In Photo AI 4, is there any quality benefit to sticking to even scaling factors divisible by 2 (like 2× or 4×)? My source material usually requires around 2.5× to 3× upscaling — 4× is often far too much, while 2× is slightly too little. Are the models optimized for clean multiples of 2, or is it just as safe to use intermediate values like 3× for high-detail drone and Nikon Z8 images intended for large prints?
For non-generative AI upscalers like Standard and High Fidelity there are only two scale factors, 2x and 4x. In your model folder there is a dedicated 2x model file and a 4x model file for each upscaler.
Other output resolutions are created by using a regular scaling algorithm on the AI ouput.
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Hi.
From your perspective it doesn’t make any difference how you scale the images by even, odd, or any fraction in-between and it’s good to ask because, if you Upscale the image by a factor of Two or Four Times even numbers it’s easy to think, Topaz Photo or Gigapixel and even Topaz Video is simply Doubling or Quadrupling the sauce material and interpolating the Pixels in-between which would result in the perfect Upscale and you would be right in thinking that as Alan so, rightly explained.
A little correction to the above information I mentioned Doubling and Quadrupling the sauce material for a simple explanation when in actual fact if you scale an image by Two Times Topaz is scaling the image size by a factor of four effectively doubling the pixel on both the horizontal and vertical so, Two Times is 2×2= 4× total pixel count Quadrupling 400% the image pixel count and Four Times is 4×4= 16× total pixel count Sexdecupling (if that’s a word) 1600% the pixel count.
Hang on a minute My Cockney Sparrow, what about increasing the image by odd numbers or smaller increments doesn’t that have an affect on the scaling.
Yes kinda, when you input a scale of Three Point Five for instance; Topaz will firstly scale the image by Four Times using AI then down scale the image back to Three Point Five using traditional scaling methods none AI now don’t panic this won’t impact image quality simply because, as we’re seeing you’re Upscaling the image not by 4× but, by an incredible 16× and to use the official terminology you have plenty of Wiggle Room to play with meaning, you, I, or anyone else won’t notice.
Therefore, you can scale your images by any factor you wish and the quality will remain the same regardless of the scale you input and besides, even if you print these large scale the majority of people will view these images as a whole to take in the entire Image some will view them up close but, won’t notice any irregularities Topaz Upscaling is superb.
Another example, I suffer from CDO it’s the same as OCD (Obsessive-Compulsive Disorder) but the letters are better arranged and hence, I spend a lot of time on this brilliant forum and don’t worry it’s not catching.
We use a Canon EOS R5 mark II with similar specs to your Z8 and usually when I crop an image I like to rescale the cropped images back to the original 45 Megapixel resolution just to keep our images consistent did I mention OCD so, I’m Upscaling by all kinds of of different odd inputs and fractions without any noticeable differences.
Technically Pixel Peeping Yes, Upscaling with even numbers will give you the absolute perfect results.
However, Upscaling with odd numbers quite frankly won’t make the slightest bit of difference it will still look perfect every time.
Hope this helps
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