I need to compare photos at a 1:1 pixel ratio (not downscaled to fit the monitor). For this, I need to set the view to 1:1 and then go through the photos using the arrow keys. As you can guess, I need the view setting to remain at 1:1 until I reset it, as with Lightroom.
Do iPhoto 11 and Picasa 3.9 on the Mac let me do this?
EDIT 1: This is not a Retina display. It's a 30-inch monitor at 2560 x 1600. And if I'm using a Retina display, I'd still expect the 1:1 to refer to physical pixels, no matter the pixel density. In other words, if I have a 2880 x 1800 photo, it should exactly fit the screen.
EDIT 2: To answer the question of why I am doing this, I am comparing cameras (iPhone vs NEX vs a superzoom) so that I understand exactly what the limitations of each camera are, under what situations (if any) I can leave the dedicated cameras at home and just use the iPhone, or if the superzoom gives me photo quality indistinguishable from the NEX.
EDIT 3: More information about why I'm doing this: The immediate goal is to help me decide under what circumstances the iPhone and the superzoom produce photos as good as the NEX.
This should help me decide when I can leave the other camera(s) at home and use the iPhone. Or whether I buying the aforementioned superzoom camera makes more sense for me than buying one or more zoom lenses for the NEX (each of which is as expensive as the superzoom camera).
I do not print out my photos. I view them full-screen on my monitor. So, if two cameras produce equivalent results when the photos are viewed full-screen, then I can buy the cheaper / smaller / lighter / more flexible option (like a superzoom camera instead of a zoom lens for the NEX).
The catch is that the best monitor I have today is 2560 x 1600, but I can imagine buying a 5120 x 2880 monitor. So, I don't want to choose a camera now and then realize later this year or the next year when I upgrade my monitor that my photos are not particularly good.
So, I want to compare cameras at 5120 x 2880. But my cameras take photos at a lower resolution, which is 4912 x 3264 for the NEX, and 3264 x 2448. So, I want to compare photos at 1:1 display.
(In an ideal world, if all my cameras shot at higher than 5120 x 2880, I would downscale all the images to this resolution and then compare them at 1:1. But since my cameras shoot at lower resolution, I want to compare them at 1:1. I don't want to upscale, since that reduces quality.)
Please let me know if this reasoning has a flaw. Thanks.