Originally posted by zantaphia Hi.
I think it's about time I should do a 50-55 mm shoot-out. Let' see what happens!
Nice lineup! What film are they loaded with?
Regarding a 50-55mm lens shootout, I did one of my Pentax K mounts. Of course there is really no accounting for the current condition of these lenses as they are not factory fresh so I did a quick test first using my 14.6MP K20D and came up with these results.
Full res ->
http://www.fototime.com/AFA3C6EDB6A663D/orig.jpg
They look reasonable so I figure I would step it up this time using Kodak Techpan (ISO25) processed in Technidol. In the test results below, I used a 4X wide by 4X high arrangement of ISO12233 res charts shown in the bottom left. I then cropped and provided 100% of the center portions using very low compression. All results are therefore multiplied by 4.
- Second image up is the crop from my 14.6MP K20D + manual focus Pentax M 50mm F4 macro lens + Pentax auto bellows from the full frame shot of 35mm Kodak Techpan shot at ISO 25 and processed in Technidol. This is to show what K20D scanning would resolve.
- Third image up is the crop from my 14.6MP K20D + manual focus Pentax M 50mm F4 macro lens shot of the 4 X 4 chart arrangement. It is pretty much the same as DPREVIEW K20D resolution results of about 2400LPH. As you can see from my first test, all my Pentax lenses maxes out the K20D's 14.6MP sensor.
- Fourth image up is the Coolscan 9000 scan of the center portion of the shot made on 35mm Kodak Techpan shot at ISO 25 and processed in Technidol using the Pentax LX + the same Pentax M 50mm F4 macro lens. As you can see, it clearly resolves much more than the 14.6MP K20D sensor. However there are two different resolutions - Vertical of 4000LPH and Horizontal of 3200LPH. For comparison, a 24.6MP Sony A900 is rated at 3700LPH.
- The image on the right is a 4.5 optical magnification of the center portion of the full frame shot of 35mm Kodak Techpan shot at ISO 25 and processed in Technidol using my K20D and Pentax autobellows. This is 12.5 X 4 = 5000LPH. By comparison, the 36.3MP Nikon D800 tops the reschart at 3800LPH. The unfiltered D800E surpasses the 4000LPH chart used so we can't say where it reaches.
Of course if you can use Techpan it will provide much more conclusive results in determining the actual resolution of a system. However, TMAX100 - and other slow b&w, will work too.