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anamorphic lenses through abakus onto a 2/3rd chip


thomas-english

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I really was not sure where to post this since it spans so many topics.

 

Shooting a promo soon and I am really considering using an abakus adaptor to use 35mm anamorphics onto a b4 mount 2/3rd camera.

 

I appreciate there is no ground glass etc etc and we are simply photographing the middle of the projected image but

 

a 50mm lens is a 50mm lens. giving FOV of a 25mm lens anamrpically whatever the gate, so I will have the 25mm 2/3rd equivilant FOV?

 

I will still get the nice flares etc?

 

Am I mad? are there any reasons I should not go for it and run a test?

 

Where can I get an abakus adaptor from?

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your probably right David on second thoughts.

 

So I just need to do a test, wacking a regular 35mm anamorpic onto the front of a sony mount. I appreciate that the film plane is flat and I should be catering for our 3 colour chips but hey ... it s a promo... am I mad? will it work or just garble? is it worth going to the trouble and testing?

 

thanks for your time

 

thomas

 

N.B. by promo I mean music video

Edited by thomas-english
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I did this once, put an anamorphic cine lens on a Varicam by using the P&S Pro-35 adaptor. You just have to deal with the fact that you will have a 2X squeezed image onto a 16x9 (1.78 : 1) sensor and what to do with that in post. Unsqueezed, you'd have a 3.56 : 1 letterboxed image. Or you can frame for cropping the sides back down to something more reasonable like 2.35 : 1 (you could basically use the standard 4x3 crop marks in the 16x9 viewfinder as a guide.)

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sure, I am planning/hoping not to use the pro35 (although I use this often). I don t want that perfect look and can t use that much light seeing as I will then have to light to 5.6 @ 320asa (I suppose thats not that grevious). I am hoping to simply use the middle of the anamorphic lens and have my 2x squeeze anyway.

 

I am thinking of simply getting or having made a pl to b4 adaptor

 

Ill be honest, it s a 15 grand promo, I am messing about with kit here and not too bothered with massive cock ups 'cause it s art. if it don t work, ill stop shooting with those lenses! but it s a lot of hassle for me getting the adaptor made and getting to panavision for a whole day etc etc thats why I really appreciate this forum and your time David.

 

People use 35mm anamorphics on s16? no probs.. your just using the middle of the lens and have the s16 FOV through lthat lens. your certainly going to cover the whole chip rather than trying to use an anamorphic on a ps techniks.

 

Using film lenses direct onto the video gate will give me chromatic aberations of sorts... are these seriously noticable? I am after a funny look here but I think if the colours are splitting badly this would not be a good thing.

 

I have never tried putting a flat plane lens on a b4 mount, but Les Bosher reckons its acceptable to stick a b4 lens onto a flat plane camera (s16) without any further optics. although obviously it vignettes seriously. clearly he says its no good for the big screen, but for a promo it s totally fine.

 

Has anyone ever actually tried sticking a film lens straight on to a video camera?

 

To make things more the irritating, off course I am going to use an HD body, 750 or 900. Delivery on promo s is being demanded at FHD (what the hell does that mean, full high def?) from the end of january onwards in the UK. but clearly broadcast of this is going to be SD.

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There is a simple Canon adaptor (PL-to-B4), I believe, but the problem is that the image has to be flipped in the camera, unless you want to watch (I think) an upside-down image or mirrored, I can't remember how it needs to be flipped or flopped.

 

But I don't think you can simply stick the lens onto the camera, not without some serious machine-shop work... not to mention the flange-depth issues.

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with regards to your above points... yeah.. it will be a long old picture. Ill set my marrel framelines up as you say and use the anamorphic funtion on my transvideo monitor. I am shooting this on the AR mk-v rig

 

www.thomasenglish.co.uk/ar

 

but now you mention all the other data I am going to have on each side... wow... I had forgotten about that.. the director is going to love the ability to "bounce the frame" in post... he s going to love that.. makes me want to make this work all the more.

 

I suppose I could try and source some of the anamorphic superspeeds for the techniks... but really want to be sure I can t get away with plonking a film plane lens on a video camera.

 

 

 

I can flip and flop all I like on the transvideos....

 

oh yeah.. the director... hmmm

 

yeah, you might be right about al the flanges and focus distances... that s were the main problems are going to be. It could end up costing a third of the cost of the promo!

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I did this once, put an anamorphic cine lens on a Varicam by using the P&S Pro-35 adaptor. You just have to deal with the fact that you will have a 2X squeezed image onto a 16x9 (1.78 : 1) sensor and what to do with that in post. Unsqueezed, you'd have a 3.56 : 1 letterboxed image. Or you can frame for cropping the sides back down to something more reasonable like 2.35 : 1 (you could basically use the standard 4x3 crop marks in the 16x9 viewfinder as a guide.)

 

Wouldn't cropping the 3.56 to 2.35 yield the same results as just cropping the 16:9 frame to 2.35? I mean you lose resolution on both right? If you had a 1.33x anamorphic then there could maybe be an advantage.

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Wouldn't cropping the 3.56 to 2.35 yield the same results as just cropping the 16:9 frame to 2.35? I mean you lose resolution on both right? If you had a 1.33x anamorphic then there could maybe be an advantage.

 

Yes, the only reason would be to get the anamorphic lens artifacts and distortions, not for extra resolution, since the final product would have to be letterboxed anyway if wider than 16x9.

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Yes, the only reason would be to get the anamorphic lens artifacts and distortions, not for extra resolution, since the final product would have to be letterboxed anyway if wider than 16x9.

 

How about if using a 1.33x(in case a sharp enough lens at that ratio existed)? With that ratio, nothing would need to be cropped to obtain a 2.35 aspect ratio.

Would it somehow enhance the resolution? Let?s say a 1.33x on a Varicam or F900.

Just wondering if it would be the same as with film.

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How about if using a 1.33x(in case a sharp enough lens at that ratio existed)? With that ratio, nothing would need to be cropped to obtain a 2.35 aspect ratio.

Would it somehow enhance the resolution? Let’s say a 1.33x on a Varicam or F900.

Just wondering if it would be the same as with film.

 

Well it would still have to be converted to a 2.35 letterboxed image for display, so the end resolution is limited by that. I don't think there would be any resolution improvement over simply letterboxing a spherical 16x9 HD image -- there's no "loss" in letterboxing if the display device isn't enlarging the picture area inside the letterbox to fill a TV screen. The overall screen resolution is the same only that part of the image contains black bars. Any gains in "oversampling" to create a 2.35 letterboxed HD image by using an anamorphic lens and later resizing would be offset by the optical loss of whatever system you used to get the anamorphic image, versus using the best spherical HD lenses out there.

 

The only advantage of using a 1.33X anamorphic lens on a 16x9 HD camera in terms of resolution is if you were going to do a film-out to 35mm anamorphic.

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Well it would still have to be converted to a 2.35 letterboxed image for display, so the end resolution is limited by that. I don't think there would be any resolution improvement over simply letterboxing a spherical 16x9 HD image -- there's no "loss" in letterboxing if the display device isn't enlarging the picture area inside the letterbox to fill a TV screen. The overall screen resolution is the same only that part of the image contains black bars.

 

Yeah, but for digital projection, unless you enlarge the 2.35 frame to fill the screen it will most likely look too small if the black bars are what touch the upper and lower boards of the screen. For TV/DVD the letterbox would be totally fine since that?s how we watch 2.35 movies on DVD anyway.

 

Any gains in "oversampling" to create a 2.35 letterboxed HD image by using an anamorphic lens and later resizing would be offset by the optical loss of whatever system you used to get the anamorphic image, versus using the best spherical HD lenses out there.

 

I kind of lost you here. What optical loss?

 

 

The only advantage of using a 1.33X anamorphic lens on a 16x9 HD camera in terms of resolution is if you were going to do a film-out to 35mm anamorphic.

 

How about if finishing the movie leaving it squeezed and then used the ?same? 1.33x lens to project it in 2.35:1? Would that yield any resolution gains? That?s another option.

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I kind of lost you here. What optical loss?

How about if finishing the movie leaving it squeezed and then used the ?same? 1.33x lens to project it in 2.35:1? Would that yield any resolution gains? That?s another option.

 

Optical loss like having to use the P&S Technic or other methods of putting cine lenses on HD cameras.

 

Well, the older 1.2K DLP Cinema projectors did scope this way, sort of. The DMD chip was nearly square so 1.5X anamorphic lenses were used to project 16x9 material or 1.85 movies, and 1.9X anamorphic lenses were used to project 2.35 movies where the image had a 1.33X squeeze to fill 16x9.

 

But now with 2K DLP Cinema, the projector lenses are spherical and you just vary the vertical height to change aspect ratios.

 

In other words, there is no point shooting for a projection format that isn't being used.

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Optical loss like having to use the P&S Technic or other methods of putting cine lenses on HD cameras.

 

Oh, I see what you meant now. Well, in case one would be using a P&S Technic adapter for the 35mm shallow dof and fov anyway with spherical lenses, the anamorphics would at least get them more resolution if the intended aspect ratio was 2.35:1. It wouldn?t look any softer than the P&S with sphericals. Actually, since he wouldn?t need to crop to obtain the 2.35:1. it would probably look sharper than the P&S cropped spherical footage, no?

That of course if 1,33x or 1,5x anamorphic lenses existed or if an anamorphic front adapter was used. 16mm and even 35mm front anamorphic lenses are fairly easy to find in 1,33x and 1,5x and I think would be sharp enough for that application since they resolve 16mm and 35mm.

 

Well, the older 1.2K DLP Cinema projectors did scope this way, sort of. The DMD chip was nearly square so 1.5X anamorphic lenses were used to project 16x9 material or 1.85 movies, and 1.9X anamorphic lenses were used to project 2.35 movies where the image had a 1.33X squeeze to fill 16x9.

But now with 2K DLP Cinema, the projector lenses are spherical and you just vary the vertical height to change aspect ratios.

In other words, there is no point shooting for a projection format that isn't being used.

 

Yeah. But in case one really wanted, couldn?t he still take advantage somehow of shooting real anamorphic by not decompressing the image in post and using the same anamorphic front lens he used to shoot for projection? The same lens would then project it in the right aspect ratio.

Just all speculation. Just trying to see if it?s possible to take advantage at all from anamorphic photography in HD.

As you said, if going to film, there would definitely be an advantage because then it could be decompressed by the film projector the same way film originated anamorphic photography is done. But I?m speculating if staying in digital realm.

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Oh, I see what you meant now. Well, in case one would be using a P&S Technic adapter for the 35mm shallow dof and fov anyway with spherical lenses, the anamorphics would at least get them more resolution if the intended aspect ratio was 2.35:1. It wouldn?t look any softer than the P&S with sphericals. Actually, since he wouldn?t need to crop to obtain the 2.35:1. it would probably look sharper than the P&S cropped spherical footage, no?

 

Not with standard 2X anamorphic cine lenses, where you'd be cropping 3.56 horizontally down to 2.35, as opposed to using spherical lenses and cropping 1.78 vertically to get to 2.35.

 

Again, if the end product is for video distribution where you only have two display formats, 4x3 and 16x9, anything 2.35 would require letterboxing anyway. There is no resolution "loss" in letterboxing unless you are trying to enlarge the picture area INSIDE the letterbox to fill something larger.

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Not with standard 2X anamorphic cine lenses, where you'd be cropping 3.56 horizontally down to 2.35, as opposed to using spherical lenses and cropping 1.78 vertically to get to 2.35.

 

Again, if the end product is for video distribution where you only have two display formats, 4x3 and 16x9, anything 2.35 would require letterboxing anyway. There is no resolution "loss" in letterboxing unless you are trying to enlarge the picture area INSIDE the letterbox to fill something larger.

 

Yeah, that's why I mentioned doing it with a 1.33x or 1.5x adapter or something. I know for 2x you would still need to crop. But 1.33x would give you a nearly perfect aspect ratio at 2.36:1 and even 1.5x could be used without cropping at 2.66:1. Full Cinemascope :D

 

Also, any comments on the second paragraph of my prior post?

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Also, any comments on the second paragraph of my prior post?

 

Until 1.33X anamorphic HD projection is commonplace, I don't see the point in shooting 1.33X anamorphic unless for a film-out to 35mm scope, maybe 2K digital projection (but I would want to test that.) But it all depends on the advent of 1.33X lenses (which I have been waiting for.)

 

The Viper, by the way, in 2.35 mode, basically creates an electronic 1.33X squeeze onto the 16x9 recording by the way it remaps the sensor sites on the CCD's.

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The Viper, by the way, in 2.35 mode, basically creates an electronic 1.33X squeeze onto the 16x9 recording by the way it remaps the sensor sites on the CCD's.

 

 

Is it any better than just cropping the 16:9 frame to 2.35:1?

Sounds like the work around DV cameras had before 16:9 chips became commonplace, which not always produced better results than just cropping.

I think with the release of more and more single sensor 16:9 HD cameras like the Genesis, RED etc, 1.33x anamorphic lenses will eventually come.

Edited by Michael Maier
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Is it any better than just cropping the 16:9 frame to 2.35:1?

 

Yes. Each sensor site on the Viper CCD's is made up for four sub-pixels, which allows the camera to rearrange the sensor sites to handle different aspect ratios while keeping the same pixel resolution. So a 2.35 image is alloted all 1920 x 1080 pixels for capture and recording.

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