P+S TECHNIK | Professional Cine Equipment Manufacture

PRO35 : Frequently Asked Questions

	1 \| Do I have to send my camera to P+S Technik to do some mechanical or electronic changes before I can use the PRO35 Image Converter? 2 \| How does the PRO35 work? 3 \| What do I basically need for a complete PRO35 Image Converter solution? 4\| What are the additional accessories you offer? 5 \| Which cameras work together with the PRO35? 6 \| Which lens mounts are available for the PRO35? 7 \| What does the image the PRO35 creates look like? 8 \| What is meant by "target"? 9 \| What kind of target (ground glass) is used in the PRO35? 10 \| Can I edit the same way? 11 \| Is there a light loss using the PRO35? 12 \| How do I get started? 13 \| Is it possible to start shooting with the PRO35 right away? 14 \| Do I need a power supply for the PRO35? 15 \| Why is there an ON/Off switch on the PRO35 Image Converter? 16 \| Why is there a speed control on the PRO35 Image Converter? 17 \| How to adjust the target's oscillation speed? 18 \| What is the iris in front of the B4-Mount of the Image Converter for? 19 \| How does the user adjusts the exposure (without affecting the depth of field)? 20 \| Is it possible to adjust exposure by the camera's shutter speed? What is to be considered in this case? 21 \| What is to be considered when shooting with variable frame rates (i.e. Panasonic "Varicam")? 22 \| Why is it not recommended to adjust exposure by stopping down the front lens aperture? 23 \| When testing different shutter speeds I realised that at 1/100 sec the structural pattern of the target becomes apparent. Which shutter speed do you recommend? 24 \| When stopping down the aperture of the front lens at T4.0 or further, the structural pattern of the target becomes apparent. How can I avoid this pattern to appear on my imagery? 25 \| Is it possible to use the whole tolerance of the film lens aperture together with the PRO35? 26 \| What is the highest aperture stop I can use without getting grain from the target? 27 \| I have got a colour gradient from top to bottom in my video image. What is it and what shall I do? 28 \| The distances engraved on the film lens's focus ring do not match to the measured distances to focused objects. Is it due to a back focus displacement? 29 \| How do I create a clean image? 30 \| Which support systems am I supposed to use with the PRO35 31 \| Why do I need a support system? 32 \| Which lenses can be used together with the PRO35? 33 \| Which lenses do you recommend to use and why? 34 \| Is it true that I have to use High Speed Prime lenses with the PRO35 and not the Standard Speeds? 35 \| Is it possible to use 16mm film lenses with the PRO35? 36 \| Does the focal length of the lens I’m using change? 37 \| Is the angle of view of the film lenses I'm using affected by the Image Converter? 38 \| Is the focal length or the angle of view of the photo lenses I'm using affected by the Image Converter? 39 \| How can I translate focal length for PRO35 in order to achieve similar angles of view compared to 35mm film, still photography and 2/3" video? 40 \| Is there a disadvantage between shooting with zoom lenses and shooting with prime lenses regarding the lens speed? 41 \| What focal length will we get using Nikkor 15mm? 42 \| Regarding stills lenses: does any of the manufacturers you support provide sets of prime lenses or do they all tend to go for the zoom lenses. 43 \| Will we have aberration of the image or any problems with black edges (vignetting)? 44 \| Is it possible to use a PRO35 between a complete series of Nikon 35mm photo lenses ((20,28,35,50,80,180mm) and a Sony HDCAM 750? 45 \| The PRO35 does not start ? What can I do? 46 \| Can I replace the target (ground glass) of the PRO35 if it is broken? 47 \| Is there any place other than Germany where I can buy this equipment?
	1) Do I have to send my camera to P+S Technik to do some mechanical or electronic changes before I can use the PRO35 Image Converter? No, there is no need for any modifications, therefore there is no need to send the camera to us.

	2) How does the PRO35 work? The basic principle: The PRO35 achieves a mechanical and optical adaptation of 35mm film lenses to any commercially available 2/3" broadcast video camera (Standard and High Definition) with a Sony B4-Mount. How does the PRO35 works: The chip size (image field) of your 2/3" - camera is artificially enlarged by an intermediate projection, therefore transferring the 35mm lens characteristics (e.g. angle of view and depth of field) to the video camera. The deciding point is the two stage configuration: The image, drafted by the film lens is projected onto an oscillating ground glass, called target. This target is in the same position, as the film plane in a 35mm film camera. For this reason the scale of reproduction, as well as depth of field and angle of view show the "film like quality", similar to a 35mm film camera. In a second step this real image is resized and projected onto the CCD - video chip. Since this is just a linear squeeze of a two-dimensional image all optical characteristics like depth of field and angle of view stay the same. This means that the video chip is not the place of image creation (this is the target!), but of image recording.
	3) What do I basically need for a complete PRO35 Image Converter solution? The PRO35 is delivered by default with a Sony B4-Mount camera sided, a ARRI PL-Mount lens sided and a light weight support system [FAQ support systems]. Therefore you just need the PRO35 Image Converter for a complete PRO35 solution. We explicitly recommend the use of a remote switch in order to guarantee an easily operated start and stop of both, camera and Image Converter simultaneous. Corresponding switches are available from P+S Technik, ARRI and other suppliers. For further information please refer to [TecDoc No. ###]
	4) What are the additional accessories you offer? Additional accessories, like different [lens mounts], heavy duty support system (19mm) and plenty of power supply cables are available. [Zubehör] For further information please refer to [Datasheet PRO35].
	5) Which cameras work together with the PRO35? All 2/3" B4-Mount video cameras (Standard Definition & High Definition) work together with the PRO35.
	6) Which lens mounts are available for the PRO35? The following lens mounts are available for the PRO35: * PL Mount (standard edition) * Panavision Mount * BNC-R Mount * Nikon Mount * Canon Mount (EF mount) * Contax Mount Please note: The PRO35 mounts are not designed for quick change (like the ones for the MINI35 are). Especially after assembling a film lens mount to the PRO35 an adjustment on a collimator is necessary.
	7) What does the image the PRO35 creates look like? Basically the PRO35 makes a limited depth of field possible for 2/3" video cameras as up to now it was applicable only in connection with 35mm film. Thereby the PRO35 enables film-makers to use limited depth of field as another creative instrument for shooting on video. At the same time the targets structural pattern affects the image comparably to a light soft-focus and low-contrast filter and adds a [FAQ: Why ON/OFF switch- film grain-like effect] to it. In contrast to a textbook-perfect, hard and clean digital video, the PRO35 generates images, appearing more lively and softer. Altogether the look and feel is similar to the imagery you are used to from 35mm film.
	8) What is meant by "target"? The "target" is the core of the Image Converter. It is a grinded optical glass, similar to a ground glass, used in viewfinder systems of film cameras. The image, drafted by the film lens, is projected onto this target and in a second step captured by the CCD-chip of your video camera. In order to blur the target's structural pattern it is set into an oscillation movement.
	9) What kind of target (ground glass) is used in the PRO35? The target, used in the PRO35, is a specially grinded optical glass, that minimizes light loss.
	10) Can I edit the same way? Yes. You can edit the same way you are used to.
	11)Is there a light loss using the PRO35? Yes, for the PRO35 you can assume a light loss of 1.5 stops. Since the light loss is not linear this is the "worst case" value.
	12 )How do I get started? Since shooting with the PRO35 is similar to shooting with film, we recommend to test the complete setup in detail in order to familiarize with your Image Converter and its specific features! For setup details please refer to the [User Manual]
	13) Is it possible to start shooting with the PRO35 right away? Yes, this is possible, but since shooting with the PRO35 is similar to shooting with film, we recommend to test the complete setup in detail in order to familiarize with your new Image Converter and its specific features! Please mind the necessity of [TecDoc.: Back focus] and [TecDoc No. Colour Shading] adjustment. For setup details please refer to the [User Manual]
	14) Do I need a power supply for the PRO35? Yes, you need a power supply to run the motor of the PRO35 for the oscillation of the target. The PRO35 is delivered by default with a power supply cable for the lens connector (Hirose 12-pin/ Fischer 7-pin) on the camera. This allows you to use the same battery for the PRO35, you run your camera with. Over and above plenty of alternative power supply cables are available to use different power and battery systems (i.e. with Anton Bauer, Digibeta Hirose or XLR connectors). For further information please refer to our [Price list].
	15)Why is there an ON/Off switch on the PRO35 Image Converter? As specified in FAQ [How does the PRO works] the image generated by the 35mm front lens is projected in a first step onto a ground glass-like target. In a second step this image is resized by a relay lens system to the smaller-sized video chip. The target itself carries a structural pattern to visualize the image created by the front lens. If the target is motionless, this pattern is stamped on the image and appears like some kind of dirt on the lens [Picture]. In order to blur this structural pattern the Image Converter has to be switched on. The target starts oscillating whereby the structural pattern appears in a film grain-like manner. [Picture]
	16) Why is there a speed control on the PRO35 Image Converter? As specified in FAQ [how does the pro works] the image generated by the 35mm front lens is projected in a first step onto a ground glass-like target. In a second step this image is resized by a relay lens system to the smaller-sized video chip. The target itself carries a structural pattern to visualize the image created by the front lens. If the target is motionless, this pattern is stamped on the image and appears like some kind of dirty on the lens [Picture]. In order to blur this structural pattern the target is set into an oscillating movement, whereby the structural pattern appears in a film grain-like manner. [Picture] The speed control now diversifies the target's oscillation frequency. This provides the opportunity to eliminate disturbances or interferences caused by high shutter speeds or to achieve different grain effects, also depending upon the iris opening of the front lens. [FAQ Einfluss der Frontblende auf den grain effect] For information on the right adjustment of the target speed please consult [TecDoc No. 69: Pro35_adjust Target-Speed]
	17) How to adjust the target's oscillation speed? For information on the adjustment of the target's oscillation speed please consult [TecDoc No. 69: Pro35_adjust Target-Speed]
	18) What is the iris in front of the B4-Mount of the Image Converter for? The PRO35 is equipped with an iris. However this iris only serves to light reduction. This offers the opportunity to shoot in bright environments with a wide opened front lens aperture (in order to obtain a narrow depth of field) without overexposing the video cameras CCD-chip. Therefore the Image Converter's iris is comparable to a variable ND function. But there is no influence on depth of field, because the light source, relating to this iris is no three-dimensional environment, but the two-dimensional image on the target, which obtains just one focus plane. That is why the depth of field isn't influenced by the Image Converter's iris. In summary: For a camera setup with the PRO35 Image Converter the aperture of the front lens serves to adjust the images depth of field; the iris of the Image Converter only serves to adjust exposure.
	19) How does the user adjusts the exposure (without affecting the depth of field)? In order to control exposure (i.e. when light is too intense like in bright daylight) without affecting the depth of field we recommend to use the iris of the Image Converter. [FAQ INTERNE BLENDE]. If this ND function is insufficient and the image remains overexposed, closing the film lens iris may not offer the required limited depth of field or may project too much grain on the video image. Two possible remedies: 1) Use the ND function of your video camera or 2) Use a ND filter in front of the film/photo lens to decrease the light entering the system We do not recommend to increase the shutter speed of the camera in order to control exposure. In this case please consider, that the visibility of the targe'ts structural pattern changes and might cause disturbance or interferences in your image. Although it's possible to eliminate these interferences by adjusting the speed control of the target. For further information please refer to [FAQ ### (Shutter Speed und Mattscheibengeschwindigkeit einstellen] order [TecDoc No. 69: Pro35_adjust Target-Speed (Florian Rettich)].
	20) Is it possible to adjust exposure by the camera's shutter speed? What is to be considered in this case? When decreasing the shutter speed of your camera in order to control exposure please consider, that the visibility of the target's structural pattern changes and might cause disturbance or interferences in your image. Please refer to [FAQ ### (Shutter Speed und Mattscheibengeschwindigkeit einstellen)] or [TecDoc 61: PRO35 variable framerates]
	21) What is to be considered when shooting with variable frame rates (i.e. Panasonic "Varicam")? When decreasing the shutter speed of your camera in order to shoot at variable (higher) frame rates, please consider, that the visibility of the target's structural pattern changes and might cause disturbance or interferences in your image. By adjusting the target's speed control it is possible to eliminate these interferences. For further information please refer to [TecDoc No. 61: PRO35 variable framerates]
	22) Why is it not recommended to adjust exposure by stopping down the front lens aperture? There are different reasons: 1) The higher the T-stop (T4.0 or higher i.e. T11), the more apparent the grain effect will be. The other way around: the lower the T-stop (T4.0 or lower i.e. T1.2), the less apparent the grain effect will be. 2) When closing the front lens aperture more than about 2.5 stops, the depth of field is comparable to a normal video lens. In this case it makes no sense shooting with the PRO35 and film lenses. In order to control exposure it is more advantageous to use the Image Converter's or the camera's ND function [FAQ ND function].
	23) When testing different shutter speeds I realised that at 1/100 sec the structural pattern of the target becomes apparent. Which shutter speed do you recommend? We recommend to use standard shutter speeds with the current version of the PRO35. For further information please refer to [TecDoc No. 61: PRO35 variable framerate] and [TecDoc No. 69: Pro35_adjust Target-Speed]
	24) When stopping down the aperture of the front lens at T4.0 or further, the structural pattern of the target becomes apparent. How can I avoid this pattern to appear on my imagery? In order to control exposure (i.e. when light is too intense like in bright daylight) without affecting the depth of field, we recommend to use the iris of the Image Converter. [FAQ INTERNE BLENDE]. If this ND function is insufficient and the image remains overexposed, closing the film lens iris may not offer the required limited depth of field or may project too much grain on the video image. Two possible remedies: 1) Use the ND filter of your video camera or 2) Use a ND filter in front of the film/photo lens to decrease the light entering the system We do not recommend to increase the shutter speed of the camera in order to control exposure. In this case please consider, that the visibility of the target's structural pattern changes and might cause disturbance or interferences in your image. Although is possible to eliminate these interferences by adjusting the speed control of the target. For further information please refer to [FAQ ### (Shutter Speed und Mattscheibengeschwindigkeit einstellen] order [TecDoc No. 69: Pro35_adjust Target-Speed(Florian Rettich)].
	25) Is it possible to use the whole tolerance of the film lens aperture together with the PRO35? We advise not to use the whole tolerance of the film lens aperture together with the PRO35. Stopping down the aperture of the front lens at T4.0 or further unveils the structural pattern of the target. In order to control exposure (i.e. when light is too intense like in bright daylight) without affecting the depth of field, we recommend to use the Image Converter's iris. [FAQ INTERNE BLENDE].
	26) What is the highest aperture stop I can use without getting grain from the target? We recommend to avoid stopping down the front lens aperture further than T4.0.
	27) I have got a colour gradient from top to bottom in my video image. What is it and what shall I do? This is so called "colour shading", a gradual shift of the colour in upright direction due to a mismatch of the lens system and the electronic system of the camera. To get further information on this phenomenon and how to eliminate it, please refer to [TecDoc No. 54: Adjustment of the color shading PRO35 image converter]
	28) The distances engraved on the film lens's focus ring do not match to the measured distances to focused objects. Is it due to a back focus displacement? Yes. You have to adjust the back focus at the Image Converter. For the adjustment please refer to the [User Manual]
	29) How do I create a clean image? For creation of a clean image please consider the following items: * Back focus adjustment - a step by step guide is to be found in the [User Manuel]. * Colour Shading adjustment - please refer to [TecDoc No. 54: Adjustment of the color shading PRO35 image converter] * adjust the target's oscillation speed - please refer to [TecDoc No. ### Target speed einstellen] * control the camera's shutter speed - please refer to [TecDoc No. 61: PRO35 variable framerate] * do not stop down the front lens further than T4.0 * Try setting the camera to manual mode and limit the gain to 0 db or even –3 db
	30) Which support systems am I supposed to use with the PRO35? * by default the PRO35 is delivered with a 15mm light weight support system, including the required support bridge and two 15mm rods. PLEASE NOTE: to connect this leight weight support system to your 2/3" video camera you need a bottom plate, prepared for light weight support! [Bild oder neues Tec Doc??] * for heavy duty support with the PRO35 please refer to [TecDoc No. 49: Pro35 - 19mm support] and [TecDoc No. 50: Pro35 - Arri based 19mm support]
	31) Why do I need a support system? * In order to stabilize your setup and take weight of the video camera's B4 mount. * offers the possibility to connect accessories like matte box or follow focus to your PRO35 setup
	32) Which lenses can be used together with the PRO35? You can use all available film lenses with PL-Mount, able to expose the N35 Academy format (22mm x 16mm): * Zeiss Master Primes (T1.3) * Zeiss Ultra Primes (T1.9-T2.8) * Zeiss Super Speed Lenses (T1.3) * Cook S4 * Cook S4 Zoom T2 15-40mm * Cook Zoom T3 18m-100mm * Angenieux Optimo Zooms * Zeiss Distagon: (focal length 85mm or more!) ATTENTION! Zoom lenses and Zeiss Distagon lenses might cause vignetting. These lenses should be tested before shooting individually! Furthermore the following lens mounts are available and can be used with the corresponding lenses: * Panavision Mount * Nikon Mount * Canon EF Mount * Contax Mount * BNC-R Mount
	33) Which lenses do you recommend to use and why? The following lenses work perfectly with the PRO35: * Zeiss Master Primes * Zeiss HS Primes * Cook S4 * Zeiss Ultra Primes You always have to keep in mind, that you have a light loss of 1.5 stops with the PRO35. The faster the lens, the more light is left for exposure! Over and above a wide opened front aperture creates a smaller depth of field.
	34) Is it true that I have to use High Speed Prime lenses with the PRO35 and not the Standard Speeds? No, it is not true that you have to use Zeiss High Speed primes. The advantage of the HS lenses is the fact, that with a T 1.3 the HS lenses have a bigger aperture and accordingly a smaller depth of field than standard speed lenses. Although you can use other lenses, i.e. Ultra Primes or photo lenses: It is important to check each lens before shooting, because you never know what could happen. That is what camera assistants do before shooting with film cameras and it should be the same before shooting with a PRO35 and film or photo lenses.
	35) Is it possible to use 16mm film lenses with the PRO35? The PRO35 is developed for the use with 35mm film lenses, that expose the whole N35 Academy format. Since 16mm lenses are styled for smaller frame sizes, vignetting problems may occur. As a rough guide 16mm lenses, whose rear lens is as large as a one €uro coin should work. But if you decide to use 16mm lenses, please test it before shooting!
	36) Does the focal length of the lens I’m using change? No, the focal length of the lens does not change. It stays the same!
	37) Is the angle of view of the film lenses I'm using affected by the Image Converter? Neither the focus length nor the angle of view is affected by your Image Converter. For all 35mm film lenses the image properties comply with the properties of a N35 film camera. For further understanding: In principle every 35mm film lens draws a round image onto the film gate of a film camera (most 35mm film lenses draw an image diameter of 30mm in order to expose S35 formats as well as N35 formats, although a diameter of 27,2mm suffices to expose the N35 formats). This film gate or an accordant format mask cuts out the framing as desired. For the PRO35 it's nearly the same: The fore part of the Image Converter is designed simular to a N35 film camera [FAQ Funktionsprinzip]: The film lens draws a round image onto the Image Converter's target, which is in the same position as the film stock in a film camera. In a second step a 27,2mm image circle (remember: this is satisfactory for N35 formats!) is then squeezed to the diameter/diagonal (11 mm) of the 2/3" CCD-chip. The CCD-chip then serves as a quasi format mask and cuts out the framing according to the CCDs size. [Beispielzeichnung]. In conclusion it is to say that the CCD-chip defines, what is recorded by the video camera!
	38) Is the focal length or the angle of view of the photo lenses I'm using affected by the Image Converter? The focal length of your photo lenses is not affected by the PRO35. Stills Photographers: Compared to still photography the angle of view changes (gets smaller!). In order to choose the right focal length for a desired angle of view please refer to [Translate Focal length]. Cinematographers: If you are used to shoot on film lenses, you can handle a photo lens the same way like a film lens. I.e.: on the PRO35 the angle of view (as well as the focal length and depth of field) of a 50mm photo lens is the same as of a 50mm film lens! Differences remain in order to the handling (i.e. focus).
	39) How can I translate focal length for PRO35 in order to achieve similar angles of view compared to 35mm film, still photography and 2/3" video? In order to achieve same angles of view with the PRO35 please use the following factors starting from * 2/3" video; 4:3 [Standard lens: 13 mm]: Factor: 2,4 * N35 film 4:3 [Standard lens: 32 mm]: Factor: 1 * 2/3" video; 1:1,78 [Standard lens: 11 mm]: Factor: 2,3 * N35 film; 1:1,78 [Standard lens: 25 mm]: Factor: 1 * Stills Photography full format [Standard lens: 48 mm]: Factor 0,67 Please note: The standard focal lengths are based on a vertical visual angle of 28°
	40) Is there a disadvantage between shooting with zoom lenses and shooting with prime lenses regarding the lens speed? Yes, the disadvantage is the speed of the different lens types. Due to the optical design of zoom lenses you usually get less light through a zoom lens to the chip, compared to a prime lens. The loss of light can be handled by opening the lens's iris or putting up more light sources. We recommend to use prime lenses, because you always have to keep in mind, that there's a light loss of 1.5 stops with the PRO35. The faster the lens, the more light is left for exposure! Over and above a wide opened aperture creates a smaller depth of field.
	41) What focal length will we get using Nikkor 15mm? It will be also 15mm! But please note: The angle of view will change in comparison to 35mm still photography. For further information please refer to [FAQ Translate focal length] and [FAQ Focal length of stills lenses]
	42) Regarding stills lenses: does any of the manufacturers you support provide sets of prime lenses or do they all tend to go for the zoom lenses. They do both, zoom lenses and prime lenses. But Nikon seems to be the only manufacturer that still produces photo lenses with real mechanic focus adjustment. Other lenses are manufactured with auto focus function which is of no use with our products. But it is possible to find used prime lens sets in very good condition of Canon and other lens manufacturers.
	43) Will we have aberration of the image or any problems with black edges (vignetting)? No, if you use recommended lenses you won't have any such problems! If you use other lenses please test them before shooting!
	44) Is it possible to use a PRO35 between a complete series of Nikon 35mm photo lenses ((20,28,35,50,80,180mm) and a Sony HDCAM 750? Yes, this is possible!
	45) The PRO35 does not start ? What can I do? Background: The PRO35 starts when the VTR signal goes to LOW Level on the lens connector (tested on Digibeta, Beta SP and Panasonic). Some cameras do not go to LOW Level when pushing the VTR button. We do not know whether this is a typical problem for a certain camera model or only for some single cameras. Solution: Connect a remote switch (like "RS switch" (#20499) from P+S Technik) to the PRO35 Image Converter (3-pin Fischer). Then you can start the camera (VTR) and the PRO35 simultaneously. This is the method preferred by most DPs. Alternative switches are available from ARRI ("RS-4") and other suppliers. [Tec. Doc No. ??]
	46) Can I replace the target (ground glass) of the PRO35 if it is broken? Yes, it is possible to replace the target. There are two possibilities: 1) You can send us the broken Image Converter and we replace the target for you. 2) You can order a new target and replace it on your own. In this case the warranty expires. For detailed information and a step by step instruction please read [Link: TecDoc No. 67: ]
	47) Is there any place other than Germany where I can buy this equipment? We have several local dealers. You can download the actual listing from our website [Link: Dealer list]

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