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  • 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 :)

LIST of Lens Sets that cover 6k

Matt Ryan said:
The Epics sensor in 5K FF is slightly larger than s35, which are what cinema lenses are designed to cover. When you put a lens on a larger sensor, it can't cover it so it vignettes or portholes as some will call it. It's just because the lens does not have a large enough image circle to cover the sensor completely. When you window into a s35 frame size on the Epic in 5K (5K 2:1, 5K WS, & 5KHD), the lenses cover fine because the sensor is only capturing from the s35 area of the sensor. Does that make sense? If they were using stills full frame lenses they wouldn't have an issue because true FF is larger than the Epic in 5K FF.
Click to expand...

I understand all of this, I was actually referring to this post in particular in saying that while it technically covers the whole sensor, there's issues with it: http://www.reduser.net/forum/showth...hat-cover-6k&p=1100035&viewfull=1#post1100035
 
James_Mills said:
I understand all of this, I was actually referring to this post in particular in saying that while it technically covers the whole sensor, there's issues with it: http://www.reduser.net/forum/showth...hat-cover-6k&p=1100035&viewfull=1#post1100035
Click to expand...

Yeah, that just means that they are s35 lenses with a bit more coverage than typical s35 (the back element has a wider image circle), but it's not good glass and wasn't meant to be used on a larger sensor. So theoretically it covers the larger size, but the worst part of the glass will be visible in the corners and probably be distorted to some degree. Lens makers focus on the s35 area and making it as sharp and clean as possible and don't focus on the areas outside of the s35 sensor. But they still won't cover a true FF sensor. Hope that helps.
 
Matt Ryan said:
Yeah, that just means that they are s35 lenses with a bit more coverage than typical s35 (the back element has a wider image circle), but it's not good glass and wasn't meant to be used on a larger sensor. So theoretically it covers the larger size, but the worst part of the glass will be visible in the corners and probably be distorted to some degree. Lens makers focus on the s35 area and making it as sharp and clean as possible and don't focus on the areas outside of the s35 sensor. But they still won't cover a true FF sensor. Hope that helps.
Click to expand...

Makes perfect sense, thanks again.
 
updated, anything I'm missing?
 
Anyone test the Lecia Summilux C's?
 
James_Mills said:
I understand all of this, I was actually referring to this post in particular in saying that while it technically covers the whole sensor, there's issues with it: http://www.reduser.net/forum/showth...hat-cover-6k&p=1100035&viewfull=1#post1100035
Click to expand...

If I could clarify:

When a lens manufacturer produces a lens, they have certain performance criteria they strive to attain within a chosen format size. This criteria can include sharpness, CA, distortion, even field illumination, and many other attributes. Cine lenses, and expensive high quality photography lenses, have much stricter criteria from lens to lens and overall... with cinema lenses typically being very strict.

This does not mean the lens's image circle is no larger than the intended format size. Depending on lens design an image circle can be barely larger or much larger than the target format, and that area of 'unintended' circle can vary in performance. Sometimes the area of the image circle just outside the intended format size is close to that within, sometimes the quality falls quite rapidly as you leave the intended area. Again, it depends on the lens design.

Typically, wide angle lenses have smaller image circles, ending just outside their intended format. Longer focal lengths can typically have much larger image circles. As an example, the Cooke Mini-S4 lens lengths 75mm and 100mm cover FF with their image circle... but the part of that image circle which was intended to be seen was only the middle 33.54mm. Outside of that portion of the image circle, does not guarantee the quality of aforementioned criteria. So we will see the edge to edge sharpness (which usually falls on edges even in intended areas) will be much worse in the unintended area, as well as CA, distortion and vignetting. Again, this varies by lens design and of course that means focal lengths.

So there you have it. What I meant was that there are many people who will take a lens and slap it on a camera... if the lenses entire image circle covers the sensor, then they claim it's good to go. But they may have not looked carefully.... They may not have realized that the unintended portion of the image circle, the part the lens manufacturers thought would never be seen thus did not concern themselves with, might be seen. So what we see are what the manufacturers might consider unacceptable CA, sharpness or vignetting in the corners.

There is a great test a member of the Australian Cinematographers Society just posted that compares the new FF CP.2 SS's, the new Canon's, and Zeiss UP's. They found, at Epic 5k, the corner of the wide-open 24mm UP to be much worse than the new Canon and CP.2 equivalent 25mm's.... Well, I'm not super surprised. Although UP's are amazing, if not one of the best lens sets known to cinema, they were designed for roughly the sensor size of 4k on Epic. The people at Zeiss concerned themselves with designing a lens that was not only mechanically, but optically great at the S35mm frame. They did not care if the lens image significantly got worse off the sensor. That was not the goal. However, here comes Epic 5k, who's sensor is considerably larger. Now when you compare a UP on 5k, you are seeing into the area of the image circle the lens designers never thought you'd see. As mentioned, wider angle lenses tend to have smaller image circles and the quality of the circle degrades much faster. No wonder the 24mm UP at 5k was no match to the FF ones. They did find, however, in the same test, the longer UP lengths, like 50 and 85 were relatively better or equal in sharpness in comparison to the Canon and CP.2's, even in the 5k area. That is less of a surprise since the image circles tend to get larger the longer the lens is, and hence the fall off of quality is typically slower. Again this can vary.

See this image:
RedScarletXCropFactors1-616x324.jpg


Assuming this reference image I grabbed is correct, you can see the difference in FoV between 4K and 5k. You can also see how the lens they used for this sample image ALSO shows signs of quality drop in the corners of this lens. The vignetting is MUCH more severe in the 5k area. Goes to show that this is an issue with outside intended image circle with cinema lenses and even within the intended image circle of photography lenses, since photography lenses do not concern themselves with the same criteria as cinema, considering they are for different uses. Look at this website and find your favorite photography lenses wide open. You'll see they typically have unfavorable vignetting even at APS-C 'crop'. You won't find cinema lenses that typically show that much uneven field illumination... even wide open. Of course some are better than others.

So that is what I meant. I'm all for cinema lenses. I love them, and I mainly work in the cinema world, so they are the appropriate lenses for me. Thus I like it when they cover, because I love to use 5k and I love to use cinema lenses... but am lamented when I examine some makes and models to find the unintended area of the circle is quite poor on 5K. However, as mentioned, this varies from lens to lens, longer focal lengths tend to do much better, and there are some lenses like Cooke Mini-S4's, the some new Angie Zooms, Fujinon Cabrio, CP.2's, Canon's and more which are designed to meet Epic 5k frame size and some larger.

So those Epic 5K friendly models have the manufacturer standing behind their quality at the Red Epic 5k sensor size. Now here comes 6k... and although we don't know how exactly big it is, we know it's slightly bigger than 5k.

I'm just saying is there any chart or quantifying quality of which we can rate lenses that cover, but weren't made to cover?

It's a tricky proposition and something that does not just plague cinema lenses (which are often designed for no larger than S35) Many photography lenses, even though they are supposed to cover FF, lack the standards of cinema lenses and thus may also have uneven field illumination, sharpness, CA, etc... especially wide open.

I guess this is simply a call to those who are exacting enough, to simply look carefully at their lenses and their recording format. If you can forgive the loss of quality in the corners, go ahead, but my warning was to not simply listen to those who say a lens covers 5K... because simply having the image circle cover does not give an indication of the quality within that circle.
 
Ryan Patrick O'Hara said:
If I could clarify:
See this image:
RedScarletXCropFactors1-616x324.jpg


Assuming this reference image I grabbed is correct, you can see the difference in FoV between 4K and 5k. You can also see how the lens they used for this sample image ALSO shows signs of quality drop in the corners of this lens. The vignetting is MUCH more severe in the 5k area. Goes to show that this is an issue with outside intended image circle with cinema lenses and even within the intended image circle of photography lenses, since photography lenses do not concern themselves with the same criteria as cinema, considering they are for different uses. Look at this website and find your favorite photography lenses wide open. You'll see they typically have unfavorable vignetting even at APS-C 'crop'. You won't find cinema lenses that typically show that much uneven field illumination... even wide open. Of course some are better than others.
Click to expand...

That image above is an "impossilens" shot. Meaning it's a panorama. That vignette was added in post. It's only designed to show the effect of the different crop factors/recording formats of the MX sensor.

A safe bet with lenses that cover our future 6K sensor will be to go towards FF35 stills glass and newer FF35 oriented cinema glass. As Ryan has noted lenses that aren't designed for such a large frame, yet may still cover may suffer from vignetting and strange optical performance. Some lenses "porthole" and porthole even worse at smaller apertures. It's just do to the fact that the lens just wasn't designed for that format. Currently MX 5K and Dragon 6K will land in the sweeter spot of FF35 glass and provide very nice image. Some FF35 vignettes on full frame (most actually to some degree) but usually stopped down between 2 and 3 stops it clears up.

Remember also how Red's "full" and "HD" framing come into play.

Here's a much more accurate version of the above graphic with HD formats included:
RedMXFormatCropFactors.jpg
 
Phil Holland said:
That image above is an "impossilens" shot. Meaning it's a panorama. That vignette was added in post. It's only designed to show the effect of the different crop factors/recording formats of the MX sensor.

A safe bet with lenses that cover our future 6K sensor will be to go towards FF35 stills glass and newer FF35 oriented cinema glass. As Ryan has noted lenses that aren't designed for such a large frame, yet may still cover may suffer from vignetting and strange optical performance. Some lenses "porthole" and porthole even worse at smaller apertures. It's just do to the fact that the lens just wasn't designed for that format. Currently MX 5K and Dragon 6K will land in the sweeter spot of FF35 glass and provide very nice image. Some FF35 vignettes on full frame (most actually to some degree) but usually stopped down between 2 and 3 stops it clears up.

Remember also how Red's "full" and "HD" framing come into play.

Here's a much more accurate version of the above graphic with HD formats included:
RedMXFormatCropFactors.jpg
Click to expand...


Agreed.... but again, the sweet spot of stills glass is often times not as sweet, but will cover those unintended corners better. It's frustrating at times. They (stills) have much lower standards especially wide-open and are very fond of tradeoffs. I can't stress that enough. For instance, almost all FF glass will show what is unacceptable uneven field illumination when wide open. This goes away two stops down for the most part, but it's a good example of trading speed for quality, something top-shelf s35mm cine lenses don't typically do, but then again they are usually much larger lenses for a reason. At FF it's apparent, but even at APS-C, on wider angles, you'll see a stop, stop and a half at corners from center. Not major, but worth noting. Often it's hard to see because is so very gradual from the center.

For now, I've been amassing glass that is 5k friendly, as said by manufacturer, knowing that 6k is probably not terribly larger. The area of unintended image circle that will be seen from 5k Epic to 6k dragon will be nothing like the jump from 4k MX to 5K MX. That was pretty big. Right now I'm going to stick with my Mini-S4's, which are advertised to be over 5k ready (33.54) and a Fujinon Cabrio (5k advertised but not sure the exact intended image circle).

Call me stubborn, but I'm not giving up my lenses for CP.2's just yet. My lenses will likely squeak by at 6k hopefully without too much quality loss on the extreme corners, as I hear 6k is not much bigger than 5k now, and these lenses are advertised as Epic 5k and more. For now, 5k is wonderful, and 6k sounds to be pushing limits. I might not follow after that, if Red goes that way. Since Red is the ONLY professional camera with a considerable S35mm+ image (except Phantom 65), I'm quite fine with this stance for now. It's a preference thing, and if I wanted to shoot FF, I'd be shooting 5D's. I'm for more resolution, more DR, more everything, but I'm one of the few DP's who likes shooting at a T/4. I don't want to be Mr. Shallow DoF, so I see FF sensors as making my job more difficult. I'll likely be using longer lenses to get the FoV I typically desire, thus will need to close the lens down to get the DoF I like. I don't want to shoot a T/8 to get what I normally get at T/4 or whatever that works out to.

Unless there are more advantages than simply getting EVEN MORE resolution than I already need, I see no reason to ditch the glass I like for anything else.
 
I'm certainly hoping people keep their quality S35 lenses. Mainly due to the fact that Dragon's 5K will be slightly larger than today's MX 4K. In fact, because of that I think we'll see some new life out of those lenses.

I think with this new sensor we're going to have the ability to really choose which "format" we want to shoot with.
 
Phil Holland said:
I'm certainly hoping people keep their quality S35 lenses. Mainly due to the fact that Dragon's 5K will be slightly larger than today's MX 4K. n fact, because of that I think we'll see some new life out of those lenses.

I think with this new sensor we're going to have the ability to really choose which "format" we want to shoot with.
Click to expand...

Agreed, even 16mm lenses will render out at 3K now. How awesome is THAT?!?! And with tighter pixels and higher DR, this 3K should look even BETTER than current 3K.
 
And 16mm lenses are dirty cheep right now...

Nick Morrison said:
Agreed, even 16mm lenses will render out at 3K now. How awesome is THAT?!?! And with tighter pixels and higher DR, this 3K should look even BETTER than current 3K.
Click to expand...
 
A 12mm Zeiss 16mm Mark Ii doesn't cover 3K completely, and the 9.5 even less. From 16mm and beyond they are OK.
 
Anyone know if the Leica Summilux C Primes will cover 6k or currently cover 5k?

So are we saying if a lens covers 5k now, it should do 6k wide screen without issue?
 
Uli Plank said:
A 12mm Zeiss 16mm Mark Ii doesn't cover 3K completely, and the 9.5 even less. From 16mm and beyond they are OK.
Click to expand...

Uli we know, we mean 3K on DRAGON! But if any S16mm lens covers 3K now, it will probably cover 4K on Dragon! (Its my understanding that all present coverage goes "up a K" on Dragon. So current 2K becomes 3K, current 3K becomes 4K, current 4K becomes 5K, and 5K becomes 6K with a slightly larger image circle at this last setting).
 
Doing my research on ultra wides that will cover 6K and it seems that the options are limited.

My interest is in an appropriate lens inside a water housing that will give me an ultra wide - as wide as possible without any fisheye effect.

At 5K, I currently use a Tokina 11-16mm which does a great job, as it:
- pretty much covers 5K (as discussed in many threads at 11mm I have a hint of vignetting at 5KFF, but are usually shooting WS or cropping slightly in post so no problem)
and
- with the flat front glass element I can easily filter the lens with screw on NDs (essential in a water housing)

I've been hunting around but can't find anything appropriate.
Something like a Zeiss 15mm would be great but a little wider would be better (and I can just use the Tokina at 14-15mm and it should cover the Dragon sensor at 6K).

Any lenses for consideration?
- ultra, ultra wide (about 12mm)
-coverage of Dragon's 6K

I might be dreaming ;)
thanks
wes
 
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