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August 23rd, 2005, 07:34 AM | #91 |
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16:9 video has a pixel aspect ratio of 1.2121 NTSC or 1.4568 PAL. PC video always has a square pixel aspect ratio of 1 (equal height and width). Regular 4:3 video is quite close to a square pixel (.9091 NTSC or 1.0926 PAL) and translates most efficiently to PC playback.
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August 23rd, 2005, 06:25 PM | #92 |
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Anamorphic Adapter
Got it. That explains it. I will view my footage on a 16:9 T.V to see if it gets sharper. If not I will send it in to Century. Thanks.
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August 24th, 2005, 12:07 AM | #93 |
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There will always be slight losses when using an anamorphic, even a comparatively mild 1.33:1 version as this Century is. When using film we used 2:1 anamorphics, and the losses are consequently greater of course.
An anamorphic is a wide-angle converter but in the horizontal plane only, and the cylindrical elements are never perfectly cylindrical, it's never perfectly centered on the zoom's axis and the elements introduce more flare. They also tend to restrict the zoom's range and vignette at the wide end, so you can see I'm not a fan. Their days must be numbered though. It's cheaper to buy an FX1 and shoot native wide-screen than it is to get a VX2000+Century anamorphic. tom. |
March 31st, 2006, 04:31 PM | #94 |
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Century Optics 1.33 anamorphic lens?
If there is one thing I miss in my PD-170s, it is a native 16:9 option. I've also been weighing the SD vs HD thing and have come to the conclusion that what I really need over the next 2 years is a 16:9 solution.
As many of you probably know, the CO lens is costly at around $1,200 at B&H. Aside from the cost, does anyone have any practical experience with this lens on a PD-170 or 150? In particular, experience shooting wedding ceremonies and receptions. I'm interested in hearing the good, bad or ugly. Thanks for any info. Bob |
April 8th, 2006, 06:48 AM | #95 |
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Bob, I'm in the exact same boat you're in. 2 PD170's which I really love for their color and low light performance, and a need for 16x9 output. I'm not ready to make th HDV move either. No one has asked me for HD and I too estimate about two years before I really see the ability to sell it around here. I keep going back to the anamorphic thing. I would spend the money for the adapters if I knew the output would be as good as what I am currently getting in 4x3 and if I knew that once setup corectly I could maintain full zoom through and and focusing capability. If anyone shoots with this adapter "Cetury Optics Anamorphic 1.33 Converter DS-WS13-SB" please tell us you thoughts.
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April 8th, 2006, 07:15 AM | #96 |
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You've got to realise that anything you put in front of your PD's zoom lens will degrade the image to a greater or lesser degree. A 1.33:1 anamorphic is a wide-angle converter in the horizontal plane only, and cylindrical rather than speherical (or aspherical) elements do the light bending.
But the big payoff is that you get to use the whole of the 1/3" chip to capture the 16:9 image, so even with the anamorphic's losses the gains generally outweigh them. Of course there will be side-effects (there always are). You'll need a new lens hood, you might well curtail your 12x zoom range, edge definition won't be as good as without the lens and focus will be more problematic. But as you both rightly point out - 16:9 is a here-and-now requirement whereas HiDef most certainly isn't. So the CO lens will enable you to squeeze more life out of the hugely versatile and low-light king called the PD170. |
April 8th, 2006, 08:50 AM | #97 |
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I can't speak for the PD170 however for the PD150P, I found the Century Optics 16:9 anamorphic lens does yield a clearly better result than the electronic stretch which sheds about 25% of the vertical resolution.
If you letterbox the footage and take care to de-interlace the images, the image looks to be on a par with the image from the HDRFX1 if this is intercut and also letterboxed. If you don't de-interlace the PD150 image, it will appear somewhat like looking through flywire when there is a lot of fine high contrast detail like rows of windows on high-rise buildings, checkered tablecloths or fine ripples on a lake. An old report on the web, which has since disappeared, suggested that the Optex 16:9 lens was better. This lens is apparently no longer available. But it is a while since I last enquired so it may be findable again. I found the Century vignetted a little on the left edge as viewed with the PAL camera when the lens was at its widest setting. It does not pick up the right corners or edge. This seems due to the optical path of the PD150P and PD170P which has the lens centre slightly offset relative to the centre of the CCDs. There is apparently a few more pixels with the PAL CCDs though I don't have the confirmation of that suggestion. The NTSC models may not do this. If you don't believe me about the offset, lock your cam off on a tripod after you have zoomed in and centred a target. Retreat the zoom back to wide and see if that target is still centred. I filed off about another 0.75mm off the inner left edge and corners of the plastic spacer between the two glass elements of the Century to cheat a little more field of view without the vignette but I would not recommend this practice to anyone other than lens-smiths. The corners are still vignetted slightly on full wide in an underscan image but are well gone from the TV safe-area. To fix this, a little more might have to be taken out of the existing left-side cutouts on front of the lens but in my opinion there is little point to doing it as the same field of view as the camera's own lens is already available wit a little bit of zoom-in. When you set the zoom to frame the exact same width of mage as you were getting without the 16:9, there will be no vignette. The 16:9 confers a little more wide-angle than the camera's own lens. Obviously standard DV is not the way one would want to show off HDV footage but if you are using a mix of both in a standard definition end-product to DVD-Video then the 16:9 anamorphic lens is well worth using and recommended. Whilst I had the 16:9 lens dismantled, I observed some very small chips in the outer corners of the rear element on the right side. This seemed to be due to some shock damage so I suggest very great care in handling this lens in the field and avoid knocking it, especially from the side. |
April 8th, 2006, 09:35 AM | #98 |
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Thanks for the info Bob. This sounds good. My workflow includes deinterlacing with DV Filmaker anyway so that would not be a change.
How is it to work with? Is the full zoom available? How about focusing? I was reading some info at the Cent Optics site about setting up the adapter and it appeared that there was a procedure for focusing that had to be followed. Apparently there is a seperate focus ring on the adapter. Is this something that is set up once and then left alone or does it require adjusting for every focus change you make. This will probably be a deciding factor for me since most of my work is event coverage. I would think having to work two focus rings would really be tough during events. How does that affect autofocus? I use autofocus about half the time depending on the circumstances. Thanks again for the detailed response.
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April 8th, 2006, 09:47 AM | #99 |
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If there's a choice between the screw-on and bayonet, go for the bayonet. As you're shooting through a cylindrical element it must be accurately aligned vertically, and the bayonet ensures this happens quickly every time.
The downside is that the anamorphic can't be used on other cameras using step-up rings, and this limits its second-hand sales appeal. tom. |
April 8th, 2006, 10:03 AM | #100 |
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Lamar,
Century Optics website makes focusing sound easy. They claim you should go full telephoto on your subject, focus and then zoom to wide. The image will stay in focus throughout the focal range. Wish I could get my hands on one of those for a test. Can't find anything on the net about them which seems to indicate that there aren't many out there. No wonder at $1,200 each which for me would need to be a $2,400 investment for a 16:9 wedding. Wouldn't Sony have added so much more value to the 170 if they had just included native 16:9? Decisions, decisions... |
April 8th, 2006, 10:07 AM | #101 |
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Thanks Tom, if I get it I will definitly go with the bayonet. I have read other posts about the importance of alignment with anamorphics. Do you know the outside diameter of the front of the adapter? I would need hoods or matte boxes but I can't find the diameter specified anywhere including the CO website.
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April 8th, 2006, 10:16 AM | #102 | |
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You aren't kidding. Its THE only thing that these great little cameras really fall short on. I just dropped Century Optics Sales a note with a link to this thread. Maybe they will come up and offer up some more info.
Quote:
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April 8th, 2006, 11:31 AM | #103 |
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See post below which somehow got doubled with this one.
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April 8th, 2006, 11:52 AM | #104 |
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My 16:9 has no added focus ring. There is a movable ring on the front which locks using a small thumbscrew. This is for adjusting the vertical alignment of the lens.
The bayonet version is what I have. It fits to the camera lenshood mount. The 58mm filter thread mount version is not necessarily inferior. With either bayonet or threaded version you really have to follow best practice and realign the lens everytime you dismantle it from the camera and everytime you take the assembled camera and lens out of the case after transport. The bayonet style fitting uses a clamping arrangement which does not go onto the camera exactly the same as it came off. Once fitted however, it is less likely to move in use than the threaded version. The instruction sheet which comes with the lens describes the method of attachment to the bayonet fitting which is very different to the method of attaching the camera's own lens hood. If the alignment is slightly off you will get a skewing effect on the stretch of the image and the focus may go off slightly. There is also greater chance of vignette on diagonally opposite corners once the lens starts to turn. You may find you are better off using manual focus. Also recommended on that website was operating the camera as much as possible on the f5.6 aperture setting. There are no fittings on front of the 16:9 lens for filters or hoods. Anything you attach to the lens barrel would have to be some sort of clamping sleeve arrangement. The outer diameter of the lens barrel at the front is 75mm and is 7.5mm from front to another slightly wider main body section which has a grip rim. The front section turns inside the main lens body for adjustment when the thumbscrew is slackened I would not recommend attaching filter boxes or lens hoods to the lens barrel as bumping or adjustment of the hood might turn the lens and skew the image stretch. A separate self-supporting hood or filter holder would be a better solution. The 16:9 comes with its own push-on plastic lens caps for front and rear. Adjusting the lens alignment takes a little practice and is assisted by having a test card which has at least a vertical and horizontal line crossing at the centre. The 16:9 lens causes a barrel distortion at the wide end of the zoom which may cause you a problem if you re-align the lens in the field and rely on horizontal and vertical edges in the environment. You must make sure the lines cross at 90 degrees in dead centre of the image and at the same hieght above the floor as your cameras lens centre. If you just fit a rightangled corner such as a window or doorframe into a corner of the viewfinder frame and attempt to re-align to that, barrel distortion may cause you to adjust the lens to a skewed position. It is possible to make adaptors to mount the bayonet mount 16:9 lens to other lenses with a front filter thread and I have done so to a Micro-Nikkor 55mm fitted to an AGUS35. The lenses must have internal focussing otherwise the 16:9 is skewed off alignment by the action of focussing the prime lens. |
April 8th, 2006, 01:21 PM | #105 |
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Bob,
Thank you so much for taking the time to help. I feel confident that technically this is a good option for me now. I have to figure out the cost/benefit analysis and see if it works that way. $1250 US plus rods and matteboxes for two cameras is a lot of cash. I don't know if I can make the money back for it in two years by offering a 16x9 product which is what I'd have to do to make it pay for itself before I buy new equipment. Like the other Bob said earlier, decisions decisions.....
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