jerryc41 Loc: Catskill Mts of NY

Here are links to a couple of lens simulators. I don't recall if they cover DX on FX.

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

RolandDieter

Peterff wrote, correctly, that many compromises are made in lenses that cover a large zoom range and that the greater the range the more the compromises. But -- the amount of necessary compromise varies by the sensor size the lens is designed to cover. An APS-C lens of 16-70mm is gives the same image as a 24-104mm full frame. But, the former has a zoom range of only 54mm (70 minus 16) whereas the full frame has a range of 81mm (104 minus 24). This means the APS-C can be made with fewer compromises. This becomes more important for longer zooms. So it seems what we have, when other things are equal, is a sensor advantage for full frame and a lens advantage for APS-C.

rehess Loc: South Bend, Indiana, USA

That depends on which system. This is where the term "vignetting" comes into play; if you look at the images on page 1, at the wider focal lengths, the user would have to crop the picture to get a nice-looking image, but at longer focal length the user would have full resolution of his/her sensor. I know from experience that I can mount my Sigma 10-20mm k_mount lens on a FF camera {namely a 30-year-old film camera}; up to around 15mm I get vignetting, but beyond that the lens functions just as any other K-mount lens would.

Ed Walker Loc: Eclectic, Alabama U.S.A.

Sorry, I thought I was replying to someone who had told me to have fun.

Peterff Loc: O'er The Hills and Far Away, in Themyscira.

That is quite a concise way of expressing it. Except when cost, weight, and bulk are brought into the equation.

Another consideration from the lens point of view might simply the ratio of short to long focal length regardless of sensor size.

Thoughts?

mwsilvers Loc: Central New Jersey

What made it confusing was you did not quote the person you were replying to. If you had, your post would have made sense in context. Its always a good idea to use Quote Reply when responding to a particular post.

RolandDieter

Bonjac said he heard that an APS-C lens on full frame will only get 40% of the resolution. It is actually about 65% (the 40% is close to what you lose, not to what you keep). This applies when you have a full-frame camera where you can set it to capture in APS-C format. As Robert Jerl's images show, you can sometimes get far more than the 60% - 65% if you just shoot with the APS-C lens and then crop out the vignetting. How much resolution do you keep? As his images show, it will vary by lens and, with zooms, by how much you zoom. Some lenses are not a big problem, some are. With some newer full-frame cameras that have more resolution than you will probably need, losing 1/3 of resolution is probably not an issue. Full frame means more bulk, more weight and often less flexibility. What trade-off is best for what you are shooting? Myself, I have a full-frame on which my wide angle is a an APS-C 10-18mm zoom, the the other lenses are full frame. For other shooting I take my micro 4/3. And for occasions (lots of walking, hilly terrain) where bulk/weight is really critical, high quality gear with 1" sensors is my choice.

rehess Loc: South Bend, Indiana, USA

If every lens exactly covered the sensor it was designed for, then an APS-C lens would cover approx 40% of an FF sensor, but some are much more generous than that. When Pentax created the K-1, they programmed in how to crop each current Pentax “DA” {APS-C} lens.