I need explanation of some PTE menu choices...

[goddi]

Greetings...

I have been creeping along learning some of the more advanced things we can do in the new PTE. I am pretty happy with some of the progress I have made. But now I have come to a brick wall with some of the menu items. I have looked them up in the User Guide but it does not say 'why' I what to use then and what they actually do. I have also searched the Forum but I've not been successful. I have played around with them but it is not intuitive enough for me to see why/when I should use them and what they do. Here is a list of the ones that currently have me baffled.

I'd appreciate it if someone would clue me in on why/when I should use the following menu items and what they do:

-Perspective correction for Zoom

-Transparent to Selection

-Time Range

-Mode/Fit to Slide

-Mode/Cover Slide

-Mode/Original

Thanks... Gary

[fh1805]

Hi Gary,

I'll deal with just one of them in this post: Transparent to Selection

Let's assume you have three objects overlaid on a main image. You have zoomed them down to 50% size and positioned them so that they overlap one another to a very great degree. You now want to make a change to the lowest one.

If you try and select it with a mouse click you may find that one of the other two actually gets selected because it is on top and directly under the mouse pointer when you click. To get around this you make the top two objects transparent to selection. Now when you mouse click it will be the lowest object that gets selected.

It's a setting that you will use infrequently and you will probably turn it off immediately after doing the changes. But it can save a lot of frustration!

[davegee]

Mode:

Let's say, for example, that your monitor aspect ratio is 5:4 (1280 pixels wide and 1024 pixels high) and that you are using FULLSCREEN and 5:4 as your Screen Options.

If you add an image which has an aspect ratio of 3:2 (same as a DSLR) and pixel dimensions of 1680 pixels wide and 1120 pixels high you would see the following:

In FIT TO SLIDE Mode the image would show (in Objects and Animation) being fitted to the WIDTH of your screen area with blank space at top and bottom. (If the image was 1680x1120 in PORTRAIT format it would be fitted to the HEIGHT of your screen area with blank spaces at left and right sides).

In COVER SLIDE Mode the image would show (in Objects and Animation) being fitted to the HEIGHT of your screen area with overlapping areas to the left and right sides which would not show in PREVIEW. (If the image was 1680x1120 in PORTRAIT format it would be fitted to the WIDTH of your screen area with overlaps at top and bottom i.e. in either case it would COVER the screen).

In ORIGINAL Mode there would be OVERLAPS on all sides because the 1680x1120 image would be BIGGER than the screen resolution of 1280x1024. I like to think of ORIGINAL as the equivalent of ACTUAL PIXELS in Photoshop. (If your image was 1680x1120 in PORTRAIT format you would see blank spaces to the left and right of the image and overlaps at top and bottom because the image would then be TALLER than your screen resolution height but NARROWER than your screen resolution width).

Please note that in both FIT TO SLIDE and COVER SLIDE Modes (using the above resolutions and image sizes) your image would be INTERPOLATED DOWNWARDS to fit or cover the screen by PTE. In the case of COVER SLIDE Mode and PORTRAIT Format (using the above screen resolutions and image sizes) the interpolation would be UPWARDS to fit the width of the screen in PTE.

In the case of ORIGINAL Mode no interpolation would take place.

Interpolation DOWNWARDS in PTE is acceptable but UPWARDS in PTE is not desirable. (But that's something for another discussion).

DaveG

[fh1805]

DaveG,

Thanks for that wonderfully simple, clear explanation. I know you've posted on this subject in other threads but I've never fully understood things until now. It seems to me that the options would be better titled FIT TO SCREEN and COVER SCREEN or FIT TO MONITOR and COVER MONITOR in the English language as these better describe what they actually do.

[fh1805]

Gary,

Time Range

For each object, these two fields show the time offset (in milliseconds) into the entire sequence associated with the first and last keyframe for that object. Those keyframes might be the actual keyframes programmed by the user or the implied default keyframe that coincides with the end of the main image. The two fields allow the values to be changed by direct key entry or by using the Up/Down arrows. But having dabbled a little bit with them I cannot see what effect I am having by changing these values.

Would someone with more understanding than myself please explain this function? I can understand the benefit of being able to see the start and end times of objects relative to the whole sequence as well as their start end and times relative to their main image. But I do not understand why I would want to change these values using these two fields.

[goddi]

I'll deal with just one of them in this post: Transparent to Selection

Peter, I have run across this problem of selection and I did not know of an easy way of dealing with it. Thanks so much for the explanation. Gary

[goddi]

Mode:

DaveG

DaveG...

I think the reason I had difficulty seeing what was going on is that I always set my Screen to be about 95% so that I always get a boarder around the slides and the images were mostly landscape. I usually do not like the full screen effect. I tried changing the Mode settings with the Screen set to 100% and I now see what you are talking about. And I see that Cover has a bigger effect with portraits. Thanks for the help... Gary

[goddi]

Time Range

What threw me was that the ending milliseconds for one slide was not the beginning milliseconds for the next slide. The difference I see now is the 1500 milliseconds of fade in/out time. So I sort of see what is going on here but I don't think I will touch these settings until someone can shed more light on why I would want to make a change in these settings in the Time Range menu. Thanks. I do see it more clearly now... Gary

[goddi]

I am getting a great education here. Any takers on Perspective correction for Zoom?

Gary

[fh1805]

...I always set my Screen to be about 95%...

Gary,

Do you mean that you use O&A Zoom values to reduce the slde size to 95%? If so, have you thought of setting your images against a coloured background that fills the screen? It can look much more pleasant than showing them against a plain black background.

[davegee]

Lin and Jeff's guide says:

"The "Perspective Correction for Zoom" block lets you essentially simulate a movie camera zoom. It's best to experiment with this along with linear and non-linear zooms to get the desired effect"

It's to do with the way we "see" when a zoom is applied - without the Perspective Correction the zoom is linear and therefore unnatural. With the Perspective Correction it is non-linear and more natural to the eye. Slowly at first , then faster as we zoom in. Or is it the other way around?

I we ask Ken VERY nicely I'm sure that he can point us to the original thread which brought this function into PTE?

DaveG

[fh1805]

Gary,

Perspective Correction for Zoom

Try this thread from earlier this year: http://www.picturestoexe.com/forums/index....erspective+Zoom

[fh1805]

DaveG,

Two minds think alike...but I managed to find it myself!

[Ken Cox]

DAVE - i feel guilty after your accolade - i checked my faq's and did not have the link

but it is my files now

thks for jogging me

ken

[goddi]

Gary,

Do you mean that you use O&A Zoom values to reduce the slde size to 95%? If so, have you thought of setting your images against a coloured background that fills the screen? It can look much more pleasant than showing them against a plain black background.

To put a frame around my slideshow, I use the Project Options/Screen tab and change the '% of the slide to show main image' ti 95%. Then I choose Background/Gradiant filling and select a color for the top and one for the bottom (anc then Set for existing slides). Yea...more pleasant than black and can give some 'emotion' to the show, I think.

Thanks... Gary

[goddi]

Gary,

Perspective Correction for Zoom

Try this thread from earlier this year: http://www.picturestoexe.com/forums/index....erspective+Zoom

Thanks, Peter and Dave... I was using Smooth with my Zoom so I did not pick up the difference when I added the Perspective Correction for Zoom. After reading the thread and playing with it, I now see what you all are talking about. It is a nice touch to play with the custom settings too. Thanks all for your help... Gary

[Lin Evans]

Hi Dave,

Just a minor correction. The zoom may be linear or non-linear without perspective correction. Smooth, accelerate and decelerate (slow down) are all non-linear zooms as is perspective correction. Linear zoom begins and continues at a speed determined by the time duration between keyframes for the start and end of the zoom. Decelerate (slow down) begins fast and slows continually as the zoom progresses. Accelerate begins slowly and continually speeds until the end of the zoom. Smooth begins slowly, accelerates to a speed determined by the time between keyframes then progresses until near the end of the zoom at a linear rate then slows for the stop.

Perspective correction attempts to mirror a zoom such as you would get with a movie camera in which for a zoom out large subjects appear to start slowly then as the image gets smaller the speed appears to accelerate. Conversely, when zooming in small objects appear to first zoom quickly then the perception is that the zoom slows as the object gets closer.

By the way, see page 38 and page 61 in Jeff and my user guide for an explanation of Transparent to Selection and Ignore Objects Not Selected respectively.

Best regards,

Lin

Lin and Jeff's guide says:

"The "Perspective Correction for Zoom" block lets you essentially simulate a movie camera zoom. It's best to experiment with this along with linear and non-linear zooms to get the desired effect"

It's to do with the way we "see" when a zoom is applied - without the Perspective Correction the zoom is linear and therefore unnatural. With the Perspective Correction it is non-linear and more natural to the eye. Slowly at first , then faster as we zoom in. Or is it the other way around?

DaveG

[sanewcomb]

Perspective correction attempts to mirror a zoom such as you would get with a movie camera in which for a zoom out large subjects appear to start slowly then as the image gets smaller the speed appears to accelerate. Conversely, when zooming in small objects appear to first zoom quickly then the perception is that the zoom slows as the object gets closer.

Lin,

You have this reversed. To keep it straight I like to think of it as what you would see if you were looking out of the bottom of a rocket lifting off from earth. Ignoring the acceleration of the rocket, the image (ground) using "Perspective" Correction would change rapidly at first, and the higher you got the smaller the change would be.

BTW, the difference has more to do with the behavoir of programming algorithms than human perception or even the perspective and I tried to convince WnSoft to use a more appropriate name. The typical percent zoom algorithm actually gets the real world physics backwards which leads to a lot of confusion. But I give them lots of slack since English is not their first language.

Steve Newcomb

Tucson, AZ USA

[Lin Evans]

Hi Steve,

You're absolutely right. I should have explained that the "perception" part comes from "perspective correction."

The "perspective zoom" when zooming out starts fast and slows and when zooming in starts slow then speeds up near the end of the zoom.

The "perception" of a linear zoom is that when zooming out, as an object gets smaller it appears to accelerating in zoom out even though the actual rate of change is linear. As an object grows larger and closer it "appears" to be moving toward the observer more slowly even though it really is changing size at a linear rate. So the "perspective" zoom "corrects" for our perspective by reversing this process. At least that's the way it appears to the human eye in most cases.

Best regards,

Lin

Lin,

You have this reversed. To keep it straight I like to think of it as what you would see if you were looking out of the bottom of a rocket lifting off from earth. Ignoring the acceleration of the rocket, the image (ground) using "Perspective" Correction would change rapidly at first, and the higher you got the smaller the change would be.

BTW, the difference has more to do with the behavoir of programming algorithms than human perception or even the perspective and I tried to convince WnSoft to use a more appropriate name. The typical percent zoom algorithm actually gets the real world physics backwards which leads to a lot of confusion. But I give them lots of slack since English is not their first language.

Steve Newcomb

Tucson, AZ USA