out. Over time you get more accustomed to the behavior of the lens on your current sensor, and then stop caring as much about focal length crop factors.... (and that's where many of the cine folks are right now.. they get grumpy because they already KNOW that the lens they wanted was a 30mm, and can't understand why people don't just 'get it').

In the meanwhile, it's not that much work to tell someone 'it's 1.6x'. But then we get people who don't understand the reasoning behind this, and ask questions like 'but what about on THIS 11mm lens...?'.

fwiw, a similar pet peeve of mine is DoF and lenses. People assuming that low number focal length lenses all have deep focus and vice-versa... totally missing that DoF relates to aperture, sensor size/resolution, AND focal length. I'd like to believe cinematographers understand the basics of how lenses work, but one of the plusses/minuses of the new DSLR video movement is that there are a lot more cinematographers out there who just picked up a camera and are learning as they go...
Click to expand...


Oh, I understood exactly the point you were trying to make. I just disagree with it. I didn't say it was not a meaningful term, I said it was not a very useful way to think about lenses.

"Crop factor" is not a lens concept at all. It's a film-size/sensor-size concept, and has nothing to do with lenses. Yes, it does change the angle of view, but not by changing anything about the lens. You put the same lens on two different cameras, and the lens doesn't change its behavior, it's the camera that changes. Most people don't seem to believe that. "Crop factors" seem to cause more confusion than any other lens-related issue. (Just do a google search on this site and read the results. It's not pretty.) It very often leads to misunderstandings like the OP in this thread.

This is what I mean by it not being a very useful way to think about lenses. It leads people to think they understand something about lenses when they do not. And it leads them to apply concepts to lenses that have nothing to do with lenses. I'm not grumpy because people "don't just 'get it'". I'm grumpy because this concept leads people to misunderstand how lenses work in some very fundamental ways, and it hinders their ability to learn things they need to learn if they are going to become cinematographers. Why is it that a "normal" lens on a medium format camera draws an image so much differently than a "normal" lens on an APS-c camera? The "crop factor" has been equalized, but the lenses are very different.

Lenses have complex rendering characteristics that go way beyond their angle of view. You learn about that by looking through lenses. A lot of lenses. But to think that you can translate that experience by simple math is just wrong. In the first place, lenses aren't manufactured that way. If you want the equivalent angle of view of a 50mm on a full-frame 35mm still camera, using your 1.6 factor, you need a 31.25mm lens. Where are you going to find one of those? And when you find one, it won't look like the 50mm you remember in some important ways. It'll have more DoF at a given f-stop. It'll have different flare characteristics, and so on. Then the "crop factor" idea applies a level of precision to a calculation that is beyond most of its users ability to truly understand. Is it really necessary to calculate using 1.6? Why wouldn't 1.5 do? (The math's easier.) You're not going to find a a 33.33mm lens either. It's a lot of math, and not enough looking through lenses. And unless you are doing VFX, that level of precision is not important. It's better to put a lens on and look through it. And if you don't think it works, change it. Or change where you're standing.

If I know that 35mm is about a "normal" lens on an APS-c sensor, everything else flows from that (unless I'm doing a very technical shot where precise angles are truly important). And this is true for 16mm or medium-format as well.

FWIW, I don't feel this way because I've always shot S35. I've worked in 8mm, Super-8mm, 16mm, Super-16mm, 35mm, Super-35mm, 35mm full frame still, APS-c, a 645, 6x6, 5x7, and 8x10, and more video cameras than I can remember right now. I feel this way because I love lenses and I'm tired of seeing people confused by this concept.
 
It's not that the crop factor concept is not useful, it's just that it is a crutch and not particularly necessary if you actually understand the relationship between lens, sensor, and image properties. Unfortunately because crop factor sounds so simple, people who do not understand optics gravitate toward it but it is not so useful and even confusing if you do not already understand how precisely it relates to the optical relationships it is intended to simplify.

I am happy to use "crop factors" when moving between imager formats or using optical extenders/reducers etc, but unless you are doing that there is really no need for them, and it seems like a lot of people do not understand that. People who aren't sure what they mean probably would be better off learning other optical concepts first before trying to overuse and misuse crop factors. Why do we even call them crop factors? They are also DOF factors, aren't they?
 
D Fuller said:
I feel this way because I love lenses and I'm tired of seeing people confused by this concept.
Click to expand...

I love this quote, and your entire post. My greatest pet peeve with crop factors is when people confuse behavior with FOV. I've had the following happen multiple times on DSLR shoots: "ok, put the 50 1.4 on the 7D, and the 85 1.4 on the 5D, they'll look the same".

Um, no they wont. The FOV will be similar. But they will "feel" different. A 50 is a 50 is a 50. An 85 is an 85 is an 85. They will both be shallow, but the 85 1.4, by being that much more tele and portrait than a 50, will have a more bloomed and mushy bokeh. It will look different. Even if the FOV is the same.

And I say that because I love how an 85 looks and feels. I adore how a 135 looks and feels. I'm also a big fan of how a 35mm feels. These traits won't change even if the sensor size does.

Though, I have to admit, what I'm about to say does punch a whole in this theory. I think the above holds true for lenses at 50mm and above that go tele. But I was on a shoot several weeks back where we used my 35 1.4 on a 5D, and I was blown away by how distorted and wide angle it felt. Obviously, the FOV was more like a 21mm on a 7D. That was a huge learning curve for me, seeing how a wide FOV could change a lenses personality. Suddenly, the 35 1.4 (which normally is a portrait 2shot for me), was a wide angle comedy friendly lens on the 5D. Its personality had changed a bit. But, most of its other characteristics remained the same however.

I think I'm making this all just more complicated. But my takeaway, or what I'd like to add, is lenses have personalities, have character. Learn what each one does, and worry less about how little or much you are going to see of it.
 
You must log in or register to reply here.
Back
Top