Found lens spacer rings for cheap.

[NoDak]

Well I have been getting more and more comfortable with using the Chronos. However, one thing that continues to annoy me is how far away the minimum focus is, especially with how small some of the things I want to film are and not having the ability to use an HDMI monitor. Unscrewing the lens and spacer technically works, but reproducing your lens position is impossible and leaving your lens loose like that is an accident waiting to happen.

With my testing, it looks like adding 1.5-2.5mm of spacers with the Computar 12.5-75mm lens will let me focus down to 6-12" from the subject. The penalty in terms of image brightness is virtually imperceptible.

Some places online want several dollars per spacer. Thankfully eBay gives us more options.

https://www.ebay.com/sch/i.html?_from=R40&_trksid=p2380057.m570.l1313.TR0.TRC0.H1.XC-mount+Lens+spacer.TRS0&_nkw=C-mount+Lens+spacer&_sacat=0

I personally ordered some of the .5mm out of tolerance spacer rings from Singapore. Copper is soft enough that I'll be able to open them up slightly with my set of mini-files if I need to.

I figured I would post this in case others wanted to get some spacer rings of their own.

[Nikon1]

You can also Try Diopters.
Those can be Found on ebay from China for cheap.
You mount them on the Front of the Lens.
I use Small Spacers like those ones, you posted, or even some Spacers i cut out of paper or Plastic Foil myself.
And i Also use Diopters for some Things.
I found it good to have both options.
Cutting them out by yourself from Foil or Paper is a bit sketchy but works and is the cheapest option i found yet. You will maybe need to stack some of them then to get the prefered thicknes.

[CS223]

This was a big help to me for working close up. As a test I just unthreaded the lens a bit to get focus at the distance I needed. Since I have at my disposal a fiber laser I plan to cut out some brass .5mm spacers. My question is would there be any interest here from others wanting some and if so would C size spacers be preferred for between the lens and adapter or spacers to go between the C-CS adapter & camera or both?

[saichner]

Also... https://www.edmundoptics.com/?gclid=Cj0KCQjwka_1BRCPARIsAMlUmEqWK4zzf8znA-0wVt8ffDAdJXB5xE_PH1zWaO4X0tcpllaTZqebHdgaAiyTEALw_wcB

[ExperimentalPerception]

Wow, I'm glad i'm not the only one that has to unscrew the lens just a little to get the focus. I like the idea of spacers... always afraid I will unscrew the lens too much and forget about it and one of these days watch it fall to the ground

[Nikon1]

Still havent got my 2.1, but i am pretty sure, you can adjust the Backfocus on the Camera itself by loosening a Screw Somewhere and Reposition the Mount slightly to get perfect focus?
.
 You can for sure just add spacers, this will work, but there is a Propper way to adjust the Mount on the Camera to get the focus right. There should be some Explaination on the Forum Somewhere or on the Website / manual? not sure, if you cant find it, write a Mail to the Krontech Staff, they will explain how to do Backfocus Adjustment on the 1.4
.
Those Spacers are a better solution, if your lens Focus is off by a lot, or you try to use it for Closeup/ Macro beyond what the Manufacturer intended when Producing the lens. For Small adjustments, Backfocus adjustment on the Lens it self is usualy better and More Precise (Since Spacers only come in certain sizes, with backfocus adjustment you can set it to any distance you may need to achive propper focus).

[CS223]

The idea is to adjust your back-focus correctly for your lens and not have to bother it. Then use spacers to get the depth of focus you need for a particular shot.