Is DX superior to FX?

TaoTeJared

@TTJ, "That is actually the same difference. The inner part of the image is projected by the inner part of the lens. "

No, I claim that is incorrect. All parts of the FOV use all parts of the lens.

I'm scratching my head. I'm wondering if it is just a terminology is not matching up.
A 35mm lens on DX only has the FOV of a 50mm as the rest is cropped off.

35mm lens FOV
FX (in Deg) || DX
Horizontal 54.4 || Horizontal 37.0
Vertical 37.8 || Vertical 25.1
Diagonal 63.4 || Diagonal 43.8



Is that what you are referring too?

sevencrossing

Cost matters, because Iq ultimately requires the best equipment for the job, and if the same quality is cheaper, you can afford more of it.

Thanks GreenFlash for bringing a big smile to my face

May I suggest you look at the early works of AA ( February 20, 1902 – April 22, 1984)

He mostly used one camera and one lens; as did Henri Cartier-Bresson (August 22, 1908 – August 3, 2004)

TaoTeJared

... (We have all tried to make fire with a magnifying glass. To do it we want the light to be focused on the smallest point. Hence more heat at that point.
That's why I was thinking that If the light from the same fov passes through a lens of comparable diameter, but is bent to hit a smaller sensor, the light intensity on the sensor will be greater. So that would at least somewhat offset the reputed low light advantage of fx format cameras.

No, no, no, no, no. Incorrect assumption by miss applying different applications for what is happening.

... As was pointed out, the lens has to be awfully accurate to deal with the smaller pixels. But if the lenses are up to the job, maybe we have come to a time when DX really is equal or better.
So I pose the above referenced new 18-35 mm 1.8 Sigma and the 11-16 2.8mm Tokina as examples of high quality fx sized lenses with a dx sized output, that have comparable ratings to the best fx lenses out there.

Incorrect rationalization. One cherry picked DX lens that is sharper than another cherry picked FX lens, has absolutely zero relationship on the performance of a camera's sensor. Most DX (or other format) lenses are actually full frame lenses that have the outside edge "trimmed off" in the design phase. Again DX, uses only the "best part" of a FX lens. Sharpness tests include the whole lens. So if FX uses more of extreme sides of the lens, it makes perfect since that it would score slightly lower.

... But also the question I posed, if you shoot at a reduced number of pixels, will each pixel be larger and hence receive more light and be more accurate? (and allow lower ISO's and faster shutter speeds at lower light levels?

No. Read up on the "Exposure Triangle".

GreenFlash - You are making incorrect assumptions how light and what technology does. Honestly I gave up as you are asking questions that cross so many disciplines that volumes of books are written on each and most questions have been answered over 100 years ago. Digital has not changed the laws of physics - it is all the same. You have some understanding of how things work, but you are making incorrect leaps to the connections of where you have some missing information how everything acts together and is just a bit off. Reading more on exposure and the basics of photography will fill in the gaps quite quickly.

In a way, the discussion sort of explains the D9300. If fx were superior in all cases, it could be argued that the D 9300 would be irrelevant. But clearly, it is not.

There is no mystery here - it exists because of it's price point. Every other reason is far, far behind that for why it exists.

ads

I think another factor is what you are using your shots for. If you just look at them on a computer screen then the difference between DX and FX shots wont be as apparent compared to if you are doing 40"x30" prints. I wasn't unhappy with my big DX prints, but I'm stoked with the FX ones.

So to in answer to "just about reached the point where half frame DSLR's are for most purposes, superior to full frame" it depends on what you mean by "most purposes"

Msmoto

In my early days, there was a reason we shot 8" x 10" Ektachrome vs. 4" x 5" Ektachrome. The client was convinced the size matters. And, IMO, the area of capture on any medium is important, no matter how high the quality of the sensor… bigger is better.

Having said that, I agree, some eye grabbing images can be shot on crop sensor. But, other than file size I cannot see an advantage of cropping the sensor size if it is possible to shoot with a full frame.

heartyfisher

@GreenFlash is right though about 1 thing.. every part of the lens effects every pixel.. unless the aperture is closed down.

donaldejose

"Bigger is Better" or "Bigger is Always Better" Is that true for sex and photography?

Well, consider enlargements. When you print at 24 inches by 36 inches you will always be enlarging the area of light captured by a DX sensor more than you are enlarging the area of light captured by an FX sensor. It should be always better to enlarge less so FX should be better than DX. But what if you have a 24mp DX sensor compared to a 12mp FX sensor? Then would the added detail captured by the higher megapixel DX sensor yield a better 24 by 36 inch print than the same size print from the 12 mp FX sensor? I don't know.

Lets compare the IQ obtained from a 24mp DX D7100 to the IQ obtained from a 12mp FX D3. Is bigger always better? I don't think so. DxOMark rates the D7100 sensor at 83 while it rates the D3 sensor at 81. Could you see any difference in the same image shot at all the same settings on both cameras and both enlarged to 24 x 36 inches? I don't know. Maybe someone here knows the answer.

However, it is probably a bit academic for most of us who will rarely print that large and at sizes like 8x10 where I doubt you could see any difference.

I do tend to believe in the phase "bigger is better."

I should also say I would always chose full frame, unless weight was important, simply because I come from a background in 35mm film and FX focal lengths "make sense" to me (I understand what each will look like on film or FX sensor) while DX focal lengths cause me to pause to calculate just what DX size I want for the job in 35mm film equivalents. What the heck is that 18mm? Is it really equivalent to 24mm or 28mm or 35mm? What is 11mm in DX? What is 16mm in DX? etc. For me, FX is so much easier to understand.

sevencrossing

"
Lets compare the IQ obtained from a 24mp DX D7100 to the IQ obtained from a 12mp FX D3. Is bigger always better? .

As a rule of thumb . The IQ of current generation of Dx sensors, are close to the IQ of the previous generation of Fx sensors

In this case, I think it would depend on the ISO value; at high ISO values, I suspect the D3 would win

FX is so much easier to understand.
+1

Particular as some manufacture,s list the focal length of their DX lenses as the full frame "equivalent"

GreenFlash

Thanks guys.

michael66

I'm scratching my head. I'm wondering if it is just a terminology is not matching up.
A 35mm lens on DX only has the FOV of a 50mm as the rest is cropped off.

Great visual.

Two questions.

Wouldn't the DOF also be the same, as it is a function of the lens and not of the view-finder or sensor?

What would the quality of the image taken with an FX camera be when compared to the image taken with a DX camera, if the FX's image were just that portion of the view captured by the DX camera? I assume that the quality would change as you used different cameras, so consider a D800 ( 36MP ) against a D7100 ( 24MP ).

michael66

I should also say I would always chose full frame, unless weight was important, simply because I come from a background in 35mm film and FX focal lengths "make sense" to me (I understand what each will look like on film or FX sensor) while DX focal lengths cause me to pause to calculate just what DX size I want for the job in 35mm film equivalents. What the heck is that 18mm? Is it really equivalent to 24mm or 28mm or 35mm? What is 11mm in DX? What is 16mm in DX? etc. For me, FX is so much easier to understand.

If I could afford it, I would have a D4. I can't, so I have a D7100. And with the money I saved, I am buying FX lenses for when I can afford an FX body. As for what 'xx'mm that lens is, I am using mostly zooms; 12-24, 24-70 & 70-200, and tend to move the zoom dial as opposed to my feet. This seems to be far easier than training and re-training my eyes to FOV as it relates to a given 'xx'mm.

spraynpray

In my early days, there was a reason we shot 8" x 10" Ektachrome vs. 4" x 5" Ektachrome. The client was convinced the size matters. And, IMO, the area of capture on any medium is important, no matter how high the quality of the sensor… bigger is better.

Having said that, I agree, some eye grabbing images can be shot on crop sensor. But, other than file size I cannot see an advantage of cropping the sensor size if it is possible to shoot with a full frame.

...Except for those medium format digital cameras eh? Your FX's are much better than them of course (as read on a thread here). /:)

I have to say that some of the worst or at least most average images I have seen have been shot on the best gear. The phrase 'all the gear, no idea' was invented for a reason.

Coincidentally, the final round of my clubs yearly competition was last night - DX cameras got the top 5 slots.

I think that in comparison to DX, FX shooters get the prize for most smug attitudes though... ) )

PB_PM

...Except for those medium format digital cameras eh? Your FX's are much better than them of course (as read on a thread here). /:)

Until recently yes. Medium format was very good at base ISO, but terrible above ISO400, due to noise and loss of dynamic range. Current generation medium format bodies that have adopted CMOS sensors are on par, or on par with the D4. Then again, they cost $30,000+ more. That's a big leap compared to the price difference between the D7100 and the D610. The fact that a camera that costs $6k can basically match a camera (noise wise) that cost $40k says a lot.

Frankly I think we need to get passed the whole DX vs FX battle, because there is no battle. Each has a place, and in the hands of a good photographer both are excellent tools. Both have advantages and disadvantages, depending on a given users shooting style.

I think that in comparison to DX, FX shooters get the prize for most smug attitudes though...

How does saying something like that make you any less smug? :-?

manhattanboy

would the added detail captured by the higher megapixel DX sensor yield a better 24 by 36 inch print than the same size print from the 12 mp FX sensor? I don't know.

It depends, but for many situations the answer is yes. Beating a dead horse, DX trumps FX in distance shooting.
If I had to take a picture of X far away and only had a good 200 mm lens, then the DX would allow more pixels on the actual object and is superior to massive cropping of a full frame image. This is the "reach" advantage and the major benefit of DX over FX.

The above situation does not always hold if the lens is poor, however. Also beating a dead horse, because the pixels are larger in a full frame camera (generally), the lenses do not need to be as good to get better IQ as there is more slop allowed in the focusing for each pixel. The current Nikon DX sensors are very good IF (and that is a big IF) you have a lens that can properly resolve the image. Thus, for a given lens, you can crop more in an FX frame because the image resolution is relatively buffered by the slop allowed in the focus. Cropping a DX frame is difficult if you are going to enlarge it as the lens needs to produce a very sharp image or the focus will seem soft. In practice, when shot with Pro lenses I can crop FF images up to 200% before significant pixelation occurs. DX depends, with a crappy lens it is only 100% (if that LOL); with a good lens you may be able to crop more than 100%.

ISO and noise are another topic altogether, but suffice it to say that the larger capture area of the pixels in FX allow for less noise than a DX (and PSA: there is a whole thread right now on the FF sony A7S with its low light capabilities). Unfortunately the tiny pixels in the current Nikon DX sensors mean that even at ISO 400 there is noticeable noise in 100% crops.

spraynpray

...Except for those medium format digital cameras eh? Your FX's are much better than them of course (as read on a thread here). /:)

Until recently yes. Medium format was very good at base ISO, but terrible above ISO400, due to noise and loss of dynamic range. Current generation medium format bodies that have adopted CMOS sensors are on par, or on par with the D4. Then again, they cost $30,000+ more. That's a big leap compared to the price difference between the D7100 and the D610. The fact that a camera that costs $6k can basically match a camera (noise wise) that cost $40k says a lot.

Frankly I think we need to get passed the whole DX vs FX battle, because there is no battle. Each has a place, and in the hands of a good photographer both are excellent tools. Both have advantages and disadvantages, depending on a given users shooting style.

I think that in comparison to DX, FX shooters get the prize for most smug attitudes though...

How does saying something like that make you any less smug? :-?

I can't be smug, I don't have any FX or RRS or holy trinity - nothing to see here in the cheap seats!

Msmoto

This discussion reminds me of what I was told about 50 years ago by Gerhard Bakker…."They tried so hard to be different they forgot to be good." And, in some ways our preoccupation with the gear gets us sidetracked.

An example… this weekend I was shooting BIF, and in a venue I had no idea how it would be set up until I was there…. Well, all my fancy gear got me very few images as I could not get the camera set to grab the rapidly moving, variable subject….. I finally tried AF-C, with 3-D tracking, and maybe this is what works. I am going to see how this goes with BIF near the ocean in a week or so.

I think I like the full sensor as I am a bit rusty and not able to track the subject as well as I used to. Also, my objective on this first shoot at the Carolina Raptor Center was to learn about the venue and when I return in the fall, I think I might get some good shots.

If I had shot this weekend on my D90, I am of the opinion the difference in the results would not be noticeable in the sizes on Flickr. Maybe if I printed to about 24" x 36" the different size would mean something….but the overall image requires a lot more than simply using a pro level camera, crop sensor or full.

PB_PM

Bit of advice, forget about 3D tracking with BIF, unless they are against blue sky.

snakebunk

@manhattanboy: Well put!


In the context of shooting with a 500 mm tele lense:

When I only had my D300s I felt that the pixel density was a limiting factor. With the D800 I feel that the lense is the limiting factor (ignoring myself for now). If I upgrade to a better lense I may be looking at higher density DX cameras again.

Generally I like FX because it is a larger sensor and I can fit larger objects on it (using the same lense and shooting distance). The benefit of DX is that you can put a lot of pixels on the object.

PB_PM

I can't be smug, I don't have any FX or RRS or holy trinity - nothing to see here in the cheap seats!

You don't need to have FX or fancy gear to make a smug statement about others. Statements like the one you made are needless and adds nothing constructive to the discussion.

manhattanboy

Generally I like FX because it is a larger sensor and I can fit larger objects on it (using the same lense and shooting distance). The benefit of DX is that you can put a lot of pixels on the object.

You may like the 1.3 crop modes in the 7100 (and presumably 7200 and 9300). I am not sure how often you use it for the D800 (which would likely be a surrogate gauge for your realistic benefit of it in the 7100, etc). I find it gives you that extra width when you need it and the extra reach when you don't. It's one of my favorite features of the 7100.

You don't need to have FX or fancy gear to make a smug statement about others. Statements like the one you made are needless and adds nothing constructive to the discussion.

I think he was just joking and meant no harm, but I could be wrong LOL.
Most everyone here on NF is relatively nice and makes reading these threads enjoyable, not to mention educational. At least that's the perception I like to fool myself into believing )

PB_PM

I kind of thought the same a first, and that might be the case. I thought I'd throw that out there anyway, since it's a theme I see each time a DX vs FX debate comes up. Meaning there is a ongoing accusation by some DX users that FX users are smug and arrogant simply by virtue of having expensive gear. While that may be the case for some, such blanket statements are unfair to most who are anything but.

tcole1983

I can't be smug, I don't have any FX or RRS or holy trinity - nothing to see here in the cheap seats!

You don't need to have FX or fancy gear to make a smug statement about others. Statements like the one you made are needless and adds nothing constructive to the discussion.

I thought it was funny and I am right there with spray...the fx equivalent of my 17-55 keeps me away from fx. $950 vs $1800. And losing range. I would probably also want the 70-200 which isn't going to happen for me anytime soon.

proudgeek

I don't think any harm was meant by it. I certainly wasn't offended and I shoot with a D800.

PB_PM

It's not that I found it offensive, and I don't really think @spraynpray meant it as such. I simply didn't think it added anything positive to the discussion.

Let's just leave it at that, and carry on with the topic at hand. Thanks!

TaoTeJared

I'm scratching my head. I'm wondering if it is just a terminology is not matching up.
A 35mm lens on DX only has the FOV of a 50mm as the rest is cropped off.

Great visual.

Two questions.

Wouldn't the DOF also be the same, as it is a function of the lens and not of the view-finder or sensor?

What would the quality of the image taken with an FX camera be when compared to the image taken with a DX camera, if the FX's image were just that portion of the view captured by the DX camera? I assume that the quality would change as you used different cameras, so consider a D800 ( 36MP ) against a D7100 ( 24MP ).

Nope - the DOF becomes wider (increases/deeper) as the crop factor increases. You can play with the Calculations here

The IQ of DX vs FX Can be equal - it also can be very different. At low ISOs (under iso 400) it would be very close. As ISOs rise the difference becomes very apparent where FX is much better.