I used IrfanView for years on a PC, was one of the first things I would install when setting up a new PC for someone so they could easily resize and rotate photos and stop sending those oversized photos in email. I looked at the IrfanView website to see if they had added much since I stopped using it and moved to a Mac. Not much has been added that I could tell. On a Mac Preview comes installed and is one of the most over look Apps on the Mac. I think when most people get their first Mac and double click on an image and it opens in Preview the say, "thats nice but it doesn't do much else" and start looking for something else to use like they had on their old PC. You have to remember you are on a Mac and things are different and you may over look and miss a lot of you try to make it work like a PC. I keep Preview on the dock because it is one of the most handy tools on a Mac for working with photos.
Here is a list I got off the IrfanView site.
Some IrfanView features:
▪ Many supported file formats (click here the list of formats)
▪ Multi language support Preview does
▪ Thumbnail/preview option Preview does
▪ Paint option - to draw lines, circles, arrows, straighten image etc. Preview Annotates with arrows, boxes, circles and text
▪ Toolbar skins option No
▪ Slideshow (save slideshow as EXE/SCR or burn it to CD) Preview does slide shows, but to save or burn use iPhoto or iMovie
▪ Show EXIF/IPTC/Comment text in Slideshow/Fulloes etc. Preview No, iPhoto yes
▪ Support for Adobe Photoshop Filters No
▪ Fast directory view (moving through directory) Preview does
▪ Batch conversion (with image processing) Preview does somethings like resize or rotate
▪ Multipage TIF editing Don't know
▪ File search Preview does
▪ Email option Preview does
▪ Multimedia player Preview No, Quicklook yes
▪ Print option Preview does
▪ Support for embedded color profiles in JPG/TIF Preview does
▪ Change color depth Don't kmow
▪ Scan (batch scan) support Preview does
▪ Cut/crop Preview does
▪ IPTC editing Preview does
▪ Effects (Sharpen, Blur, Adobe 8BF, Filter Factory, Filters Unlimited, etc.) Preview does Sharpen and Color Correction but no Adobe filters
▪ Capturing Preview does
▪ Extract icons from EXE/DLL/ICLs No EXE, DLL's or ICL's on a Mac
▪ Lossless JPG rotation Preview does
▪ Unicode support Preview ?
▪ Many hotkeys Preview does
▪ Many command line options No
▪ Many PlugIns No
▪ Only one EXE-File, no DLLs, no Shareware messages like "I Agree" or "Evaluation expired"
Preview is only one file, there are no DLLs on a Mac and of course no Nag scrseens
▪ No registry changes without user action/permission! No registry on a Mac
▪ and much much more Preview does PDF's as well as images
To open up the power of Preview I keep it on the dock so it is handy all the time (doesn't have to be open and running). Select the group of files you want to see or just drag the whole folder to the dock and drop on Preview. Preview will open with all the images in a side bar and some buttons will appear on the bottom right. One of these buttons is "Contact Sheet" when you click on it a Slider will appear on the bottom left and you can adjust the size of the thumbnails. By dropping multiple files on Preview you can now do Batch operations too, like Adjust the size or flip and rotate. You can easily Crop images and do Color Adjusts in Preview as well. I also use Preview to "Annotate" screen shots by adding boxes, circles, arrows and text when I need to. I try to use the features that came on my Mac when possible. I believe they were designed to work well together and I don't need to run a lot of 3rd party software to try and force my Mac to act like Windows machine. Don't forget that "Quick Look" also works well for browsing all kinds of files (images, music, PDF, text and etc). Open Finder in " List or Column view" select a file then hit the "Space bar" and then you can scroll up and down using the arrow keys.