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03/13/2023 07:20:01 AM · #1
I recently submitted an image - for the first time in a few years. In Lightroom, after resize, the image quality is superb. After export it still look great and is sharp, but my entry looks blurry and poor quality. It's been so long, so maybe I forgot how to resize for best quality in DPC. When exporting I use "longest side 1200px" and 240 pixels per inch. Image size usually ends up at around 5-600 pix, without me having to reduce quality.
Should I do it differently?

Message edited by author 2023-03-13 07:26:39.
03/13/2023 07:35:13 AM · #2
Happens to me but got used to it.

Check here and here
03/13/2023 08:00:21 AM · #3
When you export, are you constraining the file size to 700kB? Is that why you are actually winding up with a 500-600px image instead of 1200? If so, try this instead: reduce quality setting instead. While it may seem counterintuitive, you're far better off with more compression (which is what lowering quality does) than with less pixels.
03/13/2023 08:13:58 AM · #4
Thanks for responses!
I misinformed. I meant 5-600kb in size. Image is always 1200px. Sorry about the confusion.
03/13/2023 08:36:47 AM · #5
Pictures can look different once posted if your browser (or the site) is re-sizing the image to fit your screen rather than displaying at 100%.

Also, when I re-size a picture I'll usually make it a bit smaller than the 1200 maximum to let Photoshop work with "even" percentages. For example, my camera is only 2816px on the long side; reducing to 1200px is 42.61%, whereas an even 40% reduction takes it to 1126px. I suspect (but can't prove) that avoiding calculations involving fractions of pixels will preserve detail better.
03/13/2023 09:15:19 AM · #6
Originally posted by TrollMan:

Thanks for responses!
I misinformed. I meant 5-600kb in size. Image is always 1200px. Sorry about the confusion.


Ah, well that changes things then... if you are resizing to exactly 1200 on the long side, that is the optimal place to be. I will say that when I have had challenging images to submit, e.g. this one:



I have had to reduce quality quite a bit, but have not seen a big degradation in detail, beyond what is unavoidable result of reducing to 1200px. One thing you can try... export your image for submission, then open that image in a browser window (to do this on Windows, just drag/drop the file onto an open browser window). View this side-by-side with your submission. Are you seeing the same degradation in quality?
With respect to "even ratio reduction," I suspect that there is *very* little if any visual difference when the resizing ratio is not an integer. Nonetheless I do initially resize on a non-integer ratio so that my final resize is on an integer ratio. In Paul's example, I would resize first to 2400px, then to 1200. I would not submit at less than 1200. Using Paul's example again, submitting at 1126px means giving up 12% of available pixels on your submission; that's 12% of available visual detail.

ETA: fixed thread title :-)

Message edited by author 2023-03-13 09:16:16.
03/13/2023 10:19:18 AM · #7
Thank you to both of you - and for fixing my auto correct ("og" is the Norwegian word for "and"). I need to check better before submitting posts.

I did some testing and opened it in my browser. It was equally soft. I use Chrome on iOS. I also tried in Safari; also soft. My Mac is newest Macbook pro M1. I'm ok as long as I know it probably just is like that with some images through browser.

Thanks again, guys!
03/13/2023 09:57:04 PM · #8
After editing my RAW image in PS, I resize to 1200px for the long dimension, then I export/resize image to 700kb in "save for web" in PS. This seems to work pretty well - and I have not noticed any degradation in my image quality.
03/14/2023 12:30:33 AM · #9
It really is the combination of computer / web browser.

On both my iMac (5k) and MacBook (16in) on Chrome and Safari pics do not look good. The same pics look way better on my Surface Pro.

If I zoom out the browsers on the Macs to a 75% the pics looks better. Could be the way the PCs make use of their screens, I have no idea.
03/14/2023 10:46:58 AM · #10
Originally posted by Tiberius:

It really is the combination of computer / web browser.

On both my iMac (5k) and MacBook (16in) on Chrome and Safari pics do not look good. The same pics look way better on my Surface Pro.

If I zoom out the browsers on the Macs to a 75% the pics looks better. Could be the way the PCs make use of their screens, I have no idea.


It seems that MacOS is a common thread here. Wondering, can you display my entry linked above, screenshot the browser window, save as a .PNG and send me the file? I'd be interested in how that image is displaying on your system, and whether you see a significant quality difference when viewing it on the Mac vs. the Surface?
03/14/2023 01:09:33 PM · #11
On a positive note...

Are is back at DPC! Welcome back, Trollman!
03/14/2023 01:47:12 PM · #12
Originally posted by tanguera:

Welcome back, Trollman!

Yes, welcome back to my former arch nemesis.

On topic: I submit certain-to-be blue ribbon photos, but for some reason the quality of the voters degrades once voting begins.
03/14/2023 02:42:22 PM · #13
Originally posted by Art Roflmao:

...for some reason the quality of the voters degrades once voting begins.


Many of the voters, myself included, are well beyond their use-by date, so, you know, ymmv.
03/14/2023 04:50:39 PM · #14
Originally posted by Art Roflmao:

Originally posted by tanguera:

Welcome back, Trollman!

Yes, welcome back to my former arch nemesis.

Thanks! Been a while. I see you haven't aged well.
03/14/2023 04:51:21 PM · #15
Originally posted by tanguera:

On a positive note...

Are is back at DPC! Welcome back, Trollman!


Thanks!
03/15/2023 10:45:36 AM · #16
Tiberius sent me screen shots from both his Mac and his Surface tablet. I downloaded them and brought them up in Ps, looked at both the Mac and Surface versions at high magnification. It seemed like both had the same level of detail preserved.
I then did a side-by-side comparison with zoom levels set to match the displayed size. Once again, looking at them side-by side at the same magnification level, they do look the same to me.
What I suspect is going on perceptually is that the higher resolution of the Mac screen is resulting in the image being scaled up so that it can appear softer if the viewing distance is short.
FWIW, I am viewing on a 31.5-inch 4k screen, which is still a little under the resolution of some of the Mac screens (the 5k ones).
03/15/2023 02:17:49 PM · #17
Thanks for doing the tests. Interesting result. It is strange that it seems softer via any browser - or at least the two I testet with - than when it's viewed with iOS's "Preview". It's quite possible you're right, kirbic, that it has to do with slight scaling, although the image set to 100% in preview to my eye looks to be the same size as the one in the browser.
03/15/2023 02:30:36 PM · #18
So I did a test. I uploaded a pic, that I think is tack sharp, from my Mac to my portfolio. I then viewed it side by side with the image open in Preview. I then took a screenshot and uploaded it here. Now both images are softer, but you can see the difference. See if you can guess which one is viewed on DPC (it would've been the same if viewed with browser, so not a fault at DPC, as we've already determined).



EDIT: The entire image:


Message edited by author 2023-03-15 14:37:05.
03/16/2023 01:58:58 AM · #19
I wonder why DPC still has this minuscule size of images, why not increase it to at least 1920 and have no restriction on file size? These days disk space is cheap, bandwidth of connections large and most voters would have at least HD monitors (1920x1200).
03/16/2023 02:09:10 AM · #20
Originally posted by TrollMan:

Originally posted by Art Roflmao:

Originally posted by tanguera:

Welcome back, Trollman!

Yes, welcome back to my former arch nemesis.

Thanks! Been a while. I see you haven't aged well.

Just like your photos. hahahahahahaha! :P
03/16/2023 02:23:11 AM · #21
Originally posted by Art Roflmao:

Originally posted by TrollMan:

Originally posted by Art Roflmao:

Originally posted by tanguera:

Welcome back, Trollman!

Yes, welcome back to my former arch nemesis.

Thanks! Been a while. I see you haven't aged well.

Just like your photos. hahahahahahaha! :P


LOL. Guess I can't argue that :P
03/16/2023 04:25:12 AM · #22
Originally posted by kirbic:


What I suspect is going on perceptually is that the higher resolution of the Mac screen is resulting in the image being scaled up so that it can appear softer if the viewing distance is short.


+1
03/16/2023 11:29:32 AM · #23
And all this time, Apple had the answer .. :P



Message edited by author 2023-03-16 11:31:46.
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