So far, there is no 8x10 film sheet carrier that I can use
Some say get an anti newton glass but I dont want to sacrifice the quality because of extra layer of glass and cleaning dusts is another problem to deal with. Besides, the anti newton glass is extremely expensive.
There are a few 3D film mask but they dont hold the film and doesn’t do anything with making a film flat.
Are there any other solution for 8x10 film sheet tho?
Check out wet mounting.
If you buy a piece of anti-Newton glass manufactured by Schott, for example, there is no sacrifice of quality (I’ve tested it) and it’s probably the only way of making sure the film is flat, short of Digitizer’s suggestion to wet mount, which is doable but has some drawbacks - such as the need for the fluid, its application, cleaning it off afterward etc. A real nuisance. Nonetheless, if you want to wet-mount, you could use film cleaner. The advantage is also its drawback: it evaporates quickly.