Images in slideshows are pixelated/soft

[peyton]

Hi there,

This is a continuation of this thread from sometime ago: http://forums.camerabits.com/index.php?topic=9244.msg44999#msg44999

I am having an issue where, when viewing images in a slideshow, the images appear pixelated. The images appear sharp when only previewing photos (i.e. pressing the magnifying glass icon), however, the images are pixelated when viewing in a slideshow.  This applies to both JPEGS and Camera RAW (1DX) images.

I am on a 27" 5K iMac (5120x2880 resolution) running 10.12.2 (there is also an attached 2nd 27" monitor at 1920x1200).  I am using Photo Mechanic Version 5.0, build 18040 (9e75cf5).

If it helps, I attached a screenshot showing my settings for the "preview" section.

Thank you!
Peyton

[Hayo Baan]

My guess is that those images simply are too small to give good unpixelated output. What are the dimensions (in pixels) of the images that show pixelated? Note: for raw files the embedded preview is used and not all cameras generate this at full resolution (but I thought a 1dx did).

For a 5K display to show unpixelated images, they need to be at least 5120x2880 pixels. Anything smaller will show pixelated...

[peyton]

Hi Hayo,

Thank you for responding. That is a good point.  I should have mentioned that this issue also affects images from my Canon 5D Mk IV, which are around 6720x4480. I see both RAW and processed JPEG images affected.

Also of note, in the preview mode, in which the image fills most of the screen (around 90% of the screen), the image looks fantastic. But once I display it in a slideshow, it falls apart. 

I know of at least one other photographer who is having this issue on a 13" retina MacBook Pro (sorry, I'm not sure the exact resolution of his display).

Peyton

[Hayo Baan]

Are you saying then when you view the image in the preview window (unzoomed!) it does not exhibit the pixelation?

What is the image pixel size?

[peyton]

Hi Hayo,

Yes, that is correct. When I view the image in the preview window, unzoomed, the image looks perfect and exhibits no pixelation.  However, when I view that same image in Slideshow, the image is pixelated.  That disconnect is confusing; that is, why does it look perfect in preview (when the image nearly fills the screen) and not in slideshow?

The image pixel size is 6720x4480.  So if I display a portrait-oriented photo on my display, where the image is 6720 pixels tall and the display is 2880 pixels tall, there is obviously more than enough pixels to fill the screen.  However, even portrait-oriented photos, at least in the Slideshow mode, look terrible. In preview mode, perfect.

So this is not an issue of having a photo that is too small to display without pixelation.  There is something about viewing a photo in Slideshow mode that pixelates the photo. It is very confusing -- to me at least.

Thank you again!
Peyton

[Hayo Baan]

Hmm, that IS weird. It might be a bug in PM. Hopefully @Kirk can shed some more light on the situation here.

[Kirk Baker]

Not a bug, more of a deficiency.  In order to make the slideshow previews high resolution on high DPI screens, the slideshow would need to break up each image into four (or more) smaller images and tile them.  The video driver cannot handle a single texture (we're mapping the image onto a rectangular polygon) of the size sufficient to show the pixels at a 1:1 ratio.  Currently the slideshow does not do this.

I will try to do this soon, but I have a lot of other PM6 tasks to work on.  I will make sure that this is addressed in PM6 at the very least.

-Kirk

[peyton]

Thank you, Kirk. It is good to know it is at least on the radar with your team.

Best Wishes,
Peyton