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-   -   Exactly what Nikon zooms with Ultimate? (https://www.dvinfo.net/forum/alternative-imaging-methods/239086-exactly-what-nikon-zooms-ultimate.html)

Mike Favazza July 15th, 2009 02:28 PM

Exactly what Nikon zooms with Ultimate?
 
Can any Nikon zooms work?

Lots of choices on Ken Rockwall's site...

Do they have to be total manual?
With an aperture ring with marked F-stops?
How best to support those zooms?
Zacuto rods?
Thanks in advance.

Mike

Bruce S. Yarock July 16th, 2009 01:39 AM

Mike,
You need to go with a fast lens that has manual iris. I bought a used Tokina 28-70 for under $200 and it's ok. I also borrow my friend's nikon 80-200 f 2.8 and it's a great lens. My beaytifull nikon 70-200 vr lrns won't work because it doesn't have a manual iris. You need rails for either. I use the letus rails with my extreme.
You're better off with primes when you have the luxury. My most beaurifull lens is my nikon 85 f 1.4. I also find it important to re white balance ( time pemitting) when changing lenses.
Bruce yarock
Yarock Video and Photo

Bob Hart July 18th, 2009 10:38 AM

Bruce.


Your 70-200 might be a bit tight on the iris wide-open as is the 12-24.

Have you tried wedging the iris lever open or is there none at all on your lens? On the 12-24, a short cut, about 3/8", of orange weedwhacker cord, the type which has the splined surface is a good wedge. You sort of screw it into the slot. A groove builds in the splines on the cord and it then does not fall out.

You can adjust the iris a little and just let the lever stop against the cord but I wedge it fully open as the 12-24 is f4 wide-open and there is only one f-stop to groundglass artifact doomsday at f5.6.

Don't cut it too short or it may drop inside the guts of the lens and there will be then great lamentation. Cut it long and then trim it down afterwards.

Bruce S. Yarock July 18th, 2009 03:05 PM

Bob,
Someone else suggested that a while back, but I don't want to fiddle with such an expensive lens. Besides, you're pretty much stuck with a wide open 2.8, which would be a pain in the ass out doors. In addition, a friend gladly swaps me his 80-200 foe my 70-200 if I need it for a job ( the 80-200 is non vr, and he loves the chance to play with the vr model).
How are things down under?
Bruce yarock
Yarock Video and Photo

Mitchell Lewis July 23rd, 2009 02:10 PM

Just don't by any "G" or "DX" lenses and you'll be fine. If you want them to do double-duty (use them on a 35mm Nikon like the D700) then don't buy and AI lenses as well, as they won't autofocus.

James Huenergardt September 9th, 2009 08:38 AM

I use these Nikons:

80-200 2.8
28-70 2.8
17-35 2.8

I actually prefer zooms, as these are sharp anyway.
It's much quicker to frame your image with a zoom than to move your tripod back and forth.

But hey, that's my opinion. I know guys are really into primes. But in the end, your viewer won't be able to tell the difference.

Mitchell Lewis September 12th, 2009 11:09 AM

I totally agree with James. Unless your coming from a motion picture background where you're used to using prime lenses (have a crew to move the camera) then I'd buy zoom lenses. I have almost the identical setup to James:

17-35mm f/2.8
50mm f/1.4 (great for shooting in a very small office and still getting a blurred background)
80-200mm f/2.8

I'm looking at purchasing a 28-70mm f/1.4.

The "catch" to all this is when you shooting a f/2.8 or worse f/1.4, you're really taking a big risk that your focus won't be sharp. If you're shooting an interview for example and the interviewee adjusts their position in their chair, chances are they will go out of focus. If you shoot "wide-open" on a regular basis and external monitor is a must to monitor focus. With our EX3, I'm constantly pushing the "Extended Focus" button to double-check focus, but even with that, I get back to the office and find that some of my shots aren't as sharp as I'd hoped.

But this is why hollywood uses "focus pullers" to stay on top of all this. (something our company currently can't afford) :)

Christopher Warwick September 20th, 2009 11:20 AM

A post above mentioned not to buy any 'G' or 'DX' Nikon lenses. Is that for sure as I have a good deal on a DX lens right now.

There's a good explanation about the differences between DX and FX lenses here: Ichimusai’s Place » Blog Archive The Difference Between DX and FX Lenses

However, as we all know with the Letus, we have to zoom in quite a bit (at least to '72' on my XH A1), before I can get the full frame. Would the DX lens mean I'd have to zoom in some more to eradicate vignetting?

They say that the ultra wides, like the Tokina 12-24mm F4 AT-X124 Pro DX are more like 18mm-30. Do they mean for full frame FX SLRs?

It's all so bloody confusing! I really fancied that ultra wide too.

Bob Hart September 20th, 2009 10:19 PM

Here is a link to an old AGUS35 test clip with captions I did.


YouTube - AGUS35 TEST 4+ CENTURY - LONG SETBACK

The AGUS35 was yielding then about 22mm - 24mm area width on the groundglass. You will observe the Nikon DX 12mm - 24mm f4 zoom on wide exhibits edge brightness falloff. There is also some falloff with the other lenses because the AGUS35 did not have any condensor elements.

On the wider views you can get with the Letus, there appears a vignette at the wide end of the lens before it appears with other lenses if you back the relay zoom off.


This link is to a clip which includes vision shot with the Nikon 12mm - 24mm on a Letus Extreme.

http://exposureroom.com/members/DARA...a4ac4a5830b07/


The Nikon lens had to be zoomed in to eliminate its vignette. This lens has also a full auto iris so the iris lever has to be wedged open, not a good hack as there is no available iris adjustment.

At f4 fully wide there is only 1.6 stops of what I call "headroom" and in adverse lighting conditions, there will be a groundglass artifact with these 12mm - 24mm f4 DX zoom lenses.


So at the end of it all, there is no advantage to using a 12mm setting on a DX zoom with more relay zoom-in to get inside the vignette over using a 14mm prime film stills lens with a wider groundglass view. It is likely there will be a resolution loss through zooming in closer on the groundglass.


A good deal on a DX lens is going to give you a mantleshelf monument once you have exhausted all efforts to get it to work and if lucky, a profit when you resell it. There is nothing wrong with the lenses at all. They are just not suited to this application.

Christopher Warwick September 21st, 2009 07:14 AM

Bob,

Thank you very much for that insightful post. It's helped me not to waste my money on the DX.

So assuming we stick with the primes, in conclusion, what is best overall widest lens to go for? (Nikon mount). I read somewhere that many directors particularly like the 17mm on the 35mm ariflexes. I realise this is a whole different ballgame.

I don't mind a little distortion around the edges, but I don't mean fisheye and I don't want the picture to look like you're looking down a tube.

Bob Hart September 21st, 2009 09:40 AM

Christopher.



These are motion picture lenses, 24mm wide image to the groundglass or thereabouts. It is likely the wider lenses like a 17mm will throw a smaller footprint onto the groundglass than the longer lenses.

Some ARRI-mount lenses which are repurposed 35mm stills lenses may give you the wider stills footprint or closer to it. The wider lenses may require a tighter relay zoom-in of the camcorder lens.

Some wide lenses are designed to create what is described as a rectilinear image.

This image reproduces straight lines at the edges of the image, not the bowed lines associated with some wider lenses or accentuated in fisheye lenses, a trait known as barrel distortion.

The rectilinear lenses however still distort the image, by stretching it in diagonal directions, which is how the straight lines are reproduced across an unnaturally wide view.

I think it is safer to regard the ARRI-Mount lenses as limited to the motion picture frame sized image on the groundglass however some may reproduce an acceptable wider image.

They may not necessarily be sharper than good stills primes however may be more user-friendly in having a more extensive rotation of the focus barrel for a given focus adjustment, therefore a finer degree of control. They may also retain their sharpness to their widest iris setting and may produce better contrast than stills lenses.

They may also have focus gears fitted which enable the use of a follow-focus system and the direction of rotation will more likely be to the accepted standard which is opposite to Nikon stills lenses.

The widest sensible lens may be the genuine Nikon 14mm f2.8 or non-Nikon brands. The Sigma variant is now no longer made. It seems a little softer wide-open but is otherwise acceptable.

The Kinoptik 9.8mm ultrawide will be found on eBay from time-to-time. This is a rectilinear lens. It will vignette unless the groundglass view is confined to the motion picture frame size.

Due to the existence in most 35mm adaptors of a dust excluder glass panel and the trait of the collimation or backfocus of ultrawide lenses to be affected by an added panel of glass, this lens may need to mounted closer to the focal plane than the designed mount permits.

I achieved this by skimming a little material from the front of an ARRI B-mount to PL-Mount adaptor to allow the lens to be positioned a trace furthur rearwards. By comparison with modern lenses, the Kinoptik may now be found a little softer and flary but it was revolutionary in its day.

Christopher Warwick September 21st, 2009 11:16 AM

Bob,

Absolutely top bloke, thank you once again. After reading your post I did some researching into the various lenses mentioned on various sites and my path appears evidently clear as to my next purchase for an ultra wide.

Chris

Bob Hart September 21st, 2009 09:56 PM

Here is a link to a test which includes the Sigma-for-Nikon 14mm f2.8 and Kinoptik 9.8mm f1.8 on a P+S Technik MINI35-400 which yields the standard motion picture frame width.

YouTube - SONY PMW-EX1 - P+S TECHNIK MINI35 TEST

On some other 35mm adaptors where you can back off the relay zoom to a wider groundglass frame, the 14mm will then yield a similar field-of-view and an apparently sharper image compared to the Kinoptik because the "grain" size of the groundglass texture is scaled smaller relative to the frame size.


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