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View Full Version : Gold Dot Dagor, 355 Kern, Initial impressions



Jack Flesher
8-Jun-2006, 18:18
I did a quick test of this lens today primarily for resolution. Unfortunately it was windy at my house today so capturing a 'real' image was not feasable.

First off, this lens is sharp! Very sharp, corner to corner on an 8x10 frame. I tested the lens on my Arca 4x5 with my Betterlight scanning back and shifted/rise to get an approximation of an 8x10 corner. My test target was positioned 7 meters from the camera.

At that 7 m distance (relatively close) it made over 50 LP/mm at the center wide open. Interestingly it did not get significantly sharper stopped down, making 54 LP/mm at f22. Moreover, I shifted/rise my camera to approximate the corner of and 8x10 frame and it made 52LP/mm at there both wide open and stopped down(!) I would say this is excellent for an 8x10 lens as I have seen modern plasmats not cross the 50 LP/mm threshold.

While resolution does not change significantly as you stop down, contrast and the appearance of the image both do. Contrast improves significantly by f11 and continues a bit to f16. After f16 contrast is simply outstanding. Wide open the lens shows haloing in the bright highlights -- sharp image inside a soft glow with the sharp image quite dominant -- though this effect disappears totally by about f14. Bokeh is phenomenal, buttery smooth both in front of and behind the subject with smooth transition. OOF highlights appear a bit rougher than my Cooke PS945's, but still outstanding.

So my initial impressions are very promising, but obviously I need to put a few frames behind in real world situations so some more time will tell. I'll post updates as I have them.

Oh yeah, since it was windy outside and I know some of you want visual feedback, so I did capture a dollar bill on my test target at the approximate position of the upper RH corner of an 8x10 frame (I shifted the camera 60mm and added 50mm fall). This was shot under a hot light at 7 meters -- go pin a dollar bill to the wall and step back 7 meters to see just how small it really is. This was scanned on a Betterlight scanning back and is an 800x800 crop of the extreme corner the shifted frame at f22. You will note some digital noise and the jpeg artifacting has killed some of the smoothness, but it's the best I can do over the web:
http://jack.cameraphile.org/albums/album08/8x10corner_dagor355_f22.jpg

Ralph Barker
8-Jun-2006, 19:00
For a Gold Dot, wouldn't James Madison or Salmon P. Chase have been better subjects? ;)

Not bad at 7 meters, though.

John Berry
8-Jun-2006, 23:40
It doesn't look like a lens baby, but it looks like you'll get buy. I'm up for adoption if you need an heir.

Mark Sampson
9-Jun-2006, 04:34
It makes you wonder why they ever quit making that lens. (and for our international members, James Madison's portrait appears on the US $5000 bill.)

Jack Flesher
9-Jun-2006, 08:51
Lens Baby...

I don't think a lens baby could render the "washington" print from 22 feet away -- especially at the corners of an 8x10 frame ;)
For our international friends, the print under George's portrait is about 3-point font, or about 0.5 mm tall...

Christopher Perez
9-Jun-2006, 09:59
Amazing optic, that Kern Dagor is. 355mm? Wow!

Now, who was saying that modern glass was better than some of the old stuff??? :) :) :)

Jack Flesher
9-Jun-2006, 10:35
Amazing optic, that Kern Dagor is. 355mm? Wow!

Now, who was saying that modern glass was better than some of the old stuff??? :) :) :)

I hear you Chris! Interestingly, in the Dagor vs Plasmat thread Steve Hamley explains that older German Dagors are even sharper than the Kern -- they must be freaking phenomenal!!!