Welcome to our community

Be a part of something great, join today!

Register Log in
  • Hey all, just changed over the backend after 15 years I figured time to give it a bit of an update, its probably gonna be a bit weird for most of you and i am sure there is a few bugs to work out but it should kinda work the same as before... hopefully :)

Let's talk sensor...

Status
Not open for further replies.
In the printing, graphic design and photography industries, cropping refers to removing unwanted areas from a photographic or illustrated image. One of the most basic photo manipulation processes, it is performed in order to remove an unwanted subject or irrelevant detail from a photo.
Click to expand...

removing artifacts from the image and resizing the image, it doesn't have to be the lower half or the left half of the image u can remove pixels and manipulate pixels into smaller sizes and it would be cropping.
 
u can remove some of the bit depth of the image and re-size it into a smaller image, and it would be considered cropping also.
 
u can mask small artifacts inside the image it doesn't have to be a big block of the image.
 
Ive never heard either of those refered to as croping. Always either down-sampling or re-sampling or down-resing. Eitier way we are arguing terminology. The one technique results in a crop factor, which the red doesnt do except in 2k or 3k modes, and the other doesn't.

more to the topic;

I don't know if it would be possible to put a 4:3 'four perf full frame' sensor in the Red, looking at my sensor you'd need a new sensor-holder-thing. Id imagine epic would have something similar, but who am i to say. Its red digital cinema, i'm sure they could replace it if they felt like it.
 
Ive never heard either of those refered to as croping
Click to expand...

other than the crop factor and the down-sampling, the others or done manually thought the whole image, pixel by pixel, it's hard work and takes time, that's dedication to make the best possible quality and not something otherwise "workable", it's called art.
 
Anyway, Amrrahmy, what is Your Red One's serial number again? Have You EVER even downloaded any 4K r3d RAW file and play with it in Red Cine, or Red Alert?

Now to be fair - I do not have Red One myself. But I am not arguing with the ones that have it about the issues related to this camera. And I did downloaded tons of r3d RAW files in all sorts of resolutions and work with them in both Red Cine and Red Alert...
 
yes, i downloaded tons of samples. and seen how good or bad the image can be.
 
David Mullen has displayed commendable patience here. :pinch:

Brook, excellent thread...I had my ghetto resolution diagram in another thread but have no experience with film, so I had no clue what the actual sensor sizes were compared to film and how the FOV would be effected, or anything for that matter and was hoping someone would clear as this up for the n00bs like me. I think it's interesting no one wearing a RED cap has chimed in yet.
 
Wow. Cropping. Who thought that would be such a difficult concept to grasp?
 
David Mullen ASC said:
I think we are running into a language barrier here because my definition of "cropping" and "workable" are different than yours. But here is the Wikipedia definition of cropping:

http://en.wikipedia.org/wiki/Cropping_(image)

And my definition of "workable" is "something that works". And my 4K RGB files seem to be working just fine.
Click to expand...

I feel sorry for you, David. But it is actually quite funny reading your patient and measured explanations to this guy :)
 
This thread is strange, so I'll add some more ;)
If a 4K image will allow downsampling to 3K and up again to 4K without any visible or significant measurable loss in resolution, the "4K is really 3Kish" statement is true.
But a bayer matrix is not that simple. If you shoot a near monochrome subject you record some real info in ALL pixels. Then you loose by downsampling. If you shoot a pure red image you will not loose much. The point is the bayerchips is hitting color resolution harder than monochrome resolution. The claim that 4K RED is more like 3K is oversimplified because it depends what you are shooting. I find that using a RGB foundation is not a good way to approach these kind of discussions in this thread even if the chip is RGB.
Someone please do what I propose with a RED in real life, I haven't one yet but have done it with medium format stills cameras, and I find my statement to hold tight there. The priciple shouldn't be very different from RED to a high quality still camera, but I can't do this myself yet. So downsampling the 5K EPIC to 4K will loose you monochrome info, but not color info as I see it.
MHO.
 
Good post, Brook. I agree with you about the sensor size and aspect ratio. 4:3 is also good for one other thing we have not discussed... IMAX! :)

If we are talking about numbers like 5,120 x 3,840, you have to start to worry about how many pixels can be crammed onto a chip that is relatively small compared to a 35mm still frame. Even the top-of-the-line Nikon D3 is nowhere close to this resolution, and its sensor is much, much larger than Red One's.
 
Tom said:
Good post, Brook. I agree with you about the sensor size and aspect ratio. 4:3 is also good for one other thing we have not discussed... IMAX! :)

If we are talking about numbers like 5,120 x 3,840, you have to start to worry about how many pixels can be crammed onto a chip that is relatively small compared to a 35mm still frame. Even the top-of-the-line Nikon D3 is nowhere close to this resolution, and its sensor is much, much larger than Red One's.
Click to expand...

IMAX (15/70)
* camera aperture: 70.41mm (2.772″) by 52.63mm (2.072″)
* aspect ratio: 1.34:1

Why do you want 4:3 for Imax? To use Anamorphic lenses?

Canon has already managed to cram 5,616 x 3,744px into the Mark III so I think in 2 years perhaps the EPIC can easily be 6,000+px wide at S35mm, don't you?
 
PerfectOptics said:
With the lens market what it is, i'll bet if someone designed a set of 1.33 stretch anamorphic primes that were of excellent quality and aperture, people would be happy using them as an anamorphic solution to a 16:9 red.

2:1 anamorphics were designed because all cameras at the time used 4:3 frame sizes, not nessisarily because it was the perfect choice. Today nearly all cameras are 16:9, why not make a new set of anamorphic as appropriate.
Click to expand...

Do you suggest that 16:9 have a anamorphic lens that stretches to wider look? I would like to see how that would look.:turned:
 
RobinBalas said:
This thread is strange, so I'll add some more ;)
If a 4K image will allow downsampling to 3K and up again to 4K without any visible or significant measurable loss in resolution, the "4K is really 3Kish" statement is true.
But a bayer matrix is not that simple. If you shoot a near monochrome subject you record some real info in ALL pixels. Then you loose by downsampling. If you shoot a pure red image you will not loose much. The point is the bayerchips is hitting color resolution harder than monochrome resolution. The claim that 4K RED is more like 3K is oversimplified because it depends what you are shooting. I find that using a RGB foundation is not a good way to approach these kind of discussions in this thread even if the chip is RGB.
MHO.
Click to expand...

But you don't downsample to 3K and go up again to 4K, you convert 4K RAW Bayer to 4K RGB, and the resulting measurable resolution is 3K-ish. But there is no conversion to 3K involved in the process, no downsampling and uprezzing -- it's an algorithm that has to take the Bayer pattern and reconstruct full color from it.

Otherwise, you'd be doing it the "dumb" way -- converting 1:1 the 50% green photosites in a 4K RAW Bayer sensor to 2K and the 25% blue and red photosites to 1K, and then uprezzing 2K to 4K for the green channel and 1K to 4K for the red and blue channels.

Also, 35mm film is not "full resolution" in all color layers either. The red record tends to be soft-focus and the blue record tends to be grainier. In fact, some people do this post trick of throwing the red channel info out of focus slightly to give a digital image more of a "film look".

My point is that the notion that a 1:1 pixel for pixel process is ever achievable with a Bayer design is nonsensical -- it has to go through a conversion, a transformation, process to recreate full color. There are never going to be an equal number of red, green, and blue filtered photosites, plus that would be considered a "dumb" or simplistic conversion algorithm that does not take advantage of the fact that there is some color info in each photosite for the other two colors.
 
Status
Not open for further replies.
Back
Top