Napioa - Wind Origins

Napioa - Wind Origins
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When one uses a Nikon DX (APS-C) camera on an FX camera body, the camera automatically enters a "DX crop mode", using only the center portion of the sensor to match the DX format, as explained on Nikon's web site.

The FX format is roughly 36×24mm, while DX is 24×16mm, and it's this smaller size that DX crop mode uses. Notice that the short edge of the FX format is equal to the long edge of DX — and of course the image circle is perfectly round, not oblong. Do any Nikon full-frame cameras allow a "square DX" format, either 24×24mm (with some possible vignetting in the extreme corners) or slightly reduced?

share|improve this question
Quick answer, No. But you can however compose your square format image in camera, then just crop out what you don't need in post. Turn on rule-of-thirds guide to help you with framing the image in the viewfinder. Also, check the manual for "Translucent Masking"! Side note: I'll never understand why would someone spend a lot of money for FX sensor then place DX lens over it. I guess if you are sports/wild life shooter, you might need that extra reach. But again there are tele-converters. If you place DX lens, on D700 for example, you get 5MP's image from effective 12.1MPs. – Alen Mar 8 '12 at 5:42
Also check out DX crop mode guide – Alen Mar 8 '12 at 5:46
For many years, Nikon didn't have any FX DSLRs, so someone who hoarded optics back then might now be stuck sitting on a pile of DX lenses. If he/she happens to like square format, this is a natural question to ask. – Imre Mar 8 '12 at 8:23
@Imre Why upgrade to FX body in the first place, if most of the gear is DX? Sure it could be because of better low-light performance, dynamic range and whatnot but you are shortchanging the capabilities of the FX sensor. And eventually you will have to take a plunge and actually buy a lens that is designed for FX. And I'm not saying I have a problem with the question, if one wants to use DX lenses on FX sensor be my guest, but for me it doesn't make sense. – Alen Mar 8 '12 at 9:02
@Alen: if one is cropping to square anyway, the DX lenses basically cover the square center of the FX sensor, beyond the DX crop. So, in such a mode, one would actually not be missing out at all. – mattdm Mar 8 '12 at 14:40
up vote 6 down vote accepted

Square format is not supported, but 5:4 aspect ratio offered by D3, D3s, D800 and D800E is only slightly wider, 30mm. The nice thing is that the viewfinder is electronically masked, so you can compose with good precision. This aspect ratio is not provided on a D700 or D3x.

Alternatively, you could always crop in post.

Of course, you'll also need to disable Auto DX Crop.

share|improve this answer
While Nikon (or anyone else with a similar lens mount compatibility) could theoretically offer, say, a 20.3-and-a-bit-mm square crop, it wouldn't be compatible with the tulip-shaped lens hoods usually included with the smaller-format lenses. Since vignetting is almost always an issue already with DX-format lenses, I can see avoiding that potential source of bad PR—no matter how many caveats you put in the manual, it's always going to be Nikon's fault in a lot of minds. – user2719 Mar 8 '12 at 18:13

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