Create and Use a "Knockout" Master Slide


A new version of this blog, which is valid for more recent Captivate releases (up till 11.5) has been posted under the link:


This question appears regularly on the Captivate forum: how can I insert captured slides in a master slide that has a logo and other information on board. Perhaps this small tip with a step-by-step planning can help you achieve your goal. Some images are attached to explain the workflow. And you will need some maths (you know probably already that I'm a maths-lover) but I'll provide you with a simple rule.

Work Flow

For this example I wanted to create a master slide to have a final SWF with a resolution of 920x600 pixels. The captured slides were created with a resolution of 640x480pixels, which left enough space to be filled with logo, text, etc.

Step 1 (in Photoshop or other app) - create the Knockout 

I created an image to be used as master slide. I created such an image in Photoshop but any program that allows you to have transparent pixels will do. This is the first image in the attached gallery. It is exactly 920x600pixels, has left a bar with a width of 200pixels, at the top another with a height of 70 pixels, to the right a bar with a width of 80 pixels and a the bottom a bar with a height of 50 pixels. The transparent region is exactly 640x480 pixels. In the image this transparant region is white.

Step 2 (in Captivate) - first rescale

Some maths to start with:
  1. calculate the difference between the widths of the vertical bars:     200 - 80 = 120 pixels
  2. new width project will be 640 + 120 = 740 pixels
  3. calculate the difference between the heights of the horizontal bars:   70 - 50 = 20 pixels
  4. new height project will be 480 + 20 = 500 pixels
Rescale the project using these settings:
  • deselect 'Maintain aspect ratio' and introduce the new dimensions
  • under 'New Size is Larger', select 'Keep project the same size and position project Bottom Right; I choose this because the bottom bar and the right bar have the smallest dimension;
The original captured size and the size after this first rescale are visible in the second and third image of the Gallery.

Step 3 (in Captivate): second rescale

 Rescale now to the final size, for this example to 920x600 pixels, with those settings:
  •  deselect 'Maintain aspect ratio' and introduce the final dimensions
  • under 'New Size is Larger', select 'Keep project the same size and position project Center
The fourth image in the Gallery shows the situation after the second rescale of the project.

Step 4 (in Captivate): apply master slide

Go into the Master slide panel and import the Knockout image either to the Library or immediately to the slide. Be sure it is positioned at X=Y=0 (Properties panel). Apply the Master slide to the captured and rescaled slides. The last image in the Gallery shows the result.

The Gallery is not really showing the image as I posted them. The white space that is added after the rescaling has partially be trimmed, and the difference in total size is not visible because all images are rescaled automatically. I'm very sorry about that, should move over to a better blog hosting.

Please let me know if this kind of small tip is useful, and do not hesitate to give me suggestions.

12 responses
This is a great tip! I don't have Photoshop though. :( Can you suggest any alternate options or opensource programs that will do the job for step 1?
I think this is a great idea, but I can't quite get it to work. I've created the knockout image, but when I apply it to the master slide it totally covers my capture. On the other hand, when I apply the image to my capture slide directly it works just fine. Is there a setting on the master slide that I'm missing?


Thanks, I'm glad the idea is useful. Check in the settings of the slides where you apply the Master slide that both 'Master Slide Objects On Top' and 'Use Master Slide Background' are deactivated. For Stage keep 'None' and Project Background must be checked. Normally you will see then in the Background filed the background from the Library that was created while capturing. It is better not to merge the knockout image to the background in the Master slide, contrary to what I told in the posting. Will correct that ASAP. Thanks for pointing out your issue, it pushed me to check again.
That did the trick, but now I'm having another problem. I recorded a rough demo of my company's software and am now running into the following issues:

1. After resizing the original project from 1024 x 768 to 800 x 600, my Typing Text objects remained in their original size and position. This is not a big deal, I can delete those, but I'm not sure why it's happening.

2. After resizing the second time to add my left and bottom borders (800 x 600 to 825 x 625 leaving the capture the same size and positioning it at Top Right), my clicks are misplaced and some of the capture backgrounds change positions during a preview and after publishing. The strangest thing is the slides in the project itself look right.

3. Finally, after the third resize (825 x 625 to 1024 x 768 leaving the capture the same size and positioning it at Bottom Left), the same issue as above occurs, but the clicks and backgrounds have moved once again. It's almost as if some slides are resized and repositioned correctly and others are not. What I end up seeing after a few slides is a sort of mixed up collage of my bagrounds with clicks where they should be...but on top of pieces of other backgrounds.

Does this sound familiar? If not, I'm sure it's really hard to imagine what this looks like, so I can send you a zip of my project and outputs if you'd like.

Thanks for all your help.

First question: did you install the patch that was released in December 2010? It solved some shifting while rescaling. I did try out this workflow and did not have those issues, so you could perhaps contact me on the user forums, send a private message with the link to the files (for and after rescaling) and I will check them out.
The patch did the trick. Thanks.
I have a bigger problem :)

I need to import the powerpoint sides so that I get the TOC and I need to put video in for each side. Normally I would simply put the video on top of the TOC but the size is not large enough for the client. The client also wants a backgroup that provides a knockout for the ppt and the video of the person doing the talk along.

I had done the ppt import at 600x480 to get the ppt and TOC interactivity, but I can't get the master slide background with my knockout to show behind the ppt import because IT IS THE BACKGROUND, DOH!

Would you have a work around?

Could you try this: apply the master slide, uncheck 'Use Master Slide background' and check 'Master slide objects on top'. Be sure not to merge the knockout image on the master slide with its background. Checked this out and seems to work.
I really appreciated this blog. It has helped me with a new project and things look so much cleaner now. I am wondering if you can help on Quiz Reporting and in the email subject line having the subject be the name of the CBT? Or if reporting to an Internal Sharepoint Server is possible?
Hi Lieve, I followed these instructions and had a great result, thank you for that! Now I have a question though. I need to make a change to the master slide due to which the transparent area moves to another location on the slide. Is there a way to reposition the background image (captures) to that new position? Because I can't post screenshots here I have also submitted this question with the screenshots in the Captivate community. Thank you! JP
After a night sleep I managed to do it. - made the project larger with a rescale and position everything in the top left (so got a white bar at the bottom. - Added the new background. - Did a rescale again to the original size with the crop setting. This also turned out well for all 'scanner related' objects as they were still positioned on the correct spot of the scanner image, but I had to move all other objects down slide by slide.
1 visitor upvoted this post.