dhessel

I can see both sides of the argument here, I definitely don't agree with many out there that film is so much better visually than digital and that the gap between them is closing rapidly. However this is like saying now that you can paint a picture in photoshop/painter with a wacom tablet there is no reason to use real paint anymore. Paint is messy, expensive and takes time to clean up. Digital is quicker, you have far more freedom and options for manipulating it, etc... Working with film is an art form just like working with paint and I personally feel it is a real loss anytime any art form is lost. No matter what some say about why film is better than digital, I suspect deep down it is more about a love and respect of the art of film rather than love of the film itself.

I have fixed this before in AE using a slightly different and probably more correct way. Bring in the footage and put it in a comp and un-squeeze as you normally would by scaling, pixel aspect ratio, etc... Apply a transform effect to the footage and adjust the rotate parameter until the un-squeeze is correct. This method rotates the image prior to the un-squeeze skewing the footage. Rotate the layer opposite of the effect rotation by an equal magnitude to re-level it. Punch in to hide the skewed edges. 

However the resulting footage will have slanted bokeh and flares unless you don't counter rotate the footage back to its original orientation. This would most likely cause all of the shots to be off level but may be useful for shallow dof/flare filled shots...

Why not make a fake label for the whiskey and use similar looking alternative to the famous medicine you speak of, if it is what I am inferring it is. That way you should have nothing to worry about.

http://www.ebay.com/itm/VERY-RARE-Iscomorphot-8-1-5X-Isco-Gottingen-Anamorphic-lens-Kowa-Sankor-Bell-/261689938140?pt=Camera_Lenses&hash=item3cedef90dc

This is the least expensive one on ebay, there are a few more as well.

Just when it looked like the DREADFULLY  ANTIQUATED 24fps standard was on the verge of seeing it's loooooong overdue replacement, "The Hobbit" single handedly derailed the whole HFR movement. It's a terrible tragedy that this ONE turd of a movie was used to judge the efficacy of the emerging new standard.

While I don't necessarily disagree with you opinion on this matter, I think it should be pointed out that one of the biggest issues with HFR on this movie had nothing to do with the quality of the movie itself but rather with the fact that viewers were physically uncomfortable and nauseated when watching in theaters...  

Imagine an infinite horizontal square section hallway, you are in the center of it with a camera watching down the hallway. The lines will converge on a point located at the same hight you are observing and located at an infinite point. You can use what ever focal length you want, they will always converge on the same point,and they will always have the same angle. The only thing that changes it the spatial relationship between points with different distances from the observer along the viewing axis.

 

or just watch this image:

Zooming in, or cropping in would have the same effect.

From working in computer graphics for the last 14 years I can tell you that this is absolutely correct. With a pinhole camera changing the focal length is identical to cropping in on an image. Changing the focal length doesn't alter perspective only moving the camera can do that. In real life they are not necessarily identical due to different depth of field characteristics and lens distortion, etc... but for all practical purposes zooming and cropping are identical - hence digital zoom.

I find this to be a common misconception about speed boosters to, all they do is brighten the image and "un-crop" the image to a larger image but do not alter the perspective or DOF in anyway. Focal length only affects depth of field, the FOV is the result of the relation ship between the focal length and imaging size but the image itself is identical for all sensor sizes the only difference is how much of the image you see. Perspective is purely defined by the physical location of the camera.

Also watch out for the blue channel clipping this camera has with LED lights, many have complained about it while recording concerts/live events. There are workarounds like using a WB of 5500 or higher, if I recall correctly. There should be posts here or at dvxuser that detail how to avoid the issue.

http://www.dvxuser.com/V6/showthread.php?327633-A7S-colored-highlight-peaking&highlight=highlight+clipping

Rather than bog this thread down with more opinions regarding Sony's color science, since you seem to be possibly experimenting with Resolve, it may make sense for you to explore the new Color Match feature.  One of many Resolve Color Match demo videos on the Internet:

 

 

The smallest and least expensive compatible color targets are these two:

 

http://www.amazon.com/X-Rite-MSCCPP-ColorChecker-Passport/dp/B002NU5UW8

 

http://store.smpte.org/product_p/dlab-smpte-pos.htm

 

Importantly, I'm not suggesting that you have to shoot a chart for every one of your setups. 

 

However, this very useful tool will quickly get you into the ballpark and you will be able to see what it is doing to bring your images into alignment.

 

And once you settle on a particular profile, you can use this tool to create LUTs that can be used in other software platforms.

 

Additional related reading can be found here:

 

http://provideocoalition.com/aadams/story/what-good-is-a-macbeth-colorchecker-chart

 

HTH.  Good luck.

Since I keep seeing posts claiming that the colors are just off with the A7s, in the video posted here along with other suggestions on how to get nice colors with the A7s I will reiterate this crucial bit of information. If you are shooting s-log2 with s-gamut you MUST convert from s-gamut to sRGB or Rec709 colorspace, if you do not the colors will be wrong you cannot simply grade s-gamut footage. Other than leaning towards blue, which is common for Sony, in the footage I have worked with I have seen nothing wrong with the colors coming from this camera.

Yes the secret to using s-log2 at least with default PP7 is not the gamma curve it is the s-gamut. You must convert the s-gamut colorspace to sRGB if you want to get reliable colors. Sure a lot of the time you can just add contrast and get something that is close but it is just a hack with some nasty surprises. This is why so many have trouble with s-log2 they just bring it and do some curve adjustments and add saturation which is totally wrong. I find that with default settings s-log2 when converted properly almost has too much saturation, there is no way I would ever increase the saturation in camera as there is plenty there.

This conversion can be done with a lut or with a matrix transform as posted previously. The problem with luts as I understand it is that the shot must be exposed and white balanced properly to get a reliable conversion with a 3dlut. The Impulz luts are calibrated assuming you have exposed normally. If you shot 2 stops over to help with noise in the shadows these luts will no longer convert properly. Using a 1D lut for s-log conversion and a color matrix for s-gamut to sRGB doesn't appear to have this issue and is my preferred method at this point.

I have a sample workflow with adobe products that I posted before showing how to do this. I have recently found that my 1D lut is a little off of the formula supplied by sony. It has a little less contrast in the highlights which I actually prefer but I may have another go at it to see if I can fix that. It would by nice if there was a way to control color using expressions in Adobe. Any know if that is possible?

Here is the post I was talking about.

>

Looking for one of these with or with out the taking lens. Thanks in advance.

M42 will not work on a Nikon mount without loosing infinity focus. You would need to pick up a adapter or speed booster for EF or M42. The RJ speed booster is quite good if you don't want to spend $650 for the metabones one. RJ will take best offers for $95 for his. Being able to use m42 lenses is a big plus since there are a ton of cheap m42 lenses out there.

I don't have a huge amount of experience with different lenses but my favorite few are...

1, 50mm Lomo Squarefront Anamorphic Lens

2. Lomo Foton 37-140mm

3. Helios 40.

The helios has the most character of any of my lenses, it is most usable when stopped down a bit but wide open has very stark and interesting colors, soft swirly bokeh, and a very  dream like quality. Stopped down it retains a lot of its character but is almost like a different lens, colors and contrast change quite a bit. Since it does have swirly bokeh I tend to use it more for stills than video though.

We shot some footage using a ninja blade and all the video came out 3:5 ratio when using M mode. We also had stuttering if recording internally at the same time. Shooting in movie mode has been good so far. Anyone else seeing this?

There is no mention in the OP's post about image quality he asks what camera setup would be best. Since I have no idea what he intends to shoot I gave general strengths and weaknesses for both in an attempt to give him some useful feedback.

No the night shots I have seen look rather odd to me and I am not a fan of them either. I am not saying that this camera is for shooting in the dark, I don't need night vision. I am saying that it can be used to shooting indoors or on city streets at night without the need to be wide open all the time. I have the feeling you are a someone who has seen all the hey the A7s can see in the dark videos thinking how ridiculous they are and never thought how that super sensitivity and clean images at high ISO's can be extremely useful in more practical situations.

 I will take the king and queen debate as sarcasm and only say that in English queen can have negative connotations depending on how it is used at least in reference to a camera. I am avoiding those since I think the A7s is an awesome little camera.

Difficult to say without knowing what you are shooting.

The BMPC has much better codecs, 10 bit prores and Raw compared to the 8bit AVC-S from the sony even with a shogun it will remain 8bit since it is 8bit out the HDMI. Both have log modes for preserving dynamic range were the A7s on paper seems to have the advantage I have not seen any comparison between the 2 so I cannot say for sure. Surprisingly the 8bit slog seems to hold up very well when graded but the BM has the advantage there.

 The A7s is a more flexible camera you can choose to shoot full frame or APS-C and the E-mount makes it possible to use just about any type of lens. You can shoot 60P or 120P with the A7s but are limited to 30P on the BMPC. The A7s does have bad rolling shutter in FF mode but it is much improved in APS-C mode where the BMPC has no rolling shutter at all.

The A7s is the low light king at the moment and there is no better camera out there for shooting in low light. While you may not need night vision the sensitivity makes it possible to shoot in dim light without being wide open. The BMPC however is not low light camera and must be lit properly.

Is you are using slog with sgamut you must convert sgamut to srgb if you don't the colors will always have issues. This can be done with a lut but I have not found many that seem to handle it very well.

You are getting vignetting because you are using full frame glass on a full frame sensor with a speed booster. You will need to shoot in asp-c mode to prevent this.

I can understand that completely. I am the same way, and I fact I did test it myself as well in a script I wrote on Windows. If I had the app I would post it but I am on Windows so never downloaded it.

The reason why there are no responses and the links are down is that the whole concept of 10bit from down scaling to HD is flawed, it doesn't work the way it was originally theorized that it would. This app won't give you anything more than just scaling down in your NLE. The NLE is probably better since it has more advanced scaling algorithms anyway. I don't have it so I can't upload it but there is nothing to gain by using it anyway. 

Check out the previous posts in here if you want to know why.

That is right It doesn't mean that it is clipping, it could be but doesn't have to be. The value would be over 100 IRE, if it is between 100 IRE and 108 IRE it won't clip in the file, if it is over 108 IRE then you will see clipping in the file. That is my understanding but I am fairly new to the whole concept of video levels myself.

It varies depending on picture profiles but camera can record 0-255, 255 would be 108 IRE if I am not mistaken.

I could be wrong but I believe the IRE scale is for video levels. Video levels translate to 16-235 rather than 0-255 for full 8bit. Therefore it is possible to record above IRE 100 without clipping. 

Ok I believe I have only seen that with nuke. But wanted to check.

Not familiar with that file format, can it be used in after effects and resolve? Also I was originally going to go from s-gamut to xyz and to rgb from there but it appears that the channel mixer has a maximum value of 200 which made it problematic for most of the xyz to rgb matrix. Also I felt a direct convert would be simpler for most purposes.

Thank you for all of that information. I believe it was some of your posts on the foundry forums that were a starting point for all this. I understand that the s-gamut offers a wider range of colors but what is somewhat unclear is what benefit it would have for grading compared to using a different color mode. I have not worked much with files outside the usual srgb colorspace.

Thank you for confirming what I suspected about a 3D lut not being as accurate as using a matrix, I didn't want to make that claim until I looked into it more. I am not real familiar with the all the options for 3D luts but was pretty sure I had not heard of any that have more than 64 samples per channel. That would result in quite a bit of interpolating compared to a matrix which has no interpolation and is lossless. The 1D lut I generated has 1024 samples so it has plenty of data for an 8bit source. 

I have considered combining them but haven't yet since I am new to luts and wanted to keep the gamma correction separate from the color at this stage. If this looks worthwhile then that would be the next logical step.

Not sure what benifit s-gamut may have but I do feel the other modes like pro and cinema are somewhat looks and would just likento have the option of using s-gamut. Sony put that combo on their high end cameras for a reason I am sure.