I doubt this will be of interest for most here but might help someone new to it all as I was a few months ago.
I didn’t want to spend much on a scaler but wasn’t sure what the best cheap option would be. A lot of the info around was very subjective and out of date. I ended up testing three:
Calibre Vantage-HD (2006) – I only paid about $7 for this, I think no one knew what it was and there were no other bids. It was over $3000 when new and uses the Silicon Optix Realta chip which apparently was amazing at the time.
Sony BDZ-AT350S (2012) – This one was about $20. Sony HDD recorders around this time made a big deal of their upscaling engine ‘CREAS’. This version, a low-end model, has CREAS 4. Later models had CREAS Pro and CREAS 5 which are supposedly better. After CREAS 5 they stopped mentioning the feature, I expect because people were by then more interested in playing native HD content.
Aerial UP EMPIRE 3 (2022) – About $50 new. This had fairly good reviews for a generic Chinese scaler and it claimed to maintain the original aspect ratio which most don’t.
As you can see in the below images the Vantage-HD is probably the best out of the 3 in most scenes with the Sony not far behind and sometimes better (especially when watching the video in motion). The Vantage is maybe over-sharpening but this can be tweaked. The Chinese box isn’t much good, the colors are off, the framing is weird and it’s generally soft. Interestingly there were no interlacing issues with any of them, dot crawl doesn’t seem to be bad and all are totally usable. Ignore the black levels, the overall brightness is a bit off on the HDMI capture box and needs tweaking.
I expect for many people the Sony HDD recorders would be a good option. Toshiba was also pushing upscaling tech at the time in its own recorders (it called it ‘XDE’). The Toshiba RD-X10 in 2010 was the latest and best player featuring this, it would be interesting to compare one sometime.
There are also some pro scalers that go for not much money and some switches with built in scalers. Generally, these seem a little less home friendly (no HDMI output, limited audio inputs, possible loud fans), but I’d like to see how they do.