Zoom independantly and to greater than 100%

Started by DDBenson, December 04, 2013, 08:52:20 PM

Previous topic - Next topic


I use IM a lot to work with old family pictures (genealogy/family  history). I am often able to identify persons in old pictures by comparing them to known persons in other photos. To do this in IM3 I would select two or three or four photos and open them in the Side-by-Side viewer and then zoom each down to enlarge the subject faces to as large as possible or as large as necessary. I will zoom, zoom, zoom down on each of the selected files until the face in each one is the same size. Ideally I am able to enlarge enough to fill the entire space, but if not then I drag the faces to adjacent edges so that they are as close together as possible. Doing this with scans of old pics usually requires zooming down to much greater than 100%. The resulting images are often very grainy but I am able to effectively compare things like size and relationship of facial features and using this method has helped me identify many people in photos that I would not otherwise be able to do. Actually, I use this method to compare not just faces but many other things like windows or doors on buildings or trees in the background to try to determine the location that the photo was taken.

So far I have not been able to figure out how to duplicate this process in IM5. Using the file Viewer I can view multiple files, and by holding the Alt key while dragging I can independently move each of the images around within its space, but I can not zoom down any further than 100%. And I don't seem to be able to zoom independently on each file (that is to say that zooming with the "Ctrl-+" key combo zooms all files at once so that their relative size remains the same.) Is this a limitation by design or is there a setting to change that I have not yet discovered?


Currently the Viewer limits the zoom to 2x (200%). You can use <Ctrl> together with the <+> and <-> keys on the numeric keypad or <Shift>+<Wheel> to zoom in and out. I will increase the maximum zoom to 4x or 8x for the next release.

Zoom is always synchronous between all panels in the viewer.
-- Mario
IMatch Developer
Forum Administrator
http://www.photools.com  -  Contact & Support - Follow me on 𝕏 - Like photools.com on Facebook


Hello DDBenson, and welcome to the Forum.

I also do this job of comparing photos side-by-side, very frequently, but - although I've been an IM3 user for a long time - I have more recently been using the "donation-ware" program Faststone Image Viewer to do this.

I note Mario's reply to you above, and perhaps in a few month's time (when IM5 has had time to settle) I could add a post in the Feature Request forum here for more Side-by-Side viewer functionality ... but for now I'll cheekily continue with this note on how I use Faststone to do this.

To compare photos, I invoke Faststone with a mouse-click from within IMatch. This can send just one of the set of photos to be compared across to Faststone, from where I then need to add selected thumbnails (up to four in total), before opening Faststone's own side-by-side viewer.  So clearly, with Faststone we lose the immense power of IMatch's image-Selection features.  In Faststone, the images to be compared must all be in the same folder.

Both side-by-side viewers allow us to do what I would call an "occulting comparison", which I value hugely (although this may not have as much value in your context).  In other words we can quickly overlay one image on top of another image to make very fine detail comparisons.  Faststone is limited to just two occulting images (using one toggling mouse-click), while in IMatch we can quickly overlay any one of the four viewer panes on top of another image by pressing the CTRL key plus '1' or '2' or '3' or '4' (with a not-so-convenient mouse-click equivalent available too.)  This 'occulting' feature makes me drool, even thinking about it  8)

Both IMatch and Faststone can zoom both images "zoom-locked" or can zoom them independently.  IMatch 3's Side-by-Side viewer can zoom to 2000%, and Faststone's can go up to 5000%.  It's frustrating (to me) that each program has a built-in / pre-defined 'table' of fixed zoom-value steps.  It would be ideal IMHO if we could choose our own "rates" of zoom-increments, but I guess this isn't an easy thing to implement.

I'll bet DDBenson that you already know about Faststone Image Viewer (!?!) so I'll apologise for this long rambling reply.

I reckon that "image comparison" is very much at home inside a Digital Asset Management (DAM) tool like IMatch, but I also accept that it's not one of the tasks that need to be tuned in favour of the core DAM functionality.  Let's look forward (hint hint  ;) ) to when Mario can do some "de-burring" and "honing" in this corner of the toolbox.

Colin P.