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Nicolasllasera
14-Mar-2017, 13:05
Surfing facebook I saw that Catlabs is trying to get a special order for this lens. And wanted to ask before I buy. Will this lens replace the 3 similar focal length lenses I already own. I mean with this one lens can I get away selling "my other" 3? I know it's a pretty general question but it's not a small decision and would love to hear people's opinion as I have been thinking about it for a while.

The lenses would be a 300mm f5,6, Nikkor 450mm f9 and a 600mm I still don't own...

Im leaving the link just in case someone is in the same place as me. If its against rules please take it down. Not related to them.

http://www.catlabs.info/product/cooke-optics-xva-8x10-11x14-triple-convertible-lens

karl french
14-Mar-2017, 13:16
I wasn't aware that Cooke changed their order policy. In the past you placed you order with a dealer and waited 3-4 months. No minimum order required.

It's an amazing lens. There are a number of threads in the archive that address the issues you are curious about. As an 8x10 lens of moderate coverage it is without equal in my mind. If you need a big image circle with a 300mm lens the 311mm arrangement of the Series XVa won't do the job as well as some modern f5.6 plasmat. There is no replacement of the Nikkor 450 or Fuji 600C if you want to shoot ULF. With that said I do use the Series XVa with my 10x12 cameras occasionally.

Eric Leppanen
14-Mar-2017, 22:31
Another option is to check with Robert White in the UK, and see if there is a group order requirement over there. At current exchange rates, ordering from Robert White could also save you a significant amount of money.

https://www.robertwhite.co.uk/optics/lens-mounts/large-format-copal/cooke-series-xva-triple-convertible-large-format-lens-copal-3-shutter.html

SK Grimes also used to make lens caps for the Cooke's individual lens elements when disassembled. I don't know if they are still manufacturing them but they still have a (dated) web page up:

http://www.skgrimes.com/whats-new/2003-2/cooke-vxa-installation-and-cap

I owned an XVa for awhile during my 8x10 shooting days. As for the pros and cons of using the XVa versus dedicated 300, 450 and 600mm lenses, IMHO it comes down to whether you can live with disassembling/reassembling lens elements in the field (without dropping anything!), accept the coverage limitations, and have sufficient extension on your camera to accommodate the single element focal lengths (476 and 645mm).

The XVa 311mm configuration was very sharp and had the best contrast and color saturation of any LF lens I have used, for me its only liability was somewhat limited coverage for 8x10 use.

The 476 and 645mm configurations require far more extension than corresponding dedicated lenses, and pose stability challenges in the field. Personally I just couldn't achieve results as sharp as with dedicated lenses, despite added stabilization measures (second tripod, long lens support arm, etc.). Whether this was the result of camera shake despite my efforts or optical limitations I couldn't say.

Mark Sawyer
15-Mar-2017, 16:48
One consideration is that the individual elements are going to be darker (f/16 for the rear, f/11 for the front) than most conventional lenses of the same focal lengths. Also, it's standard practice with most convertibles to use an even smaller stop for shooting to get acceptable sharpness, (I'm not sure what the situation is with the Cooke).

karl french
15-Mar-2017, 17:25
The brightness issue for the individual components is not an issue. And the Cooke Series XVa is quite sharp, with a really beautiful rendering.

Mark Sawyer
16-Mar-2017, 12:08
The brightness issue for the individual components is not an issue...

It is if you intend to use the individual components. Photographers frequently spend quite a bit for faster lenses and brighter focusing screens, so it's an issue for some of us.

I'm not denigrating the Cooke XVa; I'd love to have one. But if I was spending $4,000+ on one, I'd consider the issues, not deny they exist.

karl french
16-Mar-2017, 14:02
Based on the angle of light hitting the ground glass with the required bellows draw to use each component individually the ground glass is not especially dark. The 476 f11 is brighter than a Fujinon C 450 and the 646 f16 is only slightly darker than the Fujinon C 600. I'm not denying the issue exists (technically it would for a comparison with the Nikon M 450 and the Fujinon C 600), I'm merely suggesting it's not significant when the alternatives are considered.

The best way to buy the lens is in barrel and then find a clean used Copal 3. Certainly less than $4400. $3300 in barrel ($3100 when I bought mine a couple years ago.) + $250 for a good used Copal 3.

Sal Santamaura
16-Mar-2017, 15:13
The brightness issue for the individual components is not an issue. And the Cooke Series XVa is quite sharp, with a really beautiful rendering.I have no experience with the Cooke. However, viewing brightness has been an issue for me with slower lenses when composing/focusing, irrespective of how nice resulting negatives might be after the struggle is over.

My 8x10 Phillips Compact II is outfitted with a Satin Snow ground glass overlaid with a Maxwell fresnel. It's safe to say there's not a brighter 8x10 viewing system around. Nonetheless, despite owning both Fujinon 300mm A and 450mm C lenses, I went on to obtain a 300mm f/5.6 Nikkor W and 450mm f/8 CM Fujinon W. Not only are the latter two sharper than the former, working with them in the field is much less frustrating. Maximum aperture counts.