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-   -   Need opinion on NIKON KIRON 70-210mm lense (https://www.dvinfo.net/forum/alternative-imaging-methods/88114-need-opinion-nikon-kiron-70-210mm-lense.html)

Tim Bickford March 4th, 2007 02:48 PM

Need opinion on NIKON KIRON 70-210mm lense
 
I have a LetusXL Flip v2 on order. I fugure, while I'm waiting on delivery, I will hunt for some Nikon lenses. My father-in-law is letting me use one of his lenses. The lense is a NIKON KIRON 70-210mm. The lense is in mint condition. Can anyone tell me what kind of results that I may expect if I use this with the LetusXL Flip v2.

I found one on Ebay... this link.

http://cgi.ebay.com/NIKON-KIRON-70-2...QQcmdZViewItem

Thanks..

Cory Lange March 4th, 2007 06:27 PM

Dark grainy footage...

Tim Bickford March 4th, 2007 06:32 PM

Can you elaborate please?

Tim Bickford March 4th, 2007 06:34 PM

For what it's worth. I found this...

Like many lenses of that era, the Kiron 70-210mm f/4 attempted to cater for every conceivable user, with lens mounts for Canon, Konica, Mamiya, Minolta, Nikon, Olympus and Pentax cameras. It has a couple of interesting features, the first of which is the 'zoomlock' button on the 'rubberised' grip. This allows the photographer to zoom to a chosen focal length and then 'lock' the lens at that point. This could be useful if you wanted to work only at the longest end of the zoom, for example, or to reduce the chance of lens 'slippage' if the camera is pointing downwards.

The second feature is known as 'focustop', which uses two rings at the base of the lens just in front of the aperture dial, to limit the focus range. For example, one ring could be set to ten metres and the other to 15 metres, effectively limiting the point of focus to the five metres between.
Despite universal appeal and unique features, the £140 Kiron 70-210mm f/4 hardly set the world alight. Indeed, on a six-step scale from 'poor' to 'excellent', it managed an 'average' rating (two steps up from poor) for central definition and optical balance and 'good' (two steps down from excellent) for image contrast, edge definition and overall performance. If these steps were transferred to a numerical score (1 for poor and 6 for excellent) it would total 18/30. By comparison, the Tamron 70-210mm f/3.5, its 'rival' at the time, scored 'very good' in each category – or 25/30.
To order a full copy of this, the 1982 test or the manual, contact Old Timer Cameras on 01707 273773.

Bob Hart March 4th, 2007 09:55 PM

On a Mini35, your lens would have only one f stop number of available aperture adjustment below the f5.6 limit recommended by P+S Technik.

There have been varying accounts with varying lenses of where that limit is for the Letus35.

In my own personal experiments with the Letus Flip for Canon XL, this limit appeared to be f3.5 before groundglass artifacts became observable in the image on a production monitor with standard or wide lenses.

Some lenses yielded a higher limit than others with one, a genuine Nikon zoom, yielding acceptable images at f11.

Recommended lenses are those which have an available aperture of f1.8 or wider.

Varifocals or zooms require much more precision relating to their flange to focal plane mounting position.

Your lens will have three likely strikes against it :-

Inablilty to provide images with satisfactory brightness and contrast except in bright outdoors daylight conditions.

Inability to maintain sharp focus across the entire zoom range.

Groundglass artifacts may remain visible even with the lens at its widest aperture setting, which for many lenses is also the worst setting for image sharpness.

Zooms also are less sharp than prime lenses. With groundglass based image relay to video, you need to project as sharp and high contrast an image onto the groundglass as you can.

The groundglass diffusion reduces apparent brightness and contrast and introduces a multiplier effect on image softness.

Tim Bickford March 5th, 2007 07:00 PM

Bob-

Your explanation is fantastic. Thank you for taking the time to explain. Now I need time to digest.

Thanks again!

Cory Lange March 5th, 2007 10:56 PM

what he said :)

Bob Hart March 6th, 2007 06:15 AM

Tim.

If you want a bit of an idea what to expect, this address will get you to a music clip shot with an unholy alliance of cameras and adaptors in a less than ideal lighting circumstance.

Sony HVR-Z1P direct-to-camera. Wide master high viewpoint.
Canon XL1 direct-to-camera Wide body-level viewpoint.
Sony HDR-FX1 plus AGUS35 and f1.4 85mm Nikon lens. POV sound console.
Canon XL2 plus LETUS35 and f1.4 85mm Nikon lens. Close-ups and roving.

All cameras were manually whitebalanced.

Lighting was overhead pin spots, no added lights. I had to shoot with the Letus and its prime lens wide-open, likewise for the Agus. As a result, the adaptor footage is a bit soft. No colour grade or adjustment of levels has been done. The clip is as shot, just cut together and exported.

http://www.brightcove.com/title.jsp?title=570589631

Christopher Witz March 6th, 2007 08:32 AM

they sound like cracker.... one of my favs......

Tim Bickford March 18th, 2007 08:52 AM

Thanks for all the advice and suggestions. I'm kinda working without a net here. Could anyone suggest a Nikon lense that would be a good place to start. Perhaps I could pick one up on Ebay or the local camera shop. I'm just not sure....

Thanks

Bob Hart March 18th, 2007 11:45 AM

A Nikon f1.8 50mm might be a good starting point. For a 24mm wide image off the groundglass, 50mm is a bit on the telephoto side. It presents the normal human field of view to a 36mm wide still-camera frame thus is called a "normal" lens for that format. It should not be expensive as a used item.

Some older Nikon f1.2 50mm lenses turn up used from time to time. I have an older one which is scratched, yet still yields a nice image.

Ebay has a Nikon f1.4 50mm up for auction at the moment.

A 28mm or 35mm lens would be closer to the normal field of view for the Letus35 flip for XL and some other adaptors. An f1.8 lens in those focal lengths starts to get a little more expensive or may not be available for Nikon mount as Nikon.

There is the Sigma in 28mm f1.8 in Nikon mount. I have encountered two styles of the same. One has the window with focus marks, another has no window and focus marks on the focus ring.

They are okay but the image may jump as you pull focus because the front element moves and is a generous fit in the body. Preloading the moving front group with a rubber band to a nearby filter box rod is not elegant but helps.

There is genuine Nikon 28mm as f2. Nikon made a 28mm f1.4 which has been noted in internet posts as one of their best. It is also quite rare, sought after and being no longer made makes it very expensive.

The moving elements in older metal barrelled wide aperture Nikon lenses have a very snug fit and high friction lube on the fine threads which move them. They tend not to jump when pulling focus.

As the lube ages, it can become dry and the lens movement becomes very stiff in one direction.

Such a lens should be serviced and not be operated in this condition as wear will occur due to no lube and added pressure upon the thin internal key which keeps the elements themselves from turning with the focus ring.

You'll end up with a lens that does move slightly as you change direction in your focus pulls. The metal bodied lenses with draggy friction lube may screw out of the reversable Letus mount unless a locking pin or radial screw is added to be mount to prevent this.

Some older versions also contain elements bonded with an older adhesive which tends to go yellow and separate. Some early ones apparently also contain thorium glass which because of low level radioactivity, degrades over time with a yellow hue becoming apparent.

Lenses with separating elements can be repaired. Discoloured thorium glass cannot be restored. Fortunately, the fine variations of white balance in video cameras takes care of it whereas it can be an impediment to film work.

Tim Bickford March 19th, 2007 10:25 AM

Bob-

Thanks again!

I'll start looking around on Ebay. I'll also check out the local camera shop. There are a few good ones in my area.

I got an email from Quyen Le yesturday. He is working on my unit right now. I guess I better get moving on the lense.

Thanks again!

Cary Lee March 19th, 2007 10:43 PM

I'm glad Quyen emailed you...hopefully I will get mine soon after yours. Another place you might look for lenses is Craigslist. I just googled it with my city (L.A.) and found a 24mm f2.8 for only $60 bucks. Plus I got to inspect it before purchase. Another place is pawn shops.

Tim Bickford March 20th, 2007 06:37 PM

Cary,

Thanks for the lense tips. I think I'll be spending some time at the pawn shops.

Quyen Le must be very busy. I've tried not to bother him. I'm hoping to get my unit before the end of the week. I'm guessing it may be done by then.

I hope you get yours soon too!

Cary Lee March 20th, 2007 11:35 PM

i haven't heard from him...so I take it he is backordered a lot...but hopefully he will sent me an email and let me know where my order stands.


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