Canon FD lenses are indeed very famous in this moment.
But one of the very best FD's is not popular at all.... it's real hidden gem: the 50mm f/3.5 Macro!

I own set of 14 FD primes in all focal lengths between 17mm and 200mm. I don't know if I am just lucky to own especially good copy this lens, but it kind of outperforms almost all other FDs I have. I find it just indispensable.

Nobody wants 50mm f/3.5 lenses today, so one can buy it for next to nothing, if just a bit lucky. Straight from maximal aperture onwards great IQ: no flare, no ghosting, no CA, razor sharp all over, good colors rendition. Its optical elements are as small as Panny 20mm/1.7's
This is the one:

I haven't shot any real footage with it yet, but I find the Tamron Adaptall 80-210mm f/3.8-4 a fabulous performer in the bargain basement range when shooting stills. I've compared it to a 70-210mm 19AH SP Adaptall-2 in some not-very-controlled comparison tests on my Pentax k100d Super for stills, and it performs quite admirably in comparison- and it's so much lighter and easier handling.

Used it in some closeup work on a quick and dirty test when first got my hands on a gh2, and footage matched up very nicely with that shot with a Pentax M 50mm f/1.4.

I've seen it in the $10-$35 range depending on condition/seller: Mine came in a job lot with some other fantastic lenses for 80 bucks, so I'd have to say I paid ~$25.00, but it wasn't why I grabbed the job lot, believe me! (Pentax K 55mm f/1.8 and M 35mm f/2.8 were the big attraction).

Details here: http://www.adaptall-2.org/lenses/103A.html

I'm sure you are right, that it is the first two digits, I just happen to have two that start with triple 777 for some reason. What I mean by my comment is that I have tested quite a few of these legacy zooms, and I have found the Koburi to have better color and sharpness, for lenses that cover a similar range. None of them is as sharp as something like a Leicasonic, but they have a big range and are cheap.

@DrDave

In fact, if you look at first page, serial begins with 77, and it is first two digits that show manufacturer, not three.

So, I still do not understand remark.

The Kobori 28-200/3.5 is a much better lens for this particular range

What do you mean under it.

As Vivitar is just brand name, so it can be exactly same lens.

@vicharris

I tested two copies of Soligor 35-140mm. One is parfocal from 35 to 105 and the other is not. I just don't know why.

Anyone know of any gems in terms of a wide angle that will match the image type of my Lomos (50mm & 28mm)? Thinking something between around 14-16mm, but maybe more or less. I Don't want a Lomo as the wide ones are soft. My main goal is to get a wide that has the same image type of my other Lomos so they match when editing footage shot with the different lenses. Any gems?

Ha, talking about great russian lenses almost forgot this one: Helios-103 (53mm f/1,8). Comparing its price with performance, it's a real hidden gem.

The only two drawbacks are:
1. I never saw yet an adapter for MFT, the only mount this lens was made for is the old Kiev/Contax bayonet, I think. I bought from some russian guy via eBay his hand-made adapter which works great
2. this lens has no multi-coating which makes it prone to flare and ghosting. With hood it performs like champion.

@apefos Thanks! I just bought the Soligor 35-140. Like the idea of parfocul! Does that Vivitar zoom keep focus through the zoom as well?

I have a channel on vimeo showing shoots with different vintage lenses:

https://vimeo.com/channels/lenstest

ok Vitaliy will do!

The Navitar 75mm f1.3 CCTV lens is a hidden gem. I had one, shot quite a few films with it, but eventually sold it cos I thought it was a 1 inch lens, and not future proof. I could be wrong, seeing that C mount could some day make a comeback, especially now with contraptions like Digital Bolex looming on the horizon. Those who are able to locate one should try it. Luminous lens that yields hairline sharpness, and yet the images are filmic.