topic Re: Questions About Nature Photography? I'm Here to Help! in General Discussion

Questions About Nature Photography? I'm Here to Help!

Tim — Tue, 22 Apr 2014 15:24:07 GMT

Hi Everyone! I'm Tim, a senior technician here at Canon. I'm going to be here on the Canon Forum, live later today, from 3:30-4:00pm EST to kick off a community discussion on Nature Photography! I'll be here to answer your questions, provide tips and bounce ideas around, so drop on by and join in on our conversation!

I'm a long time photographer with over fifteen years of technical and photographic experience with Canon and the imaging industry. I particularly enjoy working with full-frame cameras and Canon's Cinema EOS gear, and take every opportunity I can to capture the beauty of the Atlantic Ocean near my home.

Re: Questions About Nature Photography? I'm Here to Help!

clars — Tue, 22 Apr 2014 20:02:02 GMT

Regarding full-frame and crop sensors for shooting wildlife, do the crop sensors actually get you 1.6x closer? I know the sensor is larger on the full-frame, but how come the smaller crop sensors get you closer ot the subject or is it just appearing that way because of the tighter cropped image?

Re: Questions About Nature Photography? I'm Here to Help!

Tim — Tue, 22 Apr 2014 20:12:13 GMT

Hello Clars,

With regards to full frame cameras versus APS-C, there is a physical attribute of magnification with APS-C cameras (like the EOS Digital Rebel series). So, for example, if you were to use an EF 70-200mm f/2.8L IS II USM lens on an APS-C camera, the focal length becomes an effective 112-320mm, but only on APS-C. The reason being the difference in sensor size. Canon's EF standard was originally developed for the 35mm film size. So using an EF lens with full frame, focal lengths do not change. The APS-C sensor, being smaller, imparts a slight magnification ratio which, as you know, is 1.6 times.

So, for shooting wildlife, one benefit of using EF (over EF-S) on APS-C sensor cameras is the longer reach, you get more telephoto than originally bargained for, so to speak. The one downside is that you lose wide angle in this equation.

If you are interested in a camera that would both remain true to marked focal lengths on your EF series lens and deliver outstanding image capture ability, then a full frame camera like our EOS 5D Mark III, would be appropriate. This of course is not the only benefit of shooting full frame, but since your inquiry was lens oriented I've focused on that aspect specifically.

I hope this helps answer your question, and should you need further clarification or additional help - I trust you will let me know!

Re: Questions About Nature Photography? I'm Here to Help!

clars — Tue, 22 Apr 2014 20:19:42 GMT

Cheers Tim, it does help a ton. Had recently upgraded two 60D's to 6D's and was suprised. A pleasant suprise for how much more image I could get with the 6D, really help showed the natural habitat of the wild animals, but confused on why the subject seemed that much further away. To clarify the 1.6x magnification is a true zoom and not something I could achieve in post processing by increasing image 1.6 times?

Re: Questions About Nature Photography? I'm Here to Help!

hsbn — Tue, 22 Apr 2014 20:27:49 GMT

It's not a true zoom. It's still a crop. For example, your 60D is an 18Mpx camera. So if I have a 45Mpx full frame camera, I take the photo and crop it in post processing i will get the exactly same as your 60D. But there is no Canon 45Mpx camera.

Re: Questions About Nature Photography? I'm Here to Help!

Tim — Tue, 22 Apr 2014 20:52:57 GMT

Hello Again Clars,

If we look at the subject objectively, then there are two answers which I feel are equally considerable. Firstly, when shooting with an APS-C camera and an EF series lens, the magnification you're seeing is a true optical effect; it's not a "crop" in the normal sense [as would be with a “digital zoom”]. That being said, the optical effect of magnification is the result of using a lens which is designed to cover a 35mm [technically 36 x 24 mm] format on a sensor which is of a smaller dimension [22.3 x 14.9 mm]. The end result manifests as the 1.6x magnification ratio.

The second part of my answer is open to interpretation of sorts, and does not address APS-C cameras specifically in a physical attribute sense. So, if you took a photograph with a full frame camera then cropped , maintaining the aspect ratio of APS-C, then the end crop would be a similar image but only because you’re cropping, not because the lens is actually capturing a more telephoto image. Sometimes APS-C sensor cameras are referred to as "crop" frame cameras for this association to cropping an image in post-production.

So as you see, there are two ways to look at it. I mention both because I think it's important to understand why the effect occurs. The base answer to your question however, as I mentioned earlier, is that this magnification is a true optical principle and does indeed change the focal length of the lens.

Thanks for the great question by the way; I really appreciate you taking advantage of this chat. Did you have any other questions or was there anything else I can help with?

Re: Questions About Nature Photography? I'm Here to Help!

Tim — Tue, 22 Apr 2014 21:09:11 GMT

Hello HSBN, and thanks for joining our chat!

The zooming effect incurred on APS-C cameras when an EF series lens is used is an optical phenomenon due to the image circle being designed around larger sensor [or film plane] coverage. Since the EF lens series were originally designed to be 35mm film lenses [which subsequently influenced full frame digital] their coverage is more than what is needed for the smaller APS-C sensor, the end result of which is a ratio of 1.6x. But it is in fact a physical effect and not one of the cameras’ cropping the image to gain more zoom.

This is not an effect limited to 35mm cameras either; a normal lens on 35mm is about 50mm- on a medium format camera a normal lens, e.g. one with a similar angle of view, is more like 90mm and one step larger to the 4 x 5 large format, a "normal" lens is in the range of 150mm. Focal length as a marked value is always relative to the format the lens is designed to cover versus a fixed value.

Re: Questions About Nature Photography? I'm Here to Help!

ebiggs1 — Wed, 23 Apr 2014 14:35:34 GMT

Tim,

This may just be semantics but the focal length of a lens is fixed at manufacture and can not be changed afterward.

No matter what body, APS-C, FF or 4x5, etc. it is used on.

A 75-300mm lens is still a 75-300mm lens, whether it’s attached to a cropped-sensor camera or a full-frame.

What is changed is the “angle of view”. This refers to how much of a scene the lens covers. Fisheye lenses, the widest available, can capture 180-degrees. As you zoom in or change lenses to increase the focal length, the field of view narrows sometimes to just a few degrees. You can isolate small portions of the scene without moving closer to the subject.

Lens focal lengths are based on the physical characteristics of the lens so they are absolute values.

Re: Questions About Nature Photography? I'm Here to Help!

Skirball — Wed, 23 Apr 2014 14:44:06 GMT

@Tim wrote:

The zooming effect incurred on APS-C cameras when an EF series lens is used is an optical phenomenon due to the image circle being designed around larger sensor [or film plane] coverage. Since the EF lens series were originally designed to be 35mm film lenses [which subsequently influenced full frame digital] their coverage is more than what is needed for the smaller APS-C sensor, the end result of which is a ratio of 1.6x. But it is in fact a physical effect and not one of the cameras’ cropping the image to gain more zoom.

You're being very selective in your words. What you say is technically true, but misleading.

If you use an EF lens, a lens that will work on both full frame and APS-C cameras, there is no physical effect. It simply crops out the outer boarders. Yes, APS-C cameras allow use of different optics (i.e. smaller optics), but if anything that advantage lies in being able to offer cheaper lenses to do the equivilent of a FF option.

I disagree that the zooming is an optical effect, that implies (at least to me) that it's due to the optics. You're simply viewing a crop of the original image (35mm equiv) at a larger magnification. This applies to both the image you see in the viewfinder, and the image displayed on the computer monitor afterwards. It wouldn't be considered a zoom at all if it wasn't for the fact that you pack more pixels on the smaller chip. As noted above, if you made a FF sensor with the same pixel density you could crop out that inner section and get the identical "zoom effect".

Re: Questions About Nature Photography? I'm Here to Help!

ebiggs1 — Wed, 23 Apr 2014 15:46:57 GMT

Nothing changes about the lens; it's simply the amount of the image that is used from the back of the lens. Canon's EF Lenses still focus the image on the same plane as before, but sensors are smaller than 35mm sensors and do not capture the entire image. They don't actually “crop” the image, it simply is not there to begin with.

All lenses produce a round image not a square one so even FF sensors discard some of what the lens sees. And this is not technically a crop. It simply is not used. Ignored.

The most accurate definition for this is angle of acceptance or field of view. Whichever you prefer.

I realize the terminology of “crop sensor” has entered the photographic jargon but it is somewhat misleading. The bottom line is all DSLR's are full frame cameras since you get what you see in the viewfinder. More or less, that is, and the rest is just numbers printed on the outside of the lens to indicate what the lens is.

Re: Questions About Nature Photography? I'm Here to Help!

Skirball — Wed, 23 Apr 2014 17:36:00 GMT

I’m well aware of the physics behind the lens; nowhere did I claim it changes the lens. The rest of your stance is purely semantics. I don’t find the term misleading at all, the image captured by an APS-C sensor is indeed a crop of what would have been captured by a 35mm “full frame” sensor using the same lens. Most people don’t have that much difficulty understanding this concept, or utilization of the term. Some may misunderstand it, but such is the case any time you simplify something. It’s easier to say crop sensor than reference “the angle of acceptance afforded by an APC-S sensor relative to a 35mm sensor”. I’m going to stick with calling it a crop sensor, and know that most everyone I talk to knows what I mean, and the effect it has on the field of view.

Re: Questions About Nature Photography? I'm Here to Help!

ebiggs1 — Wed, 23 Apr 2014 19:52:45 GMT

The reply was not entirely directed towards you. But to both you and Tim so it reflected both.

But you are free to call the camera any thing you like. However, when trying to explain to a new person or someone that doesn't not know what is actually going on, it is somewhat confusing.

And the fact a “crop” camera does not actually crop anything is a reality.

It is easier to say “crop camera” and that phrase has entered our jargon. It is likely to remain but does not release us from explaining to new photographers what it really means.

I have talked with some new people that believe the focal length changes depending on what body it it used on. Some of them are right here on this forum. Unless we correct at least the basics, this is likely to continue. Not that is really matters to most people but the effort is there. Most people could care less what those numbers stamped on a lens mean.

You as a seasoned photographer should realize this. No, maybe not?

Re: Questions About Nature Photography? I'm Here to Help!

Skirball — Wed, 23 Apr 2014 21:21:28 GMT

@ebiggs1 wrote:

And the fact a “crop” camera does not actually crop anything is a reality.

No, it's not. It provided a cropped image relative to a 35mm sensor.

@ebiggs1 wrote:
You as a seasoned photographer should realize this. No, maybe not?

Heh. Ad hominem attack aside, not necessarily, no. As you implied, the numbers don’t actually mean anything, it’s only the result I get of one number relative to others. Do I care that the physical distance from the rear lens element to the image plane is 70mm in both systems? Or do I care that the APS-C system will show me, ahem, a cropped field of view relative to the 35mm system, about what I would get if I was at 112mm. The engineer in me likes to know how and why, but the photographer only cares about the image it provides.

Re: Questions About Nature Photography? I'm Here to Help!

ebiggs1 — Thu, 24 Apr 2014 12:24:43 GMT

No matter how many pretty pictures you show with colored lines on it, no crop takes place. The crop camera never sees that. It doesn't know it even exists. There is nothing to crop. Most DSLR owners never have or use a FF camera in first place. Nobody tries to claim P&S's are crop cameras. The 1 series cameras are generally not considered crop cameras. Are 4x5's considered enlargement cameras? No. Because this is all photographic jargon to try and explain the relationship of the focal length of the lens. You are entering a time where lot's of people never used a film camera so "crop camera" is actually meaningless to them. When they here that they think some sorta crop takes place in the camera and that is wrong. I'll bet Tim wishes he never said a word!

Re: Questions About Nature Photography? I'm Here to Help!

MikeSowsun — Thu, 24 Apr 2014 13:20:37 GMT

Put me in the camp with those who call them "crop" cameras. I say it is the perfect term to use because I think it does best job of describing the relationship between the various camera formats.

The 35mm SLR has become a sort of "Gold Standard" when it comes to photography, and everything else is either a crop camera or a large (or medium) format camera. Larger formats like 6x7 or 4x5 are not very well known, but most people have at least some knowledge of the 35mm Single Lens Reflex or SLR camera.

Even if the reader has never seen or heard of a 35mm film camera, they are bombarded with the 35mm focal length equivalent. This is evidenced by the fact that most photography websites and reviewers will include the 35mm equivalent when the focal length of any camera or camera/lens combination is talked about.

Re: Questions About Nature Photography? I'm Here to Help!

ebiggs1 — Thu, 24 Apr 2014 13:53:14 GMT

Mike I have no problem calling them “crop cameras” either. As I stated that has entered our jargon. It is likely here to stay. The only thing I try to do is explain what actually are the facts. Because the term is mis-leading.

Most of the people in my classes, these days have no idea what film or 35mm is. Also most do not go to the photography forums. They just want to shoot, in this case nature photos. Somebody inevitably brings up the word crop camera. Immediately that new person thinks the $1000 they just spent was on an inferior camera.

Re: Questions About Nature Photography? I'm Here to Help!

clars — Thu, 24 Apr 2014 15:50:07 GMT

Would just like to clarify, I fully understand the size difference of the sensors, how much image comes through the lens and is projected on the sensor, I grew up and studied using 35mm film, the question is not for shooting nature but for shooting wild wildlife and yet I still am not wrapping my mind around WHY or HOW an APS-C sensor is getting me 1.6x closer to that bear than my FF camera (both with the same lens setup).

To me the following equation does not make sense, but this is how it is:

APS-C Camera + 300mm = FF Camera + 300mm + 1.4extender (roughly)

Any how, rather enjoying the discussion.

Cheers.

Re: Questions About Nature Photography? I'm Here to Help!

MikeSowsun — Thu, 24 Apr 2014 16:54:33 GMT

Here is a simple way to understand it:

Take a full frame camera and then VERY carefully apply tape to the image sensor to mask off (crop) the sensor until it is the same size as your 1.6 crop camera.

Now take a photo. The photo will need to be cropped to remove the area that is not exposed. When you print that image or view it on a computer screen, it will be look as though it was taken with a lens that is 1.6 times longer.

Re: Questions About Nature Photography? I'm Here to Help!

clars — Thu, 24 Apr 2014 17:32:57 GMT

Correct Mike, thus it apears 1.6x closer but in fact is not.

So when a company describes a lens as a 600mm or a 960mm equivelant on a APS-C camera, it is infact misleading.

Bringing this question up because I have noticed other well published wildlife photographers shooting a subject only to remove their Mark III from the lense and put on a 70D to shoot the exact same angle, lighting, etc, when infact the same result could be achieved in post production.

Re: Questions About Nature Photography? I'm Here to Help!

MikeSowsun — Thu, 24 Apr 2014 17:43:02 GMT

The reason they remove their "Mark III" and use a 70D is so that the pixel density is higher on that "Cropped" image. If you had a huge megapixel camera, you wouldn't need to use the 70D.