DxOMark has posted their analysis of the 5D Mark II. If you look at the comparison to the 1Ds Mark III, the 5D2 is nearly identical at ISO 100, with very small numerical advantages in some areas going to the 1Ds3. As the ISO increases, the 5D2 pulls ahead a bit in nearly every test. Go see the results for yourself. Lab testing is only one part of the story when reviewing a camera, but I think these results clearly indicate that the 5D2 can go toe-to-toe with the 1Ds3 in terms of raw image quality…that is, once those pesky black spots go away.

Update: As of the new 1.0.7 firmware, it appears that the problem is fixed.



Recently the web has been buzzing with news of strange artifacts in photos from the new Canon 5D Mark II. In some cases small black dots appear next to bright highlights. Yesterday someone thought they had found a combination of settings that fixed the problem, but it appears that report was incorrect. At first I couldn’t reproduce the problem with my production camera, but unfortunately I’ve now found a real world image that exhibits the problem. I’ve also been able to replicate it under controlled conditions.

In the 100% crop below you can see where I’ve circled black dots that appear next to some of the highlights. This image was shot at ISO 200 and Highlight Tone Priority, High ISO Noise Reduction and Auto Lighting Optimizer were all disabled. This is a RAW image that was processsed with Canon’s Digital Photo Professional software. I can also see the artifacts when I convert the image to DNG and open it in Lightroom 2.1.




Since the dots appear next to small, bright highlights with high contrast edges, I realized that I could reproduce them by poking holes in a piece of black construction paper and taping it in front of a lamp. I made sure there was enough light falling on the paper so that the dots would be visible against the background. Below you can see 100% crops for ISO 100-25600. All images were shot RAW and converted with DPP. For this test Peripheral Illumination Correction, Highlight Tone Priority, High ISO Noise Reduction and Auto Lighting Optimizer were all switched off.

ISO 100	ISO 200	ISO 400
ISO 800	ISO 1600	ISO 3200
ISO 6400	ISO 12800	ISO 25600

So that’s the bad news. It seems likely that this problem is present on all the new 5D Mark II’s. It’s interesting to note that in the vertical images the spots are on the top of the highlight and in the horizontal images they are on the right side. This really means that the dots are always showing up in the same relative position with respect to the sensor. If we’re really lucky, the problem is something that can be fixed in firmware. A hardware problem with the sensor would be seriously bad news for Canon and for all us early adopters. I’m pretty disappointed that Canon screwed this up. While we wait for a fix, I’m hoping that for my nature photography it will be relatively rare that these dots show up. I’ll be keeping an eye out for them and will post more real world examples as they come.



Update: This is interesting…Northlight Images has noticed that one of the still images shot during the making of Reverie exhibits the black dot problem. Look at the last strand of lights on the bridge, towards the right of the image.

After seeing the early samples, everyone’s been really excited about the video quality of the 5D Mark II. But does it really live up to the hype? Certainly it can produce beautiful shallow DOF images, but there are some issues. It appears that the video is susceptible to moiré, leading to false color artifacts in some cases. Jim Jannard posted a test pattern showing this problem on the Red user forums, and this post on Crunchgear provides a possible technical explanation for the source of the problem. It would be one thing if this problem only showed up in the lab, but unfortunately I’m seeing it in some of my real world footage.



I’ve seen it manifest as out of place red and blue pixels in areas of patterned detail, such as in the rough weave of a polo shirt or in fine hair. More interestingly for my subject matter, I’ve also seen it in moving water in some cases. Here are some example frame grabs and corresponding 100% crops. There’s some JPEG artifacts in these web versions, so don’t pay attention to anything except the moiré.

So far I’ve mostly been writing about the 5D Mark II’s video mode. This evening I was able to get out to the coast and make some still images like the one below. I’m pleased to say that the image quality seems to be at least as good as the 1Ds Mark III.

Take a look at this 100% crop. I shot RAW and applied my normal amount of unsharp mask. Tons of detail and the shadows look good too. ISO 100, 1.6 seconds at f/11. A split ND filter was used to balance the sky with the foreground.

In this article I’ll tell you why you might use a variable ND filter for video, what it is, and how to use it to trick the exposure metering of the Canon 5D Mark II’s video mode. Read on to find out more.



This image is a frame capture from a video clip that I shot this morning with the 5D Mark II. The lighting is direct early morning sunlight, just after sunrise, so it was pretty bright. The camera originally wanted to use an aperture of f/11, but I forced it to open up to f/2.8 so that I could get the shallow depth of field you see here. But wait, there’s no manual controls in video mode. So how’d I do that? With a variable neutral density (ND) filter.




So what is a variable ND filter? It’s a screw-on filter that provides adjustable light reduction. It has a rotating front element (like a circular polarizer), which allows you to control the light transmission of the filter. They’re commonly used by landscape photographers to get slower shutter speeds when photographing moving water. The one I have is the Singh-Ray Vari-ND. It provides about 2 to 8 stops of light control depending on the setting.

Okay, so why did I need to use one for video? There’s two reasons. The first one is light control. If I were shooting stills, I could go all the way up to the camera’s maximum shutter speed of 1/8000 second and I’d have no trouble shooting at f/2.8 without filters. But in video mode the shutter speed is limited, possibly as low as 1/125 according to some reports. So the ND filter gives me back some of the light control that I lost.



Here’s the really interesting part. The variable ND filter also gives me the ability to trick the camera’s metering system and regain some semblance of manual control over the video mode. If a scene is too bright, the camera decides to stop down the aperture. By adding the ND filter, you can use it to reduce the light intensity until the camera decides to open the aperture again. However, something weird happens here. The 5D Mark II first pushes up the ISO before opening the aperture, and then the ISO stays quite high with the new aperture. What’s really cool about having a variable ND filter is that you can fix this by backing off on the filter and letting a little more light in again. It seems that the camera gets “stuck” at the new aperture and will reduce the ISO before closing down the aperture again. Then you can lock the exposure with * and you’re good to go.



Here’s an example sequence of meter readings that illustrates my point. Let’s assume that the shutter speed is staying constant throughout the sequence (in reality it may fluctuate some):

If you’re shooting with a zoom lens, you might even be able to combine this with my trick for controlling shutter speed.

I never had any problems with my original 5D, but I’ve heard of the mirror falling out in some cases. Perhaps there was some sort of problem with the attachment mechanism? Well, I’ve noticed that on the new 5D Mark II you can see two metal tabs that appear to be holding the mirror in place. Take a look at the comparison pictures. You can click for larger versions.

Canon 5D	Canon 5D Mark II (tabs are circled)

Maybe this will reassure any original 5D owners who had mirror problems.