Thanks for such a quick reply.
Good answers to unasked questions. Currently doing mostly nature shots
so few rack focuses, mostly in one direction. I can see dialog would be
more demanding on repeatability. Cine lenses, even used, cost more
than my camera.

So the FF ring might be waste of money until I get a real cine?

Also, are you using a flip device? Thinking of getting one but
$550-$600

FYI: my DIY rig is based on Canon's Ee-S screen.

Mostly telephoto then?

There will be some trial and error unless stopped down.

The FF ring will help, but it needs a Follow Focus setup (rod and matching gears) to go with it (not cheap if good).

Some cameras flip in-camera now, so personal choice.

Are you using a 24x36mm SLR focusing screen? That gives you DOF in droves if you use the full frame, but how's the picture? Wouldn't have thought that's so hot due to weight and different design choices perhaps?

Seems to me a better solution is EX3 + Nikon adaptor + Nikon 80-200mm f2.8 zoom. That extends the stock lens to just over 1000mm. Longer is easily done but from the shots I've seen you start to need serious tripods and heads.
Bob.

Using only a 50mm so mid of range I'd like.

My camera does not so I flip the image post in Vegas. Makes framing a pain.
Yes, the working area of the screen is 24x36 (bigger by about 2mm with locating
pins).

I am using this holder:


The tubes, Nikon F lens, holder, motor, and step up makes camera front heavy
without doubt. Rails are a must.
Image looks great with motor not spinning. Better than the Ee-A screen that I thought was milky.
Motor speed is important and I am thinking of a way using a submini mic and
a "Microchip" to regulate speed. (sharper with motor on)
Screens are rather cheap $35 so if one is building your own the Ee-A is brighter
but not as sharp.

I am going off my original post of companies that work on the primes........

EDIT: The website: jetsetmodels.info has a plenty of info on making them.
http://www.cinevate.com/website/index.php/cinevatevideouniversity/ has
great video on focusing them.

Are you saying to bypass a DOF converter entirely?

I still see 1/2" pickup cameras with converters being used.
Rented cameras with larger pickups are so impressive with their image without
one. Makes me dream of the image with one attached.

"Are you saying to bypass a DOF converter entirely?"

Yes.
There's some good example footage on DVInfo of the setup I'm talking about.
Reason I suspect people are still using a 35mm GG adaptor is that gets you closer to the kind of DOF of 35mm. You can get an incredibly shallow DOF out of the EX1, nose in focus, eyes out of focus. It looks very different to what you see on a 35mm print. Turning down / off Detail should help prevent this sharp transition from in to out of focus.

Bob.

I have been asked about the tubes.



They are the CHEAP ones on eb ay. You will need to order at least 2 sets
for your lens type. (Nikon, Canon, etc.) perhaps 3 or 4 total.

Set your camera on a flat surface, kitchen counter top. Place an object with lettering
in front of your camera. Zoom in/out and focus on the lettering. Measure the distance
from the object to the front threads of your lens.
60mm is roughly a set. 3 distance rings (approx. 7mm, 19mm, 29mm).
This is not the actual length of the set because you will need step up/down rings
this is roughly a gauge so you don't under order the tubes you need!

The set has a male and female ring for your lens. The rest are varying lengths
of threaded rings numbered 1, 2, and 3.

For macro shooting, extension tubes are great, but you already have greatly reduced DOF from the large format.

There are certainly some cases where macro tubes could be used to create a cool organic title sequence, but for run-of-the-mill it is a lot easier to do the DOF in your computer. Especially in After Effects where you can use specific lens blurs and even bokeh.