Phase One 55mm 2.8 LS

[dlavay]

Does anyone have experience with this lens? As part of a new P1 IQ160 system I acquired a P1 150 2.8 AF which is tack sharp throughout the center and central edges of the frame, the 80mm 2.8 LS which shows similar image quality and the 55mm 2.8 LS which is totally different story. I have had 3 copies, all showing the same characteristics:
Very poor central sharpness at f2.8 and f4. Satisfactory to excellent central sharpness at f5.6 and up.
Absolutely horrible (and unusable) central edge sharpness at all apertures until f11 when the edges become marginally acceptable. This involves 30% of the frame on the right and 20% on the left and is not meant to include the corners. Noticeable deterioration begin at f16 due to diffraction.
From my perspective, these characteristics make the lens effectively a 1 f stop piece of glass unsuitable for landscapes and group portraiture unless one is willing to perform major cropping. And if such cropping is done, one has to ask why she/he is using a MF rather than D3x or 1DsIII. Moreover, the necessity of using such a small aperture largely negates the advantage of a leaf shutter mechanism.
I have been told by Digital Transitions and Phase One that this is normal for this lens even though they both have stated that the lens performs on par or better than the 80mm LS which it surely does not. Resolving this issue with the manufacturer and vendor is another issue, but in the meantime I need a wide angle in the 35-55mm range. Can anyone make a suggestion based on personal experience?

[MichaelEzra]

If this info helps in any way, I have Mamiya AF 55 F2.8 and it is sharper than Mamiya AF 80 mm F2.8

[dlavay]

Thanks for your reply. May I ask if that is a LS (leaf Shutter)? I can certainly sacrifice this for a sharp moderate wide angle as you have suggested.

[PaulSchneider]

Forget any focal length below 80mm for ultimate sharpness on your 645 body.

Get a tech cam for this segment.

The 80mm LS is great, sharp to the corners.

But the 55 is disappointing. The first one I had got replaced by Phase One without discussions, because even they themselves realized it was a horrible copy I got in the first place. The left side was way off in the corners. My replacement is kind of better but still has a noticeable sharpness fall-off in the corners.

The 43 XL I have on the other hand is on another level. When you get into tech cam stuff you will realize what your system really is capable off. I'm afraid that you must be really lucky on the low-end to get tack sharp lenses.

[dlavay]

Your suggestion is most appreciated, very helpful and obviously based on the kind of wisdom obtained through personal experience.

[Paul2660]

I can't speak to the 55mm LS, but for sure the 55mm Mamiya F2.8 is excellent lens for the price point.

Mine is tack sharp fro F8 to about F14, corner to corner.  This particular lens has used on a P45+, IQ160 and IQ180.  I was always impressed by it's results on the P45+ but was pleasantly surprised at what I was able to get up to the 180. 

The 55mm F2.8 non LS is an easy lens to find used and there are many out there for sale.

From all the reports I have read on the 55mm LS, they have been stellar, nothing like your results on 3 sep. lenses.  I would for sure pick up a Mamiya 55 AF F2.8 and give it a try, I don't think you will be disappointed.

Paul Caldwell

[HarperPhotos]

Hello,

I'm not sure what sort of photography you are wanting to do with your 55mm lens but may I sagest the Mamiya 50mm manual focus shift lens.

I have this lens and optically I find it excellent and as well having the added advantage of been able to shift.

http://www.ebay.com/itm/Mamiya-Sekor-Shift-C-50mm-1-4-Lens-/180782885863?pt=Camera_Lenses&hash=item2a177febe7

Regards

Simon

[MichaelEzra]

Thanks for your reply. May I ask if that is a LS (leaf Shutter)? I can certainly sacrifice this for a sharp moderate wide angle as you have suggested.

Mine is not the LS version.

[dlavay]

I acquired the Mamiya 55 2.8 AF new from KEH. My preliminary results comparing it with the 55 2.8 LS on the P1 645 DF are, to my eyes, quite remarkable particularly given the $3724 price differential. Center is reasonably sharp @ 2.8 @ infinity and tack sharp by 5.6. Corner and edge sharpness is more than acceptable at f4 and 5.6 and excellent @ f8. I detect no appreciable CA wide open in the center or corners although I have yet to photograph a really high contrast, brightly illuminated subject. Likewise, while a more thorough analysis of field curvature is pending I detect nothing obvious. The performance over the entirely of the frame on my IQ160 already appears to be vastly superior to the 3 P1 55mm 2.8 LS units I examined as far as my needs are concerned.

[Gary Ferguson]

I'm in the market for the 55mm LS, and I take these concerns seriously because Phase One has form in this area.

I ordered the Phase One Hartblei 45mm, despite the dealer warning me that other users all had very poor experiences. Well, my experience was just as poor, in fact it was an atrocious lens. Luckily they took it back when I upgraded from the P45+ to the P65+, and I see they've now discontinued the Hartblei.

Incidentally, I subsequently found one of the (unfortunately rare) Mamiya fitting 55mm Schneider tilt/shift lenses, which is superb.