Coupling PN 105 with SK 210/5.6 enlarger lens

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austrokiwi1
Posts: 350
Joined: Sun Sep 14, 2014 10:53 am

Coupling PN 105 with SK 210/5.6 enlarger lens

Post by austrokiwi1 »

I tried this combination because I could not through any great inspiration. Following along from this thread (http://www.photomacrography.net/forum/v ... hp?t=31547) and my experimentation with coupling an SK APO componon 40/2.8 HM I realized I had the necessary equipment to couple my PN with a large format enlarger lens I had. the coupling with the SK 40 and the 210 seems to be a good combination. Initially I thought the PN 105/SK 210 combination was working. Working distance at 44 mm was a bit tight for my purposes but the combination easily covers a full frame sensor. Initial observation suggested that the resultant field was flat but when I performed a test stack ( step 0.025mm) I found I was getting a less than satisfactory result. I switched from Depth map( in Helicon focus) to Pyramid and there seemed to be some improvement. PN was wide open as was the SK. However the resultant picture still isn't as sharp as I might expect. Am I seeing a failing of the SK210 or is there something else going on? Picture is reduced by 75%

Image
Still learning,
Cameras' Sony A7rII, OLympus OMD-EM10II
Macro lenses: Printing nikkor 105mm, Sony FE 90mm F2.8 Macro G, Schneider Kreuznach Makro Iris 50mm , 2.8, Schnieder Kreuznach APO Componon HM 40mm F2.8 , Mamiya 645 120mm F4 Macro ( used with mirex tilt shift adapter), Olympus 135mm 4.5 bellows lens, Oly 80mm bellows lens, Olympus 60mm F2.8

rjlittlefield
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Post by rjlittlefield »

If "PN" means Printing Nikkor, then I'm thinking the big problem is that you've dragged that lens very far away from its sweet spot at 1:1. According to http://coinimaging.com/printing-nikkor_105.html, in the section labeled "Corner Sharpness vs. Aperture", the PN's corner sharpness at wide aperture falls way off even at m=0.66. Used in conjunction with the SK 210, you're making the PN work much farther away from its sweet spot than that.

--Rik

austrokiwi1
Posts: 350
Joined: Sun Sep 14, 2014 10:53 am

Post by austrokiwi1 »

OK so I didn't work round that rule!! I also discovered I was using too large a step increment. I re did the stack but even with a smaller step increment the results weren't great. It was fun to try.
Still learning,
Cameras' Sony A7rII, OLympus OMD-EM10II
Macro lenses: Printing nikkor 105mm, Sony FE 90mm F2.8 Macro G, Schneider Kreuznach Makro Iris 50mm , 2.8, Schnieder Kreuznach APO Componon HM 40mm F2.8 , Mamiya 645 120mm F4 Macro ( used with mirex tilt shift adapter), Olympus 135mm 4.5 bellows lens, Oly 80mm bellows lens, Olympus 60mm F2.8

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