XF-100 - My impressions after a 100 hours with the camera plus some test videos

[Martin Doppelbauer]

I have been using the XF 100 camera since summer. There are a lot of things I liked and some not so great features. If you are interested: I have collected my impressions here: Canon XF 100.
The review has links to a couple of test videos (day shots, night shots and time laps (interval recordings)) plus my preferred custom picture settings.
Hope this helps.

[Andy Wilkinson]

Very interesting reading. Thanks for posting the link.

[Allan Black]

Yep thanks for this review, nice video with the BAYER sign nicely exposed :)

Cheers.

[Robin Davies-Rollinson]

Martin - a very good advert for the camera!
I especially like your Karlsrűhe night shots. How much gain - if any - were you using?

[Steve Maller]

Thanks for taking the time to do this.

I have one comment/observation, apropos your comment "As a consequence there are always memory gaps between adjacent clips and chip cards can never be filled up to their true capacity."

I have heard this, but have not found this to be the case. I've shot several events, and have run my 16GB Sandisk Extreme cards all the way to the end with automatic rollover to the second card, and have never seen any unused space on the cards. They all reach their full capacity. But then again, I usually format the cards before I start recording, so maybe that makes a difference.

[Pavel Sedlak]

Originally Posted by Martin Doppelbauer;1699843...

Contrary to Canon's claims this camera does not come with a ND-filter. ND means 'Neutral Density'. It is an optical element that can be moved into the light path. Most other cameras of a similar price point have at least one such filter (some have two - like my Sony HDR-FX1 - or even three). The XF 100 has none. What Canon calls ND-filter is in reality an electronic attenuator (aka negative gain). As this negative gain does not prevent the sensor from overloading in bright sunlight the XF 100 always needs to close the iris when the sun comes out. A shallow depth of field can only be achieved in moderate to low lighting conditions (or by attaching an external ND filter in front of the lens).

The ND filter isn't a negative gain. It is some control of the chip sensitivity. The only limitation is the lower range of the control against an optical filter (max is 1 / 16 vs 1/64 with the optical ND filter). It really works.
Negative gain (-6dB and -3dB) has no effect on the sensitivity of the chip.

[Mikko Topponen]

Why are people still propagating that "there is no ND filter, only negative gain" when it's wrong. There is an optical ND. It's just crippled the same way they are on consumer cameras (like the HF G10). It goes into place automatically when the lens reaches F4. So it's not manual (hence they call it "electronic") but it is definitely an optical ND. Hence completely REAL. You can even see it move into place if you watch into the lens while it's at F4 and ramping down the exposure.

[Pavel Sedlak]

Changing the optical ND filter can be seen on the record, I know this from my XH-A1. So I think that XF100 has the electronic ND filter (changing is not seen, it is slow and smooth after switching ND filter.). But it works, this is not a negative gain because there is no overexposure when using the ND filter and a lower aperture.

[Pavel Sedlak]

Another inaccuracy is the description of the change shutter speed. You can change the last two shutter speeds without opening the LCD panel (eg the value 1 / 50 and 1 / 100 in the speed mode or the value 1 / 50 and 1 / 25 in slow mode), just push the shutter speed button repeatedly. Opening the LCD panel is only necessary when changing the value of the shutter speed.

[Martin Doppelbauer]

See here for the ND filter: Test Canon XF100 sorted by score with grades, test images and technical data
I'll check this evening if an ND filter is actually visible through the lens.

[Martin Doppelbauer]

Originally Posted by Robin Davies-Rollinson

Martin - a very good advert for the camera!
I especially like your Karlsrűhe night shots. How much gain - if any - were you using?

Gain was on auto and maxed out at 21 dB if I remember correctly. The grain is remarkable low for such a small sensor.
Correction: I just checked the metadata. The gain in the opening shot (train) was fixed to 0 dB. All other shots were made with a fixed 12 dB gain.

[Martin Doppelbauer]

Originally Posted by Steve Maller

Thanks for taking the time to do this.

I have heard this, but have not found this to be the case. I've shot several events, and have run my 16GB Sandisk Extreme cards all the way to the end with automatic rollover to the second card, and have never seen any unused space on the cards. They all reach their full capacity. But then again, I usually format the cards before I start recording, so maybe that makes a difference.

My cards were also initialized in the camera before recording. I had a lengthy mail exchange with Canon's Service about this issue (they even went back to Canon Japan) and have basically quoted their explanation in my text. I even sent one of my cards in and they returned it after a few weeks saying this was normal behavior. However, the issue may have something to do with CBR versus VBR. All the recordings I made were 35 mbps VBR. Did you use 50 mbps CBR ?

[Martin Doppelbauer]

Originally Posted by Pavel Sedlak

Changing the optical ND filter can be seen on the record, I know this from my XH-A1. So I think that XF100 has the electronic ND filter (changing is not seen, it is slow and smooth after switching ND filter.).

That's exactly my point: You see a visible switch in brightness when an optical ND filter is engaged.
BTW, what would be the technical difference between an electronic ND filter and negative gain ? I can't think of anything...

[Martin Doppelbauer]

Originally Posted by Mikko Topponen

You can even see it move into place if you watch into the lens while it's at F4 and ramping down the exposure.

Well, I was starring at the lens today and really couldn't see nothing for sure (even with a magnifying glass). Everything is very tiny. You see some changes while the iris closes down to f4. There may be something just before ND 1/2 is coming up. When ND 1/4 and ND 1/8 are displayed nothing more seems to change. All in all this is much too tiny to determine what's really going on.
After that experiment I was looking into my XM2 and there was a clear difference when I pressed the ND button.
BTW, the XM2 has an optical ND filter that is engaged electrically (in contrast to the Sony HDR-FX1, which has a mechanical knob). Still Canon doesn't call the XM2's optical ND-filter "electronic". But it does so on the XF 100...
Sorry, I am not at all convinced the XM100 has an optical ND-filter but of course I can not prove otherwise, as well.
The fact remains that the ND-filter can not be engaged or disengaged by pressing a button so you can not use it to play with the depth-of-field. I will modify my review accordingly.

[Pavel Sedlak]

Originally Posted by Martin Doppelbauer

That's exactly my point: You see a visible switch in brightness when an optical ND filter is engaged.
BTW, what would be the technical difference between an electronic ND filter and negative gain ? I can't think of anything...

This is very simple (but my english isn't very good .-) ).
The negative gain is an attenuation in the signal processor of the camera, does not affect the overexposure of the chip, it has impact on the amount of the visible noise. You can say that "zero gain" is not really 0dB but +6dB, so -6dB attenuation is in fact a zero amplification (a small amount of the noise). It just depends on the manufacturer how he marks "a zero value" of the gain on the display of the camera.

The electronic ND filter reduce the sensitivity of the chip, for example by reducing the voltage on the chip (of course I do not know the specific method of this regulation), it has a noticeable effect on the overexposure - this effect I can test in easy way. This can also explain why the regulation by the electronic ND filter is lower (max 1/16) than the regulation by the optical filter (max 1/64).

So you can use a negative value of electronic amplification and the ND filter together. I think that the signal amplification is a matter of DSP processor while the ND filter is a matter of voltage regulation of the CMOS chip.