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C mount & standard glass on a budget

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ROCKMORE

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I have a number of lenses from other cameras. Some are c-mount and others are standard from an Arri 2c.
I'm on a budget so this is where I have to start.
All the glass is in perfect condition. I know the resolution is much lower that Zeiss Pl primes but I don't have a extra 20 grand at the moment. Can anybody give me a clue how the images will look.
This is what I have to start with.

Switar 10mm (c-mount)
Zeiss Distagon 16mm (35 Arri Standard Mount)
Angenieux 12mm to 120 zoom (c-mount)
Zeiss Sonnar 135mm (35 Arri Standard Mount)

Plus a full set of Zuiko lenses with a c-mount adapter
 
Lenses

Lenses

There are many factors that go into how an image will look shot with a Bayer sensor camera with an OLPF.

Although 16mm C mount lenses of 40+ years ago may not have come up to lenses for 35mm or VistaVision in regard to resolution per frame height, they probably approach SD resolution or better maybe in some cases.

16mm film never quite got to SD resolution in the same sence as looking at 35mm on a SD TV, you can see for the most part when film was 16mm vs. 35mm even though you are looking at a SD TV set.

But 16mm lenses were maybe better than 16mm film, so using them on a 3K sensor camera you might get up to the needed 1280x720 resolution for 35mm filmout if you use the 16mm lenses at prime stop, about f/4.5 to f/6.3. (Pixel count and visual resolution are not the same thing, you figure 3K*0.707=2.1K just from the digital image the add losses from the OLPF and lens.)

Since there is a sharpen option in the de-Bayer software that works like an un-sharp mask, and so can reduce some of the fuzz that lenses have, making the images look sharper if with some extra noise. If you use bad lenses wide open and over sharpen then you get the "video look" like a camcorder, which can have soft lenses and too much sharpen.

Maybe you should try the lenses you have and look at the results at various stops and sharpen settings, if you sit far enough from your monitor maybe you will be happy enough with what you get from some of them.

There are good modern machine vision lenses that do not cost too much new you can look into after you get your Scarlet to add to your focal length choices.

I just purchased a 75mm f/1.3 lens that is just awful wide open, but could be used at maybe f/5.6, so the stop you pick can impact how crisp the images look. You do not want to use stops smaller than about f/8 unless the lens is very bad since the resolution goes down for many good lenses as you go past f/8 to f/22.

The very best lenses may peak their resolution and high frequency contrast (MTF) at f/2.8, but few if any are above SD resolution wide open or at stops wider than f/2.0.

The 2/3" sensor is 11mm image circle about, so that is within what most regular 16mm lenses cover. Be sure video lenses are C mount and not CS mount since they are not the same, and that they cover 2/3" sensor or more. (the sensor is not 2/3" that is just its designation, at 16:9 it is somewhat taller than Super8 camera frame width).
 
Lens recommendations

Lens recommendations

Thanks Dan,

Do you have any specific lenses to look for on a budget?
I assume the lenses offered by Red will be designed to produce good results and at a reasonable price.
 
I had the Bolex bible sitting on the table next to me when I read this thread ( not sure why now? ). In it, it says that the 10mm Switar doesn't cover the Super 16mm frame and could result in some visible vignetting, so could this have the same affect on the Scarlet? Maybe someone with a bit more knowledge than me could answer that..

Adrian
 
Dan Hudgins said:
16mm film never quite got to SD resolution in the same sence as looking at 35mm on a SD TV, you can see for the most part when film was 16mm vs. 35mm even though you are looking at a SD TV set.
Click to expand...
That's like saying you can tell the difference between a Sony F900 and a RED by watching in HD (which you can) and then claiming the F900 isn't HD resolution.

I've scanned 16mm to 2k and blown it up to 35mm for projection with perfectly good results.
 
10mm Switar

10mm Switar

Adrian Frearson said:
I had the Bolex bible sitting on the table next to me when I read this thread ( not sure why now? ). In it, it says that the 10mm Switar doesn't cover the Super 16mm frame and could result in some visible vignetting, so could this have the same affect on the Scarlet? Maybe someone with a bit more knowledge than me could answer that..

Adrian
Click to expand...

The 10mm Switar covers 16mm which is 10.26mm X 7.49mm. The Red 2/3 sensor is 10.1mm X 5.35mm which will fit inside the 16mm gate so it will cover without vignetting. The Super 16mm gate is 12.52mm X 7.41mm and is too large for standard 16mm lenses to cover. In this case the 10mm Switar will vignette.
 
Liam Hall said:
That's like saying you can tell the difference between a Sony F900 and a RED by watching in HD (which you can) and then claiming the F900 isn't HD resolution.

I've scanned 16mm to 2k and blown it up to 35mm for projection with perfectly good results.
Click to expand...

How does this apply to my question about the quality of 16mm Switar lenses and older Zeiss Distagon, Angenieux, etc.
The final output for this project is TV and not projection. I would think the images would look pretty good until I can add on some higher end glass later.
Again, any suggestions for acceptable used glass to look for on a budget while waiting for the 2/3 Scarlet to arrive?
 
ROCKMORE said:
How does this apply to my question about the quality of 16mm Switar lenses and older Zeiss Distagon, Angenieux, etc.
The final output for this project is TV and not projection. I would think the images would look pretty good until I can add on some higher end glass later.
Again, any suggestions for acceptable used glass to look for on a budget while waiting for the 2/3 Scarlet to arrive?
Click to expand...

I'm saying 16mm film was a good format, capable of much more than SD.

Your old 16mm lenses should work well assuming you can mount them. I often use 30-year-old Nikon Ai lenses on my D300 because I like the look. Only proper testing will tell you if you like the look of your lenses.

I'd hold off buying lenses for these new cams until we know more about them - still no working prototype!
 
c mount 16mm lenses will cover 2/3" Scarlet just fine. I am in the same situation, having a few c mount lenses from 16mm cameras. To fully resolve 2/3" Scarlet needs lenses with around 120 line pairs/mm resolution.
Many premium quality 16mm lenses, like the Switars, are capable of this. There may be some slight shadowing or vignetting on a digital sensor near the edges of the frame due to film lenses not being of optimum telecentric design, but I think they will do just fine until we can afford something better. The Switar 10mm may show some chroma abberation if it is the RX version. The 12-120 should look very much like it did on film. I can't wait to run some tests with a Scarlet and the old glass myself. If the performance is decent, it would make a great upgrade camera for film schools as they could use their existing 16mm lens inventories.
I have bought a few more older 16mm lenses from Ebay to play with too, including a selection of zooms from Angenieux and Schneider. The total price for all of these would not buy a premium used S16 zoom like a Canon 8-64, so I don't think I will suffer much loss on them, they are fortunately all in very clean good condition. I want to do a test database on a selection of the most common types available as a reference for Scarleteers.
Personally I think the quality of some of these old lense will surprise people. They should be a viable low cost alternative for students and hobbyists.
Arri mount lenses will work with PL mount adapters too.
 
Sample 16mm film

Sample 16mm film

Liam Hall said:
I'm saying 16mm film was a good format, capable of much more than SD.
Click to expand...

Can you send me a sample of your 16mm film to scan so I can see what you are talking about? I only need maybe six inch lengths, maybe from an outtake. They may get scratched being put in the gate so nothing important or that you will need back.

I can post the results of the scan so we can all see, maybe?

Please attach a note with the lens used, f/ stop used, and film type number on each sample clip so I can note that when the scans are examined.

Remember that 2/3" sensor at 16:9 is smaller in height than regular 16mm, so to get a real evaluation of how the 16mm lenses will look on Scarlet the regular 16mm image must be cropped down to the sensor dimensions.

Most 16mm color film stocks can resolve about 50lp/mm well. With the 2/3" 16:9 frame being about 5mm high that results in about 500 video lines, so film's softness resolves less than 625 video lines at high MTF, at lower MTF you do get something but little in the over or under exposed parts of the frame. Super16 was developed to over come the below SD resolution of 16:9 on regular 16mm, but the Scarlet sensor is not Super16mm size, it is smaller than regular 16mm size, so the lens resolution is what you get in that area, not the full regular 16mm frame, but a crop of that area's height. It is true that newer ECN stocks resolve better than older ones, but older lenses were desigined for the limits of older film stocks.
 
Specific

Specific

ROCKMORE said:
Do you have any specific lenses to look for on a budget?
Click to expand...

I am still looking into what will be good to pick up. Newer lenses seem to have good coating and crisper results. The Fujinon 5 Megapixel 2/3" lenses may be something to look at they cost less than about $500 it seems, but do not have focus scales or f/ click stops so you would need to focus and expose on the camera's monitor. You can ask for sample lenses for testing. There is the issue of the thickness of the OLPF and sensor cover glass and their impact on the lens correction at large f/ stops, so the best way to check that is with a sample and test charts.

Like I said, what f/ stop you use the lens at has an impact on the end result, there are some very soft high speed C mount lenses that when viewed on a SD C mount video camera look soft wide open.

What "resolution" means to one person may vary from what it means to another, but if you can see a change in the resolution on a SD monitor as you adjust the iris then it would show that the lens has a circle of confusion larger than one SD pixel at some stops.

To get the resolution limit of a 3K camera is very hard. If you feel that having the circle of confusion spread over an area of 9 pixels or more is better than SD resolution then maybe you will be happy, but you are not resolving the limit of the 3K sensor in any way shape or form at high MTF.
 
Keep an eye on this thread and related ones.
A lot of C mount, old Bolex lenses are used and tested on a camera with a sensor twice larger than 2/3" (22mm diagonal).
Some perform beyond expectations.
 
There have been some pretty remarkable advances in lens coatings and optical design in the last 15 years or so. Newer lenses will have better color saturation and contrast for sure. It is interesting that some cinematographers still shoot with some of the older premium lenses because they like the look of them, even if they are not as sharp or saturated.
I used to shoot a fair amount of 16mm for SD video finish, and I can tell you for sure that a Bolex with a Switar zoom and Kodak 5247 negative stock in the early 80's produced much better images all around, when transferred on a flying spot telecine scanner, than all but the most expensive top line TV cameras.
 
Large sensor vs. Sarlet

Large sensor vs. Sarlet

Valeriu Campan said:
Keep an eye on this thread and related ones.
A lot of C mount, old Bolex lenses are used and tested on a camera with a sensor twice larger than 2/3" (22mm diagonal).
Some perform beyond expectations.
Click to expand...

If you use a large sensor you get more video lines per image height, of cource a lens will look better on a larger sensor up to the limit of its coverage since the circle of confusion is smaller in proportion to the image height.

The issue is what a lens will do on a 3K 2/3" 16:9 sensor. The crop in image height for the Scarlet sensor is like doing an optical zoom on a regular 16mm frame height.

Using Bolex RX lenses is another issue, the are not desigined to focus in air wide open. You can clean up soft results with an un-sharp mask, but GIGO, you get better results with out having to use signal processing.
 
IR focus

IR focus

David Rasberry said:
There have been some pretty remarkable advances in lens coatings and optical design in the last 15 years or so.
Click to expand...

One thing to think about is some newer machine vision lenses are corrected for IR focus and older cine lenses are not.

Even though you may use an IR cut filter, the lens still transmits some IR and if that is out of focus on film it does not matter much, but on a sensor you can get a halo or soft edges from IR leakage.

UV focus is also an issue with sensors, some older zoom lenses seem to not focus UV well and give a blue halo also.

So using lenses desigined for broadband UV to IR focus can give better results on a sensor that would not be visable on film...
 
The RX series Switars are not the best choice as they are chroma corrected for a reflex prism. The non RX Switars are good though. There are a lot of older Arri 16mm lenses, like the Schneiders, Cookes, and Zeiss's that should do pretty well too.
With all these new cameras coming out, I am hoping that there will be some new moderately priced lenses to match with decent mechanics and performance.

Rockmore, your Zuikos should do quite well too. Olympus has a reputation for making very good glass.
 
Rockmore,
I envy you for your Olympus set.
They have an amazing range, all at f2: 21, 24, 28, 35, 40, 50, 55, 85, 90, 100, 150, 180, 250mm and 350 f2.8.
Hard to find though and fetching good money.

PS
Shooting a feature with RED1 recently, the most 'needed' lens we didn't have for CU was the 75mm.
 
Collecting old lenses is quite nice and some would give amazing results in the right situation.

One issue is the consistency of the look; they vary so much and be aware changing lenses for a scene especially for a narrative piece.

A lot can be 'fixed' in post, but not always the best solution.
 
consistency

consistency

Valeriu Campan said:
One issue is the consistency of the look; they vary so much and be aware changing lenses for a scene especially for a narrative piece.
Click to expand...

I would agree about using lenses of different brands in the same project, the coatings and design can make for some shifts in the way the lens responds to out of focus parts of the frame, and the color of the lens flare.

I used a Bolex Switar 25mm f/1.4 in my first film recorder setup, I was using the highest resolution movie film kodak made, 7360 direct positive. The CRT was running at 720x348, about SD resolution. At f/1.4 the lens did not cleanly resolve the scan lines, so I ended up increasing the exposure to about 90 seconds so I could stop down to f/5.6. At f/5.6 the lens did better but most lenses do well at f/5.6 the true test of a high resolution lens is how well it does wide open.

In some cases you might expect C mount lenses to only resolve 380 video lines on the scarlet sensor height at 95% MTF wide open. To get the full sensor resolution you need 1600 video lines resolution (in about 5mm), so you are only getting about 1/4 what you are paying for in the sensor "brain" part of the camera... 800/5 = about 160lp/mm to get above 1080p resolution at high MTF.
 
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