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Studio comparison A900, 5DMkII, D3X

This set of full size shots was taken with the still life left set up, because the Nikon and Canon cameras were not here at the same time. It compares the A900, 5DMkII and D3X using the converters supplied by the makers – Image Data Converter SR2, Digital Photo Professional, and Capture NX2. Each small image in the article can be clicked to open a Level 10 quality full size JPEG – beware, the largest is over 13MB of data.

All images are from uncompressed raw files at the maximum bit depth selectable (if a choice exists), at ISO 100, using ‘Standard’ picture look default as defined by each maker. NR and all other similar controls are turned off, and sharpening is set to the minimum or disabled in every case.

Alpha 900 with 100mm Minolta macro (click image for full size file). Minus -0.35 stops exposure correction needed in IDC2 raw conversion to fairly match the exposure set using the Canon, below.

Canon EOS 5D MkII with 100mm Canon EF macro (click image for full size). Uncorrected raw exposure in raw conversion via DPP.

This image has been added on December 16th, it was taken a week after the others; the lighting and position have been replicated (the lights were left undisturbed but the viola was played, so had to be positioned by matching a print from the Canon. The Nikon DX3 was fitted with a 105mm f/2.8 Nikon AF-S VR Macro lens, at f/11; the ISO 80 (Lo-0.3) setting was used with Capture NX2 shadow and highlight adjustments for a fair match to the in-camera JPEG and the other results. Click image for full size.

The point of focus, using the centre focus sensor for each camera, was the end of the fingerboard. Actual focus showed variations between repeated shots with all three cameras, tripod-mounted and working with two Elinchrom BXRi 500 flash heads. The exposure was set for the Canon and adjusted to be perfect at f/11. However, the Sony JPEGs indicated slight overexposure and the Nikon ones even more; -0.35 exposure compensation was used when processing the Sony files, and -0.65 for the Nikon. For comparison, a Nikon shot taken at the ISO 50 setting, with no exposure adjustment, is included.

Alpha 900 with 28-105mm RS Minolta lens at 105mm (identical tripod position). Throughout this test, I noticed that the Sony could almost have been used with a polarizer, relative to the Canon. For some reason, the Sony suppresses specular reflections and reveals more colour in the wood and fabric. It is not just an exposure and contrast difference (and of course, it was not used with a pol). All cameras were set to Daylight WB, but their definitions of this differ. The Sony and Nikon both have a relatively warm colour, the Canon is very neutral.

Canon EOS 5D MkII with 24-105mm IS L lens at 105mm. Again, not as tight as a true 100mm macro – and both the macros do use internal focusing, so it’s not a matter of real lens extension versus internal focus fakery. Or not entirely to do with that!

Nikon D3X with 24-120mm VR Nikkor at 102mm (composed by eye, tripod moved to allow for thickness of camera grip-base design). Uncorrected conversion (required around -0.65EV to match the Canon brightness) in Capture NX2. See ISO 50 version which follows.

Nikon DX3 uncorrected ISO 50 exposure (a little darker than the Canon ‘correct’ original setup). Nikon does not claim an exact EI 50 for this setting, it is just marked as -1 on the ISO range. The flash is repeatable to 1/10th stop, and with experience of using other lenses on the cameras, the general confirmation would be that the Canon is around 1/3rd stop ‘denser’ in typical raw and JPEG results than the Sony, and the Nikon about 1/3rd stop ‘brighter’. Since the Sony has a very much flatter tonal curve rolling off the highlights (preserving highlight detail) this can not be converted to ‘ISO ratings’, but has practical implications, and each camera should be tested for calibration with a studio flashmeter for use in this environment.

The lens choices

The Sony used a Minolta 100mm f2.8 AF (1986) and a 28-105mm RS f/3.5-4.5 (1993). At 105mm, this lens still did not crop as tight as the macro at 100mm. The Canon used a Canon 100mm f2.8 EF macro and a 24-105mm f/4 IS L. Again, even at 105mm, this lens was not matched at all to the 100mm view. The Nikon, with no macro available, was tested using just the 24-120mm VR f/3.5-5.6. This was matched visually to the 100mm crop, and the focal length reported was 102mm. My lens choices were dictated partly by what was available for loan review from Canon and Nikon, and what lenses I have decided to keep for my Alpha 900. The 28-105mm RS Minolta lens may come as a surprise, but has replaced the 24-105mm D Minolta in my 900 outfit; it’s just a much better lens all round desite being about a decade older.

Focus and depth

f/11 is inadequate, with files of this size, to secure enough depth of field for 100 per cent viewing. But f/16 and f/22 (etc) reduced sharpness greatly by diffraction, and some tests at f/8 gave much better sharpness – with so little depth of field they would be unacceptable. So f/11 was selected as the best compromise, showing d-o-f, bokeh, minor focus errors, and being an aperture at which all the lenses used should be up to the demands of the sensors. All three cameras offer lens specific focus adjustment; it did not prove possible to improve consistency on this subject by using the micro adjustments. The A900 was consistently the most accurate in focusing as targeted. All three cameras had the centre AF sensor only active, in single shot mode.

This test shot highlights the need for tilt lenses (or tilt-shift) in the studio with high pixel count full frame DSLRs. Ideally, the shot would be taken at f/5.6 or f/8 with a high quality 90mm Tilt-Shift tilted to align the plane of focus perfectly so every part of the viola from tailpiece to headstock was sharp. Nikon and Canon both offer exactly such a lens; Sony does not. I have a tilt adaptor (ARAX, from Kiev) and two lenses – 50mm Pentacon and 80mm ARSAT – to fit this. These are no substitute for a good range of Zeiss 24mm, 45mm and 90mm TS lenses to fit Sony Alpha!

In practice, you can stop down to f/22 if you want. Though diffraction effects reduce sharpness, it can be restored by careful use of raw conversion capture-stage sharpening to a level which betters any scan from rollfilm. Diffraction sharpness loss is not the death of a decent digital image, it is just another factor like differential focus blur; you can trade it off against depth of field. Do not limit your technique armoury by refusing to use apertures smaller than the supposed diffraction limit!

The image above is one of my first shots taken with the Alpha 900 – at f/22 on the 17-35mm Minolta D lens. Some strong detail recovery sharpening has been used in ACR when processing the raw file. It’s not perfect but proved to me I could rely on my existing 17-35mm and use the same gamut of depth of field techniques I once used on film.

The software

On an iMac 24″ 2.16GHz running OSX 10.5.5, the Sony IDC2 software was fastest for viewing and most stable (used in conjunction with its companion lightbox app). I had not rated it highly beforehand, and was surprised by the improvement over older versions. Nikon was stable and very fast to save files, but slow to view and to build 100% views for checking focus. Canon’s DPP proved unstable, exit-crashing when asked to handle more than 1000 previews (517 files, raw+JPEG) but OK when prefs were changed to show raws only.

All three programs were relatively tedious and slow in use compared to Lightroom or ACR. Canon appeared to apply a more subtle sharpening and a very steep midtone curve. Sony’s sharpening was coarse and when set to its minimum (not zero) did not seem to aid fine detail recovery (checking these files in ACR revealed better detail, but the Canon files were also improved by ACR). Nikon’s files could not be checked yet using ACR, not supported at the time of this test.

Despite the speed of IDC2, I felt it did the images no favours. Minus 100 sharpening does not prevent fairly ugly coarse sharpening appearing in the shot, and I am told that IDC2 recognises whatever in-camera sharpness was set, and uses this as the very minimum. Since part of this test involved using the defaults of the cameras (Standard picture setting, and no adjustments to contrast, saturation, sharpness etc) plus zero optional processing (NR, DRO, D-Lighting, Lens Shading compensation etc) IDC2 has slightly skewed the view of the raw files.

Why this test?

I had been using the Canon 5D MkII for magazine reviews for two weeks, and the Nikon D3X arrived on the day the 5D departed (again, for a magazine test report). It was necessary to set up something for a planned article comparing the three cameras. Like most of my tests, it is practically based, not a test-chart exercise. I set up and light a subject as if I was taking it for real, and use the camera as I would expect to. I then see what I get.

Update Dec 16: Nikon is sending me a 105mm VR Macro Nikkor, and I will update the shot (need to set it up again as close to this as possible). While I am not happy with the overall performance of the 24-120mm VR on the D3X, I am satisfied that at f/11 in this studio conditions it is not degrading the D3X result, relative to the zoom lenses tested on the other two cameras, but a Nikon macro lens shot is missing and this will be addressed.

All I can tell you for sure is that any one of these cameras will do this job perfectly and the differences you see are insignificant in an A2 reproduction, whether from my Epson 3800 (seen) or in litho print (unlikely to happen!).

– David Kilpatrick

10 comments to Studio comparison A900, 5DMkII, D3X

  • elthamnorth

    Excellent reoort! I shoot a d200 with the 17-55mm f2.8, and I have done some tests comparing the d700 and a900. I have also looked at the various 5dmkii testes including yours..

    Your comment about the a900 and reflections.. I noticed this too. Some lenses seem to cut through reflections to allow light behing to come through. I found this with my Contax G1 and its Zeiss lenses, and the a900 and the 24-70mm Zeiss.

    I think its very hard to decide what to do in terms of an upgrade. I did not find the new Nikon N 24-70mm f2.8 to have lower distortion than the 17-55 f2.8. But the Nikon 24-70mm f2.8 L seems to have less barrel distortion than its Nikon comptetitor.

    My major concern is the 5D MKii’s AF performance. Does anyone have some objective comments?

    Karl

  • Mal65

    Nice article but not as solid as the prior article with the jelly beans. I absolutely loved that one – there are no weak points there at all.

    In this article the viola was moved, the cameras were not all there at the same time and most important there were focus differences as you mentioned. Still you did a great job.

    I have long been fighting with front and back focus issues – even back to my SRT 102. I had issues with my a700 and sent it back and it is now prefect. I love shooting at F1.4 or 2.0 and never realized how amazingly sharp the 50m F1.4 is until I got this camera back from Sony. But with the machinations of going thru all that, I came to realize that the indicated spot central realestate as inscribed on the finder does not match the actual area in which it works. The actual area is wider. Secondly and more important is that whatever size of the focus sensor – if there are solid objects in front of the desired object the focus mechanism will choose the closest item. The sensors focus mechanism views a solid plane in space which is parallel to the camera. In this case the strings are in front of the end of the fingerboard. And since the strings are not in the plane of the focus area, the closer end of the string would be chosen. The manufacturers program the sensor to set focus to the closest item when there are multiple items in the sensors view.

    Canon claims its spot meter is 3.5% of the frame. If you do the mathematics a 3.5% area in the center of a rectancle takes up almost 20% of its horizontal length and height (.2 x .2 = .04 or 4% of the surface area). That is way too large to be a spot meter and a serious defect in the Canon. I suppose they do that so that the mechanism can work to a lower light level. I believe the spot focus area in the Sony is the smallestof the three and that is why it focuses more accurately and consistently than the other cameras. However, I cannot find any claim for the area from either Nikon or Sony.
    Please check my response to your “Sony Alpha 900 and Nikon D3X raw file Noise comparison” on this site.

  • FramerDave

    It is nice to see comparison with a level playing field but I would only go as far as providing the exact test conditions. As to the cameras and lenses being used I believe in the “putting your best foot forward” approach. What does fairness got to do with able to achieve better and higher if it is available to you? Why can’t each company “stack the cards” so to speak by bringing out its top gun? Granted the 100mm macro might be the sharpest lense for this situation but this is not a golf game with handicap. I am all for “let’s see what these babies can do.” Trying to be fair would only incise fans of each club. If you have send your best athlete to the olympic you can no longer cry foul.
    If at all, this test is in favor of the Nikon because nobody takes the cost into serious consideration. With that tone, aren’t we already saying we are really only interested in the results? Why stop there?

  • bakubo

    I wonder, does the DNG converter work with D3x files yet? If it does then you could, for now, use that so that you could work with ACR 5.2.

  • admin

    Thingomy – you don’t work with studio flash, apparently? ISO 100 is essential for studio flash work, and ISO 50 (in the extended range of the Nikon) even more so. Bear in mind that these are fairly small 500Ws semi-pro flash units with relatively inefficient 60cm softboxes, and need to be at MINIMUM power to even allow f/11 as a working aperture at ISO 100. After using the A900 since its launch, I am increasingly using ISO 100 because of improvements in red channel noise meaning sky tones are less noisy; initially I stuck to ISO 200 for the reasons you consider desirable.

    The alternative solution would be to have shot using the flash power to bracket the exposure, it can be incremented in 1/10th stop steps globally from the Skyport controller, but in this case only increased not decreased. I did make tests at other apertures between f22 and f8 and determined that f11 gave the best balance between sharpness, depth of field, and diffraction losses.

    The only negative bias against the Sony present in this test is the use of IDC2 to convert a raw file which had 0 sharpness set in-camera. IDC2 translated this as ‘normal’ sharpneing and applies a fairly coarse USM-type sharpening, which shows in the lines down the instrument strings and the black haloes round the grains of rosin. Out of choice I would have used ACR 5.2 to convert the Sony file, because the result is far more detailed at pixel level, but this would be unfair to the Nikon as ACR 5.2 doesn’t handle DX3 files yet.

    Everything is a compromise when absolutely identical software and optics can not be obtained.

    The Canon test can not be repeated because the Canon has gone back home. However, Nikon is shipping me a 105mm VR Nikkor macro today, and it should be easy enough to set up the viola again and replicate the flash powers (2.3 backlight, 4.7 sidelight) and camera position. Sigma is sending me two 28-70mm f2.8 lenses to compare the A900 and D3X with supposedly identical glass.

    What’s interesting about reactions to this test elsewhere is that each brand’s users consider it unfair to their own brand – which says more about brand loyalty than about the results!

    David

  • Thingomy

    ISO 100 is in the extended range of the A900, right? It’s native ISO is 200, if it’s anything like the A700, the DR will be about 2/3 of a stop below what it should be, among other quality issues caused by this.

    You are using old film optimised lenses on the Alpha (for understood reasons of practicality).

    Exposure was calibrated off the Canon, over exposure in the case of both the other 2 put them at a significant disadvantage.

    As a result of the above, this test extremely biased against the A900 (and to some extent the Nikon); I would like to say that I’m surprised to find 3 such errors in an article this short, but I’m not. It’s widely known that there is a great deal of prejudice in the media against Sony in the DSLR field (often due to brand loyalty/bigotry and/or volatile advertising revenue streams from the big 2: in the broadest sense corruption). I would have thought that a site named PhotoclubAlpha would be above this and would be fair, I can only assume/hope in this case it’s because of sloppy reporting.

  • alphaomega

    Another exellent article with real life comparisons. Interesting the conclusion is that all three will do the job to A2 printing. I am not really surprised at that considering Sony has fabricated the D3X sensor and all three companies are very capable camera developers.
    So the scene is set for a real battle between the three DSLR giants.
    As a personal view I can imagine that all Canon glass owners will go for the 5DII, whereas all Sony owners of Sony/Minolta glass will happily embrace the A900. DK has just pointed out that so much of the old Minolta glass will do fine on the A900.
    The interesting part will be Nikon glass owners needing or wanting 24 Mp FF. Some have Canon glass already. It is interesting to note on the Nikon D3/D700 DPR forum quite a few 1D users have switched to D3/D700 but kept their Canon lenses. They may go back to Canon and purchase 5DII if they need 21 Mp and has in the past considered the 1DsIII too expensive and spec’ed beyond their requirements. Other Nikon users needing 24 Mp FF have purchased the A900 and Zeiss glass already. So the remaining Nikon owners not needing D3X prof. spec. but wanting 24 Mp have a choice. Buy the D3X and fork out big money, go to Canon or buy the A900 and Zeiss/G glass for the same money as a D3X body only. Then there is the residue without a current investment in suitable glass. The majority will probably go for the Canon 5DII as the price difference compared with A900 is not too large. Interesting times ahead.

  • Dr.Harout

    Nice article.

  • alexramos

    Hi Dave…

    Will you show us some examples to high ISO??

    Good review…

  • planetMitch

    Excellent report David! Wanted to let you know that we’ve added it to the 5d wiki at //planet5d.com.