Red lenses

Could cheap lenses cause vignetting with Red?

Could cheap lenses cause vignetting with Red?

Heres one for our lens experts Greg, Gibby Proteus etc

Over at DV info on the thread: cineform and SI wins award. This comment was made in response to a query.

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The vignetting is due to the sensor being larger than the image through of my (yes cheap) 16mm zoom, the super-16 lens did not do that.

David Newman
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Interesting don't you think?

Michael
 
I'm not surprised David experienced that range of image quality between a cheap 16mm lens and a better S16 lens. Besides being 16mm, it was a zoom, and probably an old zoom. He didn't mention whether the S16 lens was a zoom or prime, but either way he would get a better image than the old 16mm zoom.

With some exceptions, you get what you pay for in glass. Simple as that! That's not to say that some glass isn't overpriced and probably overrated. Prejudices and biases are widespread among cinematographers, videographers, and photographers. Lab testing of lenses can produce data to satisfy the most demanding left-brainers, but practical application and testing on location is what professional shooters should use to form an educated opinion on any particular lens. Beyond lab tests, and obvious lens defects, judging lens quality is necessarily subjective, and each professional shooter has their own desires, project needs, and experience.

If the S16 lens David used didn't vignette, then the blame for the vignetting probably was probably the smaller coverage area of the 16mm zoom and it's poor glass.

To my knowledge, RED doesn't recommend the use of 16mm lenses on RED One - S16 yes, 16mm no. I think the X factor in the "you get what you pay for" scenario with lenses is adapting 35mm photography lenses for use with RED. There are some real good 35mm photography lenses out there, many of which have been noted on this thread. Many of them are quite a bit more affordable than S35 lenses, but may provide images that are quite similar, in the hands of experienced shooters. Only field testing with those lenses on RED will answer that.

RED definitely has a big sensor, and I'd suggest users follow the lens formats recommended by RED for best results (no regular16mm). I'm not an expert on the SI camera, but I'd hazard a guess that SI never recommended the use of "cheap 16mm zooms" on their product.

All this said, when I get my RED camera, I’m going to mount every type and size of lens I can, just to personally test the parameters of image degradation. I suspect that for certain project production values and “looks”, many lenses that people aren’t thinking of, and that aren’t on the RED-recommended list, will generate interesting and effective images. I can’t tell you how many times in my career I’ve heard other shooters badmouth a particular lens, but when I’ve field tested it, I found certain qualities and applications for it I liked and ended up using it for certain projects.

It’s when RED gets into the hands of open-minded, but highly-experienced shooters that aren’t afraid to experiment, and aren’t tradition-bound, that the true boundaries and potential of RED imaging will be defined…

Gibby
RED #8
www.cut4.tv
www.4umat.com
 
If you mount a less that's intended for a smaller format on a larger format you may experience vignetting, no matter whether the lens is cheap or expensive. In the case of a zoom, the vignetting will occur most at the widest focal lengths.
 
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WOW evinsky such a great link. Just briefly read through (for the time being) but......I think this little bit is interesting. Please anyone feel free if you feel i am posting useless info, pm and tell me or do so by posting. I am learning a huge amount from you guys so i only add these little bits to try and extract more info from the experienced one's. In doing so i hope i am not going OTT. With Red i face a huge challange and i know i must learn a lot more just to evaluate the purchase in many ways.

This was from the link ,it was comparing the two zoom still lenses made by cannon and nikkon.
[FONT=Courier New, Courier, mono]I suspected that defining 'better' in this instance would be slippery: even the Leica 21-35mm is not equally rectilinear at all focal lengths. Both these lenses have differing distortion characteristics throughout their range, so your verdict will likely be weighted in favour of your preferred FOV - which end of the zoom you use the most.[/FONT]
[FONT=Courier New, Courier, mono]Further muddying the waters, it seems to be beyond the limits of mass production technology to make a lens this complicated, with such fine tolerances, and to make them all the same. More than any type of lens, wide angle zooms are bedevilled by sample variation - likely you have heard many rumours about 'good' and 'bad' specimens and stories about manufacturers calibrating them back to nominal spec.[/FONT]
__________________________________________

Wonder how Red will cope with "mass production" of their lenses?

I imagine that is why some of you guys are so damn good at doing what you do. Once you start to understand the delicate variations of lenses you can exploit them to your particular advantage.
Rarely is anything black and white it would seem. :dankk2:
Though the link seem to be?????

Michael
 
This awesome thread has made it pretty clear that if you want S35 handheld zoom, you have to settle for 3x with today's technology.
Maybe Diffractive Optics elements (Canon) will change the thing a bit.
But for longer zoom we'll have settle for S16 or ENG lenses.

For over-all use (including very controlled situations) the problem with ENG lenses if the focus pulling. Many lenses have critical distances on the barrel just millimeters away each other. So in my experience it is really focusing by hunch when you are at tele end and open aperture and try to pull eg. from 4.5m to 5.5m.
But in many cases ENG lenses might be the best option. I've seen stills were BBC nature documentary shooters were using ENG lenses with S16 arris and aatons.
Maybe there just should be somekind of gear shift in focus barrel in these ENG lenses and then they could be used everywhere.

ps. there was talking about using canon xl's lense in this thread. There it should be remembered that xl's lenses that have electronic focusing do not focus by moving the glass elements but instead moving the ccd block like all fixed lense cameras (like hvx).
 
toke lahti said:
There it should be remembered that xl's lenses that have electronic focusing do not focus by moving the glass elements but instead moving the ccd block like all fixed lense cameras (like hvx).
Click to expand...


What?
 
If the focus assist is real accurate on RED, and the onboard screen has good resolution, refresh rate, etc., which should enable the effective focusing of ENG-style 2/3" long zooms. RED has said they are planning to produce an EVF. If the EVF is engineered correctly, in tandem with a good focus assist utility, critical focus by a single person using RED with a 2/3" ENG style lens should not be a problem. This is the same thing that ENG-style shooters are used to doing every day with other high definition cameras (F700, F750, F900, Varicam), getting accurate focus and exposure on high definition footage by themselves. They don't "pull" focus, they rack focus by themselves. No focus puller, no tape measure, no millimeter barrel markings, etc. Why would it be harder to do this same thing on RED with a 2/3" ENG-style zoom? It wouldn't be and shouldn't be.

Those of you that have a strictly cine-style production background should realize that ENG-style shooters are bringing different field production techniques to a RED 2/3" zoom/1080p/1080i/720p working environment. Techniques that are effective, proven by years of field use, and that don't require the large crews and procedures of cine-style shooting.

I shoot both ENG-style and cine-style and merely use the style that best fits the project and budget. In ENG-style production, using ENG-style lenses, we're used to operating in a WYSIWYG manner in HD resolutions, and trusting our electronics (EVFs, LCDs, etc.). It's a different mindset than traditional cine-style production, where we're using OVFs, follow focuses, focus pullers, millimeter markings, tape measures, etc. Both workflows are valid, but if traditional cine-style shooters are willing to adopt TV/video style electronics, why not also spread their skill sets into learning how to use TV/video style shooting techniques for RED + 2/3" ENG-style zoom lens in 1080p, 1080i, and 720 formats when the project calls for it as being the easiest, and most cost-effective workflow? Being one who regularly shoots both styles, I'd recommend that traditional cine-style shooters approach a RED/2/3" lens/HD format project with an open mind and learn some techniques and accessory setups from longtime ENG-style shooters. Yeah, there are times and projects where you may want to accessorize a 2/3" ENG-style zoom lens with cine-style gear (follow focus, matte box, French flag, etc.), but why not just go to S16 cine-style lenses for such projects, and use the 2/3" ENG-style lenses on RED for projects where you can use them with the techniques and equipment that they were designed for?

Gibby
RED #8
www.cut4.tv
www.4umat.com
 
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using S16 lenses ENG style?

using S16 lenses ENG style?

good thoughts and advice Gibby!

I'm experienced with ENG style cameras/lenses and wondering how different and challenging using a S16 lens is going to be?
I've never used S16 lenses.

When shooting I tend to manually zoom and focus with my left hand, quickly adjusting to give the framing and focusing that I want (I rarely zoom in a shot - don't like it for some reason - only if it's really called for).

How will shooting for me with a S16 lens be different?

I will only be able to afford one basic zoom to get me started with RED. (I'll also be buying one wide 35mill prime for water shooting :love4: )

Buying a 2/3" ENg lense makes the most sense (user friendly and what I'm use to), however I'd like to have the option to shoot either 1080p OR 2K for other projects - I'm planning on RED helping me to expand my skills and the styles of projects I take on.

i.e. does it sound practical to consider one type of lense for both 1080p and 2K???

Thanks for everyone's contributions and knowledge sharing - I'm addicted to this forum!!!!
 
macgregor said:
What?
Click to expand...
Focusing in most 1/3" cameras is not made by moving optical elements in the lens, but moving the ccd block. This way it is much more cheaper to make the lens that have only moving elements for zoom.
And that's why we are having these "infinite rolling" focusing rings.
 
Gibby said:
Yeah, there are times and projects where you may want to accessorize a 2/3" ENG-style zoom lens with cine-style gear (follow focus, matte box, French flag, etc.), but why not just go to S16 cine-style lenses for such projects, and use the 2/3" ENG-style lenses on RED for projects where you can use them with the techniques and equipment that they were designed for?
Click to expand...
You are absolutely right, like always, but I think poor indie shooter's dream would be a lens that you cold use for both technics.

So far there has been no small lcd's that have even full sd-resolution, so I see the biggest challenge for RED to introduce a camera which has a real WYSIWYG lcd/vw for hd or even 4k work.
 
Hey bruddah Nalu! Howzit?

From our conversations, and what you say you want to shoot, I think that a good S35mm wide prime or 35mm photo wide prime is the best lens choice for shooting 2k or 1080p surfing footage in the water with a housing.

For shooting surfing footage from land, the choice is more complicated. If you use a 2/3" HD zoom, you'll be limited to 1080p, 1080i, or 720p, which should be fine for the surfing "films" or HDTV surfing programs you want to do. No 2k possible on RED with 2/3" B4 lenses (see format grid). If you really want to include 2k with the other lower resolutions, then S35, 35mm, and S16 are your only options. If you're shooting a lot of surfing simply panning right-to-left (or vice versa), a S16 zoom may work for you for 2k, but based on what you described your surf shooting needs are, I feel that the 2/3" HD ENG lens is a much better choice. I've shot a ton of surfing and water sports over the years - in water with housings, and from land with zooms. In shooting from land, the focal length changes constantly so a zoom is a necessity, and being able to easily both zoom and rack focus are critical.

In summary, When I shoot water sports with RED I will use a good S35 or photo wide prime, and when I shoot water sports from land I will use a good 2/3" HD ENG-style zoom, preferable with a 2x extender, and a remote servo zoom unit on the tripod handle. Using the servo zoom will allow you to do the constant panning, tilting, zooming, and rack focusing you need to do to frame tight shots of sports action. If you go with a S16 zoom for that, it won't be as easy to get the footage. With RED you can do 1080p 4:4:4 or 4:2:2 in camera footage at 120 fps, which is all you'll need for surf films or HDTV. The 2k frame is only slightly larger than 1080p so you wouldn't gain that much by shooting surfing in 2k with S16. You're after affordability and mobility, so S35 or 35 zooms for your 2k shooting wouldn't be an option for you.

I can't wait to take another trip down to Australia, this time with my RED camera, join you and other mates of mine down there who have reserved RED cameras, and then shoot some good surfing footage!!

Gibby
RED #8
www.cut4.tv
www.4umat.com
 
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Thanks for the speedy response Gibby. All good here (but the surf's blown out!).

Hear your logic loud and clear about using a good 2/3" HD lens with a 2X extender. However :) I still feel drawn to idea of a S16 lens (with a 2X) just because it will give both options.

Dropping the thought of shooting surfing from land and it's requirements what would your advice be??

I've got a feeling quite a few other people are in a similar boat to me. Stretching themsleves to purchase a RED and need a basic zoom "starter lens" that's going to get them shooting (adding other lenses latter).
The holy grail! - is a lens of good quality, covering a range of focal lengths that gives us plenty of options in shooting formats and styles (let's forget 4K for now!).
 
Got ya...

For what you want to shoot, it all boils down to budget on zooms then. Older used S16 zooms are affordable, but they won't give you a real sharp image. Newer S16 zooms will cost you more, but the image will usually be quite a bit better. A used 18x 2/3" HD ENG zoom can be bought for around $6.5k USD, and a 2x will be around $1k USD more, so the outlay is around $7.5k. Cheap older S16 zooms can be found for around $2.5k USD, but frankly the image isn't that good. A better used S16 zoom may be around $5k USD and a 2x extender maybe $1.5k, so the outlay may be as low as $6.5k USD, but then you'd need a matte box, follow focus, etc, so the outlay should be higher. If it was me, I'd probably buy the 2/3" lens first because it may be easier to generate contract and freelance revenue with it, and there are less accessories I'd need to buy for the ENG lens. Later on I'd buy a good used S16 zoom.

Cheers...

Gibby
RED #8
www.cut4.tv
www.4umat.com
 
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toke lahti said:
Focusing in most 1/3" cameras is not made by moving optical elements in the lens, but moving the ccd block. This way it is much more cheaper to make the lens that have only moving elements for zoom.
And that's why we are having these "infinite rolling" focusing rings.
Click to expand...


If you move the CCDs block, you would eventually be able to focus. But you would change the framing too. You would notice it for sure. In fact, the more distance you make, the more macro the lense will become.
Just as large format studio cameras do.
I think you are wrong at some point.
 
nalu said:
I've got a feeling quite a few other people are in a similar boat to me. Stretching themsleves to purchase a RED and need a basic zoom "starter lens" that's going to get them shooting (adding other lenses latter).
The holy grail! - is a lens of good quality, covering a range of focal lengths that gives us plenty of options in shooting formats and styles (let's forget 4K for now!).
Click to expand...

Hey Nalu. I'm in the same boat definitely!

From Gibby's post I assume you're an aussie like myself! I'm in South Australia and have been wondering who else in this state will be shipping in a RED. We have a small market here, so I guess this is business research!

As for lenses, this has been a head scratcher! I'm counting on lens rental to get me started. I think 2/3" will get the most work, especially with that possible zoom range.
 
If you move the CCDs block, you would eventually be able to focus. But you would change the framing too. You would notice it for sure. In fact, the more distance you make, the more macro the lense will become.
Just as large format studio cameras do.
I think you are wrong at some point.
Click to expand...

On lower-quality lenses, changing the focus causes a "breathing" effect where the zoom changes. Moving the CCD block compensates for this.

I don't know much about optics though, so I could be wrong. It would be neat however if the red lenses co-ordinated with the camera in this fashion... it would allow better lenses I think??
 
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