garyfergus
Member
I've used a Contax 645 for about two years, together with a full compliment of lenses, and I've never been completely satisfied with the results from the 140mm, 210mm, and 350mm lenses. The wides are terrific, and the 120mm Macro is an outstanding optic, but the 140mm and 210mm, and to a lesser extent the 350mmm, have always left me a bit flat. The 140mm and 210mm are very even performers across the frame, and they all have that signature Zeiss quality of very smooth transistions from in focus to out-of-focus. However, none of these three lenses has really impressed me with their sharpness. I've tended to blame myself, too windy for the tripod, shutter speed a bit too low for handholding, not quite accurate enough with the focus override etc.
I've just run a fairly basic test, and the 140mm and 210mm in particular weren't very impressive. You can see 100% crops in the "Test Photos" gallery.
I taped a broadsheet newspaper to a wall (the newspaper is about 30 inches across the long side) and set up a Contax 645 on a tripod, moving the camera progressively further back so that the newspaper consistently filled the frame with a 120mm, 140mm, 210mm, Hasselblad 180mm mounted via an adapter, and 350mm lens. All the posted shots were taken at f4.0.
The film used was Provia 100 in a 220 vacuum back, scanned at 4000 dpi on a Nikon 8000ED. A heavy tripod, mirror lock up and a cable release were used for each shot. I appreciate it's hardly scientific, and in particular the focusing and alignement have to be questioned. All I can say is that I focused carefully, checking auto focus with a loupe directly on the focusing screen. At these magnifications (a 30 inch subject) the depth of field at f4.0 is the same for all focal lengths, about 100mm. If we halve it to be cautious that still gives 50mm. The surface of the newspaper had ripples that were about 5mm deep, and maybe misalignement introduced a further 20mm discrepancy from corner to corner, but that's still a total error that's well within depth of field limits.
Because the 140mm and 210mm were so inferior to the 120mm I did some further research. This is what I found.
1. The American magazine "Popular Photography" ran a comparison between Mamiya and Contax using 45mm, 80mm and 210mm lenses. The 45mm was pretty much a draw. The 80mm saw the Mamiya take a small advantage, but as the Contax lens is an f2.0 available light lens that's to be expected. However the 210mm was a different matter, the Contax 210mm significantly underperformed the Mamiya lens. You can see the charts and read the full report on the Mamiya web site.
2. The Zeiss web site shows the MTF curves for all their lenses across several camera manufacturers. All their lens tests are standardised. Comparing Contax to the Hasselblad equivalents shows that the Contax wide lenses are indeed world class, and the 120mm Macro is absolutely outstanding by any measure. However Zeiss's own figures put a question mark over the 140mm, 210mm, and 350mm. The 140mm underperforms the Hasselblad 150mm, the 210mm is on par with or maybe slightly better at the edges than the Hasselblad 250mm (which is a fifty year old design!), but both are significantly below the performance of the Hasselblad 180mm or the Hasselblad 250mm Superachromat. Looking at the Contax 350mm Tele-Apotessar it's clear that despite the impossing name and frightening price it's way, way down in performance terms when benchmarked against other exotic Zeiss optics such as the Hasselblad 350mm Tele-Superachromat or the Hasselblad 300mm Tele-Superachromat, or the Hasselblad 250mm Superachromat. It seems that in the world of Zeiss the appelation "Superachromat" means a lot more than "Tele-Apotessar"!
3. The Photodo web site has lens tests across many manufacturers. I believe these tests were made by Hasselblad employees in their spare time using Hasselblad's optical bench. Unfortunately the performance curves have recently been removed from their site, leaving just a virtually worthless single numeric score for each lens. However I downloaded a number of their detailed charts some time ago. Looking at these shows that the Zeiss charts are largely substantiated, with the Contax 140mm and 210mm coming out as indifferent performers.
4. Finally, the Hasselblad web site gives the MTF curves for their 645 H1 lenses manufactured by Fuji. The advice is always given that you can't compare MTF results between manufacturers, however I suspect that Hasselblad have used their own Zeiss optical bench with the same testing methodology that Zeiss used for the Contax MTF charts. They show that across the wide angles the H1 and the Contax 645 are very similar performers. However, matching the H1's 150mm and 210mm against the Contax 140mm and 210mm shows the now familiar story of substantial Contax underperformance.
When I look at the posted shots I'd put the Contax 120mm as the best performer. Followed by the 350mm and the Hasselblad 180mm at roughly the same level. This surprised me as I've used this 180mm lens for fifteen years, when mounted on a Hasselblad body I get the impression it fully matches the results I get with the Contax 120mm. I wonder if its performance is compromised slightly by the adapter needed for the Contax 645 body? Bringing up the rear, and trailing by some distance, are the 140mm and 210mm. Incidentally, I haven't posted the results here but I also tried them with the x1.4 Contax multiplier, and that certainly doesn't do either the 140mm or the 210mm any favours!
So, what does the forum think, have I got bad s&les of these lenses, did I screw up the test, or maybe mis-read the additional evidence? Or are the 140mm and 210mm the weak links in the Contax system?
I've just run a fairly basic test, and the 140mm and 210mm in particular weren't very impressive. You can see 100% crops in the "Test Photos" gallery.
I taped a broadsheet newspaper to a wall (the newspaper is about 30 inches across the long side) and set up a Contax 645 on a tripod, moving the camera progressively further back so that the newspaper consistently filled the frame with a 120mm, 140mm, 210mm, Hasselblad 180mm mounted via an adapter, and 350mm lens. All the posted shots were taken at f4.0.
The film used was Provia 100 in a 220 vacuum back, scanned at 4000 dpi on a Nikon 8000ED. A heavy tripod, mirror lock up and a cable release were used for each shot. I appreciate it's hardly scientific, and in particular the focusing and alignement have to be questioned. All I can say is that I focused carefully, checking auto focus with a loupe directly on the focusing screen. At these magnifications (a 30 inch subject) the depth of field at f4.0 is the same for all focal lengths, about 100mm. If we halve it to be cautious that still gives 50mm. The surface of the newspaper had ripples that were about 5mm deep, and maybe misalignement introduced a further 20mm discrepancy from corner to corner, but that's still a total error that's well within depth of field limits.
Because the 140mm and 210mm were so inferior to the 120mm I did some further research. This is what I found.
1. The American magazine "Popular Photography" ran a comparison between Mamiya and Contax using 45mm, 80mm and 210mm lenses. The 45mm was pretty much a draw. The 80mm saw the Mamiya take a small advantage, but as the Contax lens is an f2.0 available light lens that's to be expected. However the 210mm was a different matter, the Contax 210mm significantly underperformed the Mamiya lens. You can see the charts and read the full report on the Mamiya web site.
2. The Zeiss web site shows the MTF curves for all their lenses across several camera manufacturers. All their lens tests are standardised. Comparing Contax to the Hasselblad equivalents shows that the Contax wide lenses are indeed world class, and the 120mm Macro is absolutely outstanding by any measure. However Zeiss's own figures put a question mark over the 140mm, 210mm, and 350mm. The 140mm underperforms the Hasselblad 150mm, the 210mm is on par with or maybe slightly better at the edges than the Hasselblad 250mm (which is a fifty year old design!), but both are significantly below the performance of the Hasselblad 180mm or the Hasselblad 250mm Superachromat. Looking at the Contax 350mm Tele-Apotessar it's clear that despite the impossing name and frightening price it's way, way down in performance terms when benchmarked against other exotic Zeiss optics such as the Hasselblad 350mm Tele-Superachromat or the Hasselblad 300mm Tele-Superachromat, or the Hasselblad 250mm Superachromat. It seems that in the world of Zeiss the appelation "Superachromat" means a lot more than "Tele-Apotessar"!
3. The Photodo web site has lens tests across many manufacturers. I believe these tests were made by Hasselblad employees in their spare time using Hasselblad's optical bench. Unfortunately the performance curves have recently been removed from their site, leaving just a virtually worthless single numeric score for each lens. However I downloaded a number of their detailed charts some time ago. Looking at these shows that the Zeiss charts are largely substantiated, with the Contax 140mm and 210mm coming out as indifferent performers.
4. Finally, the Hasselblad web site gives the MTF curves for their 645 H1 lenses manufactured by Fuji. The advice is always given that you can't compare MTF results between manufacturers, however I suspect that Hasselblad have used their own Zeiss optical bench with the same testing methodology that Zeiss used for the Contax MTF charts. They show that across the wide angles the H1 and the Contax 645 are very similar performers. However, matching the H1's 150mm and 210mm against the Contax 140mm and 210mm shows the now familiar story of substantial Contax underperformance.
When I look at the posted shots I'd put the Contax 120mm as the best performer. Followed by the 350mm and the Hasselblad 180mm at roughly the same level. This surprised me as I've used this 180mm lens for fifteen years, when mounted on a Hasselblad body I get the impression it fully matches the results I get with the Contax 120mm. I wonder if its performance is compromised slightly by the adapter needed for the Contax 645 body? Bringing up the rear, and trailing by some distance, are the 140mm and 210mm. Incidentally, I haven't posted the results here but I also tried them with the x1.4 Contax multiplier, and that certainly doesn't do either the 140mm or the 210mm any favours!
So, what does the forum think, have I got bad s&les of these lenses, did I screw up the test, or maybe mis-read the additional evidence? Or are the 140mm and 210mm the weak links in the Contax system?