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Old December 20th, 2005, 11:43 AM   #1
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Feature film shooting with jvc and mini 35 adaptor/congrats + questions 4 charles

Hi guys
Thanks to charles and team for the test info. on the jvc cam and mini 35 adaptor from P+S Technik. I am a co-producer/writer/director of an independent film called Spoon that is in pre-production at the moment. We are based in cape town, south africa. We are planning to use the JVC cam and mini 35 lenses to shoot the film and have purchased two of each unit for testing. We are working with a company called cineform and capturing direct to disk using the new cineform codec which is amazing. We are presently shooting tests and found Charles + teams' test footage and results most helpful.

Here are a couple of questions for Charles+team (and anybody else who has any ideas) interwoven with some info from our tests so far:
1. FOCUS- in your opinion, does the "softness" that one gets with the mini-35 give the same kind of softness drop as one could expect with 35mm film or is it more? Obviously we want a softer film look but we seem to be too soft on our tests. We have been struggling to get sharp focus through the mini 35 lens. On our first tests our ground glass focus went out very slightly. Its very very sensitive and seems to be something that one needs to check regularly. We've been doing some technical tests but your stuff seems to be sharper than anything we've gotten to date. We did a bunch of exterior night stuff with rain etc. which I'm going to try and post up. We just started shooting the day stuff.
2. We have noticed that the focus assist doesn't seem to work if there is not enough light. Did you guys find that as well?
3. What setting was your sharpness on when you guys shot the tests?
4. Your gamma was on +3 for the night shots – where there any other settings you used on your day shots that might help us (master blacks etc.)
5. Which lens did you guys use for the shot called AR_walking hands?
6. What stop loss do you think you were getting? The mini 35 guys say that we should loose about 1.5 stops - we have done several technical tests which confirm that we are getting something a lot closer to just over a 3 stop loss. ie. F4 on the fujinon = T1.3 on a carl zeiss 25mm

We now have some interesting results so far from the day test shots that literally just came in:
a. as one would imagine, we found that it helped the focus hugely to shoot with detail on - we had originally wanted to avoid this as we understand its a digital process so we wanted to shoot the "cleanist" image possible and then rather try and sharpen in post. (we own a big post facility) We want to try and avoid any digital mess that might appear when we blow the footage up to a 35m print. However so far it seems that it's better to use the camera's detail settings. Do you guys have any thoughts on the detail setting issue?
b. We found that when shooting daytime ext. city shots, we got the most detailed and clean image by stopping down on the relay lens and shooting wide open on the prime lens. ie: our prime lens was wide open and we used the relay lens to get correct exposure. We had originally heard that it should be the other way around so this was a surprise.

We have a lot of night ext. and int. shots in the film so our biggest concern is likely to be the stop that we are loosing. We need serious light power. Basically on all our interiors and night exteriors we are having to shoot with relay and prime lens wide open. The fact that it appears that we get a cleaner image if we can stop down on the relay lens is frustrating and we're a bit in the dark at the moment if you pardon the expression.

you can keep updated with our progress on the capture side (we're using brand new codec technology in partnership with cineform) at http://indiefilmlive.blogspot.com/

ABOUT OUR PROJECT
Spoon is a supernatural thriller with a lot of visual effects. My partner Simon Hansen and I aim to help pioneer a new genre of film that we're calling "commercial independent". Basically films that have large scale production values produced on indie budgets. To see the kind of stuff we've done with no money in the past visit www.thesas.com and download the shortfilms on the viral page. One features a space shuttle landing in cape town and the other a digital artist training boot camp. We also recently co-produced a short film directed by our friend Neill Blomkamp. Its called Alive in Jo'burg and features aliens living in a south african township. www.ratel.ca
Our vfx company is www.atomic-vfx.com
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Old December 20th, 2005, 06:57 PM   #2
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Hi Sharlto, howzit?! Glad you found the footage useful.

1). "Sharpness" is a complicated term when used to compare film and video. I think that the slight softness that the Mini35 creates is part of what makes it look more pleasing to the eye; I find straight HD in general to sometimes be overally sharp in appearance (which is why I'm not a resolution-hound, only gravitating towards the most number of lines or resolution charts). Many have noted that the shot in our tests of the female model in front of the flowerbed is noticeably softer with the Mini35 than the straight-up version, but I can't say for sure since this was the first images we shot that day that we had dialed in the back focus (or even the front focus) perfectly.

2). Focus assist issue--Hadn't noticed that. I can well imagine that if there isn't enough contrast in the image it would have problems. Our night photography was fairly contrasty with highlights throughout.

3, 4, 5) Here are the notes that I had on the shots (I don't have anything on the detail, but I believe it was at unity (0):

All clips were 720/24p, 1/48 shutter, motion smoothing OFF unless noted. 0 db gain. All Mini35 clips shot with Cooke S4 lenses at T2, Mini35 set at speed 6.

Static test with Amy and flowerbed:
Mini35, 50mm
WB set at location
Cinema Mode ON
Color gain: 6
White clip: 100
Knee: 90%

Rack through greenery:
Mini35, 100mm,
Cinema Mode OFF
color matrix standard
cinema gamma : 3
color gain: 6

Greenery with Amy and Robert walking
Same settings as above

Amy and Robert walking, ends on holding hands
Same settings as above

Amy closeup
Mini35, 100mm
Settings otherwise same

Rob closeup
Same settings as above

Night exterior: Nicolette walks right to left
Mini35, 27mm
Color matrix: Cinema
Gamma: standard
Gamma level: 3
Color gain: 3

6) Stop loss issue: I would say that this probably has more to do with the markings on the Fujinon than anything else--it has been surmised that they are probably not all that accurate. Bear in mind that you are comparing T stops on the Zeiss (actual measured transmission) vs f-stops on the Fujinon (theoretical transmission). I personally feel that the Mini sucks up between 1.5 and 2 stops of light.

Regarding detail, I prefer not boost it in the camera as I think it adds a video "look" to the results.

Regarding which lens to adjust exposure, it is standard practice to set the cine lens at the desired aperture for depth of field purposes and adjust exposure via the relay. You should not see an optical difference with the relay wide open vs stopped down. When you say that the image was cleaner when the relay was stopped down, in what way? If the backfocus of the Mini35 is not properly adjusted, you will see a focus shift as you stop down the relay (it will improve), so remember that backfocus should be adjusted with the relay wide open and the cine lens stopped down to make the groundglass texture more apparent (Mini35 motor off, of course).

Good luck with your ventures!
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Old December 20th, 2005, 07:20 PM   #3
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My hats off to you Charles. Only a select few BOLD Cinematographers are confident enough DP's to give up their camera settings for the goodness of indie-kind. You're a scholar & a gentleman.

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Old December 20th, 2005, 07:24 PM   #4
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Thanks for the kudos Shannon, but honestly I believe that lighting and composition are far more important factors for creating one's individual look than camera settings--I prefer to do more of the manipulation in post-production anyway, when you can judge the image more accurately and aren't under-the-gun.
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Old December 20th, 2005, 07:30 PM   #5
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Here here.

Hi Charles. Just another thank you. I am also involved in Spoon and we all greatly appreciate your assistance.

Simon
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Old December 21st, 2005, 05:50 PM   #6
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Quote:
Originally Posted by Charles Papert
Regarding which lens to adjust exposure, it is standard practice to set the cine lens at the desired aperture for depth of field purposes and adjust exposure via the relay. You should not see an optical difference with the relay wide open vs stopped down. When you say that the image was cleaner when the relay was stopped down, in what way? If the backfocus of the Mini35 is not properly adjusted, you will see a focus shift as you stop down the relay (it will improve), so remember that backfocus should be adjusted with the relay wide open and the cine lens stopped down to make the groundglass texture more apparent (Mini35 motor off, of course).
Hmm- no problems with diffraction then from the relay lens being stopped down too far? Not just a question for Charles as I realise he only had this rig for a short time to play with.

I think we discussed elsewhere that anything stopped down further than F8 on the stock lens caused diffraction issues for all those pixels they crammed in on the sensor. Maybe it's not an issue on the relay lens?
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Old December 21st, 2005, 07:28 PM   #7
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I'm going to hazard a guess on this, but I believe that because the light rays going through the relay are more parallel (due to the nature of the projected image on the ground glass) than one would encounter in a normal lens situation, diffraction and refraction are not as much of an issue. Probably there is a point in which stopping down the relay could be a problem. I've always tried to keep it around the middle position and use ND accordingly (on the camera or on the cine lens) to be safe.
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Old December 23rd, 2005, 03:26 AM   #8
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relay lens vs prime lens

thanks for all your feedback charles. thats my co-producer/director simon posting above. We have been doing extensive tests and i'm still trying to get permission to post up the files with results but we have discovered the following:
1. we are definatley getting a difference between having the relay lens wide open and stopping down on it. when the relay lens is wide open, we can see the texture of the groundglass a lot more clearly and this messes up the image and results in a loss of detail. (when its stopped down, we find that the "spinning" groundglass grain gives a nice filmic look) With the relay wide open, the image also goes slightly yellow- overall it somewhat resembles the kind of thing one might see on a bad lens. my dop thought that perhaps this was because of the relatively poor quality of the mini 35 relay lens
2. we seemed to get a slightly more focused image as we stopped down on the relay lens, even when we set the backfocus with the relay wide open as you suggested.
3. john we haven't noticed any problems stopping down on the relay lens
4. at this point it looks like shooting with detail on normal is getting the best results.

It seems that the results are good as long as the relay lens is not wide open. This is a problem for us because we have a lot of night and low light shoots, but we're still testing and trying to see if we can make it work.

Charles a quick question - we're still waiting for our HD res monitor. I'm thinking we can't trust the camera's monitor/computer monitors for things like focus/detail. When you guys shot did you find yourselves relying heavily on the HD monitor as you were working?
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Old December 23rd, 2005, 12:52 PM   #9
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Sharlto, welcome to the world of relay lenses, or in my case the HD dvx100a with it's built in "relay" lens. They suck, that is my feeling after playing with every sort of 35 adapter I could get my hands on, even building one from scratch.

It's very true that the relay lens will make your images softer when it's open, the reason? as far as I can tell a 1/3rd inch ccd is so small in size that your almost at the OPTICAL limit of glass to get above a 720x480 3ccd image, with the dvx100a and it's pixel offsetting we are getting 1540x984 HD frames from the camera, you can see shots here:www.reel-stream.com they look great, however when you open the dvx lens all the way IN HD ONLY it's lens goes soft, not so with SD, that looks great...not enough resolution to show the softness.

WIth your camera setup, your getting 1280x720 3ccd images from a 1/3rd inch chip! Far more resolution is needed from your glass then the dvx pixel for pixel. I'm sure your pixel sizes are smaller(they must be to fit them on a 1/3rd inch ccd) and this creates the need for cleaner glass. If you think about it, the 35mm glass on the front of a ground glass system does not need to resolve as much because it's image area is 24mm x 36mm approx. so your "limit" is the relay, or in my case the dvx lens..then ontop of that your dealing with the issues of focusing 2 lens systems, A feature I would hate to deal with on a "real" production outside studio test images. I have a feeling that your dealing on a level that many people don't have a need for, feature work from a relay system, I have been doing the same thing. I think the ONLY way to see what you think is a 35mm test print, I have not done this yet as we decided to shoot on the VariCam instead of the relay system, I'm not that blown away by the varicam but, it does have one lens system that is SHARP!!!

here is a SD spot we shot with the relay and the 4:4:4 from the dvx:
http://www.reel-stream.com/gallery_i...1&image_id=174

and a test comp using lightwave:http://www.reel-stream.com/gallery_i...1&image_id=173
building and ground are the plate

and yet a 2nd 30sec spot, not using relay system, just the uncompressed footage of the kid and his leg breaking the surface
http://www.reel-stream.com/gallery_i...1&image_id=183

-Obin
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Old December 23rd, 2005, 01:26 PM   #10
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Obin, so what are you saying?

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Old December 23rd, 2005, 01:28 PM   #11
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IMHO, the relay system is not up to spec for feature work, anything above an HDTV set I don't think they work well for, maybe the pro35 has better glass and would work well. I have never used the pro35.

does this answer your question?
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Old December 23rd, 2005, 01:41 PM   #12
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Sadly, yes.

Maybe P&S will make some upgrades to their stuff to handle HD for the Mini35.

I wonder if this problem persists with using the Mini35 & the Sony Z1U. and I wonder if Nate Weaver experienced any of this when making his Music Video.

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Old December 23rd, 2005, 01:59 PM   #13
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Thing is, they KICK MAJOR BUTT for anything BUT full on bigscreen, so I think 99% of projects are great with the 35mm units..I can't shoot anything without one now days, looks like cheap video without it! LOL.. dunno if you have seen it but here is a spot I just shot and cut, using nothing more then dv tape!!!

www.dv3productions.com/work/teletexas.wmv
the girl has no adapter

on a standard TV that spot looks great

make sure you use IE to view it, FireFox has a lameass plugin that resizes work to full screen, even if it's native 320x240!

here is the first test output from the dvx100a HD with the new 4:4:4 hardware and the micro35 with a nikon 105mm lens...
www.cineform.com/video/ama_cineform2.avi
a bit short for internet downloading, but I think you can get the idea of what this could look like, used one hard light for this "test" shot..
gota get the cineform codec to view this file at www.cineform.com

guys how does this cineform file compare to your 1280x720 mini35 captures?
BTW this has been into AE so the dark edges are a mask, FYI ;)
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Old December 28th, 2005, 12:15 PM   #14
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Hello Sharlto,

You say:

“We found that when shooting daytime ext. city shots, we got the most detailed and clean image by stopping down on the relay lens and shooting wide open on the prime lens. ie: our prime lens was wide open and we used the relay lens to get correct exposure. We had originally heard that it should be the other way around so this was a surprise.”

In theory if the relay is set optimally, there should not be a significant change of sharpness when the iris on the relay is closed.
I did setup a JVC GY HD100 on the Mini35 and focused the relay wide open using a chart. Then I closed the relay iris to see if I get a change in sharpness. At first, on the monitor I had available, (not a HD one) I did see a small improvement in sharpness and contrast between position 1 and 4 on the relay’s iris. But the monitor was displaying two images with very different intensity and I found that the higher intensity did not render as good an image. (I wonder if you were under similar conditions)
To avoid this problem I adjusted the light on my chart as well as the aperture of the relay to keep the display even in intensity and under those conditions I could not see any change in sharpness of the image.
I suspect you are not able to see the best position of you relay when it is wide open.

Let me know if you are still testing the system.

Best regards,
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Old December 29th, 2005, 04:21 PM   #15
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Sharlto and Simon,

I located here in Canada and have been running a mini35 unit since late 2003. I originally ran it with a PAL version of the XL1se (I used 25fps/50i to achieve 24p in post for NTSC) and since last year have been using the XL2 upon it's release. Now that the Canon HD XLH1 is out I'm kicking myself but oh well.... ;)

My experience with the mini35 unfortunately is limited to 16:9 SD (864x480) but of my 2 years experience using the mini35 I have noticed the best images came from my system with a slightly stopped lens (f2 to f4) and a slightly stopped relay lens. Scientifically I have no idea why although some of the posts here seem to indicate some reasons. When I shoot I also periodically check the back focus once the f-stop of the lens is set so you might want to try this as well until you find the sharpest point of focus.

Another tip, I'm not sure about other users of the mini35 but I have noticed vignetting if you stop down the relay lens past say "5". So as a rule of thumb I never go past this when shooting outdoors and if necessary throw on a Neutral Density filter.

Your problem however seems to be the opposite of all of this and having shot in night interiors and exteriors all I can say is shooting wide open (f1.2 or f2) on a 35mm lens poses some extremely challenging focus issues. For me mainly finding focus but also pulling focus if necessary for the shot. When directors want to dolly in or out under low light I cringe since usually I pull my own focus, an experienced focus puller would obviously help the situation but my point anyway is that you will get a wider depth of field with a lens that is stopped down to f3.5 or f4 which could make for some easier focusing but of course require more light. :(

In these night interior shots http://www.starcentral.ca/acorns.htm, with the lighting used on set it seemed as though the SUN was there with us - but through the mini35/XL2 proper exposure was obtained. In fact slight under exposure.

It might not make a lot of sense at first, but I've often suggested on some productions not to use the mini35 adapter for low light shots. Often depth can be achieved through good lighting and placement so perhaps consider that as an alternative option.

Lastly I've seen much of the work from you and Simon on the site www.thesas.com and can't wait to start seeing more from your project "Spoons" and the use of the mini35 and JVC on it. I also watched "Alive in Jo'burg" and think it's absolutely brillant! Would you mind sharing what 3D modelling programs and/or other software packages are used for your work(s)?

Cheers and best of luck in the New Year on all your projects!

Dennis
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