Infrared Video in Daylight using Sony Night Shot

Sony’s infrared NIGHT SHOT setting on their camcorders is useful for nocturnal wildlife forays, both for the wildlife itself when a visible light source cannot be used and for videoing cutaways of the watchers and drivers in the pitch dark. It is said to operate by moving the filter from the sensor thereby allowing near infrared and infrared wavelengths to be recorded. I wondered if it would be possible to use Night Shot in daylight to turn the camcorder (AX33) into an infrared camera by putting suitable cutoff filters over the lens.

Unfortunately, life is not that simple. Even with an 850 nm IR filter, there was massive overexposure on the Auto setting—the only setting permitted since in Night Shot mode manual exposure adjustment is blocked. So I started stacking neutral density filters over the 850 filter. Eventually with an ND8 plus ND4 (i.e. 5 stops) I could get a reasonably exposed image even in bright sunlight. I return to this set up below.

I also tried a 720 nm filter to see if I could generate faux colour infrared footage. Using the technique in Final Cut Pro X I have used with my 720 nm infrared-modified Nikon D7100, I could get a weak blue in the sky but nothing really worthwhile.

In trying to find out whether or not anybody had attempted to use Night Shot by day I came across a small Flickr group. Members of that have used a 2003 model Sony still camera (DSC-V1) which has Night Shot. Again an IR filter plus ND filters were the answer.

The original footage has the usual weak green hue. I did a simple black-and-white conversion. Noise, always a problem with infrared photography using cameras with small sensors, was evident. Therefore, I used Neat Video for noise reduction but there is a downside in that rendering times are increased markedly—very markedly.

To try the set-up out I tried a few hand-held shots in the village. You will see from the footage that at the shorter focal lengths there was peripheral unsharpness. I do not know the cause. At longer focal lengths, however, that fuzziness disappeared.

While not as convenient or versatile as a modern infrared-converted DSLR, the use of Night Shot does provide owners of Sony camcorders with the capability of taking infrared footage with the simple addition of cheap filters. 

Infrared 'faux colour' video from an IR-converted (590 nm) DSLR and Final Cut Pro X

I do not have a video camera that has been converted for infrared with a 590 nm ('goldie') filter. I do though have a Nikon D80 so converted and could investigate the effect of channel swapping in Final Cut Pro X and the plugins described in my previous post using still photographs on the video timeline.

As you can see, as with my 720 nm-converted Nikon D7100, the process works very well, again proving just as easy, if not easier, than using the various methods available for still images only.

The Nikon D80 produces a noiser image than the D7100, so I also used the Neat Video noise reduction plugin for FCP X. The latter is excellent although rendering is very slow indeed.

Still image from 590 nm-infrared converted Nikon D80 processed in Final Cut Pro X as described in previous post. No noise reduction applied

As above with noise reduction (Neat Video) applied

I am not just planning to use the Nikon D80 with the 590 nm filter conversion for still photographs dropped into a video. Being able to produce the 'faux' colour effects in Final Cut Pro X means that I can take time lapse sequences and after making simple corrections, like dealing with dust spots, on all the images in Lightroom, and compiling the sequence into a video, I can do all colour channel swapping and colour grading in FCP X.

Infrared 'faux colour' video from an IR-converted (720 nm) DSLR and Final Cut Pro X

Shortly after my new-to-me infrared-converted (720 nm filter) Nikon D7100 arrived the week before last, I realised that I could try to make 'faux colour' infrared full hd videos. However, I had no idea whether with the software available I could process the footage. A day or two later a spell of wall to wall sunshine arrived and so I wandered down to the Auld Brig o'Doon and stuck my camera over the wall just to get some footage to import in Final Cut Pro X. In the interests of health and safety I did stand well away from the carriageway just in case a drunk came by on a horse pursued by witches who gather at intervals at Alloway's Auld Kirk.

Safely back home, I imported the footage into FCPX and found that converting the footage was actually easier than doing the same job with still photographs using the widely-known techniques and which I have written about at length in previous posts.

I have had installed for some time the excellent and free colour effects plugins produced by Alex Gollner (Alex4d). Included in that bundle is Channel Mixer a4d and with that plugin the red and blue channels can be reversed to produce the blue sky effect. Very soon I had worked out a protocol that worked best for me, with the proviso, of course, that other settings and effects could be applied to produced a whole range of 'looks' in the final output.

To explain what I have been up to I have made a short video which explains the steps in Final Cut Pro X:

I shall not repeat the procedure here but there are a couple of things to point out. Whoever converted the camera for the previous owner managed to set a custom white balance. The raw footage has that white balance applied. Others have found it extremely difficult to set a custom white balance in an infrared-converted D7100, and I have not yet found a way. The 'Balance Colour' first step of the conversion process is, therefore, on footage being taken with the custom white balance. Without a custom white balance, (i.e. white balance on 'auto' on the camera) I cannot get reasonable colour using the Channel Mixer; in these circumastances 'Balance Colour' does a reasonable job to bring the white balance back in line but not quite a good enough one. Therefore, a custom white balance set as advised for the particular IR filter on the sensor would appear to be essential.

I should also point out that my experience is confined to infrared-converted cameras, and does not extend to those uncoverted cameras with an infrared filter attached to the lens.