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David Hessel

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David Hessel last won the day on October 25 2018

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  1. No they are the same. The micro 4/3 may have less light coming in overall but it has the same amount of light relative to the surface area of the sensor as the full frame setup. Another way to look at it is the F stop is the density of light produced by the lens, different lenses on different formats may have different amounts of light coming in but the denisty of light at the sensor/film plane is the same if the F stop of the lenses have is the same.
  2. The taking lens for the Iscorama is meant to be at infnity always so it is set to Infinity focus with no focus ring. There is no point in having a focus ring on this lens since the the focusing is all handled via the anamorphic front. If it is not focusing at infinity then either your camera/mount adapter is out of spec or the lens needs to be collimated. The thing is anamorphic lenses like these require proper collimation, the anamorphic front and taking lens must be focusing in synch to get a sharp image. The front anamorphic block is set to infinity and is focused using a variable strength diopter infront of the anamorphic block, the taking lens must also be set to infinity to get a sharp image. I have don't know how to go about adjusting the focus on that lens but it will be difficult without a collimator. This is probably a job for a lens tech but if you want to try yourself you can make a DIY collimator using an old film camera. I did this a while back to fine tune the adjustmens for a anamorphic lens that I have. First I attached a lens to an old film camera and focused to infinity using the VF. Next I locked the focus at infinity so I could no longer change it by accident. Then I removed the shutter leaving the hole where the film would be exposted. I then made a focus chart using a printer and mounted that behind the hole where the film would be. I mount this camera and lens on rails infront of the lens I want to adjust that is attached to another camera so I can view its output. The cameras are setup so that the lenses are face each other. Last I placed a light behind the film camera with the film door open. You just look at the output from the camera with the lens you are adjusting and adjust the focus until you have a sharp image of the chart at infinity. This is definately not the most accurate way of doing it but was the best DIY solution I could readily come up with.
  3. First if you convert 12 bit to 10 bits you end up with 10 bits of data. The bit depth determines the number of values a color channel can store so 12 bit has 4096 possilbe values and 10 bit has 1024 possible values regardless of whether it is log or not. The logic for storing visual data in a log curve, as I understand it, is the eye doesn't respond to increasing brightness of light in a linear way. Roughly speaking an object that has 4x times more light hiting it will only appeear to be about 2x as bright. So as the visual brightness of an object increases it takes more and more change in scene illumiance to cause the same relative increase in brightness. If you store data in a linear way you end up in a sitiation where it takes ever larger value changes in the data to create a visual differences in the image or to put it another way the brightness of the image is much more sensitive to changes when the pixels are dark and much less sensitive to change when the pixels are light. The other option is to encode the data in a logrithmic way that more closely matches the way the eye responds to light. In this way a change in data values will have a similar change in visual brightness for both light and dark pixels. So if you take a pixel and change the value by 2x visually the pixel will appear 2x brighter as well. Encoding colors this way allows the limited number of possible values to be more efficently and evenly allocated.
  4. As an owner of a 9000PL, I can confirm that the SRW 9000PL does have slog/sgamut. It has the same sensor and therefore pretty much the same capabilities as the F35. It has some advantages like a better form factor for shouldering. It is much smaller, lighter and less power hungry compared to the F23 or F35 when paired with the SRW-1. It has 3g sdi out so you have more options for external recorders since you don't have to use dual link. Really the onlly downsides are you loose the 12bit and while being smaller than the F35 with the SRW-1 it is larger than the F35 without. There are some other nice things as weil, it can send sdi record trigger, activate tally's and auto fans without tape in the deck which is not as easliy acheived with the F35. While this ability was added specifically for use with external recorders, I do not know if the modern external recorders will detect those sdi trigger signals or not - never tested. The 9000PL does seem to have some improved processing going on internally as well. I previously owned a F35 and the 9000PL appears to have less noise and I feel am able to push the image further than I was able to with the F35, at least one stop (probably 2) with similar noise levels. This is purely subjective though, I don't have any tests that I can illustrate this since I no longer have the F35 but the specs do mention inproved processing and the camera has ISO800 gamma mode that the F35 doesn't have which I feel is related.
  5. Check out Olex services webpage, he services lenses in the Ukraine and specializes in Limo lenses including anamorphic. I believe he has diagrams for just about every lomo anamorphic lens ever made in his site.
  6. First of all the amount of data for 16 bit is 65535 values per channel regardless of whether it is raw or not. Technicallly 16 bit 4:4:4 has more data since it has 3 channels per pixel (RGB) where raw only has 1, making it 3x smaller. I order to grade raw footage it would be debayered into 16 bit 4:4:4 making it identical to uncompressed with everything else being equal. 1.) As stated above they contain the same number of data points. 2.) In a way yes, that is what you do when you grade footage. If your footage has a high dynamic range and you are displaying in on a with dynamic range you can grade the footage to try and fit all the dynamic range in. Camera sensors are designed to only capture what is in the visible spectrum. There really isn't anything in the image that you can't see like the LANSAT system you describe above. I believe the only spectrum most digital cameras can capture a little bit of that we cannot see is infra red.
  7. There is the Red 17-50mm, it is a little over your weight limit at 3.2 lbs but can be found for well under $3k.
  8. I don't know much about 2/3" cameras but I believe the Ursa Mini Pro has an B4 mount option. I have no experience with it and don't now much about it but the Mini can shoot at 3200 is if I am not mistaken.
  9. Probably possible with some medium/large format lenses. The focal distance of the lens has to be larger that the flange distance of the camera for a focal reduced to work which is why mirrorless cameras have them. They have a very short flange distance and can adapt to many more lenses.
  10. I would like to add to this that while these will work they are optical adapters like teleconverters and could degrade image quality of the lenses. I would recommend as others have stated as well to decide what lens mount you want to go with either by choosing lenses first, choosing a camera body first or both (Mirrorless Sony's for example can be full frame and adapated to a wide range of lens mounts). I wouldn't recommend having mixed lenses from lots of different mounts and trying to adapt them all individually.
  11. The D5600 has a Nikon F mount, which is one of the longest flange depth mounts out there. The flange depth is the distance from the mount to the sensor/film plane. Adapters are needed for cameras not only for allowing the lens to attach but also the put the lens the proper distance away from the sensor. If the lens is not the right distance then your focus marks will be way off and the lens may not focus to infinity or reach the min focus distance marked on the lens. I am not sure what mount all of those lenses have but the Canon FD and maybe the others if they are not Nikon mount will most likely have a flange focal distance that is much less than the F mount on the D5600 and will not focus to infinity. Not all lenses can be adapted to any camera system. The GH4 has a very short flange focal distance and can be adapted to many more lenses than a Nikon as a result but as noted above there is no speedbooster in existance that can give you full frame from a M43 camera.
  12. I purchased a Cinematics 28-70mm nikon in PL mount a while back. I liked the lens and seemed to be pretty well made and sturdy. It contacted the PL mount the F35 I was using it on so I was not able to ever test it and ended up returning it.
  13. The thing is you have to face facts. While film may be beautiful it is also, costly, wasteful and hazardous. Technology is improving all the time and soon enough it will surpass film and in the areas where it does not the audience won't care as they are growing up in a digital world anyway. Film is amazing and I hope there is always a place for it to be capured and projected but in Mass film as presentation is dead and is probably never coming back.
  14. As far as digital cinema goes, dolby cinema is my preference by far. Deep blacks and bright whites. The only issue I have with is at my local theater they have red lighting which is close enough to spill on the screen and is noticable in really dark scenes. I am not sure if that is common or not.
  15. I am not in the market for a PC so I am not up to speed on the latest but what I would recommend is a large SSD 200GB or more for running the OS. The top of the line or runner up Nvidia graphics card from last year, not current as it will be half the price. 16GB of ram is probably enough but I would go with 32GB just in case. An I7 processor and a raid of 7200 rp disc drives, at least 4. These can be added internally using a software raid. Generally what I do is build a custom PC that would have been top of the line a year or two ago. Normally spending around $1500 or so.
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