Bird Photography: Dx vs Fx

[Grant Atkinson]

This is an interesting thread for sure, and the topic can become pretty involved. First up, there is not really much point directly comparing the Canon 7D with the Nikon D3s when the latter costs 2x or 3x as much. Better to compare the 7D sensor with that of the Nikon D7000, and the D3s with that of the Canon 1Dmk4. And this has been done, extensively, by several very capable photographers and with results published on the internet. There are also scientists who have analyzed the sensor performance characteristics. It would seem that the major manufacturers are possessed of similar level of technology to put into their sensors though, and the biggest differences that we are seeing in image quality are coming from the different sizes in these pixels. Broadly speaking, any of the Canon or Nikon dslrs of similar cost and of similar age in technology terms, should have similar image quality characteristics if one compares similarly sized pitches.
With this in mind it might also make most sense to compare the Canon 5Dmk2 and the Nikon D3X. I have limited experience with the D3X but from what I have seen it is in fact fairly similar to the 5Dmk2 in terms of IQ and noise characteristics.
With the 1Dmk4 and the D3S, the two companies have taken different routes with similar technology levels, with their sensors. The 1Dmk4 has pixel pitch of 5.7microns, the D3S has pixel pitch of 8.45microns. The Canon approach results in the possibility of cropping to bigger subject size, regardless of the crop factor, from the same position using the same lens as more of the smaller pixels fit into the subject. Seemingly the smaller pixels trade-off is noise as the bigger pixels of the D3S give cleaner-looking files, although at a smaller subject size.
Morkel contends with his excellent malachite kingfisher image that the quality gain of the 8.45micron pixels is of such magnitude that the lower resolution of the cropped files becomes less important.
The quality of the cropped image he has attached is very impressive. However that may be I am also sure that as good as that picture is, there will be applications where it will not meet resolution requirements. Many stock agencies have certain resolutions as a certain requirement and there are certainly other times when higher resolution is a pre-requisite.
To also partly answer Jeff's question, I use the 1Dmk4, 1Dmk3 and 7D extensively. I have also read up on pixel pitch, and sensor performance wherever I can find insightful information, and much of the more scientific literature would tend to point to similar performance from similar aged sensors, but of course, one needs to take into account subject size. In this regard I would have to say that comparing the 1Dmk4 to the 7D is again a little like comparing the D3s to the 1Dmk4, two cameras with very different pixel pitches. In this case the 7D has pixels of 4.3 microns, compared to the 5.7 microns of the Mk4. In order to get the same subject size with the mk4, you have to either get physically closer to your subject, or use a longer focal length. If you do that then the image quality of the Mk4 is significantly superior to that of the 7D. However, if you cannot get closer to your subject, then you need to either fit a 1.4x converter to the Mk4 (and I have done this with the 300f.8IS) which ends up giving you results in terms of image quality very, very similar to that of the 7d, at roughly the same subject size. Or, you could take the approach Morkel is showing here, and crop the 1Dmk4 images deeply until they match the subject size of the 7D image. I have not done this yet, but do have images taken for testing purposes from the 7D, 1Dmk4, 5Dmk2, Nikon D3S and the D7000, and if time permits, I will see if I can compare the files properly, and share some real-world results here, but this stuff does take tons of time, and tons of people are taking great shots everyday with dslrs with large pixels, and small pixels, so I try not to get too caught up in it.
cheers
Grant

[Morkel Erasmus]

This is an interesting thread for sure, and the topic can become pretty involved. First up, there is not really much point directly comparing the Canon 7D with the Nikon D3s when the latter costs 2x or 3x as much. Better to compare the 7D sensor with that of the Nikon D7000, and the D3s with that of the Canon 1Dmk4. And this has been done, extensively, by several very capable photographers and with results published on the internet...but this stuff does take tons of time, and tons of people are taking great shots everyday with dslrs with large pixels, and small pixels, so I try not to get too caught up in it.

I knew you were bound to find this thread, my friend

First off, I have seen some of the tests and comparisons on the web, and I know you know that I know it's not "fair" to compare the D3s and 7D, but that is what I shot with and the transition I made, and I thought it related well to what Leon was asking in his OP.
He needs to make a decision between staying with the DX format or moving to the FX format. You cannot make this decision without "unfairly" comparing the totally different camera bodies with each other. I just threw a cog into the mix where I switched sensor format and camera brand .

I totally agree with your last statement, by the way!

[Grant Atkinson]

Hey there Morkel
I have been following the thread and was trying to stay out , this could be a time-consuming one. Am also aware of what you were posting with regard to Leon, but I also know how easy these things get picked up and taken the wrong way, not by me or you in terms of the 7D and D3s. I would actually prefer to hand it over to Roger from BPN to answer.
Anyway, I have actually gathered all the test images I shot and have a sequence of the same subject taken with the same lens, same position and 3 different camera bodies, the 5Dmk2, the 7D and the 1Dmk4 and I will see if I can get around to cropping them to match subject size, and other useful comparisons and then posting it online...but I would rather be shooting

[Francois Retief]

Grant - it would be great if you could share the comparisons with us ! I was thinking of upgrading from a 7D to 1Dmk4 ...

[swainsons]

Nice scientific response, thanks Grant. I have always wanted to do a "tennis ball" test at say 10m with a Dx and Fx body and then compare the results. Maybe Morkel can do that for us as he owns both bodies then we will have a C and a N comparison.

Greetings...

[Grant Atkinson]

I will see if I can get together some comparisons in different conditions and post for readers to make their own conclusions, and I will concentrate on the 7D and 1Dmk4. Just need a few days for that one. Morkel, maybe you can do similar for the D3s and the D7000....
Cheers
Grant

[Morkel Erasmus]

I will see if I can get together some comparisons in different conditions and post for readers to make their own conclusions, and I will concentrate on the 7D and 1Dmk4. Just need a few days for that one. Morkel, maybe you can do similar for the D3s and the D7000....
Cheers
Grant

Nice scientific response, thanks Grant. I have always wanted to do a "tennis ball" test at say 10m with a Dx and Fx body and then compare the results. Maybe Morkel can do that for us as he owns both bodies then we will have a C and a N comparison.

Greetings...

Just on my way to the Kgalagadi this weekend...will try to get around to it after I get back. Will PM Grant so we can set up on the same parameters...

[Umlilo]

Cameras and lenses is a matter of horses for courses. A useful tip for cropping. Convert image in CS5 or CS4 to a smart object. Do the cropping and flatten image again. You will be suprised in the result comparing to normal cropping. Enjoy the photographing and processing. Gert

[RoyC]

I am certainly no expert but since I bought my D3s I don't use the D7000 at all. I prefer to crop the FX image if necessary rather than switch to the DX body. I have "donated" my D7000 to my son instead.

I don't know if there is a technical explanation or not but for my purposes "it is what it is".

[Green Gorilla]

...will try to get around to it after I get back. Will PM Grant so we can set up on the same parameters...

Will be interested to see what you both come up with. have the 7D. Love it. About to pick up a 1D4, I love it already.

[Grant Atkinson]

Just writing this to let any of the Canon guys know that were following this thread that I have written up the first comparison between the Mk4 cropped and the 7D. The text is on my blog
http://grantatkinsonphotography.blog...non-1dmk4.html
cheers
Grant

[swainsons]

Just writing this to let any of the Canon guys know that were following this thread that I have written up the first comparison between the Mk4 cropped and the 7D. The text is on my blog
http://grantatkinsonphotography.blog...non-1dmk4.html
cheers
Grant

Thanks Grant,

Thats EXACTLY whhat I was after from my initial post. Reality for me anyway is that DX will be good enough (Barring higher ISO) for what I do.

Thanks for your efforts.

NIKON NIKON NIKON, PLEASE PLEASE PLEASE send us a D300s upgrade.

Regards

[walterpike]

To all intents and purposes the D7000 is on a performance level, a D300 upgrade.

[swainsons]

To all intents and purposes the D7000 is on a performance level, a D300 upgrade.

I dunno if I agree with that completely..... If I had a d300s I would certainly NOT upgrade/ downgrade to D7000, as a matter fact I am finding it hard to upgrade my D90 as the specs are just to close, or rather, the cost does not justify the small increment in performance enhancement, hence me rather waiting to see what Nikon is gonna do with the D300s upgrade.

Regards

[floydthebarber71]

Just the thread I was looking for! I've been browsing some FF pics, and at the same effective focal length of my D7000 DX camera, there just seems to be more to see. I don't know if I'm dreaming, but if you compare a DX image shot at 35mm and an FX image at 50mm, I just somehow see a lot more detail in the FX image. I can't get my head around it since you'd expect the DX to be clearer since it has more resolution. It just doesn't look the same?

Morkel's post just showed me that I wasn't dreaming. Ok, so you can't compare a D3s with a D7000. But what about a D700 with a D7000, then?

I know a photographer should just end up using what he has available to him, but in the case of FX vs DX, it really defines lens choices and how you shoot and it's a biggie, imo.

[walterpike]

Zaahir, I own a D90 and a D7000. The D7000 is a different class to it. I would choose a D7000 over a D300s because I think made it made the D300s redundant (in performance terms - not some of the features) it's just a different generation - the D700 is a step up - but obviously it's far behind the D800. My D800 order is already in the queue. Sure that there will be D300 upgrade that will change the hierarchy but at the moment that's how I see it.

[walterpike]

I know a photographer should just end up using what he has available to him, but in the case of FX vs DX, it really defines lens choices and how you shoot and it's a biggie, imo.

Remember that with the Dx you are cropping the Fx image of the same focal length. It's only the field of view that changes.

[swainsons]

Remember that with the Dx you are cropping the Fx image of the same focal length. It's only the field of view that changes.

This is another thing I dont understand. Even on Nikons website http://imaging.nikon.com/lineup/lens...ator/index.htm, it clearly shows how the "view" changes between dx and fx, and clearly dx brings the subject closer....

Or am I just dof???

[cagenuts]

This is another thing I dont understand. Even on Nikons website http://imaging.nikon.com/lineup/lens...ator/index.htm, it clearly shows how the "view" changes between dx and fx, and clearly dx brings the subject closer....

Or am I just dof???

It's the same as if you were to shoot an image in FF frame mode and then crop it later in post processing to the image dimensions of the DX shot. Depth of field DOES change of course.

[Grant Atkinson]

This post is purely to try and provide a different way of looking at things for Swainsons questions about DX/FX
This is an important thread as mentioned by earlier posters, when the sensor characteristics of your choice of dslr have an impact on your lens choice. With lens choice in mind, I have found it easier to stay clear of confusion by not focusing on crop factor, field of view crop, FX, DX etc, and instead I look at how big the individual 'pixel' is on a camera sensor as the first number to give me the information I want. Therefore I think of a D3s as an 8.45micron pixel pitch camera, and the D300s as 5.49 micron pixel pitch, the D7000 as 4.78 micron pixel pitch. The smaller the pixel pitch, the greater the subject size, all other things being equal, I find this the easiest way to quickly figure out which sensor may be better suited to particular circumstances. If you have an FX/full frame camera with pixels of small size (4.88) like the D800, then many of them fit onto that large sensor, which gives you 36mp. If your sensor size is smaller, DX, and you fill it with similarly small pixels (4.78 microns) as in the D7000, then you only get 16mp.
Comparing the quality of image that those pixels produce is a different question.
cheers
Grant