Tag Archives: settings

Shooting Snow and other bright scenes.

Well winter is upon us. The north of the UK is seeing some pretty heavy snow fall and it’s due to spread south through the week. I regularly make trips to Norway and Iceland in the winter to shoot the Northern Lights (email me if you want to come) so I am used to shooting in the snow. It can be very difficult. Not only do you have to deal with the cold but also difficult exposure.

First off it’s vital to protect your equipment and investment from the cold weather. A good camera cover is essential, I use Kata covers on my cameras. If you don’t have a proper cover at the very least use a bin liner or other bag to wrap up your camera. If you have a sewing machine you could always use some fleece or waterproof material to make your own cover. If snow is actually falling, it will end up on your lens and probably melt. Most regular lens cloths just smear any water around the lens, leaving you with a blurred image. I find that the best cloth to use in wet conditions is a chamois (shammy) leather. Normally available in car accessory shops these are soft, absorbent leather cloths. Buy a large one, cut it into a couple of smaller pieces, then give it a good wash and you have a couple of excellent lens cloths that will work when wet and won’t damage your lens.

Exposing for snow is tricky. You want it to look bright, but you don’t want to overexpose. If your camera has zebras set them to 95 to 100%. This way you will get a zebra pattern on the snow as it starts to over expose. You also want your snow to look white, so do a manual white balance using clean snow as your white. Don’t however do this at dawn or near sunset as this will remove the orange light normally found at the ends of the day. In these cases it is best to use preset white set to around 5,600k. Don’t use cinegammas or hypergammas with bright snow scenes. They are OK for dull or overcast days, provided you do some grading in post, but on bright days because large areas of your snow scene will be up over 70 to 80% exposure you will end up with a very flat looking image as your snow will be in the compressed part of the exposure curve. You may want to consider using a little bit of negative black gamma to put a bit more contrast into the image.

If the sun is shining, yes I know this may not happen often in the UK, but if it is then the overall brightness of your scene may be very high. Remember to try to avoid stopping down your lens with the iris too far. With 1/3? sensor cameras you should aim to stay more open than f5.6, with 1/2? more than f8 and 2/3? more than f11. You may need to use the cameras built in ND filters or external ND filters to achieve this. Perhaps even a variable ND like the Genus ND Fader. You need to do this to avoid diffraction limiting, which softens the image if the iris is stopped down too much and is particulary noticeable with HD camcorders.

Finally at the end of your day of shooting remember that your camera will be cold. If you take it in to a warm environment (car, house, office) condensation will form both on the outside and on the inside. This moisture can damage the delicate electronics in a camcorder so leave the camera turned off until it has warmed up and ensure it is completely dry before packing it away. This is particularly important if you store your camera in any kind of waterproof case as moisture may remain trapped inside the case leading to long term damage. It is a good idea to keep sachets of silica gel in your camera case to absorb any such moisture. In the arctic and very cold environments the condensation may freeze covering the camera in ice and making it un-useable. In these extreme situations sometimes it is better to leave the camera in the cold rather than repeatedly warming it up and cooling it down.

Have fun, don’t get too cold, oh…  and keep some chemical hand warmers handy to help stop the lens fogging and to keep your fingers from freezing.

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PMW-350 Scene Files for Download

PMW-350 Scene Files for Download

Alister-350-Scene-flies1

Click on the link above to download a set of my latest scene files. Un-zip and copy to the root of an SxS card, the in the file menu load the files.

These are mainly matrix tweeks. neut2 is one I like that gives rich primary colours while still reasonably true to life. Cine1 is a sudo filmic look Film1 is meant to emulate well saturated film stock DSC-1 is based on Chroma-Du-Monde chart for accurate daylight color Neut is my first matrix tweak for a less green look and warmer skin tones.

Brewing up a Scene File for the PMW-350 (and other cameras)

I decided to write a more detailed post to continue the discussions on scene file settings for the PMW-350. This is a work in progress. Some of this may also be of interest to other camera users as I hope to give a basic description of what all the various settings do.

First off let me say that there is no “right way” or “wrong way” to set up a scene file. What works for one person may not be to anothers taste, or suit different applications. For me, my requirements are a neutral look, not over corrected or too vivid, but retaining a pleasing contrast range. I hope, as this thread develops to explain a little bit about each of the settings and what they actually do in the hope that it will make it easy for you to adjust the scene files to suit your own needs. I hope others will jump in with their suggestions too!

So first of all I have been looking at the sharpness of the image. The principle settings that affect this are the Detail and Aperture settings.

Detail enhances rapid transitions from light to dark within the pictures by exaggerating the transition with the addition of a black or white edge. So it only really works on object outlines and larger details (low frequency). The circuitry that determines where these edges are uses an electronic delay to compare adjacent pixels to see whether they are brighter or darker compared to each other. Because of this any rapid movement within the frame stops the circuitry from working. If you have picture with a lot of detail correction and you do a pan for example the image will appear to go soft as soon as the camera moves as the detail circuitry can no longer determine where the edges within the image are and thus applies less detail correction. A good way to visually gauge how much detail a camera is applying to a clip is to look for this. With a good high resolution camera, set up well, it should not be all that obvious, but a low resolution camera that uses lots of detail correction to compensate will exhibit lots of softening on pans.

As well as adjusting the amount of detail correction (Detail Level), you can also adjust the ratio of horizontal and vertical correction, the maximum brightness or darkness of the applied edges (white and black limit). The thickness of the edges (frequency), the minimum contrast change that the correction will be applied to (crispening) and you can tell the camera not to apply detail correction to dark areas (level depend).

The other setting that effects picture sharpness is Aperture. Aperture correction is a high frequency boost circuit, it simply, in effect, enhances transitions from dark to light or light to dark in fine detail and textures such as fabrics, skin, hair, grass etc. It’s operation is not as obvious as “Detail” correction, but if overdone it can make textures sparkle with flashes of white or black, all very un-natural.

An important note about image detail is that if you have too much of it for the given image resolution then you get problems such as aliasing and moire which manifest themselves as rainbows of colour or buzzing, jittering areas in the picture. If you want to know more about this look up Nyquist theory. This is one of the reasons why downconverting HD to SD and getting a good picture can be harder than you might think as you are often starting out with too much detail (but that’s another topic on it’s own).

So… on to the PMW-350. Out of the box it’s really sharp. The camera has full 1920×1080 sensors, so even with all detail correction turned off the image is still pretty sharp. However most viewers are used to seeing picture with some detail correction, so if you turn it all off, to many it looks soft. If you were going for a really filmic look, detail off and aperture off would have to be a serious option. For my customers though a little bit of subtle “zing” seems to be what they like.

I found that these settings worked well for general all-round use.

Detail Level -14?H/V Ratio +20 (helps balance horizontal and vertical resolution)?Frequency +35 (makes the edges thinner, if your doing a lot of SD you may want to go the other way to -50 so that the edges can still be seen in SD)?White Limit +35 (limits brightness of white edges)?Black Limit +30 (limits darkness of black edges)

Aperture -20

If you are doing a lot of grading and work with low key scenes (large dark areas) you can use the level depend and crispening settings to help prevent “detail” being added to any picture noise. This makes any noise less apparent.

A starting point for this would be:

Crispening +35?Level depend +20

For normal light levels these are not needed with the 350 IMHO. If you are shooting with more than +6db gain then raising the level depend to +60 will help with noise.

PMW-350 Detail Settings


I have finally managed to get my hands on a production PMW-350. I am going to start dialing it in. The first thing to address for me is the over sharpened pictures, so I have been playing with the Paint settings aiming towards a natural, yet sharp look. I have come up with these detail setings. Everything is default except:

Detail Level -16?H/V Ratio +20?Detail Frequency +35?White limit +39?Black Limit +20?Aperture -30

This is still a work in progress.

Next I’m going to start looking at the Gamma curves and Knee. I have a nice Hamlet MicroFlex scope to help with this. Previously I have had to rely on my eye and then check the footage against the scopes in the edit suite, now I can see the waveforms on location. I’ll be writting up both the gamma settings and a microflex review in due course.