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Topic: Why is zoom not maintained in a Spin while navigating?

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NateLawrence (7 months ago)
Hello, Photosynth team,

I was wondering why you removed the ability to stay zoomed in on a particular part of the scene while panning around a spin.

Was this a pure design decision driven only by wanting to allow people to pan inside a single image when zoomed into a photo?

I ask because several people asked for this feature in the original Photosynth five years ago and it actually was present in Microsoft Research's original Spin demos in 2011.

Would you ever consider offering this feature as an opt-in toggle switch in the same way that you offer the two panning modes in stitched cube panoramas?

I do understand that this would mean that to zoom in on different parts of a single photo would require me to zoom out and then zoom in on the other part.

Perhaps a more elegant solution would be to support multi-finger swipes for panning while zoomed?
I support the idea of an option to remain zoomed in.
PhotosynthTeam (7 months ago)
We've got technical issues with offering this, based on how we feed the GPU at the moment, but beyond that it's an ask that brings up some tough design issues.  What's an example of where this would be particularly useful?
NateLawrence (7 months ago)
Oh. I knew that you guys were using low resolution versions of the whole photo while moving and then loaded in higher res with Seadragon when stopped at a photo, but until you said something here I hadn't thought too much about the fact that this feature would require preloading tiles associated with a particular region of the model (at least in a Spin's case) and having Seadragon running in between photos (or on a minimum of two simultaneously for crossfading at slower speeds) while the model is in motion.

Knowing which region of the point cloud the pixels which the viewport is zoomed in on should allow you to know which tiles to load in advance, but I'm guessing that it's the multiple DZIs being loaded up simultaneously that presents the performance challenge.
NateLawrence (7 months ago)
To your question of an example, though, I imagine you see your fair share of sculptures and statues in Photosynth. They provide an easy example.
If I want to zoom in on a statue's face (if this weren't compelling, why offer zoom?) and rotate through different angles (if this weren't compelling, why offer Spins?), I don't really want to have to zoom out every time that I want to move around or turn the object and thereafter try to zoom back in and get the same framing that I already had. 

I zoomed in on a region because it was interesting. 
I then want to turn the object because that's what convinced me to load the Spin in the first place.

It just runs completely contrary to the human instinct to examine something to move to a great distance from it every time you turn it over in your hand to see it from another angle.
NateLawrence (7 months ago)
I haven't thought too clearly about how preserving zoom would be useful in Walls or Walks...

Stitched panoramas already provide a reasonable case that zooming into a particular detail level and being able to continue to pan can be desirable  (not nearly so desirable as with Spins, though) and I expect this would carry over to both Walls and parallax panos.

Walks seem, at first glance, to be the potentially least valuable type of new synth to retain zoom throughout, although perhaps someone can enlighten me.
I do not think this is a question of usefulness, but a question of what one would expect naturally. So, to me it is a no brainer fundamental requirement. Nate puts it more nicely with elaboration. And I think I would not be tempted to use this feature in a Walk, but for the other three, surely yes.
@PhotosynthTeam. You have asked for an example of where it would be particularly useful. Maybe this could serve as such. Try reading the text on the pedestal of D'Artagnan. http://photosynth.net/preview/view/943fb8c3-e7fd-4d48-adf3-322b75ece294
NateLawrence (7 months ago)
It took me a while to track down a copy of Eric Stollnitz's talk at MIX11, but for those who are wondering what maintaining zoom in a spin while panning looks like, check out this short little YouTube playlist of two extracts from his talk: http://bit.ly/spinmovieszoomed

You can download the original video from Channel 9: http://channel9.msdn.com/events/MIX/MIX11/RES06 ('High Quality MP4' seems to be the only surviving video file)
or watch the entire mirror on YouTube here: http://youtube.com/watch?v=lGCoYVCzWT4&hd=1
NateLawrence (7 months ago)
I feel certain that I've read others' requests in the past for maintaining zoom while rotating around an object, but here's a request from GODLIKE, from back when Photosynth had been released 1 week, asking for maintaining zoom between different images in a panorama navigation point in an original photosynth which is essentially asking for maintaining zoom within a new parallax pano synth. 
https://getsatisfaction.com/livelabs/topics/click_drag_to_browse_panorama_no_autozoom
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