Why have video lenses anyway?

Nick Hiltgen · November 25th, 2005, 11:54 AM

Quote:

Originally Posted by Graeme Nattress

Well, they needed to design new lenses for the reduced chip size over 35mm - that's true, but they also had to make them a lot sharper too.

It's not the sharpness of the lens, per se, but how sharp the lens has to be for the pitch of the pixels in the CCD. The smaller the pixels, the greater their resolution in lp/mm, and hence the lens has to be sharper too. 35mm is a lot bigger than 2/3" and hence can get away with less sharpness for the same amount of resolution in the final image.

Graeme

That makes since, so the reason why they don't have to worry about that so much with the pro35 is because the pro 35 takes advantage of the full 35mm for the lens instead of just the smaller part that would be used for a 2/3" chip. Thanks for clearing that up for me Graeme!

Graeme Nattress · November 25th, 2005, 12:08 PM

As long as the relay lens has enough rez to get the projected 35mm image down to the CCDs, you're laughing.

Graeme

Pete Tomov · November 30th, 2005, 01:39 PM

Actually,the answer is very simple.The xl series are ment to be compact and in order to get the same FOV as the 20x with a 35mm lens you're going to have to carry around a lens that's about 1m long :)

Michael Maier · November 30th, 2005, 10:12 PM

Quote:

Originally Posted by Graeme Nattress

A 35mm lens is not sharp enough for HD though. That's why Panavision designed their primo-digital lenses as they found that their existing lenses were not sharp enough for 2/3" CCD HD, never mind 1/3" HD.

I have heard that too.. Doesn't it have to do with the lines per millimeter difference of a smaller sensor? Based on that, you would probably get more sharpness out of a lens designed for super 8 cameras than from a 35mm lens, because super 8 is much closer to the size of a 1/3" CCD. That also would have almost no magnification introduced. I would also think S-16 lenses would produce better results on a 2/3" camera than a 35mm lens.

Graeme Nattress · November 30th, 2005, 10:15 PM

If everything else was equal, yes.

Graeme

Michael Maier · November 30th, 2005, 10:23 PM

Could you elaborate?

Graeme Nattress · December 1st, 2005, 08:01 AM

You're right that lenses designed for 8mm or 16mm would be a better match for video lenses, both in focal length and sharpness. By saying all things being equal, I'm saying that although 8mm lenses should be a lot sharper, I doubt they are because so much less is expected of 8mm that some sacrifces are made.

Graeme

Michael Maier · December 1st, 2005, 08:43 AM

I understand what you mean now. Oh yeah, definitely. Specially in the case of Super 8. The cameras and lenses were of consumer grade, which I wouldn’t think could resolve HD and most had a fixed lens. More a match in terms of FL and being designed for the smaller plane. But I would think S-16 lenses like Zeiss would be up to the task of resolving HD and would be a better match for a Cinealta than a 35mm lens.
Not sure about old 16mm C mount lenses though. But the newer PL lenses should give good results I think.

Tony Davies-Patrick · December 1st, 2005, 08:53 AM

For anyone interested, Nikon made quite a selection of ultra-wide Nikkor lenses:

In 'fisheye':

6mm f/2.8 (round view)

8mm f/2.8 (round view)

and also the frame-filling FULL view 16mm f/2.8

In the more worthwhile non-fish eye lenses with 'FULL undistorted frame':

13mm f/5.6 (YES! - full 118 degree coverage without barrel distortion)

15mm f/3.5

18mm f/3.5

20mm f/3.5 & f2.8

With the Nikkor to Canon XL adapter, there is still the x7 equation of course. A wide-angle adapter such as the Optex .7 or RED EYE .5 & .7 could be used on some of these lenses to bring back the wider view (although unfortunately not on the bulbous front glass of the 13mm & 15mm, except maybe if the Red Eye is placed 'behind' the main lens).

I've not used the Canon XL 35mm lens adapter, but one advantage of using the Nikon adapter it has no extra glass in the adapter itself. It is also nice to be able to use the F/stop aperture ring on the Nikkor lens body instead of having to use the XL body dial, such as needed when using Canon black XL-16X manual lens.

(I've been using the Optex wide angle and Red eye range of adapters during this past summer & autumn, and so will try to write a review of my findings - as soon as I've caught up on the back-log of magazine articles and video editing tasks that I need to finish this winter!).

November 25th, 2005, 12:08 PM	#17
Graeme Nattress RED Problem Solver Join Date: Sep 2003 Location: Ottawa, Canada Posts: 1,365	As long as the relay lens has enough rez to get the projected 35mm image down to the CCDs, you're laughing. Graeme __________________ www.nattress.com - filters for FCP

November 30th, 2005, 10:15 PM	#20
Graeme Nattress RED Problem Solver Join Date: Sep 2003 Location: Ottawa, Canada Posts: 1,365	If everything else was equal, yes. Graeme __________________ www.nattress.com - filters for FCP

December 1st, 2005, 08:01 AM	#22
Graeme Nattress RED Problem Solver Join Date: Sep 2003 Location: Ottawa, Canada Posts: 1,365	You're right that lenses designed for 8mm or 16mm would be a better match for video lenses, both in focal length and sharpness. By saying all things being equal, I'm saying that although 8mm lenses should be a lot sharper, I doubt they are because so much less is expected of 8mm that some sacrifces are made. Graeme __________________ www.nattress.com - filters for FCP

December 1st, 2005, 08:53 AM	#24
Tony Davies-Patrick Trustee Join Date: Feb 2005 Location: Worldwide Posts: 1,589	For anyone interested, Nikon made quite a selection of ultra-wide Nikkor lenses: In 'fisheye': 6mm f/2.8 (round view) 8mm f/2.8 (round view) and also the frame-filling FULL view 16mm f/2.8 In the more worthwhile non-fish eye lenses with 'FULL undistorted frame': 13mm f/5.6 (YES! - full 118 degree coverage without barrel distortion) 15mm f/3.5 18mm f/3.5 20mm f/3.5 & f2.8 With the Nikkor to Canon XL adapter, there is still the x7 equation of course. A wide-angle adapter such as the Optex .7 or RED EYE .5 & .7 could be used on some of these lenses to bring back the wider view (although unfortunately not on the bulbous front glass of the 13mm & 15mm, except maybe if the Red Eye is placed 'behind' the main lens). I've not used the Canon XL 35mm lens adapter, but one advantage of using the Nikon adapter it has no extra glass in the adapter itself. It is also nice to be able to use the F/stop aperture ring on the Nikkor lens body instead of having to use the XL body dial, such as needed when using Canon black XL-16X manual lens. (I've been using the Optex wide angle and Red eye range of adapters during this past summer & autumn, and so will try to write a review of my findings - as soon as I've caught up on the back-log of magazine articles and video editing tasks that I need to finish this winter!). __________________ www.WILDCARP.com www.NIKON.me.uk

November 30th, 2005, 01:39 PM	#18
Pete Tomov Regular Crew Join Date: Sep 2005 Posts: 106	Actually,the answer is very simple.The xl series are ment to be compact and in order to get the same FOV as the 20x with a 35mm lens you're going to have to carry around a lens that's about 1m long :)

November 30th, 2005, 10:23 PM	#21
Michael Maier Trustee Join Date: Apr 2005 Posts: 1,269	Could you elaborate?

December 1st, 2005, 08:43 AM	#23
Michael Maier Trustee Join Date: Apr 2005 Posts: 1,269	I understand what you mean now. Oh yeah, definitely. Specially in the case of Super 8. The cameras and lenses were of consumer grade, which I wouldn’t think could resolve HD and most had a fixed lens. More a match in terms of FL and being designed for the smaller plane. But I would think S-16 lenses like Zeiss would be up to the task of resolving HD and would be a better match for a Cinealta than a 35mm lens. Not sure about old 16mm C mount lenses though. But the newer PL lenses should give good results I think.