Lens Focal Lengths & Subject Distances — Real World Examples?

[patagonialuke]

TLDR: I'm looking for uncropped photos where the distance to the subject is known (with any semblance of accuracy), as well as the focal length at which the image was taken. Goal is to get a better idea of what to expect in terms of the magnification provided by various focal lengths.

Longer Version:

I'm in the process of figuring out which longer lens to add to my small collection, now that I'm finally getting more serious about wildlife photography (I mostly shoot outdoor action sports). While there's tons of helpful general advice out there, I'm a bit surprised by how difficult it is to find useful examples of subjects at different distances and the relationship between that and focal length.

However, I figure if there are any photogs out there who also carry rangefinders and/or are good at judging distance, I'd find them here.

I've been inspired by the photography of many Roksliders here, and if any of you are able to provide some examples, I'd be very thankful. And I think this could be a helpful resource for others like me who are excited to learn more about the intricacies of wildlife photography in particular.

To start, here's a couple I took yesterday while trying to get an idea of the range / limitations of my longest setup. I'll leave focal lengths in full-frame equivalent to standardize things.

Body: Olympus OM-1 Mk.2 (micro-4/3 sensor)
Lens: Panasonic 35-100mm f2.8 (70-200mm FF equivalent)

Image 1 (uncropped, handheld)
Distance to Subject (closest elk): 262 yards
Focal Length (FF Equiv.): 200mm
Other Details: f/2.8 / ISO320 / 1/1000sec


Image 2 (uncropped, handheld, de-noised in LR)
Distance to Subject (dusky grouse): 15 yards ±2 yards
Focal Length (FF Equiv.): 200mm
Other Details: f/2.8 / ISO10,000 / 1/640sec

 

[JohnMC]

If I understand your question correctly you want to know what your field of view at a certain distance. If that the case this might help but requires some math. Look up your lens you will find something similar to link provided. Also this assuming you are shooting full frame camera. This is the lens I mostly use for wildlife. On one of the columns at link you see the field of view is:
Approx. 163 x 245 mm/6.42 x 9.65 inch (at 4.5 m/14.76 ft.)

So if you want to know the field of view at say 50 yards/150 feet you would divide 150 by 14.76 and get 10.16 then multiply 10.16 x 9.65 and get a field of view of roughly 98 inches or about 8.23 feet (horizontal landscape). At least this how I understand it.

I think this is correct also, if you are shooting cropped sensor say a APS sensor that is 1.6 you would divide the above number by 1.6 to get your field of view.

But if you are wanting to shoot wildlife the simple answer is get the most lens you are willing to pay for. With that said you can get some decent lens like a tamron or sigma 150-600 or similar from the company that makes your camera for not total crazy prices or even buy used.

Hope I understand your question correctly.

https://support.usa.canon.com/kb/s/article/ART174620

 

[patagonialuke]

If I understand your question correctly you want to know what your field of view at a certain distance.

Thank you very much for the response and info.

Yes, field of view is the actual thing I'm curious about; I don't know why I never thought to look into that instead of 'magnification'...

I think you've pretty much cleared it up for my purposes re: visualizing FOV for lenses with longer focal lengths.

If I know the FOV of lens 'A' and lens 'B,' I can just pull up a photo I took with lens A and crop it down by the ratio of the two lenses FOV's to emulate the FOV of lens B for the same shot / distance. If I'm right in assuming that, then that makes this a lot easier to grasp.

If others find it interesting, in the future, I may still post more photos on this thread with focal length and distance info. But for now, I think I'll start by renting the new Olympus 100-400mm f/5-6.3 and/or 150-600mm f/5-6.3.

Thanks again!