The most confusing thing for a new shooter…

[OldClicker]

I’ve been at this for about a year and a half and have learned a lot (and learned I still know little) from the forums – especially PR when it comes to image quality. Thanks all.

Maybe it’s just me, but there is one concept that is often presented to the new photographer that I think does far more harm than good. Please never again confuse a new guy with the concept of equivalent focal length and all the trick numbers and fudge factors that go with it. This was all terribly confusing until I figured out that nothing changes with sensor size but the Field of View (FoV) – what I see in the viewfinder and on the image. I don’t have to remember that my 16-80mm lens is really a 24-120mm lens, that the DoF of my 27mm f/2.2 is really 40mm f/3.4, that I can’t hand hold my 210mm at slower than 1/315 second shutter speed, etc., etc. - and all of these EQUIVILENT TO SOME 35MM SIZE THAT I’VE NEVER EVEN SERIOUSLY USED.

So, the next time a noob asks why his close-ups are so much blurrier with his new DSLR than they were with his old P&S, just tell him it’s because what he sees in the viewfinder/LCD is bigger so he moved closer and DoF is a function of aperture and distance. Teach him photography, not number tricks.

Thanks for listening,
TF

[Frog]

Good point. For the numbers oriented mind, its fine, but for those that don't live by them, we only want to know what we need to do to get those shots.
I know the math for sensor size but I didn't even know it affected aperture. As for whether I can't get a good shot with a certain shutter speed and zoom ratio...well if I can't, I use a tripod. The reasons these things happen are good to know but don't really apply as to how to get the shot.

[poker]

I agree that explaining crop factors are almost pointless. I think it was only relevant for those moving from film SLRs to DSLRs. Less photographers now will have a full frame camera so discussing crop factors is unnecessary. IMO

I had a hard time learning and have a hard time explaining:

"A larger aperture give you a shallow depth of field. Oh, and a larger aperture is a lower number."

I'm always learning.

[BlueRob]

I see you point and share it OC but we can´t deny that knowledge is power and to really understand the Why´s and How´s at one point you will start to play with the numbers and understand them. I mean if a NewB wants to go from a P&S to a SLR a lot of "technical" aspects need to be "discovered" and understood...if you don´t want to mess with "technical terms" well...go back to a P&S or keep the dial in the AUTO.

Whit this I don´t mean you have to learn these things by heart but at least have a good general idea of where the numbers came from and what do they represent, becoming familiar with this type of things takes time and curiosity.

[apass]

Whit this I don´t mean you have to learn these things by heart but at least have a good general idea of where the numbers came from and what do they represent, becoming familiar with this type of things takes time and curiosity.

Ohhh yes...good points.

[OldClicker]

I see you point and share it OC but we can´t deny that knowledge is power and to really understand the Why´s and How´s at one point you will start to play with the numbers and understand them. I mean if a NewB wants to go from a P&S to a SLR a lot of "technical" aspects need to be "discovered" and understood...if you don´t want to mess with "technical terms" well...go back to a P&S or keep the dial in the AUTO.

Whit this I don´t mean you have to learn these things by heart but at least have a good general idea of where the numbers came from and what do they represent, becoming familiar with this type of things takes time and curiosity.

I think you have exactly backwards. These tricks delay the learning of what is really happening. The numbers aren't real. Teach them (us/me) aperture, shutter speed and ISO, not fudge factors and especially not fudge factor from a format they have never used. - TF

[freygr]

DOF has to do with the angle of view, and aperture. The focal length of the lens and distance give you the depth of field, but for the same angle of view of the subject with any lens which can cover the film/sensor the DOF will be the same! But the distances will vary greatly. Unluckily I did not save the site which mathematical proved it and had the examples also.

[BlueRob]

I think you have exactly backwards. These tricks delay the learning of what is really happening. The numbers aren't real. Teach them (us/me) aperture, shutter speed and ISO, not fudge factors and especially not fudge factor from a format they have never used. - TF

Unless the learning process you talk about is completely different as I understand it, it is inevitable to deal with the numbers and terms related in one point in time. Is like trying to understand algebra and don´t have a clue what the numbers represent and how to deal with them. You have to understand the basic concepts and then develop the rest of the stuff given that base point.
The ISO Aperture etc, that you mention are linked or related to the numbers...either in a 35mm camera or its equivalents. IMO you have to know them....again not by heart but understand their roots and how they relate to the other settings or factors involved.

If you "learn" without these bases your understanding and knowledge is non-existent and you are reallying on an empiric method, that I don´t doubt it works but is founded on thin air if you ask me. Setting a camera with an "empiric" method becomes and almost endless trial and error process which takes your attention out of the viewfinder where it should be. If you know the plain principals I´m sure you will be a more "complete" photographer.
I hope that in the near future I can master these simple principals and thus keep my attention on the "artistic" side of photography dealing more with composition , light, etc and less time time tweaking the camera to nail what I want to capture how I want to capture it. Just my point of the view....

[OldClicker]

Unless the learning process you talk about is completely different as I understand it, it is inevitable to deal with the numbers and terms related in one point in time. Is like trying to understand algebra and don´t have a clue what the numbers represent and how to deal with them. You have to understand the basic concepts and then develop the rest of the stuff given that base point.
The ISO Aperture etc, that you mention are linked or related to the numbers...either in a 35mm camera or its equivalents. IMO you have to know them....again not by heart but understand their roots and how they relate to the other settings or factors involved.

If you "learn" without these bases your understanding and knowledge is non-existent and you are reallying on an empiric method, that I don´t doubt it works but is founded on thin air if you ask me. Setting a camera with an "empiric" method becomes and almost endless trial and error process which takes your attention out of the viewfinder where it should be. If you know the plain principals I´m sure you will be a more "complete" photographer.
I hope that in the near future I can master these simple principals and thus keep my attention on the "artistic" side of photography dealing more with composition , light, etc and less time time tweaking the camera to nail what I want to capture how I want to capture it. Just my point of the view....

Nope, in my opinion you still have it wrong. The 'equivalents' are like fudge factors or little rhymes that you memorize so that you don't have to learn the algebra. There are numbers with aperture, DoF, etc. - real ones - and those are the ones you have to understand. – TF

[BlueRob]

Nope, in my opinion you still have it wrong. The 'equivalents' are like fudge factors or little rhymes that you memorize so that you don't have to learn the algebra. There are numbers with aperture, DoF, etc. - real ones - and those are the ones you have to understand. – TF

Sorry to say this OC, but is not fair to classify something as WRONG or RIGHT in this matter. I consider it as a different approach....just because I have a different point of view does this make it WRONG? sorry but do no think so.

We can´t deny that digital equipment is based usually on the 35mm..if you or others find the numbers useful or not that is another ball, but they are there, and lenses and camera specs are based on those numbers. Some people will find it useful to do the math others don´t....and that does not mean they are wrong.

What happens when you migrate to a different sensor? You will be wondering why the parameters that worked best for you with a given lens suddenly gives you different results...."fudge factors" not for me....they are specs and in some point in time you will use them either as an 35 equivalent or the other way around.

[OldClicker]

"Sorry to say this OC, but is not fair to classify something as WRONG or RIGHT in this matter. I consider it as a different approach....just because I have a different point of view does this make it WRONG? sorry but do no think so."

I don't really understand what you are saying here. I never said right or wrong (even in small letters). I also consider teaching equivalent numbers as a merely different approach, but one I believe only delays learning the basics of photography. It's like memorizing, "righty - tighty; lefty-loosey" to figure out how to tighten or loosen a nut or bolt. That's fine if you loosen a bolt now and then, but if you want to become a mechanic you are better off learning early what is really going on.

"We can´t deny that digital equipment is based usually on the 35mm..if you or others find the numbers useful or not that is another ball, but they are there, and lenses and camera specs are based on those numbers. Some people will find it useful to do the math others don´t....and that does not mean they are wrong."

Nothing about a lens is based on a 35mm camera (see how it confuses?). A lens is what it is no matter what you mount it on. And what on a P&S is based on a 35mm body?

"What happens when you migrate to a different sensor? You will be wondering why the parameters that worked best for you with a given lens suddenly gives you different results...."fudge factors" not for me....they are specs and in some point in time you will use them either as an 35 equivalent or the other way around."

Why would I find 35mm fudge factors useful when migrating from my P&S to my APS-C? And I think that the changes I would experience are better explained with basic photography - distance, focal length, aperture, etc. If I were to win the lottery and pick up an FF, I would have no trouble understanding that what I used to see is just the center portion of what I see now. Everything else just falls in place – the changes are no longer mysterious.

I'm not proclaiming any new religion or divine inspiration here, just that those who come to this forum to ask questions usually have the goal of becoming serious photographers. I believe that we would serve them better by advising them to learn photography, not tricks.

TF

[BlueRob]

"Sorry to say this OC, but is not fair to classify something as WRONG or RIGHT in this matter. I consider it as a different approach....just because I have a different point of view does this make it WRONG? sorry but do no think so."

I don't really understand what you are saying here. I never said right or wrong (even in small letters). I also consider teaching equivalent numbers as a merely different approach, but one I believe only delays learning the basics of photography. It's like memorizing, "righty - tighty; lefty-loosey" to figure out how to tighten or loosen a nut or bolt. That's fine if you loosen a bolt now and then, but if you want to become a mechanic you are better off learning early what is really going on.

"We can´t deny that digital equipment is based usually on the 35mm..if you or others find the numbers useful or not that is another ball, but they are there, and lenses and camera specs are based on those numbers. Some people will find it useful to do the math others don´t....and that does not mean they are wrong."

Nothing about a lens is based on a 35mm camera (see how it confuses?). A lens is what it is no matter what you mount it on. And what on a P&S is based on a 35mm body?

"What happens when you migrate to a different sensor? You will be wondering why the parameters that worked best for you with a given lens suddenly gives you different results...."fudge factors" not for me....they are specs and in some point in time you will use them either as an 35 equivalent or the other way around."

Why would I find 35mm fudge factors useful when migrating from my P&S to my APS-C? And I think that the changes I would experience are better explained with basic photography - distance, focal length, aperture, etc. If I were to win the lottery and pick up an FF, I would have no trouble understanding that what I used to see is just the center portion of what I see now. Everything else just falls in place – the changes are no longer mysterious.

I'm not proclaiming any new religion or divine inspiration here, just that those who come to this forum to ask questions usually have the goal of becoming serious photographers. I believe that we would serve them better by advising them to learn photography, not tricks.

TF

Nope, in my opinion you still have it wrong.

As I stated before OC I see your point and I agree that these numbers do confuse new ones, and that there are other aspects more important to learn, aspects that deal greater influence in the shots such as understanding the ISO, f´s, etc.

I´m not saying that these numbers (fudge factors) should be an introductory lecture to new guys trying to understand photography...as a matter of fact the few threads where I get the chance to answer the "basics" of photography I have never mention them...with that being said I still think that in some point of the learning curve, one has to be aware about these numbers...either if you use them or not...that it is all I´m saying...I dont preach either that these numbers rule good photography but if you are aware they they exist and know how they interact with the rest of the factors, you are a....how to say it...less ignorant... or a more acquainted photographer.

Don´t you think that the more knowledge the better?
For me it is much more confusing the lack of knowledge than the excess of it....most of the knowledge we gather through our short existence in this earth does not apply in a daily basis.

[BlueRob]

By the way...which thread(s) detonated this subject?

[OldClicker]

By the way...which thread(s) detonated this subject?

No thread(s) detonated anything. Just a year and a half of watching confusion. - TF

[OldClicker]

As I stated before OC I see your point and I agree that these numbers do confuse new ones, and that there are other aspects more important to learn, aspects that deal greater influence in the shots such as understanding the ISO, f´s, etc.

I´m not saying that these numbers (fudge factors) should be an introductory lecture to new guys trying to understand photography...as a matter of fact the few threads where I get the chance to answer the "basics" of photography I have never mention them...with that being said I still think that in some point of the learning curve, one has to be aware about these numbers...either if you use them or not...that it is all I´m saying...I dont preach either that these numbers rule good photography but if you are aware they they exist and know how they interact with the rest of the factors, you are a....how to say it...less ignorant... or a more acquainted photographer.

Don´t you think that the more knowledge the better?
For me it is much more confusing the lack of knowledge than the excess of it....most of the knowledge we gather through our short existence in this earth does not apply in a daily basis.

The only reason I can see for understanding that 'the DoF of my 27mm f/2.2 is really 40mm f/3.4' is to explain what is really going on when the noob asks for it to be explained. - TF

[EOSThree]

I have been following this thread for several days now. I see valid points. Here's my $ .02. OK I am let's say I am with you on this, OC. Focal length is just that, it's a number. Now lets get out my P&S camera...oops the numbers published are an equivalent focal length. Equivalent to 35mm.

Canon Powershot G11 28-140mm (actually 6.5-30.5)
Olympus FE 360 36-108mm (actually 6.3-18.9)
Kodak Easy Share C1013 34-102mm (stated on the lens as "equivalent")
Nikon Coolpix L18 34-102mm (actually 5.7-17.1)

There are many more examples of this. All of these numbers are based on 35mm. 35mm film was the standard for more than just SLRs, point and shoots, rangefinders, etc. all used 35mm film. It's what most people are familiar with. And truth is, it is a number, but for some reason the manufacturers feel the need to give an equivalent number for their P&S cameras. When the APS-C cameras came out the lenses' focal lengths were also given in 35mm terms.

But if someone asks me what lens would be good, unless I have equivalent numbers, I would have no idea what a 5.7mm lens is. My initial reaction would be to say, a what? that's got to be a mis-print, nothing's that wide. We need an anchor, something to base our thoughts on. 35mm film standards are that anchor.

So for someone selling a camera or someone buying a camera some kind of reference is necessary. What constitutes a wide angle lens? 50mm on a 645, 17mm on a DSLR, unless it's a full frame DSLR then it's around 28mm, then on a point and shoot camera it's around 5 to 6mm. Maybe confusing, but necessary to have a base line.

Sure I agree, focal length is solely a function of the actual length of a lens, but from there everything depends on the size of the film to determine what the actual field of view is. And determining the field of view has everything to do with the function of the lens on the body.

[OldClicker]

I have been following this thread for several days now. I see valid points. Here's my $ .02. OK I am let's say I am with you on this, OC. Focal length is just that, it's a number. Now lets get out my P&S camera...oops the numbers published are an equivalent focal length. Equivalent to 35mm.

Canon Powershot G11 28-140mm (actually 6.5-30.5)
Olympus FE 360 36-108mm (actually 6.3-18.9)
Kodak Easy Share C1013 34-102mm (stated on the lens as "equivalent")
Nikon Coolpix L18 34-102mm (actually 5.7-17.1)

There are many more examples of this. All of these numbers are based on 35mm. 35mm film was the standard for more than just SLRs, most point and shoots, rangefinders, SLRs, etc. And truth is, it is a number, but for some reason the manufacturers feel the need to give an equivalent number for their P&S cameras. When the APS-C camera bodies came out the lenses were given in 35mm terms I mean if someone told most people this camera has a 5.7mm to 17.1mm lens most wouldn't care.

But if someone asks me what lens would be good, unless I have equivalent numbers, I would have no idea what a 5.7mm lens is. My initial reaction would be to say, a what? that's got to be a mis-print, nothing's that wide.

So for someone selling a camera or someone buying a camera some kind of reference is necessary. What constitutes a wide angle lens? 50mm on a 645, 17mm on a DSLR, unless it's a full frame DSLR then it's around 28mm, then on a point and shoot camera it's around 5 to 6mm. Maybe confusing, but necessary to have a base line.

Sure I agree, focal length is solely a function of the actual length of a lens, but from there everything depends on the size of the film to determine what the actual field of view is. And determining the field of view has everything to do with the function of the lens on the body.

I agree as long as it is perfectly clear that it is a Field of View equivilent - that is what changes. - TF

[EOSThree]

Yeah, I wholeheartedly agree that the field of view changes. I think a lot of the confusion is created by this very statement though.

Someone will come on to a site like this and ask about an 18-55 lens. Someone will say it becomes a 29-88mm. Then others will come on and say it doesn't become anything, but the field of view changes. Or someone will say the body is cropping the lens and it's the equivalent of a 29-88mm lens if used on a 35mm camera. Then someone else will say, it acts like a 29-88mm lens if used on a FF camera. The list goes on. Now the OP has 4 different posts seemingly saying 4 different things, but all, in reality, saying the same thing.

I think the above type arguments are where the confusion comes. It's all semantics. They are all saying basically the same thing, maybe not in the correct manner, but the truth is that an 18mm lens on an aps C camera body acts, becomes, is cropped to, is the equivalent of, had the field of view of, a 29mm lens on a 35mm film body, and that equates to what is considered a wide angle lens. I think there is far to much righteousness in somehow having to state that no, it does not become, act as if, is cropped to, is the equivalent of, etc, but has the same field of view as...

Most people could give a rats ass about FOV. They want to know if it's wide enough for landscapes, or long enough for a portrait, or long enough to get a shot of the Cardinal at the feeder. At that point, it just doesn't matter how it's described. If I say his 5.7mm lens becomes a 28mm lens and that's a decent enough wide angle for landscapes. Doesn't that describe what he is looking for? He doesn't care that the sensor size is actually cropping the frame and the 5.7mm has the equivalent FOV of a 28mm lens. He just wants a lens for landscapes.

I know I have never thought of a 28mm lens having a 65 degree FOV or a 50mm having a 40 degree FOV or a 300mm having a 7 degree FOV. I simply think in terms of the object in the frame getting bigger or smaller. Maybe too simple for some, or even most, but I have never shot a scene thinking I needed a lens with a 65 degree FOV, but I think that would be best captured by a wide angle, or I need a telephoto for that...

[photophorous]

Just thought I'd add my two cents. This whole concept of equivalent focal lengths was never really discussed before digital came along with much smaller formats. When that first happened, it made perfect sense to compare it to 35mm film, because everyone knew what that meant. As time goes by, less and less people are familiar with 35mm film, so these comparisons don't make sense.

My suggestion for explaining this to a new shooter is to ask them if they are experienced with 35mm film and if they're not, then leave this equivalency discussion until after the basic concepts of wide, standard, telephoto, and DOF are already understood. At that point, it'll make more sense. But really, I think the important take away from this discussion is to be careful about how you answer questions for new shooters. Consider what they really need to know, and try to remember what you were thinking when you started. That's what matters. The rest of this is just semantics.

Paul

[Loupey]

As long as there remains no standard sensor size in digital photography, people will want to compare equipment against another known standard (35mm film in this case).

Sure if we all stayed within our 1.0x, 1.3x, 1.5x, 1.6x, or 2.0x "crop factor" systems we would all know precisely what focal lengths delivered within our own systems. But people tend to want to emulate the results of others who use other systems and so the "equivalentcy" comes into play.

As for compact point-and-shoot cameras, how many people really know/care what size the imaging sensor is (or even the crop factor for that matter)? And so the vast majority will simply pick up a P&S, not even look at the stated focal length specifications right on the lens, and ask "what is this lens equivalent to?" - and that's good enough for them.

[Franglais]

The first thing to do is to define some standard terms and what they mean in terms of view. Stuff like "Normal", "Wide-angle", "Telephoto" etc.

The place to do it is Wikipedia. It's the Internet encyclopedia and we're on Internet. There are already some definitions but they still use 35mm film focal lengths instead of angle of view.:

http://en.wikipedia.org/wiki/Wide-angle_lens

Include some images as examples and pointers to camera manufacturers brochures as supporting documentation and you have maybe done your good deed to humanity for the day.

[OldClicker]

The first thing to do is to define some standard terms and what they mean in terms of view. Stuff like "Normal", "Wide-angle", "Telephoto" etc.

The place to do it is Wikipedia. It's the Internet encyclopedia and we're on Internet. There are already some definitions but they still use 35mm film focal lengths instead of angle of view.:

http://en.wikipedia.org/wiki/Wide-angle_lens

Include some images as examples and pointers to camera manufacturers brochures as supporting documentation and you have maybe done your good deed to humanity for the day.

I would say that these are purely subjective terms that defy standardization both in what they are and in their use. - TF

[Franglais]

I just noticed that "Focal length in 35 mm film" is part of the EXIF 2.2 standard. That means that it's included in most of the JPG's written by our cameras and it's not going to go away.

Better to accept it.

[OldClicker]

I just noticed that "Focal length in 35 mm film" is part of the EXIF 2.2 standard. That means that it's included in most of the JPG's written by our cameras and it's not going to go away.

Better to accept it.

That does not seem to make it any less confusing or more useful. - TF