Full Frame vs DX

<p>Would someone please explain what the main benefits of a full frame camera (e.g. D3) are over a DX (e.g. D300). Obviously there are many other benefits with the more expensive camera but specifically - apart from being able to print larger photographs - what is gained from the full frame senser. Thanks</p>

<p>Full frame sensors generally have physically larger pixels which result in images with lower noise and better dynamic range.</p>

 

<p>The full-frame bodies also reduce depth-of-field; for some this level of control is a good thing (for example, if you like to throw backgrounds out of focus), for others the loss of depth-of-field poses additional challenge--for example with macro or landscape shots, when depth-of-field is often at a premium. The full-frame bodies also tend to have bigger & brighter viewfinders.</p>

<p>Also, the 35mm-sensor (let's call them that, rather than "full-frame") generally are built more expensively in other ways than the sensor alone, so the best of them are clearly superior in build to the APS-C-sensor cameras. This does not have to be this way, and you could argue that the 4/3rds approach is an exception, but it is generally true right now.</p>

<p>Potentially the wider spacing, etc of the 35mm-sensor array may allow the benefits that Rob mentioned, but this applies mostly to differences in the same <em><strong>generation</strong> </em> and <em><strong>type</strong> </em> of sensors. A newer APS-C sensor may well outperform an older 35mm sensor, especially as you reach back to older and older models.<br>

Technology does march on, and the makers of sensors are competing to produce ever more sophisticated arrays that will reduce noise (and, of course, cheapen production costs).</p>

<p>No doubt sensor cost will be increasingly a smaller part of the total price of the camera, but there are economies in both sensor production and lens design that I, at least, think make it likely that we should think of the relationship of the two formats as being two, different formats. The camera makers contributed to this problem with their ditsy idea of "conversion factors." 35mm (24x36mm) was not a shrunken version of 6x9cm, and APS-C is not a shrunken version of 35mm. You only need to worry about what is "equivalent" if you have a bag of legacy lenses that you used to use in 35mm film shooting, IMHO, of course.</p>

<blockquote>

<p>Also, the 35mm-sensor (let's call them that, rather than "full-frame"...</p>

</blockquote>

<p>The sensors in full frame cameras aren't 35mm. They are 24mm x 35.9mm, more or less. 35mm cameras are called that because the width of the film they use is 35mm.</p>

<p>I dont think loss of depth of field is a serious issue for FF (or 35mm format) of the same generation as APS since lower noise at higher ISO so far has more or less compensated this. At equal aperture one lose about 1,5 stops in DOF when going to FF, but you can crank up ISO by 1,5 stops at the same time and increase the f-number by 1,5 stops so you will end up with equal shutter speed.</p>

<p>The APS sensor is more sensitive to aperture diffraction. For FF you really start to lose a lot of contrast at f19. For APS this starts at about 13. So the useable range of apertures are larger for FF.<br>

DOF was a larger problem in the film age. The only way to compensate for smaller apertures in medium format cameras like Hasselblad was to use film with higher ISO. An ISO400 film is a lot worse than a ISO100 film with respect to grain.</p>

<p>The 35mm wide film was called 135. Different brands also had slightly different frames (+-0,2mm or so), then there was half format 18x24mm on the same 135 film! Maybe we should call full frame for just 24x36mm format, but then someone will complaine that its just 24x35,9mm.</p>

<p>This is hopeless! I vote for full frame FF!</p>

<p>This is a beginner's forum, and I don't want to get off into the minutiae of terminiology, but it was brought up SO-</p>

<blockquote>

<p>The sensors in full frame cameras aren't 35mm. They are 24mm x 35.9mm, more or less. 35mm cameras are called that because the width of the film they use is 35mm.</p>

</blockquote>

<p>APS-C isn't a measurement either (though the pictures on the film used to be roughly 15x22mm, and let's round off), it is a FILM TYPE. Once, in the mists of antiquity, it referred to an ill-fated effort, like Rapid loading and Instamati, to create a new film format.</p>

<p>35mm is a FILM TYPE, too (images taken on it with Kleinbildkameras were normally 24x36mm, roughly).German does have a name for the format "Little Picture=Kleinbild" but English speakers have long talked about simply "shooting 35mm," and with little confusion.</p>

<p>Most professionals that <strong><em>I</em> </strong> know of (admittedly limited to the faculty at a professional training program) who deal with both smaller sensor and larger sensor cameras call the larger format "35mm" and the smaller "APS-C" without even using the qualifier "-sensor". Few of these people have shot film in years in either of these sizes.</p>

<p>If anyone wants to continue a long and detailed discussion of this, let's please start a new thread under Casual or somewhere.... and I'll debate this point until the cows come home or the moderator tells us to knock off.....</p>

<p>The reality is that the use of words change by time and at a point one tend to be very odd, using a old word instead of a new modern. This happens all the time whether its right or wrong or we like it or not.</p>

<p>I have been active in this forum since 1998 and before the age of sensors, either 35mm format or 135 format was frequently used. Now the term full frame is by far the most used. Maybe its wrong, but its a hell of a job to bring most else to change.</p>

<p>I apologise for this topic in this thread!</p>

<p>Actually, I think that the thread dove so far down into the minutia is a good thing but only if mentioned:</p>

<p>Peter,</p>

<p>In practical terms, with any modern camera, the differences are, for most photographers, very small. You can make a solid image with either sensor size.<br>

Don't worry so much about sensor size. It's not nearly as important as it may seem.</p>

<p>Since these types of questions tend to digress into divisive debates about the "superiority" of one sensor format over another, I'll just quote from a recent Thom Hogan commentary:</p>

<blockquote>

<p><em>"The FX Lust. </em> I'm going to go out on a limb here and say that most people lusting after FX are using excuses to justify wanting it, not showing real need. Can you <em>really</em> say that you're hitting diffraction, ISO, isolation, or viewfinder brightness limits with DX? Right, most of you can't. Most of you would be better served by the D300's cover-the-frame AF, frankly. DX has advantages, too--cost being a huge one--so don't overlook them." -- <a href="http://www.bythom.com/2009%20Nikon%20News.htm"><em>Thom Hogan, July 13, 2009</em> </a> <br /> </p>

</blockquote>

<p>Be sure to carefully consider how you plan to use your photography before committing either to more or less camera than you actually need.</p>

<p>Peter,</p>

 

<p>If you’re still reading this thread, the practical differences for a photographer are:</p>

 

<ul>

<li>All else being equal, the camera with the larger sensor (film format / <i>etc.</i>) will have

better image quality any way you care to measure it for a variety of reasons based on the laws of

physics.</li>

<li>The same lens mounted on large and small format cameras will have a wider field of view on

the large format, assuming the image circle projected by the lens will fill the whole imaging area.

Practically speaking, this means:

<ul>

<li>Wide-angle full-frame lenses aren't wide-angle on a crop sensor.</li>

<li>Telephoto full-frame lenses become super-telephoto lenses on a crop sensor.</li>

<li>Lenses designed for use only on cameras with a crop sensor can’t be used on a

full-frame camera.</li>

<li>Since image quality degrades the closer you get to the edge of the image circle, and

since a crop sensor camera only uses the center part of the image circle, the crop sensor format is

much more forgiving on lens quality — a lens may have unacceptable corner performance

on a full-frame camera but be just fine on a crop sensor.</li>

<li>Still assuming all else being equal, <strong>the full-frame camera can achieve all the

advantages of a crop sensor by simply cropping the full-frame image to the crop sensor format after

exposure.</strong></li>

</ul>

<li>A larger format is capable of achieving a narrower depth of field than a smaller one. The larger

format can still achieve the same wide depth of field with at least the same quality results as the

small by using a smaller aperture and higher ISO, and better results by lengthening the shutter

speed instead of raising the ISO.</li>

<li>Because of the superior image quality of a larger format, images can be more aggressively

cropped and / or enlarged while maintaining printing standards with a large format than a small

one.</li>

</ul>

 

<p>And, as you hinted, the larger format cameras are generally built to higher standards with more

features, as well.</p>

 

<p>You’ll notice that I at least tried to pretend that it’s a matter of comparing formats

<em>in general,</em> not in the absolute case of the two popular DSLR formats. Everything I

wrote applies equally well to a comparison of a full-frame DSLR and medium format digital, as it

does to 4x5 film <i>v</i> 8x10 film, and so on.</p>

 

<p>Oh — and that “all else being equal” is pretty important. It’s pretty well established that digital objectively compares quite favorably with the next larger film format size; that is, APS-C digital is as good as or better than full-frame film, full-frame digital is comparable to medium format film, medium format digital is starting to encroach on 4x5 film, <i>etc.</i> We’ve also seen enough improvements in digital that the latest generation APS-C DSLRs are a serious alternative to first-generation full-frame DSLRs in many ways. BUT… you’ll probably get better results shooting telephoto with a modern APS-C camera than cropping a modern full-frame camera. Perhaps not dramatically so, but birders are still better off going for the smaller format, at least for the time being.</p>

 

<p>Cheers,</p>

 

<p>b&</p>

<p>If you get an FX sensor, you need lenses with greater <em>covering power</em> to produce images that are sharp across the diagonal of that larger sensor. They are harder to design, so you'll likely have tradeoffs in speed, zoom length, size, weight, and/or cost. That's it in a nutshell.<br>

As to whether the tradeoffs are worth the benefits of full frame, I'm in no position to argue with Thom Hogan.</p>

<blockquote>

<p>Still assuming all else being equal, <strong>the full-frame camera can achieve all the advantages of a crop sensor by simply cropping the full-frame image to the crop sensor format after exposure.</strong></p>

</blockquote>

<p>There's some truth to this especially if you're shooting a 5D MkII or Sony A900 with >20mp but if you're shooting a 5D MkI or Nikon D700 you're going to end up with fewer pixels than if you shot one of the current batch of 14-15mp APS-C bodies.</p>

<p>The usefulness of the lenses avilable. There are a huge legacy of lenses for FF since 50 years or so. Prime lenses like 20/2,8, 24/2,8, 28/2,8 etc have a very different impact on FF than in DX. Fast wide angle zooms are still absent in DX from the camera manufactures. Its moving forward with DX but quite slow in this area. Fast telezoom with corresponding focal lengths are only made by third party manufactures.</p>

<p>The ongoing increase of pixel count in DX call for better lenses, or will the additional pixels be in the air. I am sure they can make this lenses ( Olympus made a few for 3/4 format and Nikon just announced the DX 35/1,8) but they seems to put their effort into FF lenses instead.</p>

<p>Hi Guys, Many thanks for your replies - albeit some are a bit over my head. That being said the consensus of your opinions have answered what I really wanted to know - I am a pure novice using a D60 and as a beginner finding this little camera fantastic. I am still learning but at the same time I am beginning to aquire lenses. Namely Nikon 18-200 Vr, Nikon 50mm 1.4G, Sigma 10-20mm Hsm and a Sigma 150-500mm. Now, whilst I have every thing I need at present, looking to the future, when I retire in a couple of years time, I shall have (hopefully) gained more experience and having more time??? shall probably upgrade the camera body at that point. The reason for asking therefore was whether I would really benefit from a FF camera as opposed to say the D300. From what I understand I would never really use a FF to it's optimum use and most of the lenses would not really be matched to a FF. I think the D300 would more than satisfy my needs and save me having to re-invest in different lenses. My thanks once again I appreciate your time and trouble. Pete.</p>

<p>First of all if you go FF you are going to have to replace at least two of your lenses. The 18-200 and 10-20 are for DX only.<br /> <br /> You might check out Thom Hogan's take on FF vs DX, just google it.</p>

<p>In a couple of years, the situation may change regarding both pricing and technology.<br>

A nice thing with Nikon FF, is that your DX lenses still can be used on your FF body with a DX frame in the viewfinder, so you will know what you capture.</p>

<p>Thanks for your comments guys. Very valid point about the situation changing in two years Bengt, Nikon will have probably replaced the D300 by then, which means the D300 should come down in price - and that would suit me just fine!!! Thanks to you all. Pete.</p>