Wednesday, September 24, 2014

Fuji S1 – Review Part 26 – Firmware Bug for Raw Images Shot with Shutter Speed Greater Than 10 Seconds – **** UPDATED!

User SnowPlow on the DPReview Fuji Talk Forum has found a firmware bug, and has isolated it to 10 seconds of shutter speed. This destroys a raw image, spiking the blue channel something wicked.

*** UPDATE: I was confused by the thread Snowplow created in which I thought a user posted that he sent his in and the firmware update they applied did not work. So I proceeded with the test and article below. He just posted that the firmware fix was never implied, so he did it and it did in fact work. So I am charging the battery overnight (always apply firmware with a full battery!!!) and will update the article with the confirmation that the fix works tomorrow.

And it worked!

Test with Firmware 1.01

Updating the firmware to 1.01 is trivial:

  • Download the new firmware
  • Format an SD card in the camera
  • Put the SD card in your card reader and copy the new firmware to the top level (I.e. just drag it onto the drive letter in explorer)
  • Put the card back into the camera
  • Make certain that the camera has a full battery, or is on AC power
  • Turn camera on while hold the disp/back button down
  • Follow the menus
  • Turn off the camera and turn it on normally

After that, 10s exposures work perfectly. As in:

Original Test with Firmware 1.00

I decided to put this in a permanent record in my tests, and to isolated the shutter speeds from 6.5s to 10s to see if there is any hint below 10s. There is not. And what one notices is that the dark frame subtraction appears to start at 10s, which is indicated by the image not coming up immediately, but rather showing a “processing: screen for about the same time as the shutter speed and then showing the image.

So it is clearly a bug. (At the time I wrote this, I was unaware that it was already fixed.)

I also isolated it to the raw in a jpeg + raw pair. The jpegs are fine. Go figure. This means that the Fuji is perfectly capable of rendering the jpeg from the raw, and then it destroys the raw. Love that firmware team :-)

The histograms for the jpeg and raw are:

image   image

Hmmm … I think that is clearly a screw up. But do note that the spike is also there in the jpeg. This comes from the presence of candles in the image. They throw heat, and Fuji sensors react by turning images magenta / purple. I proved that video is less sensitive in the S1 than in the HS50EXR, but it is not insensitive.

And it gets worse. If you look at the jpeg, you will not only see the rampant heat signature all over the candles, you will see also several flares in the image in that color. These might be lens flares or they might be hot spots on the sensor, but either way I am not that thrilled to see them. Remember that I shot the Centennial Flame and saw little of this behavior there. Perhaps the sensor was warmed up by the video test I ran just before shooting these. Who can say …

Note that this image was shot at 100 ISO and 10s shutter. It is a perfect exposure, showing 0ev on the meter in manual mode.

And the raw of course is utterly trashed.

Note that I coined the term sledge hammer noise reduction to describe the noise reduction we see in earlier F series EXR models. These cameras really smeared details, even at low ISO. And especially in HR mode. Things got better with the newer cameras, but then this appears in the noise reduction for long exposures. I think we need something bigger than a sledge hammer for this … perhaps wrecking ball.

Here is a matrix of a series of perfect exposures at 100 ISO and over exposures at 1600 ISO. The 10s issue appears in both. The shutter speeds are 6.5s, 8s and 10s. The issue definitely starts at 10s, when the wrecking ball hits.

Note also the stripe of devastation along the top in both 10s exposures in the raw image. What’s up with that?