Can’t seem to get something to synth right? Curious about what lens is best? Ask your fellow Photosynthers here.
Do Photosynt compress the images before upload, and will a pre comression speed up the prosses (Precalc and upload)?
I can see a clear difference when i recompress the images from my camera (Canon eos450D) on my pc. (3.1MB -> 581KB). I can also see the uncompressed size is unchanged (28.8MB)
Is there a limmit on the resolution?
I tryed uploading 3880 x 2592 (10.1Mpix) some months ago, but the upload froze.
So now i just shrink them to 50%.
I've been uploading 4000x3000 images for a while. It does work, but typically I'll do big uploads on a broadband connection.
All my synths since late December last year have been composed of 3872 x 2592 images and I have no problems with it. Sometimes, yes, there are errors with an upload, but I don't believe they have anything to do with the size of the images because I would occasionally have them before I got my current camera.
What Photosynth does is divide each of your photos into several resolutions and divide each of those resolutions into a series of jpg tiles. I don't know what quality setting it's saving those jpg tiles at, but if compression is taking place, it would be here. Before these collections of tiles are uploaded to the site, they are zipped up (.dzi = deep zoom image; dziz = deep zoom image zip). You can test this the next time you're making a synth by typing %temp%/photosynther into Windows Explorer and copying (not moving) one of your dziz files out of the images folder. Add .zip to the end of the filename and you should be able to peek inside.
Out of curiosity, what did you mean by "I can see a clear difference when i recompress the images from my camera (Canon eos450D) on my pc (3.1MB -> 581KB)"? Do you mean a difference when viewing these images outside of Photosynth or a difference in loading time/quality after using them in a synth?
Also, where are you reading the 28.8MB size at?
Thanks for any answers.
I suspect if there is a maximum resolution for images it would be quite high, since I belive Photosynth uses the same deepzoomtools.dll that Deep Zoom Composer uses to convert images to the dzi format.
When i download the images from my camera, they r in jpg format, but low compression, when i recompress this images on my pc(open the pic, and save it again in jpg), they drop down to around 10% of the original. I recompress images before uploading them to save time.
I tryed ones to upload a 200MB jpg (29556 x 14321, 1.2gig uncompressed) from nasa, but ran out of memmory.
As to the big NASA image, yeah that's pretty hefty. I imagine that anything using the deepzoomtools.dll would be capable of completing the job but since everyone has a different amount of RAM installed, it's likely a bit difficult to estimate where the limit of how large an image you'll be able to convert is on your machine.
I still say photos straight off of your camera should do just fine. A 10 maegapixel image is a fair bit less than a 423 megapixel image. :)
It really would be nice to have something built in to Deep Zoom Composer and Photosynth that would read the installed RAM and give you an estimate of the maximum sized image that your machine is capable of converting and specific per-image warnings if that estimate's boundary is transgressed.