Solved Rendering Resolution

Hi all - I'm new to the forum although I've been a subscriber to Derek for a few years (at least!) My question isn't as much about Movie Studio as much as it is drawing on the experience of members. I hope this was the correct forum to post it in. Also please note that I attempted to search for this answer but couldn't find it. I know the answer's probably on the Internet somewhere and I'm probably simply not able to describe my question succinctly enough.

Ok, so, a friend has asked me to convert a VHS tape to a DVD. I've done this many times (a million or so) successfully but I've always wondered if I was saving the captured video to the right resolution, minimizing any loss as the video is converted from one format to another.

I use a Composite USB converter (one video plug, not three) to first convert the video to a file. The device I use needs to use its own video software to capture and save the video. I'd prefer to use Music Studio, but my device doesn't seem to be compatible with this kind of device, or maybe just this make. Regardless, I then take the file and use Movie Studio to fade, put markers, etc, then export the file again, and create the DVD.

What I'm wondering is...When I initially capture the video, should I save it at a higher resolution? VHS is natively at 640x480 (I think), and when I save the video file at 640x480, it looks exactly the same as when I save it at a higher resolution. But I would expect this! My question isn't about that, but rather when I go to use the file in Movie Studio and subsequently create the DVD, will starting the file from a higher resolution (even though it's only an upgrade from on a fuzzy 640x480) wind up looking better on the DVD than if I initially rendered it at 640x480? My gut tells me that the video will look the same when everything is finished regardless of what resolution I rendered the video at, but I always wanted to confirm that if I start it as a small resolution, that it wouldn't look more blocky on the DVD than if I started it at a larger resolution.

I know the above sounds a little convoluted and I hope I was able to make the question clear. Thanks to anyone who weighs in! - Jeff

Why not do a short test to compare the two different renders and decide for yourself.

Personally I consider the less rescaling the better so I'd stick with 640x480. Upscaling then downscaling will most likely result in image deterioration each time.

Hi Jeff,

I agree with Eric, a short segment test would reveal which was better to your eye and on your DVD viewing equipment. Although up-scaling from Standard Definition and then down scaling it back to Standard Definition (DVD) on it's own most likely will cause more time and headaches than it would probably be worth, there may be some other modifications you may consider worth your time, again to test a short segment.

You might find some relatively inexpensive up-scaling software that may (that 'may' is a bet, and so is 'relatively inexpensive', you have to try) get you to 720p and I think you could render that on BluRay. Many of these software companies provide a free download trial to test out before buying. If BluRay players are available, that might provide a bit of resolution improvement, but a lot of these maybe's are based on the available equipment. For example, I can render to 720p on BluRay and when played back on my Sony big flat screen (it does some magic) the video is difficult to tell that it isn't 1080 FHD.

You then could bring that into Movie Studio (or your original captured VHS if the up-scaling does't work out) and perhaps apply a light sharpening, adjust the white balance, adjust the contrast/brightness, and some color correction and perhaps make a significant improvement. As you make these changes and save your setting off to presets, you can then apply the FX presets to future conversions saving you time, after your initial time investment. I would think it would only take a small amount of each of these and together you may come out with a combination that will then make your conversions pop, which would work with the majority of footage. Footage that is really poor, like to dark, to bland, to fuzzy, etc. may takes some additional work on just those sections.

I hope others have additional information and suggestions to help you improve on your conversion.

Thanks for the replies! Unfortunately, my eyes aren't so great (think coke bottle glasses) and I'm constantly having people tell me details I'm missing. So even though I've done my own tests, as has been suggested, and didn't find much of a difference, I know not to trust my opinion when it comes to visual details.

The rest is very good advice and much appreciated! I was thinking there might be some conventional wisdom out there on this matter that I haven't yet run across that I could draw from when approaching this project. Any other opinions on the subject are welcome!

Well Jeff, I am starting to feel your pain, in the vision department. My eyes just aren't the same any more, as would be expected at my age I suppose. It does present an additional level to your puzzle.The general rule of thumb and from a practical stand point, we cannot make video look better than the original. Knowing that, as I said previously, there are some tricks we may use to somewhat restore old generation film (videos) to look better, but without some very sophisticated and expensive software and equipment, we are pretty much stuck with making it look better by perhaps enriching the colors, a slight amount of sharpening, adjusting the brightness and contrast and maybe setting the white balance. If the original was taken with a camera with a quality lens, and the sensor made a quality recording, even those adjustments may not make a big difference.

Regardless of the techniques you employ, if your eyes are a stumbling block, you most likely are in need of a third party to review your test to help determine what may be better or worse. As producers we may have the knowledge to edit, correct, and render out a video by the book, but ultimately, the viewer decides if we have done a good job, not the film critic. The good part of your conversion is getting a copy off the tape and into digital form before the tape degrades any further, therefore preserving whatever quality is left in the tape, for many years in the future. Good Luck Sir with your venture.

Hi Jeff.
Really interesting question and probably more difficult to answer than you might imagine.
Capturing analog video signals to digital has an underlying level of complexity that can be challenging to simplify – although is really enthralling if you are so inclined.
I saved the link to this old discussion on another forum a good few years ago and revisit it every now and again when I need to refresh my memory on various issues. It was probably easier to sing along with back in the day when analog to digital was the environment we played in on a daily basis than it might be today, but might give a bit of insight into some of the considerations in digitising a VHS analog signal.
After extensive technical discussion forum member Xesdeeni responded to the original and ultimately restated question of “What's the best resolution to capture (VHS to)” with the following advice:
“VHS … has about 240 lines of (horizontal) resolution. Depending on the Extended Kell Factor you want to use, this is equivalent to about 450 horizontal pixels. So 450x480/576 is roughly equivalent (note that for most capture boards, you will want to capture at the maximum resolution and scale down with software for the best quality…). However, … 352x480/576 may be sufficiently close …
S-VHS has about 400 lines of (horizontal) resolution. Using the same Extended Kell Factor (EKF), this is roughly equivalent to 750 horizontal pixels (this is one of the reasons why I tend to use a smaller EKF). So for S-VHS, use 720x480/576 (obviously if your card can only capture 640x480, then you use that; if your card can do 768x576 then use this).”
To summarise the old wisdom:

• There are a LOT of factors that come into play when converting an analog VHS signal to digital pixels that will influence the quality of the capture. This makes it difficult to provide definitive guidance on a specific digitisation process depending on the source material, equipment being used, bandwidth of the analog signal (which can vary between broadcast, VHS and SVHS – mand even between recorders/players) etc. Trialling the alternatives to see what worked best was always the standard recommendation and continues to hold good in the advice from EricLNZ and Eagle Six.
  
• Capture to the highest resolution your capture device is capable of (rationale being that most devices were designed to capture at their maximum resolutions and lower resolutions were downscaled on the fly – better to capture at max res and if required scale down in post processing). Note though that this particular piece of wisdom was born in an era when computer processing power was significantly less than we take for granted today.
  
• Always best to capture to a resolution as close as possible to the intended delivery format – the fewer times you have to rescale the better. If the target is DVD then capture to 720x480/576 if possible. This tends to hold true no matter what era we are operating in.

Coming back to your original question, capturing NTSC to 640x480, you shouldn't be losing any information that would otherwise be available from the source VHS. The question then is whether post processing and resizing to 720x480 introduces any issues or artifacts is what you would need to test.

Cheers, Robbie

Thanks for the responses Robbie and George! A lot of good information, and I think I got the answer I was looking for! Thanks again!