How much bigger does an object appear when going from 300mm to 400mm telephoto? I am considering buying a 400mm telephoto and I have a 300mm telephoto now. What can I expect by going...

Bigbeartom44

I am considering buying a 400mm telephoto and I have a 300mm telephoto now. What can I expect by going to the longer telephoto. Will the image be 50% larger or 100% or something else? From some rudiment experiments I have done it appears that the image doubles when the telephoto doubles as going from 200mm to 400mm but not exactly. Any ideas?

Jay Pat Loc: Round Rock, Texas, USA

This simulator may be helpful, for you.
Canon-https://www.learn.usa.canon.com/resources/articles/Comparators/fov-comparator.shtml
Pat

craggycrossers Loc: Robin Hood Country, UK

Bigbeartom44 wrote:

I am considering buying a 400mm telephoto and I have a 300mm telephoto now. What can I expect by going to the longer telephoto. Will the image be 50% larger or 100% or something else? From some rudiment experiments I have done it appears that the image doubles when the telephoto doubles as going from 200mm to 400mm but not exactly. Any ideas?

This will help, I think ......

http://www.europe-nikon.com/en_GB/learn_explore/nikkor_lens_simulator.page

boberic Loc: Quiet Corner, Connecticut. Ex long Islander

100mm is 1/3 of 300mmso there would be a 33% increase

marki3rd Loc: Columbus, Indiana

boberic wrote:

100mm is 1/3 of 300mmso there would be a 33% increase

Huhh?

ken_stern Loc: Yorba Linda, Ca

All via a full size sensor
@ 300mm an object will appear to be 6 times larger & @ 400mm that same object will appear to be 8 times larger -- That is larger then what the object will appear through a 50mm lens mounted with a full size (24mm by 35mm) sensor

melismus Loc: Chesapeake Bay Country

One and a third times inccrease.

jerryc41 Loc: Catskill Mts of NY

More lens simulators.

http://imaging.nikon.com/lineup/lens/simulator/
http://www.dpreview.com/galleries/9059751105/photos/2518330/olympus-zuiko-lens-field-of-view-comparison

BebuLamar

marki3rd wrote:

Huhh?

Yes it's 33% increase. If an object is 1" with the 300mm lens it will be 1.33" with the 400mm lens.

drucker Loc: Oregon

Barring major differences in lens design (both lenses designed for the same camera/format), changing the focal length is a pure mathematical function. e.g. A lens with a focal length of 400mm will produce an image twice as large as a 200mm lens.

In the original request the comparison was 300mm vs. 400mm. So, the larger lens is 100mm longer. 100 is one-third of 300. So the image of the 400mm will be 1.333 times the size of the 300mm image.

jerryc41 Loc: Catskill Mts of NY

Bigbeartom44 wrote:

I am considering buying a 400mm telephoto and I have a 300mm telephoto now. What can I expect by going to the longer telephoto. Will the image be 50% larger or 100% or something else? From some rudiment experiments I have done it appears that the image doubles when the telephoto doubles as going from 200mm to 400mm but not exactly. Any ideas?

I'll order one of each from Amazon and let your know.

Gene51 Loc: Yonkers, NY, now in LSD (LowerSlowerDelaware)

Bigbeartom44 wrote:

I am considering buying a 400mm telephoto and I have a 300mm telephoto now. What can I expect by going to the longer telephoto. Will the image be 50% larger or 100% or something else? From some rudiment experiments I have done it appears that the image doubles when the telephoto doubles as going from 200mm to 400mm but not exactly. Any ideas?

Part of the answer is the difference in size, but another important consideration, I am assuming you are shooting birds and other wildlife, is the ability to crop the image. Depending on which lenses you are comparing, the 400mm may be considerably sharper that you 300. If your camera has enough megapixels, with the extra sharpness you should be able to crop the image and give you some additional image magnification.

If you are using a 300 F2.8, then the answer is simple. Get a 1.4x teleconverter. That will give you a 420mm F4 lens that will work extremely well. If you are using a zoom that is F5.6 or F6.3 max aperture at 300mm, then I'd pass on the TC.

This is a 2030x2901 crop from a 4912x7360 image. I used a D800 and a 150-600 Sigma Sport, and I was about 35-40 ft away. You should get similar results if you are using a crop sensor camera and a sharp 400mm lens.

(Download)

Bigbeartom44

Thanks all for the input. The "Nikkor lens simulator" was a big help as I got to see the differences first hand and I especially want to thank craggycrossers. For every doubling of the length in mm, the image size doubles. I have a Nikkor 55-300mm now and I am thinking about the new Sigma 100-400mm. I am using a Nikon d5300 which is a crop sensor. I am aware that the Nikkor is not in the same category as the Sigma as to sharpness. I have been photographing a bald eagle from about 300 yards and the image is quite small. At the most, I can blow it up by 50%. I am using a Vanguard tripod which is a monster. I'm not sure that the Sigma will be adequate. Maybe I should use something longer, like 500mm or 600mm. Any advice?

Gene51 Loc: Yonkers, NY, now in LSD (LowerSlowerDelaware)

Bigbeartom44 wrote:

Thanks all for the input. The "Nikkor lens si... (show quote)

You could get a longer lens, in which case I'd recommend the Sigma Sport or the Tamron G2 - both 150-600. But my guess is that you'll need to figure out a way to get closer to the action. You may want to take a look at Sharron Crocker's Untamed NY bird albums. She shoots exclusively with a Canon 5d Mk III and a 400mm lens, though some of her earlier shots were done with a 7d Mk II. She has since pretty much stopped using the crop camera because she sees the difference in quality with the full frame camera. All her bird shots are done hand-held, and her 400mm F5.6 Canon L does not have optical stabilization.

https://untamednewyork.smugmug.com/Birds

I'd hate to see you spend money and not get much better results than you are now getting.

a6k Loc: Detroit & Sanibel

Bigbeartom44 wrote:

..snip.. For every doubling of the length in mm, the image size doubles. ...snip..

That is true. The linear dimensions are linearly proportional to the actual, physical focal length. But, it's just elementary geometry that if you double the linear dimensions you quadruple the area and that can affect image quality.