Re: Poor resolution issues producing HDR QTVR on PTgui 7,5 Pro Mac
- --- In PanoToolsNG@yahoogroups.com, "pra9matiste" <laurentsj@...>
"As aforementioned to Matt, i'd love to achieve this very quality
r=qt&id=21> ... in less than 3mb QTVR !"
Please note that Matt's high quality pano is 4.36MB in size, and it
really cannot be made smaller than that without significant loss of
The quality/size result you want is only possible if the content of
your particular scene permits it.
When working with a fixed cube face size of, let's say, 1908 pixels
AND a fixed JPEG compression rate, the QT or Flash VR-file of a
highly detailed scene will always be MUCH larger than that of a
rather featureless one.
For extremes think of a dense forest with overhead leaves and
branches vs a saltlake with a clear blue sky.
Filesizes for such scenes can be as small as 1.5MB and as large as
8MB with identical cubeface sizes (1908px) and JPEG compression (thus
To bring filesize down to an acceptable level compression has to be
increased, but then visual quality goes down fast as well.
An alternative strategy could be to make your cubefaces less detailed
by applying a Gaussian blur filter. This would make JPEG compression
more effective, so filesize will decrease.
But again you'll loose image quality!
What it comes down to is that you can't always get what you want,
you'll have to decide for each individual pano what is most important
to you: filesize or quality.
By the way: higher compression of larger cubefaces can give worse
results than less compression of smaller ones!
I used to make my fullscreen VR's from 2100x2100 cubefaces, but after
a lot of experimentation (and discussion) changed that to 1920x1920
AND less compression.
With (near) identical VR filesizes this usually gives me higher