New here, having trouble determining FoV

[LionelD]

Hi, I'm new here, working with the trial version. My main goal at the moment is to embed large panos into iBooks as widgets.

I'm currently working with a pano stitched, straightened and leveled in PTGui, using the Cylindrical projection; it measures 14,922px X 4,974px, so it has an aspect ratio of exactly 3:1.

All I want the widget to do is enable the human viewer to pan left, right, up and down, and zoom in and out - seems to be very basic use of Pano2VR's capabilities. After some trial and error I have a widget, but it's not quite what I want.

Current behaviour in Pano2VR before building the widget
1. I'm not sure what information to provide by way of context for this, so I've attached the Pano2VR project file.
2. I can't zoom out far enough to see the whole image - zoom stops with about half the image visible.
3. I'd like zoom in to stop at 100%, but I don't understand what's going on here. I have Min FoV In set to 3px; if I set it to 1px, I can't zoom at all.
In short, I'm sure I have made some mistakes, but I can't figure out exactly what they are.
4. I find many of the FoV values quite mysterious, and that troubles me because this is all maths. Is there some detailed information I can read to understand how Pano2VR determines and uses these values? For example, if I load this image into a new project in Pano2VR, FoV in Viewing parameters is 31°; where did that come from? If I look at the map for this scene in Google Maps I conclude the FoV for the whole scene is about 90° (not sure what their projection is), which is my basis for setting this value to 94° (See attached screen grab with annotation).

Building the widget
I'd like the widget to open displaying the whole image; my MacBook display measures 2,560px X 1,600px; to fit, the image has to be scaled down to 2,560px X 853px (3:1).

For HTML output I've set the window size to 2,560px X 1,600px,exactly the same as my MacBook, and FoV Mode to Vertical.

For Transform output I have Type: Cylinder, Image Size 2,560px X 853px, FoV 94°. Not sure the Type should be cylindrical.

Widget Behaviour
1 On opening, my widget displays about half the image. I can zoom in and out, pan as desired.
2. I struggled with determining FoV for the Transform output, and ended up creating the Default.png image using Photoshop, and moving it into the widget manually. Every Default.png image from the Transform Output that I examined in Photoshop had a transparent border, with the image itself being smaller than 2,560px X 853px. I guess the FoV is not quite what I need to get the Default.png image to match my target dimensions exactly. Is there a way to calculate the required FoV, or a setting that forces it to match the target size?

Transform Output
I noticed that the Default.png image is set to 72PPI. Is there a reason for using this value? It should be irrelevant in this context because we're talking about displays, and retina displays have pixel density much, much higher - more than 300PPI in some cases.

I apologise for the length of this post, but really need some help please.

[LionelD]

UPDATE

Hi, I'm posting an update to reflect what I've learned, and a response from Martin.

First the easy part: I've learned that the iBooks.ggt has a mechanism that allows me to provide my own image for the Default.png. That makes all my related probems go away. Actually, it's better than that because, by using it, the P2VR project records more of what I did, and I really like that. I try to avoid relying on memory too much, prefer to have things written down in some form, somewhere.

Now the more complicated part.

My current objective remains the same: I want to embed large images in iBooks widget for inclusion in an iBook. Almost all my images are flat; I have one partial equirectangular, and it's quite likely the only such image that I have. The aspect ratios and pixel dimensions of my stitched images vary considerably, as you'd expect.

I would like the widget to display the whole image, and enable navigation and zoom in (to 100%) and out (to fit the display in use). I've continued experimenting to get this to work, and I've made a little progress, even though I do not understand exactly which of my changes has resulted in improvement. My experiments included a small set of variations using the same source image, but varying the Screen Size (HTML Output tab) and FoV Mode (Advanced tab). So now I have a somewhat improved understanding, and I'm beginning to connect settings to what the P2VR output looks like. The .ptvr file I attached to my OP is now out of date.

Martin has advised as follows by e-mail:

"The current version does not allow for borders to be shown, so a flat image will be cropped along the longest edge with the shortest filling the screen.
In beta 2 there will be a setting that will allow borders to be shown so the longest edge will fit the screen and the shortest will show borders.

The window size should be the logical screen size so 1024 x 768px, the same for the preview.png image.
Of course the iPad Pro will have a border around the edge as its larger then 1024 x 768px.

Remember the window size is the logical size and not the screen resolution."

So now I have to go read about adapting to different display sizes.

I must say that I did not appreciate what's involved in VR tours - there is much more to it than I thought.

I'd also like to say that, having made quite a few widgets manually, this is by far the easiest way to make a widget that I've found.

Martin, what are you able to tell us about when beta 2 and/or P2VR5.1 are likely to become available?

Finally, thanks for your response and assistance in restoring my forum access, it's much appreciated.

[Hopki]

Hi,
Pano2VR 5.1 beta 2, very, very soon
Pano2VR 5.1 final, I cant say for now, lets see what people find in 5.1 beta 2.
Regards,
Hopki