Backyard wildlife zoom question factoring distance

Question

I'm quite new to photograhpy/videography and I only have a limited budget of $800.00US for a lens.

As per Kai's request allow me to pose the question centered around the discussion I initiated:

Which lenses could be considered on a micro four thirds camera to give me similar or better focal length and zoom as I had using a Canon APS-C with a 70-300mm lens?

I am using an MFT camera (BMPCC4K) for video and the lens I am considering is the Olympus 12-200mm f/3.5-6.3 lens mostly for it's zoom capability of 16.6x. It has a 35mm equivalent of 0.46x magnification.

I will always be using this lens outside on sunny days and I will be shooting the video at 24 fps HD. I will always have it mounted on a sturdy tripod for this type of video shooting so IS is not an issue.

The distance from my tripods to the area where I take pictures and record video is approx 70 feet.

My concern is that I will not be able to get close up shots or acceptable video footage being 70 feet away- even with 16.6x zoom and the magnification (.46x 35mm equivalent) because of the smaller format camera and smaller MFT lens.

I have no experience shooting video with MFT lenses but I understand the 12-200mm is a consumer grade lens for wildlife photography and videography- according to the Olympus website and reviews I've watched and read.

My previous experience is with a Canon 80D (APS-C sensor) using a 70-300mm IS II USM consumer lens at 29.97 fps in HD.

With that lens I was able to get fairly close pictures and video when fully zoomed in (from 70 feet away) and I am hoping I will be able to get at least the same zoom result FOV with the Olympus 12-200mm on the MFT camera, when shooting video.

The idea is to shoot pics with the Canon 80D and shoot video with the BMPCC4K.

I have watched many videos and have read many reviews and I know the Olympus 12-200mm lens gets soft in the long range and unless it's super blurry, it doesn't matter to me that much.

I will be shooting video of our garden too and I understand this lens has a good minimum focus distance, which I hope will be adequate for getting flower and plant footage, but again I have no experience with this lens, so I really don't know- which is why I'm here:).

Anyway, in a nutshell, I'm just hoping that with the proposed lens (Olympus 12-200mm) I will be able to zoom in and see the critters (squirrels and birds) fairly close like I can with my Canon 70-300mm.

To clarify a bit, I am not hoping to zoom in and see complex detail in bird feathers or look up a squirrels nose lol, but I'm hoping to get video footage of the animals' bodies filling out the frame when zooming in from 70 feet away.

I'm sure this is a very basic thing to understand but I need to be sure, so I wanted to consult with professionals or at least someone who could assure me I'm getting a proper lens for my backyard video recording activities.

Thanks so much for your time and hope to hear back soon.

Stay safe:).

Answer 1

Assuming all other things are equal:

• Your Canon 80D has a crop factor of 1.6. This means that your 300mm lens has an effective focal length of 300mm × 1.6 = 480mm.
• A micro-4/3s camera has a crop factor of 2.0. This means that a 200mm lens has an effective focal length of 200mm × 2.0 = 400mm, a bit less than the 300mm lens on the Canon.

Working backwards, your Canon lens has an effective focal length of 400mm at (400mm / 1.6) = 250mm, so if you set your 70-300mm to 250mm, that will give you something pretty similar to the focal length you can expect from the micro-4/3s. If that's good enough for you, things are probably OK.

Now, all other things aren't equal - most notably, the Canon sensor has an aspect ratio of 3:2 while the micro-4/3s is 4:3, and of course the sensors are different.

One other thing to note:

I am considering is the Olympus 12-200mm f/3.5-6.3 lens mostly for it's zoom capability of 16.6x.

For this use case, you don't care about zoom ratio. You're not bothered about the wide end of the range, just the telephoto end - a 100-300mm lens which has "only" a zoom ratio of 3× is better than a 10-200mm lens with a zoom ratio of 20×.

Answer 2

Given the ratio of the Canon APS-C crop factor (1.6) to the MFT (2.0) sensors, the equivalent of a 300mm on your camera is 300*1.6/2=240mm so a bit longer than your intended lens (200mm).

The zoom capability you mention is really a zoom range, but since your lens starts at 12mm which is a wide angle, the zoom factor from "normal" is smaller, more like 8x.

Your 12-200mm is really a "super-zoom" for people who don't like/want to change lenses. If you just want to use it as a zoom, there are more specialized lens that will zoom more such as the Olympus Zuiko 75-300mm (which will get you closer than your Canon 300mm).

Answer 3

The formula for determining the focal length required to fill the frame with a subject is pretty simple:

• FL= sensor(distance/size)

So for your example, to fill the width of an m4/3 sensor (18mm), from a distance of 70ft (21M), with a squirrel which is ~1.5ft long including tail (.5M) is:

• FL= 18(21/.5) = 756mm.

The closest to that is typically 800mm; but you probably don't want to completely fill the frame, so maybe 75 percent/600mm is the best choice.