Nikon Focal length question: I understand that if I were to put a Nikon FD 100mm lens on a Nikon crop sensor camera such as a D7100 the ' effective ' focal length would be 150mm. My...

Lille Loc: Upstate, NY

I understand that if I were to put a Nikon FD 100mm lens on a Nikon crop sensor camera such as a D7100 the ' effective ' focal length would be 150mm.

My question is what would be the ' effective ' focal length of a Nikon FX lens of that same crop sensor camera ?

Thanks,

Lille

rmalarz Loc: Tempe, Arizona

You can calculate the approximate apparent focal length by multiplying the focal length by 1.5.
35mm approx. = 50mm
50mm approx. = 75mm
100mm aprox. = 150mm
etc.
--Bob

Lille wrote:

I understand that if I were to put a Nikon FD 100mm lens on a Nikon crop sensor camera such as a D7100 the ' effective ' focal length would be 150mm.

My question is what would be the ' effective ' focal length of a Nikon FX lens of that same crop sensor camera ?

Thanks,

Lille

RWR Loc: La Mesa, CA

Lille wrote:

I understand that if I were to put a Nikon FD 100mm lens on a Nikon crop sensor camera such as a D7100 the ' effective ' focal length would be 150mm.

My question is what would be the ' effective ' focal length of a Nikon FX lens of that same crop sensor camera ?

Thanks,

Lille

The effective focal length would be 150mm.

Lille Loc: Upstate, NY

Thank you !

imagemeister Loc: mid east Florida

Lille wrote:

I understand that if I were to put a Nikon FD 100mm lens on a Nikon crop sensor camera such as a D7100 the ' effective ' focal length would be 150mm.

My question is what would be the ' effective ' focal length of a Nikon FX lens of that same crop sensor camera ?

Thanks,

Lille

IMO, "effective" is a confusing misnomer - and should instead be stated - "equivalent Full Frame field of view" - to leave no doubts as to what the reference is ! ......Just so we all understand perfectly well.

MT Shooter Loc: Montana

Lille wrote:

I understand that if I were to put a Nikon FD 100mm lens on a Nikon crop sensor camera such as a D7100 the ' effective ' focal length would be 150mm.

My question is what would be the ' effective ' focal length of a Nikon FX lens of that same crop sensor camera ?

Thanks,

Lille

To answer the rest of your question, ANY lens, be it FX or DX, when mounted upon a crop sensor body would require the factoring of the 1.5X multiplier to yield the effective field of view of the same lens mounted on an FX sensored body.

Lille Loc: Upstate, NY

OK I got it.

Thanks all for your answers.

jeep_daddy Loc: Prescott AZ

Same

Lille wrote:

I understand that if I were to put a Nikon FD 100mm lens on a Nikon crop sensor camera such as a D7100 the ' effective ' focal length would be 150mm.

My question is what would be the ' effective ' focal length of a Nikon FX lens of that same crop sensor camera ?

Thanks,

Lille

rehess Loc: South Bend, Indiana, USA

The bottom line is that multiplier for "effective focal length" depends on the sensor only.

Every 28mm lens will act exactly the same as the others.

Every 50mm lens will act exactly the same as the others.

Every 300mm lens will act exactly the same as the others.

OddJobber Loc: Portland, OR

I'm assuming that "Nikon FD 100mm lens" was a typo?
FD lenses are the older Canon mount, which can be mounted on a Nikon body with an adapter. They are full frame lenses so the 1.5 factor would still apply.

Fotomacher Loc: Toronto

rmalarz wrote:

You can calculate the approximate apparent focal length by multiplying the focal length by 1.5.
35mm approx. = 50mm
50mm approx. = 75mm
100mm aprox. = 150mm
etc.
--Bob

For those who are confused by all of this, I’d like to explain that the Nikon FX sensor is approximately the same size as a 35mm film frame. That’s why it is referred to as “full frame”. The DX sensor is 2/3 the size of the FX sensor and therefore it is “cropped”. The effective focal length or equivalence factor results since the field of view of the image on a DX sensor will be the stated focal length of the lens multiplied by the reciprocal of the crop factor, which is 3/2 or 1.5.

cameraf4 Loc: Delaware

Lille, all these "conversions" are because, when digital SLRs first came out, most folks buying them had been using 35mm film cameras for some time (in my case, a LONG time). So the "conversions" are meant to let experienced-with-film-camera shooters understand the "effect" they will get when they use a camera with an AFS-C (crop) size sensor. The conversion works well for folks who "hang-out" at the telephoto end (wild life, sports, etc). But didn't work well for a Landscape guy like me. On a crop-sensor camera, my "extreme wide-angle" 20mm lens gave the results I would expect from a "barely wide-angle" 30mm lens. For me, going to FF (full-frame, FX) was a God send.

lamiaceae Loc: San Luis Obispo County, CA

Lille wrote:

I understand that if I were to put a Nikon FD 100mm lens on a Nikon crop sensor camera such as a D7100 the ' effective ' focal length would be 150mm.

My question is what would be the ' effective ' focal length of a Nikon FX lens of that same crop sensor camera ?

Thanks,

Lille

FD is probably a typo for FX (I hope).

lamiaceae Loc: San Luis Obispo County, CA

cameraf4 wrote:

Lille, all these "conversions" are becau... (show quote)

I'm in that same boat. But have not been able to afford a FF yet (other than my film cameras so to speak).

cthahn

100mm