woodyd Loc: Israel

Just joined the forum and i'd appreciate some views from members please:

I started taking photographs many years ago with a Nikkormat FT3 35mm camera. After a long absence from photography I entered the digital world with a Nikon D3200 and I'm very happy with it although none of my old Nikor lenses will work on the D3200. I can see the images perfectly but nothing else functions. It took me quite a while to understand the effect that a smaller sensor has on field of view. However, before I fully understood this, I found myself looking at adds for lenses, where a lens of say 50mm on a full frame 35mm would be touted as a 75mm on a smaller sensor, i.e., my D3200. I got all excited and purchased a Tamron 70-300 zoom thinking that the 300mm would give me 450mm on my D3200. Wrong wrong wrong. I started swapping my prime lenses from my Nikkormat days onto my D3200 and found that the images were the same size. Yes, the D3200 maybe doesn't let one see the same field of view as the full frame Nikkormat, but the image remains the same size. The 50mm does not magnify to 75mm equivalent. So I now understand the difference between field of view and image size! I look at adverts for lenses and I see the words" 300mm is equivalent to a 450mm on APS-C." To me this is wrong. When you put a full frame 300mm lens on a smaller sensor, it doesn't magnify the image at all. You just see less of it and seeing less of an image does not bring it any closer!

I'd like to hear what other readers have to say. Am I wrong?

Thanks

Woody

jerryc41 Loc: Catskill Mts of NY

Welcome to our forum!

Yes, this can be confusing, and it always generates arguments here. An FX lens on a DX body will seem to act as a longer telephoto. That's because it's actually cropping by means of the sensor. Others will give you loads of explanations, but take a look at 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

Welcome Woody!

It's a very long subject as it deals with a lot of things but let me start about 1 point.
You have the FT3 and the lenses that you have should be AI lenses. These can be used on the D3200 in manual mode and no meter. The FT3 is fully manual so using the D3200 on manual shouldn't be any problem to you. You don't have the meter but with the D3200 you can just make test shots then adjust.

Clapperboard

woodyd "I look at adverts for lenses and I see the words" 300mm is equivalent to a 450mm on APS-C." To me this is wrong. When you put a full frame 300mm lens on a smaller sensor, it doesn't magnify the image at all. You just see less of it and seeing less of an image does not bring it any closer!

I'd like to hear what other readers have to say. Am I wrong?"

No! You are absolutely right and it's not at all confusing. The 'crop sensor' is just that. It 'crops' the image. Just the outside of the image. Everything else works just the same. There are plenty of situation where the crop sensor is an advantage. Unfortunately as regards to increasing focal length it does not.
I don't know why people find this an item for 'argument' nor why there can be any confusion. The application of the simplest logical thought makes it abundantly clear as you have grasped.

jeep_daddy Loc: Prescott AZ

Your right, it doesn't bring it any closer, but it does give it the appearance that it's closer. That's why they call them crop sensors. It's like taking a picture with the 35mm camera body and then cropping the negative 50% and then using the enlarger to print it back on the same size paper as the first one.

BebuLamar

Just checking the viewfinder magnification of the FT3 and the D3200. I think if you mount the same lens on both the image on the D3200 is actually a little bit smaller than that of the FT3.

woodyd Loc: Israel

So am I right or wrong in saying that a FX lens on a DX body gives a smaller field of view which gives the illusion of a bigger image but does not actually magnify the image? As focal length changes so do the characteristics of the lens. An FX lens on a DX body maintains the same characteristics pertaining to its focal length regardless of the size of the sensor?

Hank Radt

It confused the heck out of me at first as well, particularly when I read, as you did, various articles and marketing pieces. But, with the help of the UHHers, I finally got it. Then, of course, I found this article, which confirms (and which I now keep handy when the question comes up), including some illustrative images:

https://bkloflin.wordpress.com/2014/12/15/understanding-the-myth-of-crop-sensor-cameras/

woodyd Loc: Israel

Yes the d3200 viewfinder is different from the Nikkormat

Just parked my AI 50mm on the D3200 and it works perfectly in manual mode. Brilliant!!!! thanks for that.

Now the big one. Where do I get batteries for my old Gossen Luna 6?

Marionsho Loc: Kansas

Welcome to the Hog, woodyd.
The crop factor is only relative. We've had heated discussions in the past, that were quite fun, but I've never heard it called
"deceptive advertising".
Marion

Dngallagher Loc: Wilmington De.

A lens on a DX body will be the focal length of the lens, but the field of view will be based on the sensor. A DX camera is a CROP sensor camera, a Nikon crop factor is 1.5, so the field of view of a 200 mm lens will be a view similar to a 300 mm lens on an FX body, but it will still be a 200 mm lens.

An FX lens used on a DX body will be the focal length of the lens, but the field of view will be 1.5 times the focal length due to the sensor size (crop factor).

https://www.nikonusa.com/en/learn-and-explore/a/products-and-innovation/the-dx-and-fx-formats.html#

boberic Loc: Quiet Corner, Connecticut. Ex long Islander

I know that this statement is intuitively strange, But you are both right and wrong. A 50 mm lens will always be a 50mm lens regardless of the crop factor. And viewing angle is what telephoto lenses are all about. A wide angle lens is exactly that. A 30 mm lens "sees" a wider view than a 300 mm lens, which send a smaller (narrow) circle to the sensor. Put that 50mm lens on a "crop sensor" camera is sends a smaller "cropped" circle to the sensor. The same as cropping out part of the picture in post. You may (or may not) notice the difference thriough the view finder or the screen, but you will notice the difference wnen you view the picture on the computer or print. So in reality when the advertisement says that a 30mm is the same as a 45 mm on a crop sensor, it's more accurate to say the "Equivilence" of a 45mm.

Steve Perry Loc: Sylvania, Ohio

This is correct. A 300mm is a 300mm regardless of what portion of the image circle the sensor behind it is recording. The characteristics of the lens remain the same.

woodyd Loc: Israel

Thank you all for replying to me so promptly. I very much appreciate it. I have read the articles in the links supplied and feel better about it :-)

I still maintain that its deceptive to say that a 300mm FX lens is equivalent to a 450mm on a DX body.

Hank Radt

Nice to see a face that I've seen on videos! Particularly loved your piece on lens filter protection - most sensible thing I've seen on this subject.