Steve Spencer
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 p.1 #2 · Laowa 15mm f2 for Z mount "fun" | |
GroovyGeek wrote:
I have been looking for a lens for the occasional night/milky way shot that I do that a) does not weigh a ton b) does not break the bank c) has reasonable performance and d) preferably does not require adapaters on my Z6. The Laowa 15mm f2 "zero D" seemed to fit the bill based on the available reviews, so when one became available for $620 in "like new" condition on Adorama I decided to take the plunge.
Lens arrived today, and I would say that unlike B&H, Adorama has a fairly liberal interpreation of what "like new" means. The lens had visible smudges on the plastic surrounding the front element. But that is just a side issue for the purpose of this discussion.
While shooting it on a tripod side by side with the 14-30/f4, I noticed that at equivalent f-stop the Laowa would meter differently in A mode, and under equivalent settings in M mode it would produce darker images. Which caused me to run additional tests. On a tripod, in A mode, under fixed artifical lighting conditions I would simply record the metered shutter speeds.
The 14-30Z behaved exactly like you would expect. In the f/4-f/22 range at 1 stop increments the metered speeds were
f/4->f/22: 1/20, 1/10, 1/5, 1/2.5, 1/1.3, 1.6"
f22->f4: 1.6", 1/1.3, 1/2.5, 1/5, 1/10, 1/20
The Laowa not so much:
f/2.8->f22: 1/40, 1/20, 1/13, 1/5, 1/3, 1/1.6, 1"
f22-> f2.8: 1", 1", 1/2, 1/5, 1/10, 1/20, 1/40
The aperture ring was in "click" mode. It is immediately obvious that the calibration is not correct, and there is significant backlash/hystersis between the up and down series. I repeated the test a couple of times and it was repeatable. As soon as the aperture was decreased above f/5.6 the increments were not integer steps of 1/2, and the return sweep was offset from the forward one.
In addition, the lens would meter in A and S modes, but not in M mode. Not sure if I would blame Laowa for that one, it may be something due to Nikon software, but it is a hassle to deal with either way.
Have not done detailed comparisons of IQ yet but it seems about what you would expect relative to the 14-30. Not as good contrast, not as good sharpness, slightly muddy look in the corners, even at f/16. Given that this lens lists for 65% of the Nikon the latter is not too surprising. I did not note any obvious decentering issues, though I have not looked too carefully.
These results are disappointing. I was hoping that the lens would be good enough to keep. I will play with it through the weekend, may actually do some milky way photography on Thu when the moon will rise under the full arc of the MW at 4:30am. But it is very likely going back to Adorama. Seems like I will need to spend more money. Alas, my options in native Z mount will be limited for the foreseable future. I just don't see myself spending $2.5k (or more) on the 14-24/2.8S. May have to wait for the Rokinon 14mm SP to come up used at a good price and shoot it adapted. By all accounts it is notably better than the Laowa....Show more →
Groovy Geek this is a well know problem with adapters on the Z cameras. Above f/5.6 you either have to have the camera set to wide open (in this case f/2), or use expose compensation if you set the camera to the aperture on the lens. It is caused because the camera is expecting that the lens is metering at f/5.6 but will stop down when taking the picture. This is not what you are doing, however, so you will either have to adjust for it, or set the camera at f/2 in which case it will just think the ambient light is darker than it really is but it will still meter properly.
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