Is DX superior to FX?

sevencrossing

donaldjose. The thing is that if you are cropping 1/3 of your photo away, you might be better off with DX. The 7100 has 24mp in the crop area and the d800

This idea has been quoted many times on NRF but I have yet to seem any real life comparisons.
I would guess, as the ISO is increased, any advantage might start to disappear, as high ISO noise seems to be related to pixel density

Has any one with a D7100 and a D800 done any tests ?

manhattanboy

On wednesday I am shooting Brendita. I plan to shoot half the shots with the d7100 + 35 art and the other half with the d800. + 50 art. Should be a fair test and Brendita is the prettiest little blonde.

I am eagerly awaiting the results
On Wednesday, I will be shooting myself for not having your job that day LOL.

In all seriousness, there are differences in the way pictures look shot with different lenses even if they give the "same" perspective (e.g. 35 versus 50 in this case). See http://www.sebstudios.net/for-photographers/portrait-lens-50mm-85mm/ for example.
I personally do not like to go any lower than 50mm on DX, but indoors you are basically forced to unless you want pieces of a person LOL.

donaldejose

Should be a fair test. Another option might be to try the Sigma Art 18-35 f1.8 on the D7100.

Golf007sd

One can use a variety of different lenses in taking a single image and maintain the same composition and framing. What will not be the same is the manner in which the back ground looks. Hence, with a wide angle lens, you will have far more of the background in the image vs if taken with a longer lens...be it a prime or a telephoto. The "compression" of the background or lack of it, will, IMHO, have profound visual effect.

sevencrossing

I think the idea is to see any difference between the image from a D800 cropped to DX
and a full frame dx image from a D7100 using the same lens

donaldejose

Not the same lens, equivalent lenses. 24mp vs. 16mp sensor area's compared. Depending upon the amount of light available, or supplied, there also may be an IQ difference if shot at high ISO (like 3200 or 6400) but likely no significant IQ differences if shot below 400 ISO. Although what photo can be focused on which camera will all depend upon the point of focus. The head/eyes may not be on the edge of the frame in all poses. Thus, some poses may well be able to be framed and focused full frame with the D800 50mm f1.4 Art while others will require the D7100 35mm f1.4 Art.

WestEndBoy

Incorrect answer. Sometimes DX is better. When you want a smaller lighter body with lighter lenses, when you want to get more reach from your existing telephoto lens, when you want to have more working distance with your macro lens, when you want to spend less money, etc DX is better. When you want the shallowest DOF or the highest clean ISO or the best image quality for huge enlargements FX is better. With the advent of the 24mp DX sensor in the latest generation DX bodies I think FX has lost some of the advantage it had in the D3/D700 generation. DX is just closing the gap for all reasonable size printing.

Hmmm.....I do agree with you as it applies to many users, perhaps most. However, for me:

Cost - not an issue.
Weight - not an issue.
Reach on telephoto lenses - this is a "cost and weight" argument disguised as a "reach" argument, reach being an argument that nobody has been able to define to my satisfaction, so I am not buying it. I will concede that their may be a "pixel density" advantage, but only on a top grade FX lens. I doubt their is a DX lens that can exploit this "pixel density" advantage. Besides, it is an ephemeral advantage. The next D800 upgrade (or so) will negate that advantage and then there will be few FX lenses that can exploit further megapixels by much. I am not going to make a decision on format for an ephemeral advantage on one of a dozen factors.

WestEndBoy

On wednesday I am shooting Brendita. I plan to shoot half the shots with the d7100 + 35 art and the other half with the d800. + 50 art. Should be a fair test and Brendita is the prettiest little blonde.

So far I have agreed with everything you have said Pitchblack and I find the AF coverage issue equally frustrating.

However, with the above comparison I caution you that you may be comparing the two lenses, not formats or cameras. I suspect that most of the differences will due to the comparative qualities of the lenses.

You will also need to stop the FX lens down to about F 2.5 to 2.8 for the comparison to be valid, as the depth of field will be similar to DX. You might even have to stop it down even more due to the focal length difference, but I am too lazy to go to www.tawbaware.com to figure it out. This is one reason why I find the latest Sigma F/1.8 DX a bit of a fraud.

And there is one thing that I have been thinking about relating to the AF coverage issue. I know that you (and I) love to shoot our 85mm 1.4Gs wide open. You and I both are also concerned about sharpness at 1.4 (I will buy the 58mm 1.4 despite the softness at 1.4, but will revert to the 85 when it concerns me). However, if the model's eye is not in the centre of the frame, but on the side somewhere, then we are losing sharpness because even the 85 is softer on the side at 1.4. The question is, "how much? If we shoot the model's eye in the middle and then crop to get the same composition that you have previously provided, we will lose sharpness because we are losing megapixels and thus resolution. But, "how much?"

So even if the D800 could autofocus across 100% of the frame, you might not actually be better off with it from a sharpness perspective. Or we might be. Or the difference will be so small as not to matter.

Hmmmm..............

manhattanboy

Cost - not an issue.
Weight - not an issue.
Reach on telephoto lenses - this is a "cost and weight" argument disguised as a "reach" argument, reach being an argument that nobody has been able to define to my satisfaction, so I am not buying it. I will concede that their may be a "pixel density" advantage, but only on a top grade FX lens.

This is why I shoot the 7100 with an FX lens. You sound like you get up close with your shots. What if you were 1000 feet away? Yes, you can in camera crop the D800 and get to the sweet spot of a lens. But you can also in camera crop the 7100 to get to an even sweeter spot of the lens for an effect doubling of the 35mm focal length. This is why a crop camera comes in so handy. If the shooting lets me, then I agree FF all-the-way and my current set up is a dual one with FF for <200mm and crop for >300mm. But, the DR on the 7100 is very good, especially corrected in post, and in shooting distant objects with a super sharp FX lens, the 7100 is practically unbeatable at this point (the mythical 9300 not withstanding).

I think the idea is to see [ ]

...to see what the prettiest little blonde, Brendita, will...I lost my train of thought... :-))

PB_PM

n/m

sevencrossing

WestEndBoy reach being an argument that nobody has been able to define to my satisfaction, so I am not buying it. ......


+100
Fx - 24mm x 36 mm defined by Oskar Barnack a 100 years ago in 1913.
and still going strong

snakebunk

@WestEndBoy: People use the word reach differently. But what I find important is that a camera with high pixel density enables you to crop more than a camera with low pixel density. That is an important aspect for me as a bird photographer. It doesn't really have anything to do with FX or DX other than DX cameras tend to have a higher pixel density than FX cameras.

I agree that FX is a very usable size of a sensor, at least with the current technology. If/when they can make cameras with larger sensors that have a high enough pixel density and a reasonable price, they will be more interesting. I look forward to mirrorless and manageable medium format cameras with a really high pixel density (have to buy a new computer before that though).

Currently the D800 is the best choice for me. I can shoot birds pretty far away with a good enough number of pixels and I can shoot a bird much closer, or a big flying bird, without the need to use a zoom lense.

To state that one sensor size is best is always wrong. It is as silly as saying that a house with two floors is better than a house with one floor.

sevencrossing

@PitchBlack Many thanks, we look forward to your results

DaveyJ

Very Lovely photo!!

Tradewind35

May I add a different take on this debate, As an almost total illiterate on digital photography I was open minded about DX v Fx but lean (unintelligently) towards FX as all my photography has been on 35mm film with full coverage of good mf Nikkors. So when I look at what is available from Nikon - love look and feel of Df - natural choice for me - but huge cost. For far less could get a D7100 and half way would be a D610. Picked these up in shop and had a good play with them. Major turn off for me on the D7100 are those feeble little flaps that cover the sockets on the body - when I grab the body half the time the covers get pushed open - feels naff. Much better fit and finish on the D610 - for me worth the extra grand or so untilI get a Df maybe and I don't feel that I am accepting any compromises by using FX glass on a DX body. So as an illiterate, FX gets my vote, think I can live with shallower dof.

DaveyJ

@Tradewind35: Something is wrong with the D7100 camera you are picking up to push covers open accidentally. I've owned a couple of D7000s and the D7100 and never had this happen. You also must be immune to having all the focus grids on the inside of the camera. The D610 is very little more than a D7100 with an FX sensor.

spraynpray

What DaveyJ said or you must be handling your D7100 in an unusual or non-dexterous way. The tiny cover under the little finger of my right hand on my D7000 is occasionally a nuisance, but my D7100 has zero issues.

WestEndBoy

Maybe Tradewind just has bigger hands.......

DaveyJ

My son and grandson use my D7100 a lot. They have larger than average hands. I have seen a NUMBER of Nikon cameras (my D300 is an example) which have issues with the flappy doors that pretty much now is in the black duct tape fix required or get them replaced by Nikon USA at our cost.

Ironheart

Gaffers tape. Don't leave home without it.

Photobug

@All - I kept up with his forum until the end of April when we went on vacation and when I got back there were at least 40 messages. Then 2 weeks later another vacation and I gave up reading this forum. I just spent the last 1+ hours reading all the unread messages. This was very educational for me and a great discussion on FX and DX. To all that contributed thank you. This is what makes NRF outstanding.

Now I understand why @PitchBlack is so frustrated about the AF coverage issue and wish I had understood the physics of the mirror and read this forum before writing my first impression on the D750. Never to old to learn something.

Someone is going to ask why did you spend the time to read this forum and the answer is simple. I am contemplating the move to FX and after reading this forum I decided to keep my D7100 and sell the 17-55mm DX lens.

Any way I just wanted to leave this message thanking all the contributors and laughing how it ended...with a reference to Gaffers Tape. LoL I am sure newcomers to NRF will find this discussion on DX & FX Superiority to be very educational.

Terry7732

I have followed this thread for some time and there have been some very forthright comments on both sides. Some DX users probably feel that they have to perpetually defend themselves while some FX users appear to look down their noses at the DX users. Despite the strong views on both sides there appears to be very little evidence to back up these views, and by this I mean real world evidence. Everyone knows that the difference between FX and DX photographs is easily measured in the lab, but photography is about photographs, not lab tests. At this point I should mention that I use a D610 and a D7100, each for different situations. If these bodies are bought as a kit then the D610 will produce better results because it normally comes with a better kit lens, and this is the crux of the matter. It is the lens that is responsible for the better result not the body. To test this out I carried out the following experiment.
I took identical photographs using a 24-70 f2.8 with the range being set at 40mm for the D7100 and 60mm for the D610. I then printed the two photographs on A4 paper and showed them to twenty different people. Fifteen said they could not tell the difference and of the other five three preferred the D610 version and two the D7100. This proved to me conclusively that for practical purposes there was no difference in the image quality from the two cameras.

WestEndBoy

I am not sure that proves anything, as the limiting factor on a test like that will be the lens. For a test that illustrates the difference between the formats, try a low light shot and then try a shot with high dynamic range.

I have all three formats (CX, DX and FX). My Coolpix A produces some great images when the light is good because the lens is better than most FX lenses. However, under adverse conditions the benefits of FX are obvious and not trivial.

Terry7732

You have just proved my point. The only way to conduct a meaningful comparison is to use the same lens on each body. Incidentally, I hardly think the lens in this case was a limiting factor being one of Nikon's premier lenses, if anything it would have shown up any shortcomings of either body. I would also reiterate that this experiment was to demonstrate the results in normal circumstances, not under abnormal conditions. The average photographer does not care about "adverse conditions" or "dynamic ranges" all he wants is a good photograph. Unusual circumstances, as you rightly point out, need to be catered for by a different approach but this experiment applies to the majority of situations where the photographer just wants a good photograph.

WestEndBoy

You have just proved my point. The only way to conduct a meaningful comparison is to use the same lens on each body. Incidentally, I hardly think the lens in this case was a limiting factor being one of Nikon's premier lenses, if anything it would have shown up any shortcomings of either body. I would also reiterate that this experiment was to demonstrate the results in normal circumstances, not under abnormal conditions. The average photographer does not care about "adverse conditions" or "dynamic ranges" all he wants is a good photograph. Unusual circumstances, as you rightly point out, need to be catered for by a different approach but this experiment applies to the majority of situations where the photographer just wants a good photograph.

If you look at my Flickr link in my thread, a solid 25% of the images would be noticably inferior with DX. I am often wishing I had better low light performance when shooting and more dynamic range in post. Not to mention that I am often shooting at 1.4 in FX. Shooting at 1.4 in DX gives a similar depth of field as 2.8 in FX.

It seems that abnormal conditions are not that abnormal.

Of course if you are shooting snapshots, which is what most people do (to your point), then I would be the first to recomend a DX camera and perhaps even a superzoom kit lens.

However, I do agree that when the stars align and there are no adverse conditions to deal with and there are enough megapixels available, lenses are the determining factor.