A poor man's Lens - worth it?

[sander kamp]

I bought a LOMO 37-140 T4.2 zoom for 350 US on Ebay. It might be comparable to the Lenar since they are both Russian, old and have similar zoom range. The LOMO is incredibly bad wide open on the long end. But as said, at T11 it is quite okay and even with all the CA, vignetting, soft corners and weird bokeh I still like it for it strange and different look. It also holds focus during zoom and focussing works well.

 

[Raul Gonzo]

Thanks Sander, I think it will do fine (for now). I would mostly need it for outdoor shoots anyway - so shooting it more closed is no problem.

 

[Dan Hudgins]

Flair and dynamic range...

Flair and dynamic range...

But the contrast of a multi-coated lens will still be higher, at any aperture.

Contrast is not always something you want, since the dynamic range of the REDONE is limited, under high contrast lighting soft flair (not hard reflections) can lift the shadow detail and let you stop down an extra stop or two, it reduces the dynamic range required.

When Cooke Series I lenses were the standard in Hollywood people were shooting Ortho film that was pushed to high contrast to get more speed, but the soft flair in the uncoated lenses helped flatten out the images so that the contrast was not too high. If they had been using super-multi-coated lenses the images would have been too hard and they would have had to cut back on the development and increase the exposure a stop or two which would have increased their electric bill 200% to 400% something the producers could not have tolerated.

I was supprised to see that Vantage has uncoated Zeiss (new?) superspeeds lenses for sale!

http://www.vantagefilm.com/file/pdf/vantage_uncoated_superspeeds.pdf

The older lenses were caculated so that the reflections would be out of focus since they were not coated, with the computer desigined lenses you can get in focus reflections (the maker assumes that the super-multi-coating will reduse the reflections), so I am not sure the Zeiss super speeds without coating is a good idea, has anyone tried them to see if there are in focus relfections?

The old rules of never pointing the lens into bright lights, keeping the sky out of the shot, and using a matte box closed down as much as possable were to control the flair and reflections in uncoated lenses, and for the most part worked as you can see in films made before WWII.

 

[Steven-Marc C.]

I bought a LOMO 37-140 T4.2 zoom for 350 US on Ebay. It might be comparable to the Lenar since they are both Russian, old and have similar zoom range. The LOMO is incredibly bad wide open on the long end. But as said, at T11 it is quite okay and even with all the CA, vignetting, soft corners and weird bokeh I still like it for it strange and different look. It also holds focus during zoom and focussing works well.

I also have a Lomo Foton 37-140. It is actually much more recent than that Lenar zoom since it dates from 1985. But it was sold as a cheap "beginner" zoom by Lomo. As Sander said, above 100-120mm, you get a very nice soft focus effect on the edges. I agree with Leo Ticheli that even an effect like that could become interesting in some (rare) cases. The problem with these lenses is not so much the optics (which have their own particular characteristics and that you can learn to use to your advantage) but the mechanics. If you have a bit of play in the focus and/or zoom rings, they become a real pain to use, especially on a Red One where focus is critical.

If you buy it, let us know how it behaves.

 

[Jorge Díaz-Amador]

The older lenses were caculated so that the reflections would be out of focus since they were not coated, with the computer desigined lenses you can get in focus reflections (the maker assumes that the super-multi-coating will reduse the reflections), so I am not sure the Zeiss super speeds without coating is a good idea, has anyone tried them to see if there are in focus relfections?

I think the main way the designers of pre Anti-Reflective coating (AR) lenses handled the problem is by using as few elements as possible since each air to glass surface pair would reduce the light transmission and increase flare by about 8%.

These simple designs also work brilliantly when coated. I have a five element Zeiss Sonnar 2.8/90mm for my Contax G2 that is the best portrait lens I have ever used and has beautiful bokeh.

I think that once you go below f2.0, you can't use that type of design anymore, and the Zeiss Super Speed (HS) primes are far more highly corrected.

How they polished the coating off all the elements on those HS f1.2 lenses and preserved the aspherical surfaces is something that remains a mystery...

 

[Steven-Marc C.]

Jorge, can a coating be added to a lens, or redone if it has cleaning marks?

 

[Douglas Underdahl]

In a previous lifetime when I worked at Panavision, Zeiss speeds were relatively new and Kodak was introducing sharper and more vivid film stocks. I spent a large part of my time removing black nets and snot tape from the backs of lenses. The manufacturers were going for sharpness and high contrast and the filmmakers wanted something else.

Now these Zeiss speeds with coatings removed! Of course, makes sense.

 

[David Rasberry]

Stephen -

I'm from that era. Shot a lot with old Angenieux zooms, some with side finders, even SOM Berthiots.

Douglas Underdahl
Author
THE 16MM CAMERA BOOK
contributor
THE AMERICAN CINEMATOGRAPHER MANUAL

Hi Douglas,

I have an old Angenieux 12-120 c-mount riding an Auricon thats been in storage for some years. it has the optical finder takeoff with a rigid top plate mounted viewfinder, reminiscent of some of the old Mitchell setups.

I am thinking of getting this overhauled and using it on a 2/3" Scarlet. It was in good clean condition optically and mechanically when I stored it. Shot some very nice footage with it years ago. It was my "blimped" studio camera alternate to a Bolex EBM for sound work. Cheap but functional.

Think its worth a try?

 

[Jorge Díaz-Amador]

Jorge, can a coating be added to a lens, or redone if it has cleaning marks?

I do this all the time. I even have a double-filtered laminar flow clean-air enclosure to put the glass back in, so no dust gets in the housings. Basically a mini clean-room. Even scratched elements can be re-coated. This is especially important on older lenses where new elements are no longer available from the manufacturer.

The actual polishing and coating are done by an outside contractor. They do not disassemble or assemble the lenses so the is no point in trying to go to them directly.

Break over... back to the clean room!

 

[David Rasberry]

Jorge,

Do you work on Angenieux lenses too?

 

[Douglas Underdahl]

David -

Oh yeah, it's worth a try. But I wouldn't spend money having it overhauled until you actually have a C mount Scarlet in hand. Once that happens, screw the 12-120 onto the Scarlet and see what you get. As I recall, they were pretty soft wide open, but when stopped down, they were quite sharp. By stopped down, I mean like 5.6 to 11. Probably give you a very 16mm movie film type look of that era.

And, think of all the C mount lenses that will pop up on eBay! Those Switars, the Angenieux 25mm F.095, that 1.9mm fisheye that was in DAVID HOLTZMAN'S DIARY - dirt cheap and loads of fun. Boy howdy.

 

[David Rasberry]

I was looking for the Angenieux f.095, but the price for the one I found was like $1300.00! I have a feeling the good C-mount stuff is going to take a jump in price with Scarlet's release.

I also have a set of Switars on an old Bolex spring wind turret mount.

By the way, still have a copy of your book stashed with the camera.

thanks

Razz

 

[Douglas Underdahl]

Cool, you've got the Switars - thanks Razz.

 

[Steven-Marc C.]

I do this all the time. I even have a double-filtered laminar flow clean-air enclosure to put the glass back in, so no dust gets in the housings. Basically a mini clean-room. Even scratched elements can be re-coated. This is especially important on older lenses where new elements are no longer available from the manufacturer.

The actual polishing and coating are done by an outside contractor. They do not disassemble or assemble the lenses so the is no point in trying to go to them directly.

Break over... back to the clean room!

Thanks, very instructive. Probably not worth it for the glass I had in mind, but always good to know.

 

[Dan Hudgins]

16mm lens vs. 2/3" sensor?

16mm lens vs. 2/3" sensor?

I have an old Angenieux 12-120 c-mount...

I am thinking of getting this overhauled and using it on a 2/3" Scarlet.

Think its worth a try?

Some 16mm lenses may cover a 2/3" sensor, but the Scarlet sensor seems wider than a 2/3" sensor spec? Does anyone know if there is an exact spec for 2/3" sensor width or diagonal?

See my post on the Kodak KAI-02150 sensor image circle for a link to its spec sheet.

Some of the numbers on the net vary but this is what I found,

Super16...=12.4mmx7.5mm
16mm......=10.4mmx7.5mm

2/3"sensor=8.8mmx6.6mm (less than 16mm wide)
Scarlet=10.1mmx5.35mm (about 16mm wide)

Projection 16mm is,

16mmproj=9.60mmx7.01mm (Scarlet is wider than the safe projection area)

So 2/3" is inside the 16mm projection, but Scarlet is wider by a little. 16mm film contact print was only about 400 lines high resolution at 80% MTF, so 16:9 crop in that will be maybe 320 to 360 lines at 80% MTF. Because of the limits of film the C mount movie lenses did not need to be very sharp. Newer 5 Megapixel 2/3" or 1" Machine Vision or Factory Automation lenses may have higher resolution than old 16mm movie lenses. With the OLPF the vertical resolution from a 3K sensor might get close to 1200 (or less), so the sensor would probably be higher than any 16mm movie lens wide open. I know from my work with 7360 and closed circuit cameras, that even good C mount movie lenses need to be stopped down to f/2.8 or so to get clean SD resolution, at f/1.4 you can see the circle of confusion is larger than an NTSC scanline.

So the Kodak sensor KAI-02150 is not quite "Super16" size?

Its 10.56mmx5.94mm with 5.5x5.5um pixels.

So if 2/3" is 8.8mm wide why is the Kodak sensor 10.56mm wide?

The Scarlet sensor is said to be 10.1mmx5.35mm, but that does not seem to be 16:9? So it is a odd shape for some reason?

Because the Scarlet sensor is wider than 8.8mm you might need to use 1" Megapixel lenses rather than 2/3" Megapixel lenses, it depends on how tight the image circle cuts off?

 

[Mitch Gross]

The whole sensor is not used. Look at the specs and do the math. 3.2 micron squares and it is 3072 pixels wide -- that's 9.83mm wide by my calculation. This is the same as on the RED One. The entire sensor is not used, although some is for the Look Around area.

 

[Larry McKee]

I have an Angenieux 9.5-57mm F1.6 zoom that I use for 2K work. My clients seem to really love the pictures it captures. Not tack sharp wide open, but very filmic, pretty images. I picked up an Angenieux 25mm F.95 in Arri Std mount that I plan to send to Jorge after the holidays to have him convert to PL. Should be a lot to fun to use.

 

[combatentropy]

Some 16mm lenses may cover a 2/3" sensor, but the Scarlet sensor seems wider than a 2/3" sensor spec?
...
Because the Scarlet sensor is wider than 8.8mm you might need to use 1" Megapixel lenses . . .

A lens shines a circle, but a chip is a rectangle. The measurement they share is the diagonal.

The diagonal for 16mm is about 11mm. So is 2/3".

8.8 x 6.6 is the old 2/3" standard. If you notice, its aspect ratio is 4:3. A widescreen (16:9) chip that would fit in the 11mm circle that 2/3" lenses make is about 10.1 x 5.35 --- longer horizontally, shorter vertically, still 11mm diagonally.

As for it not being exactly 16:9, it's best not to look too closely at pixel counts and sensor sizes. You'll ruin your eyes. You'll also waste your time, because most (maybe all) sensors reserve some pixels on the edges that never see light (used for calibration to the color black, as best as I understand it). And maybe some pixels see the light of day but not the inside of a memory card, because they are for "lookaround" --- to foresee a boom mic encroaching on your frame, just like in the film world.

 

[Dan Hudgins]

2/3" vs. 1" Megapixel lenses vs. 16mm Movie lenses...

2/3" vs. 1" Megapixel lenses vs. 16mm Movie lenses...

The diagonal for 16mm is about 11mm. So is 2/3".

If the "Old 2/3" and 16mm camera aperture are both 4:3 and their diagonal cannot be the same since their widths are not the same, 8.8mm vs. 10+mm.

Well 3K is 3072, so its not 3K if you use less than 3072? 16:9 is 3072x1728 so the active area should be taken from that?

If "old" 2/3" lenses use a little smaller diagonal then the "lookaround" area would have dark corners, and the 16:9 area might also be soft in the corners.

I'm too sleepy to make a detailed drawing of the image circle to see if the diagonal is longer than 11mm for the active area, is exactly 11mm the standard for all 2/3" lenses (do you have a link for that standard?)?

The Kodak data sheet puts the diagonal longer than 12mm, but I would have to see if the few extra pixels off makes it just 11mm for the 1920x1080 active area. At any rate the A-cam dII and Scarlet do not seem to be Super16 size sensors in the active area? At least not for Camera aperture size.

It's important to know because 2/3" Megapixel lenses may be sharper than 1" Megapixel lenses, but if you are going to get dark soft corners, you would want to go with 1" Megapixel lenses...

 

[combatentropy]

If the "Old 2/3" and 16mm camera aperture are both 4:3 and their diagonal cannot be the same since their widths are not the same, 8.8mm vs. 10+mm.

Right, 16mm camera aperture is a little bigger than 2/3" --- almost 13 mm. But its projector aperture, as you mentioned, is smaller, and only 11.4 mm.

All you have to do to find the diagonal is the old Pythagorean theorum: a^2 + b^2 = c^2.

Well 3K is 3072, so its not 3K if you use less than 3072? 16:9 is 3072x1728 so the active area should be taken from that?

I don't know. Is Red quoting 3K before or after taxes?

If "old" 2/3" lenses use a little smaller diagonal then the "lookaround" area would have dark corners, and the 16:9 area might also be soft in the corners.

The Scarlet sensor probably doesn't have lookaround area. The Red One does, but lookaround is typical to Hollywood cameras (S35), not news cameras (2/3).

is exactly 11mm the standard for all 2/3" lenses

I don't know. But any lens billed as 2/3" must cover at least 11mm.