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12mm Ultra Prime issues with RED ONE 4K?

Curran Giddens

Curran Giddens

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Anyone know of any issues like portholing or distortion with the 12mm Ultra Prime on RED ONE shooting 4K?

The person picking up the lens won't be able to test. I would image any issues would be due to the lens itself. They would be the same with both film and RED.
 
we used a 10mm UP in december and experienced no problems.

regards,
martin
 
Shoot 'em up

Shoot 'em up

The 12mm UP on the RedOne at 4K should make spine tinglingly great images with virtually no perceptible distortion and no portholing. Its a fabulous lens that really shows off the strengths of 4K acquisition.
 
Curran Giddens said:
Anyone know of any issues like portholing or distortion with the 12mm Ultra Prime on RED ONE shooting 4K?

The person picking up the lens won't be able to test. I would image any issues would be due to the lens itself. They would be the same with both film and RED.
Click to expand...

I shot the 10mm. No problems.
 
One more question about the 12mm UP.

What about using an MB20 with 5.65x5.65 filters? Will there be vignetting?

Do we need to go with a 6x6 mattebox instead?
 
Hey Curran

Most lens rentals wider then 14mm come with their own clip on style MB that come in the case with the lens and hold 6x6 filters. These MB's are usually specific for the wide lens they come with.

I am 99% sure the 12mm UP will not work with an MB20 and 90% sure it will not work with most typical 6x6 MB's.

Ask the rental company you are getting the 12 from as they should be able to help.

cheers
Daren
 
I own a UP 12mm and use it all the time on the Red at 4K....no issues.

Regarding mattebox/filters...we include a LMB-4A with our lens and 6X6 filters...no problems.
 
OLPF filter

OLPF filter

Hi everybody,

Interesting to hear you all have no issues with lenses wider than 14mm.

I tried to use a 10mm UP on RED @ 4K resolution

These were the issues I had:
After receiving the lens (subrental) I mounted lens into lens projector and found it in perfect back focus.

The put lens into RED and back focus was a foot off -

Repeated procedure and tested mount with other lenses - those showed up in projector and RED with consistent results. Then checked lens in projector again and found it in perfect back focus.

Put 10mm back into RED and lens wouldn't show up on scale.
Then added about 0.025mm and got a good center of frame consistent with scale of lens. BUT:
Lens showed a significant fall off in resolution to both sides of frame.
After a couple of calls to camera technicians in other rental houses that have RED I was told by a source from Munich they had experienced similar effect - we agreed that OLPF filter could have something to do with this.

The customer ended up using the 10mm only in 3K and 2K (higher frame rates) and then switched to our 14mm as widest lens.

Any comments or similar experiences? Pretty sure after double checking that I didn't just mess up with lens projector.

Best
 
Volker Ehlers said:
Put 10mm back into RED and lens wouldn't show up on scale.
Then added about 0.025mm and got a good center of frame consistent with scale of lens. BUT:
Lens showed a significant fall off in resolution to both sides of frame.
After a couple of calls to camera technicians in other rental houses that have RED I was told by a source from Munich they had experienced similar effect - we agreed that OLPF filter could have something to do with this...

...Any comments or similar experiences? Pretty sure after double checking that I didn't just mess up with lens projector.

Best
Click to expand...

When testing the SI-2k about a year ago I felt the OLPF (quite thick in the SI-2k) was an issue... Any Distagon 12mm or wider was way out. All lenses where checked properly and we went through 4 sets. Ultra16s where a bit better. I am sure it is possible you are seeing this problem with the 10mm. It has been my (very lay) understanding that focus is not straight and completely parallel to the image plane but curved. Could this not explain your fall of in resolution (more a fall of in focus).

The received wisdom with the SI-2k is to use per lens (differently shimmed) PL mounts. This is less possible with the Red so you would have to change at the Lens..

I have a chart somewhere which details the how telecentric different UP are.. I dig out and have a look at the UP 10mm. Perhaps it is less telecentric than the 12 and 14mm.

regards

Michael L

PS this thread had some talk about OLPF problems..


Michael Lindsay said:
I tested a range of lenses on a SI-2k the other day. The OLPF causes problems. When using a Zoom that is very retrofocal (to the point that the light out the back is very telecentric) you get very good results.

If using a wide prime lens I saw CA and sizable backfocus problems. The back focus pproblems are solvable on the SI-2k by using per lens PL mounts. The CA?

I believe the above may to a lesser extent be applicable to Red.

reagrds

Michael
Click to expand...
 
to add to the general consensus about the 12mm:

The 12mm for me is wonderful... We rarely use it but love it when we do get it out. Finner and Greg are correct the LMB4 is the common way to go with a MB. With a special made filter tray PV size filters will work. The MB28 will just about work I believe.

I wish somebody would offer a modification for the 12mm to reduce the the front to something that would give other MB options. I personally don't like the LMB4 and would rather other options.

regards

Michael L
 
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