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Quality and workflow

Posted: Tue May 01, 2007 3:06 pm
by gus
Hi all

Im fairly new at the pano-game, but have managed to succesfully produce some fairly OK-ish panos. Id like to improve my quality versus size of my pano, sensibly, as opposed to playing around with all the different combinations of sizes, tile sizes, quality etc.

My workflow is something like this:

1) Shoot 6 fisheye (peleng 8mm+D50) images in RAW ( i dont bother with nadir and zenith, I adjust the max and min tilt to avoid the holes)
2) Covert to TIF(lossless) after finetuning exposure/whitebalance with Nikon batch editor.
3) I then stitch the images into a 2:1 equirectangular TIF image using Stitcher 5, using smart blending and maintaining 100% size and quality. Its a biig file!
4) Finetuning is then done in Photoshop CS2, adjusting the sharpness, curve etc.
5)I then save this image as a JPEG, 4000x2000, using a quality of 10(out of 12), still quite a big file.
6) This is then the image I import into Pano2QTVR, to produce the final QT tour.
7) I adjust the quality of the image using the quality slider, say 90%
8 ) I then adjust the tile-size to 200 pixels bigger than my width dimension on final window size, ie if its a 800x600 pano, I'll make the tile size 1000. This is the part Im unsure off.
9) I set the static quality to max, and the rotating quality to max.

My questions are:

1)At what point should you convert TIF to JPEG? If at all?
2)How do you determine the tile size to be used, as this dramatically changes the size. Its worth noting that I like to limit my FOV to a max and min value, this prevents the user from zooming into pixelated area, and also, avoids zooming out to the extent where it looks funny when rotating)
3)At what point is it best to sharpen and denoise the image? RAW or in CS?
4) What is the difference in "auto" and "optimal" tile size in pano2qtvr?
5) What size does the 2:1 image have to be for a) full size pano, b)800x600, c)400x300. Is there a method of determing the relationship. It seems like a waste of pixels to use a 4000x2000 image for a 400x300 movie?

If the users can share alternative workflows that produce good results, Im sure there's a lot of us that can benefit!

Thanx in advance!

gus 8)

Posted: Tue May 01, 2007 5:05 pm
by 360Texas
We use Canon 5d, Sigma 8 f3.5 RAW .cr2

Shoot 4 on horizon, tilt up 90 deg take 1 zenith shot
Convert RAW to TIF 16bit 25mb each image
Stitch all in PTgui output 16bit TIF 2000 x 4000 40mb
Use Pano2QTVR to cube image 6 face tiles
Patch Nadir (bottom tile) to remove tripod cap
Convert cube back to 2:1 equirectangle
Using 1264 tile sizes - individual tile compression 50,50,50,50,30,30
Convert to either QTVR or Flash 1.5mb for broadband

On most projects we do not use .jpeg

Hope that helps

Reducing size

Posted: Tue May 01, 2007 6:27 pm
by gus
Hi Dave,

Thanks for sharing your workflow.
Interesting to see you dont bother with jpg at all. I'll try that, and reduce the compression to 50,50,50,50,30,30 and see what I get.

Any more ideas .......anyone?


Posted: Tue May 01, 2007 7:47 pm
by 360Texas
for the UP sky shot tile you need to watch for over compression. Example, if you make the sky shot compressed 90 there is very little compression.. sky is smooth. BUT the overall .mov or .swf will be around 2.5mb too large for the internet.

Make the compression 50% and sky is smooth and file size is around 1.9mb still too large for websites. Make the sky 10% (high compression) and the sky will turn blocky and contain undesirable artifacts. File size is around 800kb which is good but bad blocky looking sky. INcrease the sky tile 5 to about 30% and managable .swf or .mov size 1.2mb.

Another way to reduce the over file size is to change the tile size itself from say 1246 to around 1001, or 901 pixels square tiles. Its a combination of getting the proper .swf or .mov file size by changing tile face size and applying % compression amount overall or by individual tile face %.