SME mentioned- [quote]Another common one I've come across is right after the cel number there is a ' (apostrophe) symbol (example: A12'). These are also examples of key cels.[/quote]
I think the apostrophe-marked cels are partial layers or effect layers which are in addition to the sequenced sheets. I guess they are Keys too...
Are there tell-tale signs on a cel to hint if it's a Key cel? We usually see the Key markings on the douga but cels without the drawing, it becomes difficult to identify the 'higher quality' pieces.
I've looked at the painting quality of cels and sometimes think I can tell if it's done by a top animator or inbetweener. Am I fooling myself?
[quote]Are there tell-tale signs on a cel to hint if it's a Key cel? We usually see the Key markings on the douga but cels without the drawing, it becomes difficult to identify the 'higher quality' pieces[/quote]
Well . . . I'd say it's "higher quality" if you think it is. Frankly, just because someone's an "inbetweener" doesn't mean that he/she does inferior art. All it really means is that he/she has had less experience in the animation field. Japanese business is firmly founded on the idea of senority (a concept that even permeates their language through the use of sonkei and kenjou), though this has been slowly changing recently.
So, the way I see it, it really doesn't matter if the cel is key or not as long as you like it. I've seen inbetweeners that look just as nice as key cels. I've seen some that look horrible, too.
As far as being able to tell, your guesses are probably right. No matter how talented the artist, practice always leads to improvement. Yes, there may be some kouhai that can create some beautiful cels, but there are more sempai doing the same thing. I'd trust my instinct on that one.
As far as I know, there is no way to tell if the cel is not marked or you do not have the douga. Key cels are always done based on genga (one key cel per genga sheet), so if you have the genga, that could help. More than likely, if you don't have the douga, you don't have the genga, either.
From my experience, apostrophes on douga indicates a partial douga (usually the base character stays the same, so they combine the base douga and the apostrophe douga to save time). Apostrophes on cels indicate correction layers. Correction layers are also marked with the word kabuse (usually in katakana, sometimes hiragana).
