question about full frame lenses

[Keith Baran]

Are there any disadvantages when using a full frame lens on a digital camera with a smaller sensor?
I’m thinking of purchasing a Tamron full frame lens for my Pentax k10.
Any and all advice is appreciated
Keith Baran

 

[Overread]

Short answer - no.
Longer answer - the only difference you will see is that instead of displaying the whole of what the lens is capable of seeing, your camera will only capture the middle areas of the lens image - the rest is lost. This does not affect what you see in the viewfinder either - you will see only the image that your camera will capture - the "missing" bits will not be shown to you.
The overall effect of this is that the image you get will look as if you were using a longer focal length lens at the time - which is why smaller sensor cameras are popular with people that want longer focal lengths.

 

[tsaraleksi]

The only disadvantage would be that it will weigh more than a lens that was built specifically for a crop format camera, but this is hardly a major concern. Also, a lens that has been designed for a film camera will not take the field of view crop into account in its range, so a lot of lenses that were designed as wide-to-medium zooms have become medium-long zooms. But you will be able to see that in the ranges listed, so it's not really a bit deal.

 

[clupica]

Others may disagree but I think the opposite is true. The best lens to put on an APS sensor is a full-frame lens. Why you might ask? A lens is generally sharper toward the center than at the eges. The edges are prone to softness, barrel distortion, pin-cushioning, and greater lateral and transverse Chromatic Aberration. If you're shooting in the center of the lens many of these problems will be lessened; some to the point of non-existance. Also, a full frame digital lens is likely to be geared more toward the upper end of the market, meaning that it's probably better glass than a similar offering for an APS.

I've been thinking of upgrading to a full-frame sensor but can't shake the fact that full-frame lenses for an APS sensor would yield more bang for the buck.

Charlie

 

[Overread]

Very true Clupica with regard to the area of best quality for a lens.
As for the higher end of the market it really depends. Canon don't make any L cropsensor specific lenses becuase they keep their L lens range for fullframe only. However some of the crop sensor lenses can deliver very high quality results.

 

[Dao]

In addition, for lens that is designed for full frame/35mm film cameras and use it in a smaller sensor body, you will have less issue with Vignetting as well.

 

[Stratman]

I use a lot of old full frame lenses on my K10D with no problems. I say go for it !!

 

[Craddie]

I agree completely with Clupika. I try to by FX glass even though I have a DX sensor camera. The middle is generally the sweet spot, (sharper, no vignetting etc.), the only drawback is weight and size.

The other upside is future compatibility. FX cameras will become more and more affordable - I'm anticipating a move to FX in 2-3yrs, and I'd rather not have to invest in good lenses twice if it can be avoided.

 

[FlyingFly]

The only disadvantage is that you might have to bring 2 lenses to cover wide to medium focal length range. For example, Tamron 28-75/2.8 is a good standard zoom for full frame. But on APS you need another super-wide lens such as 17-35/2.8-4 to extend the wide end.

This increases not only budget but also weight.

 

[Keith Baran]

Thanx for all the input, it was very informative
I went with the [FONT=&quot]Tamron AF 28-75mm f/2.8.
Merry Christmas!
[/FONT][FONT=&quot] [/FONT]

 

[ksmattfish]

I went with the [FONT=&quot]Tamron AF 28-75mm f/2.8.
Merry Christmas!
[/FONT][FONT=&quot] [/FONT]

That's a good one!

 

[Village Idiot]

No one mentioned aperture.

The DoF will be different between a camera with an APS-C sensor than a camera with a FF sensor at the same focal length and aperture.

Iirc, because of the crop and using the center of the lens, the part which is flat, you get less DoF on a camera with a smaller sensor than with one that utilizes the whole part of the lens and the curvature.

 

[tsaraleksi]

No one mentioned aperture.

The DoF will be different between a camera with an APS-C sensor than a camera with a FF sensor at the same focal length and aperture.

Iirc, because of the crop and using the center of the lens, the part which is flat, you get less DoF on a camera with a smaller sensor than with one that utilizes the whole part of the lens and the curvature.

The DoF difference is a result of the sensor size itself, and the actual focal length needed to achieve a given apparent focal length. Longer lenses will always give you shallower depth of field. So, if you have a crop sensor camera and a full frame camera, and want to get an 80/85mm field of view, on your crop camera you need a 50mm lens, on your full frame camera you need an 85mm lens. The 85 will give you shallower depth of field.

 

[FlyingFly]

No one mentioned aperture.

The DoF will be different between a camera with an APS-C sensor than a camera with a FF sensor at the same focal length and aperture.

Iirc, because of the crop and using the center of the lens, the part which is flat, you get less DoF on a camera with a smaller sensor than with one that utilizes the whole part of the lens and the curvature.

That's right. Yet Keith Baran is comparing full frame lens and APS lens, instead of full frame and APS camera body

 

[LWW]

Others may disagree but I think the opposite is true. The best lens to put on an APS sensor is a full-frame lens. Why you might ask? A lens is generally sharper toward the center than at the eges. The edges are prone to softness, barrel distortion, pin-cushioning, and greater lateral and transverse Chromatic Aberration. If you're shooting in the center of the lens many of these problems will be lessened; some to the point of non-existance. Also, a full frame digital lens is likely to be geared more toward the upper end of the market, meaning that it's probably better glass than a similar offering for an APS.

I've been thinking of upgrading to a full-frame sensor but can't shake the fact that full-frame lenses for an APS sensor would yield more bang for the buck.

Charlie

*DING*

LWW