gamma

Exciting things to come at APVideo

October Update with lots of 4K

Evening all! It's been a long summer, made even longer by fantastic work with friends and brilliant clients. My last post 'Filming with the JVC GY-LS300..' has actually been in the works for months, but I didn't see fit to release it without a couple of the accompanying videos. As well as completing productions for Screen Systems, I also worked with NewsShooter.com to produce the coverage and blogs over IBC 2015. It was great to work with Dan, Elliot, Matt and the others from the NewsShooter team, more on IBC in another post.

On returning from IBC, I met up with Dan and we played around with some old 'budget' manual lenses with the LS300 and got some interesting results. Many of the lenses were purchased for £5 or at least under £10, giving it the budget aspect. The LS300 is also somewhat of a budget option for a video camera, but with the eagerly anticipated J-LOG gamma curve firmware update, much more visual quality and dynamic range can be captured. Together, that makes the 'budget lens challenge', in which you purchase a cheap lens, and make a short vid with it on a budget setup!

Can you do the 'Budget Lens Challenge'? Send over your results and #budgetlens on twitter to @plowman91 and @theNewsshooter!

Coming up, I am working on part 3 and 4 of the JVC GY-LS300 camera review which will include using J-LOG; filming and grading with it, as well as including the budget lenses I've acquired as part of the budget lens challenge!

Thanks to Manfrotto and WTS Broadcast for your support.

What is GAMMA? Colour Correction Advice!

When out capturing footage, how many of you use the 'Standard' picture style in your camera? Do you shoot 'Neutral', 'Cinestyle' or ever RAW? It is always interesting to find out, as the workflow and manipulation of the footage is different depending on your input video signal.. Did you burn in your brightness and contrast, or did you give enough dynamic range to push and pull your shadows and highlights when colour correcting and grading in post production? As I capture my footage on a Canon 60D, it records in compressed .MOV format, which is not great due to the compressed signal. However, by making your image 'flatter' or what looks like hazy and grey, you are able to add or remove detail that may have been baked in during acquisition.

A little case study for you, take my footage that I am working on currently. Here is a screenshot of a clip before I took it into Premiere Pro -

post1

I then colour corrected or 'graded' the clip using a couple of the video effects built into Premiere Pro, namely the 'Luma Corrector' and 'Three Way Colour Corrector' to perform the basic exposure and colour balance corrections.

Where using the 'Luma Corrector' has its advantages over using the 'Brightness & Contrast' or 'RGB Curves' effects is that the 'Luma Corrector' allows you to adjust the Gamma level of the image. Gamma being a extra luma curve that is added to the image after the sensor captures the data which allows the image to be constantly correctly exposed when played back on old school CRT displays. Now, these displays are not so common these days, but it is still a standard practice to apply a gamma curve to the processed video signal.

The advantage of increasing or reducing the gamma using the 'Luma Corrector' is that it removes the 'flattened' or neutral look to the image, while still retaining a constant contrast, resulting in a sharp and nicely graded shot. Here is another shot of the Luma Corrector and Three Way Colour Corrector being used on the same clip as above -

post2

I hope this example demonstrates the advantage of capturing your footage a neutral setting to get the most out of your final product!