P+S Technik Mini 35 Adaptor - What do you want to know? - Page 4 at DVinfo.net

Go Back   DV Info Net > Special Interest Areas > Alternative Imaging Methods

Alternative Imaging Methods
DV Info Net is the birthplace of all 35mm adapters.


Reply
 
Thread Tools Search this Thread
Old August 17th, 2002, 12:23 PM   #46
Regular Crew
 
Join Date: Dec 2001
Location: Venice-Italy
Posts: 52
Well to the questions:
I used the fast Zeiss Prime set 1.3, the following lenses 18, 35,50 and 85, then I used the Cooke Zoom 20-100, I think 3.1. (It cost me a lot of money this test)

I always use the motor on "fast", otherwise I would always see the groundglass on the image.

I did two basic test,
- on set: it was the Western in the Universal Envirment, where I had nice textures of the "old" wood cowboy buildings, so I could quickly see where the spinnig is coming up. Ovviously there because of the limitations of the color viewfinder I saw the spinning only on higher F stop numbers.

- morally totaly depressed I retried a test with the technical people from the rentalhouse. I hoped that they could be more experienced then I was and would find that I did something wrong. (They didn't any experience before with the mini35, but where very competent)

We set up a simple situation: a yellow shippingbox on which was positioned a tube of big white paper. It was lit with 1 light (I think not more then 500W) from the side. The tube is good because you can see quickly where is overexposed also without the zebra-pattern

The frame we took was in a way that the tube crossed the center of the picture in a diagonal way.

The test was done with a fast Zeiss 50, 1.3, the controll was on a Sony Studiomonitor (I don't know the type, but it was one of those I would wish to have)

The XL1s is a PAL version, the GAIN I brought down to -3 (which reduces the visibility of spinning effect). Then we started to change and look what happens with the different balanceing between the lens openings and the relay openings. The spinning effect started around 2.8 1/ 3 and we could do nothing to improve the quality.

I retried the test also with the 18 mm lens, and I think it looked a little bit better, it seemed that the effect came here up only at 2.8 1/2 but to be honest I was too depressed to investigate further on.

Meanwhile I called P+S Technik (I bought the equipment in Italy) and they said that this should not happen, that maybe for some reason my groundglass is spinning too slowly so I'll send them the equipment for a check.

I really hope that it is the speed of the groundglass, because the images are otherwise really superb!!!!!!! So I beg everybody who DOESN'T have this problems to tell it, to encourage me, because I love this product.

Istvan
__________________
Istvan Toth
RED #1161
Istvan Toth is offline   Reply With Quote
Old August 17th, 2002, 12:41 PM   #47
Major Player
 
Join Date: Feb 2002
Location: Oakland, CA
Posts: 227
Hi Stevettt,

This is basically what I experienced. If P+S thinks that this shouldn't be happening then I have this fault as well. I keep my lenses at T1.4 anyway. That's just what I like to do. Yes, I'm screwed up that way. I do a lot of things that DP's don't normally do... ;)

Anyway, I'm going to talk to ZGC about some of this stuff. Please follow up on your end as well and we'll compare notes.
__________________
justin
www.monsterrocket.com
Filmmaker | Cinematographer
Justin Chin is offline   Reply With Quote
Old August 17th, 2002, 02:20 PM   #48
Regular Crew
 
Join Date: Dec 2001
Location: Venice-Italy
Posts: 52
Hi Justin,
well I'm very sorry to hear that you have the same experience, I hoped that only mine was like that.

I just looked in the American Cinemat. Manual what happens to the depth of field with a 85 mm lens at T1.4 on 6' distance: it would be sharp from 5'11" to 6'2", which means on a CU I would have to decide which eye to put sharp, left or right? Well Kurbrick did once a movie where every actor was not allowed to move, why shouldn't I learn to do it?

Anyway I'll post any news I'll have. Ah one very important thing: the people at P+S are very friendly and helpful, so if there are solutions, they will work on it to find it, I'm positive on that.
Istvan
__________________
Istvan Toth
RED #1161
Istvan Toth is offline   Reply With Quote
Old August 18th, 2002, 11:19 AM   #49
Regular Crew
 
Join Date: Aug 2002
Location: Paris, France
Posts: 126
Hmmm, I'm shooting a short film using the Mini 35. With the motor spinning on its highest setting, my DP and I don't see anymore grain.

We're using Cooke lenses: 14mm, 21mm & 40mm and an XL1 PAL with the frame rate at 25-interlaced fps.

The image is beautiful.
__________________
Strive not to be a success, but rather to be of value. - Albert Einstein

http://advaloreminternational.com
Victor Muh is offline   Reply With Quote
Old August 18th, 2002, 11:42 AM   #50
Regular Crew
 
Join Date: Dec 2001
Location: Venice-Italy
Posts: 52
Thanks Victor,
wouw so there is hope!!! I'm really glad to hear it!
Just two more questions:
- do you controll it on an external monitor?
- till what F-stop can you close down the 40mm lens till so start to see the spinning in the center of the frame?

Thanks indeed
Istvan
__________________
Istvan Toth
RED #1161
Istvan Toth is offline   Reply With Quote
Old August 18th, 2002, 01:42 PM   #51
Major Player
 
Join Date: Feb 2002
Location: Oakland, CA
Posts: 227
Victor:
Yes, what T Stop you're shooting at is very important. I mostly keep my lenses wide open at T1.4 and have no trouble at all.
__________________
justin
www.monsterrocket.com
Filmmaker | Cinematographer
Justin Chin is offline   Reply With Quote
Old August 18th, 2002, 02:18 PM   #52
Major Player
 
Join Date: Aug 2002
Location: Bethel, VT
Posts: 824
<<If you don't have the motor on and you pan or tilt, you'll see grain, with any focal length. I NEVER shut the motor off, because of the noticeable grain in the ground glass. It's like shooting through a dirty lens.
>>

Honestly, I don't see his in shots with proper exposure, and shorter focal lengths. In fact I just finished about 2 hours of footage testing the limits of the grain with pans and tilts at different exposures, motor: on, slow and fast using 35mm 1.4, 50mm 1.2, 85mm 1.4 and I was able to shoot with no motor in a number of configurations. YMMV
Jim Giberti is offline   Reply With Quote
Old August 18th, 2002, 02:35 PM   #53
Major Player
 
Join Date: Feb 2002
Location: Oakland, CA
Posts: 227
Wow, really. I haven't experienced that. If you can somehow write up your results with images or video that would be cool.

I have always seen the grain in any one of my lenses with the motor off when panning or tilting. Of course "proper exposure" is in question. Though I would say the shots I've seen it in are properly exposed. Slow and fast doesn't seem to make that much of a difference. When the motor is OFF is when I see the difference.

For the record I've shot more than 50 hours of footage with my mini 35 in the last month. 2 shorts and 1 feature still in production. Some of these things you can see in the field, it is when you look at them on the computer or projected is when you really start to see them. Though I've begun to notice it in the viewfinder. Probably because my eye is tuned to it.

I'll try and do some strict comparison tests, when I have some free time. That'll be in September.
__________________
justin
www.monsterrocket.com
Filmmaker | Cinematographer
Justin Chin is offline   Reply With Quote
Old August 18th, 2002, 04:11 PM   #54
Regular Crew
 
Join Date: Dec 2001
Location: Venice-Italy
Posts: 52
Jim,
excuse me but what do you mean here with proper exposed? Properly exposed for the limits of the device (keeping totaly open the frontal lens) or proparly exposed for what the image we want to photograph requests?

What I need is the flexibility to close down the iris till F5.6 without getting probelms with the ground-glass, rotating or not rotating. Right now I start to see the glass rotating in the center (!!!) around F 2.8 1/3.

Also can I not understand why panning or tilting could have any effects on seeing the grain. The grain is on the glass and the lenses of the mini35 are focused constantly on that plane. The only way I see could be to reduce the back-focus, something I definitly would not love to do.

Question, what model do you have? I have one of the later ones, which is revision 2002. I know they made some changes to the last years models, but I don't know what.
Istvan
__________________
Istvan Toth
RED #1161
Istvan Toth is offline   Reply With Quote
Old August 18th, 2002, 04:29 PM   #55
Major Player
 
Join Date: Feb 2002
Location: Oakland, CA
Posts: 227
Properly exposed images are somewhat subjective.

Seeing grain when panning or tilting is only an issue when the spinning glass is NOT on.

I have the 2002 model. They've made one change that I know of to this model. The motor switch is horizontal rather than vertical.
__________________
justin
www.monsterrocket.com
Filmmaker | Cinematographer
Justin Chin is offline   Reply With Quote
Old August 19th, 2002, 02:38 AM   #56
Regular Crew
 
Join Date: Aug 2002
Location: Paris, France
Posts: 126
We didn't have the luxury of a real external monitor. We used a 5-inch LCD monitor. This was a big mistake, because we forgot to turn on the spinning feature during an important shot. Using the 40mm lens stopped at 2, we can still see the grain, which looks like dust on the lens. It was a panning shot, so the grain is even more obvious. However, only myself and my DP noticed this when reviewing the rush. Most people didn't notice it.

Another reason to use a real monitor is that the exposure and color are difficult to judge with the viewfinder and an LCD monitor. The color in the viewfinder was very cold, almost blueish.

Basically from testing during pre-production (with a studio monitor), we decided to ALWAYS leave the Mini 35 spinning on high (the on/off switch at the back being horizontal). There's no reason not to. Even battery drain is minimal. Spinning the Mini 35 on high always produced the sharpest images.

We kept all the lenses stopped at 2. However, we played a lot with that "iris" that works like an adjustable ND filter.


<<<-- Originally posted by stevettt :
Just two more questions:
- do you controll it on an external monitor?
- till what F-stop can you close down the 40mm lens till so start to see the spinning in the center of the frame?
-->>>
__________________
Strive not to be a success, but rather to be of value. - Albert Einstein

http://advaloreminternational.com
Victor Muh is offline   Reply With Quote
Old August 19th, 2002, 03:29 PM   #57
Major Player
 
Join Date: Aug 2002
Location: Bethel, VT
Posts: 824
<<Jim,
excuse me but what do you mean here with proper exposed? Properly exposed for the limits of the device (keeping totaly open the frontal lens) or proparly exposed for what the image we want to photograph requests?>>

Well, I have to agree with Justin that "proper exposure is subjective". In general I mean that an under exposed image will begin to show grain much more noticeably than an over exposed one. Also, it appears that the "spinning glass" becomes more noticeable on a solid background (sky, grass, etc.) at longer focal lengths and above f/4


<<Also can I not understand why panning or tilting could have any effects on seeing the grain.>>

It's simple, in a static shot with a reasonably short depth of field, a slight bit of grain from the P&S can "dissapear" into the image. When you move the camera with a pan or tilt, the image changes but the grain pattern remains the same and because it doesn't move with the image it looks as though your looking through a dirty window as Justin commented.

<<Question, what model do you have? I have one of the later ones, which is revision 2002.>>

I believe I have the newest one in the US. THe one I orignally shot with had a different look, different motor switch and the iris wasn't as smooth. I know that the image coverage is enhanced (there was an issue with cine zooms needing to cover super 35 on older versions).
Jim Giberti is offline   Reply With Quote
Old August 19th, 2002, 03:40 PM   #58
Major Player
 
Join Date: Aug 2002
Location: Bethel, VT
Posts: 824
<<Meanwhile I called P+S Technik (I bought the equipment in Italy) and they said that this should not happen, that maybe for some reason my groundglass is spinning too slowly so I'll send them the equipment for a check.>>

Hey guys, one of the things I discussed recently with Mizell at ZGC was that the Germans designed the new motors with more bearing grease that some rental houses said had noticeably slowed down the motor. It was reccomended to them to open up the unit and put a drop of solvent on in order to dilute the grease and spin the glass faster. Obviously I would like to avoid this procedure. I'm a creative Jim...not a mechanic (in StarTrek Scottish).
Jim Giberti is offline   Reply With Quote
Old August 19th, 2002, 04:05 PM   #59
Major Player
 
Join Date: Aug 2002
Location: Bethel, VT
Posts: 824
<<This is basically what I experienced. If P+S thinks that this shouldn't be happening then I have this fault as well. I keep my lenses at T1.4 anyway. That's just what I like to do. Yes, I'm screwed up that way. I do a lot of things that DP's don't normally do... ;)>>

I do think this is probably the best rule of thumb Justin. Obviously there are some compromises that have to be made to get this quality of image with the XL and P&S vs 16mm or 35mm cost. I honestly tend to do the same in practice..that is keep everything open to 1.2/1.4 or a stop down. As you say, in this range with the motor on, you get a beautiful image and obviously a good deal of dimension with the limited dof. Where I see the real limitations so far (and I've got a long way to go with this setup) is with bigger shots, vistas etc, where there is a more uniform background.

One more thing, I just began expirementing with Heliopan circular polarizers for outdoor shots, and so far the results are nice. It gives a 2 stop or so effect while bringing more saturated color. I really need to test more and see how it compares to stopping at the relay iris in terms of grain.

One more, one more thing ;) Scott Billups considered the music video project that he shot with the P&S/XL1 setup to be the best miniDV footage he's ever seen, but also mentioned the need to use ND filters in order to get the dof of film. I'd like to talk to him and see if this was with the consideration of the grain issue. Without the time involved of a stop by stop lens by lens comparison, I would suggest that stopping down the prime lens with NDs may solve some of Istvan's issues with the need to shoot with more dof. I say this because my tests so far show that stopping the prime induces grain much more so than stopping down the relay iris with an open prime. I'll bet that ND's will give more flexibility still in terms of opening up dof without grain.
Jim Giberti is offline   Reply With Quote
Old August 19th, 2002, 04:08 PM   #60
Major Player
 
Join Date: Aug 2002
Location: Bethel, VT
Posts: 824
<<This is basically what I experienced. If P+S thinks that this shouldn't be happening then I have this fault as well. I keep <<Another reason to use a real monitor is that the exposure and color are difficult to judge with the viewfinder and an LCD monitor. The color in the viewfinder was very cold, almost blueish.>>

I hate to say it Victor but you've really got to spring for the B&W CRT viewfinder to round out this setup. You can see most grain in the VF while you're shooting and resolve the critical focusing inherent with the better lenses and dof. I use a 5" Nebtek on top just to give a color balance to the shot.
Jim Giberti is offline   Reply
Reply

DV Info Net refers all where-to-buy and where-to-rent questions exclusively to these trusted full line dealers and rental houses...

Professional Video
(800) 833-4801
Portland, OR

B&H Photo Video
(866) 521-7381
New York, NY

Z.G.C.
(973) 335-4460
Mountain Lakes, NJ

Abel Cine Tech
(888) 700-4416
N.Y. NY & L.A. CA

Precision Camera
(800) 677-1023
Austin, TX

DV Info Net also encourages you to support local businesses and buy from an authorized dealer in your neighborhood.
  You are here: DV Info Net > Special Interest Areas > Alternative Imaging Methods

Thread Tools Search this Thread
Search this Thread:

Advanced Search

 



Google
 

All times are GMT -6. The time now is 02:02 AM.


DV Info Net -- Real Names, Real People, Real Info!
1998-2017 The Digital Video Information Network