Barry_Green
Moderator
So, I got in the first of my new batch of Zeiss ZF lenses, and I thought I'd put it to a simple chart test. Run through the apertures, see how contrast & sharpness hold up, etc. Then, for grins, I decided to put it up against the stock lens, same aperture, same (basic) focal length. And then, I dug out my old $40 Zeiss Jena M42 screwmount lens, and put it on there too.
Tests were to see how the lens resolves at various f-stops, both in stills and movie mode.
Prediction: there won't be much if any difference among any of them in movie mode, but there should be a noticeable sharpness difference in the order of ZF > CZJ > stock.
Actual results? Well... hmmm.
First, lens properties at various apertures, in stills mode, as compared to their own selves (not comparing to each other).
ZF: Sharpness is pretty decent throughout the range, up until f/22. F/22 goes too far and sharpness really falls off. Looks best from 5.6 thru 11.
CZJ: flat contrast, but reasonable sharpness, at 2.4. Nicely sharp and contrasty at 5.6. Some aliasing present, implying that it's sharper than the sensor can resolve. Contrastier, and perhaps slightly less resolving, so that the chart actually looks better with no aliasing at f/11. At f/16 it's not as good, definitely softer and flatter. At f/22 it goes to pot.
Stock lens: looks like hell at 5.6. I mean, to be fair, it's still resolving maybe 1100 lines, but compared to the Zeiss, it's getting beaten like a US soccer team. But, I'm not supposed to be comparing across lenses yet, so ... at 5.6, kind of soft & fuzzy. At f/11, it's night and day. Way, way better than 5.6. Crispy sharp, with aliasing even showing up. This lens likes f/8 to f/11. At 16, we're headed back the other way. Softer and flatter, than at f/11, but still miles better than f/5.6. And, no aliasing -- so it might even be rendering "better" images at f/11, but they won't have that extra-crisp "pop." At f/22, it's the same noisy/muddy mess that the other lenses turn into.
Which tells me that we're probably seeing major diffraction ruining the image at f/22. All three lenses perform similarly at f/22. My recommendation for still shooters is avoid f/22 with *any* lens, on a GH1. Just don't go there. You can get good results at f/16, but f/22 is too far and diffraction softens the images.
Okay, so now that we know how the lenses perform in and of themselves, how do they compare to each other?
At f/2.4, the Zeiss ZF looks, to my eye, not as nice as the 30-year-old Carl Zeiss Jena lens, in terms of chromatic aberration -- there's a little bit more in the ZF as opposed to the slightly cleaner CZJ. The resolving power in the center is about the same, and they're both beating the pants off the stock lens (at 5.6!) but the ZF seems to have some purple chromatic aberration tint to it, that the CZJ doesn't. The corners are an odd situation -- the ZF slays on the left, the CZJ wins on the right. I don't think the camera moved at all between the setups, so ... that's odd. Overall, score a win for the CZJ for f/2.4. The stock lens isn't even in this game, of course, because it can't open that wide.
At f/5.6, the two zeiss lenses are near identical, and both are so laughably superior to the stock lens that it seems seppoku would be the only way out for the poor 14-140. Between the ZF and the CZJ, I'd say the CZJ has a whisper more detail, but it's so close as to be not really even relevant. In the corners, the ZF is clearly sharper and contrastier, putting out so much detail the GH1 starts aliasing. So for f/5.6, the ZF wins, CZJ is a decently close second, and the stock is a distant third.
At f/11 -- same story between the Zeiss lenses. The ZF may have a tiny edge, but it's splitting hairs to find it. They're basically identical. The stock lens? It looks just as good! By f/11 the stock lens has come to play. It's sharp enough to be causing aliasing too; all three lenses are outperforming what the GH1's chip can handle. This is pretty much a three-way tie, at f/11.
At f/16 -- the ZF is maybe two hairs ahead of the CZJ at this point. It's still very close. They're both a decent edge ahead of the stock lens. The stock is still competing, not bad at all, but a small edge goes to the Zeiss brothers. ZF wins, CZJ is a close second, and stock is a close third.
At f/22 -- The ZF is definitely beating the CZJ. Not night and day, but by a respectable amount. The stock lens doesn't embarrass itself, it puts in an okay showing for sharpness. But, the zeiss lenses are showing a little oranghe chromatic aberration, and the stock isn't. Overall, a three-way tie.
So -- that's how they performed in stills comparison. I expected the Zeiss lenses to beat the stock, and they did, and oh boy how they did. What I didn't expect is how well the CZJ did! Not bad at all for a 30-year-old $40 lens, as compared to its brand-new $1,000 counterpart!
The ZF is still nicer, slicker, and better; after Duclos gets through with it it should be a reasonable approximation of a cine lens. And it's a half-stop faster. And it has nicer focus travel and build quality and on and on... But for bang-for-the-buck purposes, the Carl Zeiss Jena 35mm/f2.4 really acquitted itself very well!
(note: it's tough to remember everything when doing one of these comparos, and the thing I forgot this time was to re-white-balance between each lens change. As such, to remove unfair color cast issues out of the comparison, I used the auto-adjust features of PhotoShop).
Tests were to see how the lens resolves at various f-stops, both in stills and movie mode.
Prediction: there won't be much if any difference among any of them in movie mode, but there should be a noticeable sharpness difference in the order of ZF > CZJ > stock.
Actual results? Well... hmmm.
First, lens properties at various apertures, in stills mode, as compared to their own selves (not comparing to each other).
ZF: Sharpness is pretty decent throughout the range, up until f/22. F/22 goes too far and sharpness really falls off. Looks best from 5.6 thru 11.
CZJ: flat contrast, but reasonable sharpness, at 2.4. Nicely sharp and contrasty at 5.6. Some aliasing present, implying that it's sharper than the sensor can resolve. Contrastier, and perhaps slightly less resolving, so that the chart actually looks better with no aliasing at f/11. At f/16 it's not as good, definitely softer and flatter. At f/22 it goes to pot.
Stock lens: looks like hell at 5.6. I mean, to be fair, it's still resolving maybe 1100 lines, but compared to the Zeiss, it's getting beaten like a US soccer team. But, I'm not supposed to be comparing across lenses yet, so ... at 5.6, kind of soft & fuzzy. At f/11, it's night and day. Way, way better than 5.6. Crispy sharp, with aliasing even showing up. This lens likes f/8 to f/11. At 16, we're headed back the other way. Softer and flatter, than at f/11, but still miles better than f/5.6. And, no aliasing -- so it might even be rendering "better" images at f/11, but they won't have that extra-crisp "pop." At f/22, it's the same noisy/muddy mess that the other lenses turn into.
Which tells me that we're probably seeing major diffraction ruining the image at f/22. All three lenses perform similarly at f/22. My recommendation for still shooters is avoid f/22 with *any* lens, on a GH1. Just don't go there. You can get good results at f/16, but f/22 is too far and diffraction softens the images.
Okay, so now that we know how the lenses perform in and of themselves, how do they compare to each other?
At f/2.4, the Zeiss ZF looks, to my eye, not as nice as the 30-year-old Carl Zeiss Jena lens, in terms of chromatic aberration -- there's a little bit more in the ZF as opposed to the slightly cleaner CZJ. The resolving power in the center is about the same, and they're both beating the pants off the stock lens (at 5.6!) but the ZF seems to have some purple chromatic aberration tint to it, that the CZJ doesn't. The corners are an odd situation -- the ZF slays on the left, the CZJ wins on the right. I don't think the camera moved at all between the setups, so ... that's odd. Overall, score a win for the CZJ for f/2.4. The stock lens isn't even in this game, of course, because it can't open that wide.
At f/5.6, the two zeiss lenses are near identical, and both are so laughably superior to the stock lens that it seems seppoku would be the only way out for the poor 14-140. Between the ZF and the CZJ, I'd say the CZJ has a whisper more detail, but it's so close as to be not really even relevant. In the corners, the ZF is clearly sharper and contrastier, putting out so much detail the GH1 starts aliasing. So for f/5.6, the ZF wins, CZJ is a decently close second, and the stock is a distant third.
At f/11 -- same story between the Zeiss lenses. The ZF may have a tiny edge, but it's splitting hairs to find it. They're basically identical. The stock lens? It looks just as good! By f/11 the stock lens has come to play. It's sharp enough to be causing aliasing too; all three lenses are outperforming what the GH1's chip can handle. This is pretty much a three-way tie, at f/11.
At f/16 -- the ZF is maybe two hairs ahead of the CZJ at this point. It's still very close. They're both a decent edge ahead of the stock lens. The stock is still competing, not bad at all, but a small edge goes to the Zeiss brothers. ZF wins, CZJ is a close second, and stock is a close third.
At f/22 -- The ZF is definitely beating the CZJ. Not night and day, but by a respectable amount. The stock lens doesn't embarrass itself, it puts in an okay showing for sharpness. But, the zeiss lenses are showing a little oranghe chromatic aberration, and the stock isn't. Overall, a three-way tie.
So -- that's how they performed in stills comparison. I expected the Zeiss lenses to beat the stock, and they did, and oh boy how they did. What I didn't expect is how well the CZJ did! Not bad at all for a 30-year-old $40 lens, as compared to its brand-new $1,000 counterpart!
The ZF is still nicer, slicker, and better; after Duclos gets through with it it should be a reasonable approximation of a cine lens. And it's a half-stop faster. And it has nicer focus travel and build quality and on and on... But for bang-for-the-buck purposes, the Carl Zeiss Jena 35mm/f2.4 really acquitted itself very well!
(note: it's tough to remember everything when doing one of these comparos, and the thing I forgot this time was to re-white-balance between each lens change. As such, to remove unfair color cast issues out of the comparison, I used the auto-adjust features of PhotoShop).
