Zen Tip #3: Why Is The Preview Window Lagging So Much in Sony Vegas?

: By: Derek Moran; In: VEGAS Pro; Published: 10 March 2016; Last Updated: 02 September 2022

This is Sony Vegas Zen Tips #3 and today I am explaining why the Preview Window lags so much and how to fix it using many different techniques.

So why is my Preview Window lagging so much, when I’m trying to edit my project? Well before I answer this, everyone needs to realize that all Video Editing programs suffer from some degree of lag or dropped frames – this is normal.

When a video is playing back in the Preview Window, it isn’t simply playing back like a video does on your computer or TV. It is actually being de-compressed in real time, with millions of computations occurring in your CPU and Graphics Card every second.

The more a video has been compressed, the harder it will be to de-compress it in real time. That’s why video from a GoPro camera can be lagging like crazy, because it is super compressed. Whereas on the other hand, you may have a super large un-compressed AVI video playing, that plays back buttery smooth in the Preview Window.

When you are playing back video in the Preview Window, often you have many different video tracks all playing at once and some of those tracks also have VIDEO FX applied. That is lot of different information that needs to be computed into 25 or up to 60 frames per second! There is a really easy way to understand all this. How long does your computer normally take to render a 5 minute video? Let’s say it takes 10 or 15 minutes.

When your Preview Window starts to lag, it is because you are expecting your computer to magically do in real time, what actually takes at least two to three times that amount of time to do!!

So what are the solutions to making video less laggy in the Preview Window?

What can you do to at least take the load off a little and get the Preview Playback to be more smooth.

Solution #1: Adjust the Preview Window quality settings

Don’t set to Best & Full – that’s asking the impossible for most computers. PREVIEW OR GOOD are better options and if you also set to Automatic, Sony Vegas will choose what works best.
And remember, you don’t have to freak out. The Preview Window does not affect your final rendered video. It is just a temporary setting for while you edit.

Solution #2: Use the inbuilt Proxy Video Creation Tool

Inside Vegas Pro 13 and Movie Studio Platinum 13, you can create Video Proxies in the Project Media tab. This feature renders out easier to play video versions of all your video clips, which will make them much, much easier to edit with.

Right-click a video in the Project Media tab and select Create Video Proxy.

For the easier to play proxy versions to work, it is important to set the Preview Window to Draft or Preview - this will tell Vegas/Movie Studio to play only the proxies versions.

Set the Preview Window back to Good or Best and then the original HD versions of your videos will play instead.

Solution #3: Create your own Video Proxies outside of Vegas

If you are using an older version of the Vegas or Movie Studio, which don’t have the in-built proxy tool, you can create your own Video Proxies before you begin editing. I actually have an older tutorial that explains how to do this here:

How to do Proxy Video Editing using Sony Vegas and Movie Studio - Zen Method

Solution #4: Use GoPro Studio to create Cineform.avi Videos

If you install an old version of GoPro Studio, it will allow Vegas to render videos using Cineform codec. Cineform codec is one of the best formats to edit video with, because it is a relatively uncompressed format. Read this tutorial here.

Solution #5: Selectively Pre-Render Video

You can selectively pre-render parts of your timeline into small video chunks. This makes it much easier to scrub through your timeline.

If you want to know more about all of these options, join me now in Sony Vegas and I will quickly show you exactly what I have been talking about.

Solution #6: Turn ON GPU Acceleration in Preference Settings

If you have a compatible Graphics Card, please make sure you have it turned on here:

Go to Options/Preferences/Video/GPU Acceleration of Video Processing

Compatibility

The information in this tutorial applies to all versions of Sony Vegas Pro and Sony Movie Studio Platinum.

Buy the latest version of Vegas Pro here !

About Derek Moran
Derek Moran is the author of all articles on Movie Studio Zen.
You can find me on YouTube, Facebook, Twitter, Read more about Derek...

Newest
- Best
- Popular
- Newest
- Oldest
Collapse All Expand All

You are a guest ( Sign Up ? )

or post as a guest

Loading comment... The comment will be refreshed after 00:00.

Your comment will be reviewed by a moderator before it is published on the site.
Michael Ziegler · 03:06 12/09/2021
One other problem is also when there is an orientation flag in the source file. Vegas tries to honor this on the fly resulting in awful lags in the preview especially when combining multiple videos (crop). Solution is to remove the orientation from the source file using exiftool (opensource) and adapting the orientation in the crop settings.
- {"set":null,"list":null}
- Reply
Your comment will be reviewed by a moderator before it is published on the site.
Andrew Johnson · 23:09 29/05/2019
Another tip that might work for some folks... Similar to what Derek suggests in the video... use something like Freemake Video converter (or maybe some version of FFMPEG) to convert clips to WMV. I was having preview-laggy MOV clips from my old Camera, but when converted to WMV, the lag seemed to be resolved. Also, I have a newer canon SX720 which saves MP4 files - but these don't seem to show the "preview lag" either. So it does depend a lot on the format/codecs that are used - but you all knew that!

Pre-rendering was also helpful, but can cause about 1GB or disk space to be taken up for every minute of pre-rendering, so make sure you set your Vegas temp directory to where you have enough space!
- {"set":null,"list":null}
- Reply
- Your comment will be reviewed by a moderator before it is published on the site.
  DoctorZen
  
  Member
  
  Moderator
  
  · 11:54 30/05/2019
  
  Never render to WMV - this is not something I would advise anyone do in 2019.
  WMV is highly compressed and VERY CPU intensive - it is not efficient to edit with on many lower powered computers.
  The inbuilt Proxy Creation Tool in Vegas is the simplest and easiest way to help the preview window play back smoothly. Yes you will need plenty of Hard Drive space. Most professional editors convert all there video to something like Cineform codec, which is very good to edit with. If you know the YouTube channel Linus Tech Tips, they convert ALL their videos to Cineform codec BEFORE they begin editing.
  MOV video is highly compressed and has always been a problem to edit with. Once again, I would advise to use the Proxy Creation Tool in Vegas to convert MOV video to an edit friendly format.
  
  {"set":null,"list":{"2":1}}
  
  Reply
Your comment will be reviewed by a moderator before it is published on the site.
Andrew Johnson · 21:49 29/05/2019
This is a really helpful tutorial, thanks. However, one has to wonder why Vegas doesn't just "play the video clips" like any normal media player would. Why does it need to "decompress" them and do complex computation, just for preview? Surely this ONLY needs to be done *when effects are added* or during rendering. It would really help if preview worked the same way as normal playback when no effects are applied... Similarly, video fades should not be computationally complex - not considering what Windows itself does with translucent windows in real time - on a PC with no dedicated graphics card... Just sayin'!
- {"set":null,"list":null}
- Reply
- Your comment will be reviewed by a moderator before it is published on the site.
  DoctorZen
  
  Member
  
  Moderator
  
  · 11:47 30/05/2019
  
  EVERY video editing program works the EXACT SAME WAY in the Preview Window - this is not unique to Vegas. When editing a video, each frame must be independent of the Frames on either side - this is what happens when it is decompressed in real time. When you watch a rendered video in a Media Player, information from previous frames is used to create the current frame. Just know that what is happening is very deliberate and ALL editing programs work the same.
  
  {"set":null,"list":null}
  
  Reply
Your comment will be reviewed by a moderator before it is published on the site.
Ninh · 20:40 28/10/2018
THANK LORD!!! I THOUGHT THE LAG IN THE PREVIEW ACTUALLY AFFECT THE REAL RENDER THANKSSSSS
- {"set":null,"list":{"2":1}}
- Reply
Your comment will be reviewed by a moderator before it is published on the site.
BEN! · 10:11 17/03/2018
THE PROXY VERSION WORKED FOR ME!!! THANKS MAN YOU ARE A GOD!!!!! IF I WOULD BE RICH I WOULD GAVE YOU 250 000$ CAD!!!!!
- {"set":null,"list":{"2":1}}
- Reply
- Your comment will be reviewed by a moderator before it is published on the site.
  Derek
  
  Member
  
  Moderator
  
  · 13:07 17/03/2018
  
  Cheers :)
  
  {"set":null,"list":null}
  
  Reply
Your comment will be reviewed by a moderator before it is published on the site.
John · 10:00 07/12/2017
BS. i5 + GTX560 = no lag ; i7 + GTX770 = MEGA LAG. Both Windows newly installed. Just video file without effects at all.
- {"set":null,"list":null}
- Reply
- Your comment will be reviewed by a moderator before it is published on the site.
  Derek
  
  Member
  
  Moderator
  
  · 15:17 07/12/2017
  
  The architecture of Nvidia graphics cards has changed over the years.
  All older versions of Vegas, fully support Nvidia graphics cards up to and including the GTX 500 series - anyone with one of these older cards will get good performance.
  GTX 600 and newer cards started to use a different architecture, which was not fully supported by Vegas, so for some media types you may see slower performance.
  Magix is now developing FULL support for ALL modern Nvidia graphics cards.
  Vegas Pro 15 now has a new encoder that 100% supports your graphics card - people are reporting very fast render times and good preview performance. Support for Vegas Movie Studio will be added when Vegas Movie Studio Platinum 15 is released next year.
  
  {"set":null,"list":null}
  
  Reply
Your comment will be reviewed by a moderator before it is published on the site.
Sanford

Member
· 05:56 11/03/2016
derek, thanks, please do a video on the use of the "Trimmer" function. sanford
- {"set":null,"list":null}
- Reply
Your comment will be reviewed by a moderator before it is published on the site.
Eagle Six

Member
· 03:59 11/03/2016
As always, meaningful topic and solutions. I think members and viewers will appreciate the follow-up link tutorials you provide as well.

Best Regards......George
- {"set":null,"list":null}
- Reply
Your comment will be reviewed by a moderator before it is published on the site.
Daniel Barraclough · 22:15 10/03/2016
Interesting new look to your videos Derek - thank you, but please please please drop the repetitive background loop music. Your previous tutorials, unlike many on youtube, are easy to follow without multitasking background noise.
- {"set":null,"list":null}
- Reply
- Your comment will be reviewed by a moderator before it is published on the site.
  Derek
  
  Member
  
  Moderator
  
  · 03:26 11/03/2016
  
  [b]I will be making some adjustments in the next videos to make the actual dialogue clearer.
  Thank you.[/b]
  
  {"set":null,"list":null}
  
  Reply