[ptx] Image resolution of stitched images

[Carl von Einem]

Hugin doesn't degrade resolution as you might think, Image resolution is 
only a relation (DPI: Dots per Inch) and is neccessary to show the size 
you will get on your output medium.

In Photoshop's menu Bild: Bildgrösse... (menu Image: Image size) just 
deselect "Bild neu berechnen mit" (= Interpolator drop down menu) and 
choose the dpi number you need for your output device (printer ~300 dpi 
/ screen 72 or 96 dpi, etc.). You will see that the actual amount of 
pixels won't change whatever dpi number you type.

The resulting size of your pano depends on the FoV of your camera's 
lens: a shorter focal length (e.g. 28 mm instead of 35 mm) leads to a 
smaller number of pictures you will need for a panorama but also gives 
you less pixels per degree.

So if your print @ 300 dpi doesn't show a big enough pano you have to 
either shoot your pano with less FoV per picture (35 instead of 28 mm) 
or choose a camera with even more MP.

Does that help?

Carl
(Munich, also Germany)

Philipp B. Koch wrote:
> I have a question about the image resolution of images being stitched 
> with Hugin. Since I haven't found this topic in the mailing list 
> subjects, I hope it has not already been dealt with.
> 
> My source images (made with Nikon Coolpix 5400) are 2592 x 1944 pixels 
> (= 5 MP) of size and their resolution is 300 pixels/inch when being 
> opened in Photoshop. After stitching them together with Hugin, image 
> size (both pixel measures and printing size) is pretty huge while 
> resolution is only 72 pixels/inch. For example: The original image 
> printing height (source images) shown in Photoshop would be 16,46 cm at 
> 300 pixels/inch -- the stitched images have a height of 71,12 cm at 72 
> pixels/inch. This is a problem because printing them shows bad results 
> (ugly small squares in the image caused by low resolution). First I 
> thought, this might be caused by Enblend, but already the result images 
> (flatened TIFF using PTStitcher, no color/brightness correction) 
> generated by Hugin are like that.
> 
> How can I avoid Hugin from setting down image resolution? What am I 
> doing wrong?
> 
> Thanks, Ph.Koch (Berlin, Germany)
> 
> ___________
> I'm using: Hugin 0.5 beta3 on Windows XP Prof; Autopano 1.30 (A. Jenny); 
> Enblend GUI 1.0 (E. Boyd); Photoshop 7
> 
>