So I received a Bower (Samyang) 8mm Fisheye lens (DX/Crop/APS-C) as a gift on Saturday, Nov 14. I haven't played with it too much, but I thought I would share a bit here about my initial impressions and a few quick sample images.
Size and Weight
This lens is small - almost the same size as the Nikkor 50mm 1.8D - with the obvious exception of the large bulbous front element. It comes in at just under a pound (around 391g). It's weighty due to that large chunk of glass hanging out there on the front end.
Mount (f-mount)
It mounts normally, though it seems a bit tight compared to my other lenses. I guess it's good that it's tight, but it could be a fraction of a millimeter looser.
Manual Everything - mostly focus.
Yup - manual everything... mostly. Manual focus only - though with it being such a wide lens, it's hard to not get something in focus. The focus scale goes from 1 to 5 feet, then infinity. There is a focus confirmation within the viewfinder, but it's pretty loosy-goosey. Sitting here typing this and trying to test focus scale - My keyboard is about 12-14" away from my sensor, but the scale on the lens barrel (according to the focus confirm icon) says that it's 2' away, and remains in focus up to infinity. Here are two shots showing an attempted focus using the 2' marker, followed by the infinity marker. The focus confirm icon was lit in both cases.
Aperture is also fully manual on this lens, with no way of controlling aperture from the camera body. It clicks at each stop and half-stop, but not a super hard click like some lenses.
The lens does work, however, in Aperture priority mode on my D610. Since I can control the aperture, and this is fed back to the body, it can still make calculations for exposure. What I've found, however - at least indoors, is that since this lens capture 180º corner to corner FOV (DX crop mode), the overall exposure can be quite wrong - even in spot or center weighted metering. I had to increase exposure compensation 1 2/3 stops to get a decent exposure.
The lens does work, however, in Aperture priority mode on my D610. Since I can control the aperture, and this is fed back to the body, it can still make calculations for exposure. What I've found, however - at least indoors, is that since this lens capture 180º corner to corner FOV (DX crop mode), the overall exposure can be quite wrong - even in spot or center weighted metering. I had to increase exposure compensation 1 2/3 stops to get a decent exposure.
Optics - Performance, Sharpness, etc.
Well, I haven't had enough playtime with this lens to give a real judgement here. But so far, it has room for improvement. That said - I've only tried f/3.5. My main use for this lens would be for stars/astrophotography. So, I went on to my patio to capture a few stars. I live in the city, where we have some nasty high power LED street lights - light pollution is high, but at least white instead of orange. The flare on this lens is quite hideous - I will need to do some further testing out in the fields away from the lights. However - I live in Southern Alberta (Lethbridge), where agriculture is predominent. That means farmhouses everywhere, with several lights per house. In order to capture the horizon with such a wide 180º lens, I will almost always have farm lights in my scenes. Hopefully I can avoid flares.
This lens is design for APS-C sensors, I have a full frame. The following image shows the full sensor capture (including the built-in lens hood):
15sec, ISO 2000, F/3.5, focus set at infinity.
There is some coma and slight CA, but again, hard to judge accurately with my quick setup on the patio. Will need further testing.
One of the fun things to do with ultra-wide angle lenses is perspective stretching, and this one sure works well for that. Here's a sample of my youngest daughter (hard to focus on her at the best of times, let alone with MF). This was at a very close distance - only a few inches from the front of the lens. 1/400th, ISO 800.
One of the fun things to do with ultra-wide angle lenses is perspective stretching, and this one sure works well for that. Here's a sample of my youngest daughter (hard to focus on her at the best of times, let alone with MF). This was at a very close distance - only a few inches from the front of the lens. 1/400th, ISO 800.
Video performance
Not much to say here - it works well, gives similar output as a GoPro ultra-wide but with DSLR controls. More to come.
Conclusions
Well, so far, so good. It will be a fun lens, and should give some impressive views of the night sky (my main goal). The few drawbacks (flare and coma) hopefully will not distract from the overall wide view, especially for timelapses. I will need to do more testing at tighter apertures to see what I can find in terms of sharp sweetspots, and night sky performance.
Thanks for reading - please comment and share!!
Thanks for reading - please comment and share!!