Uncategorized | Terence S Jones - a guy with a camera

This is just a brief post on focusing the Nokton lens on a Nex body and shutter priority for short exposure times. I made the experience that for example focussing on infinity depends on the aperture and is somewhat shifted. Just putting the focus mark on infinity does not fly – there is some overfocusing. This is not the classical focus shift however. So here are a few numbers to keep in mind:

Focusing on infinity:

f/1.4 -> move focus marker on left o of the infinity mark
f/2.8 -> move right depth of field marker for f/2.8 on left o of the infinity mark
f/8 -> move right depth of field marker for f/5.6 on left o of the infinity mark

Also what works great for street photography is f/8 and putting the focus marker on 2.5m.

Another thing that annoyed me is that in medium light situation the body tends to keep iso low as long as the exposure time is at least 1/30 which can easily lead to blurry images. However I found a great trick to circumvent this -> shutter priority. At first this seems to be pointless as the aperture cannot be changed by the camera. But that is exactly the point: the camera regulates the exposure value by adjusting the ISO sensitivity. So more precisely, when it is extremely light, use your favorite aperture. As it is light enough, there is no need to worry about too long exposure times. Similarly, if it is too dark there is nothing to worry at all as the exposure time will be long anyways. However in medium light situation, go to shutter priority and choose e.g., 1/150. As the camera cannot adjust the aperture it adjust the ISO setting to maintain the short exposure time.

As promised earlier, here is my review of the Sony NEX-3 together with the Cosina Voigtländer Nokton Classic 35mm f/1.4 lens. I will not provide yet another review of the lens or the camera alone – here are a few excellent reviews of either of those separately:

: Nokton Classic on Sony NEX-5 by yellownurbs (I still have to take some of the NEX-3 with the Nokton Classic)

I initially got the Sony NEX-3 with the E 16mm F2.8 Pancake lens but I had to realize pretty fast that this lens wasn’t doing it for me. On the Sony body with a crop factor of 1.5 the 16mm is roughly a 24mm equivalent. While this focal length might be nice for some architectural shots or landscapes/scenery it didn’t live up to what I would consider an everyday lens. On the other hand, I didn’t want to get a heavy zoom lens which would render the size advantage of the NEX nil. I wanted to have a combination that was good for carrying around almost everyday and that would still provide a superior image quality. It should especially provide me with a decent solution when I cannot carry around my other gear which is somewhat heavy. That’s how I eventually ended up with the Cosina Voigtländer Nokton Classic 35mm f/1.4. I got both, the lens and the adapter for the NEX, from Photovillage in New York at a price tag of roughly $850 – I opted for the Voigtländer adapter which is a bit pricy but I read about some problems with other adapters so I decided to go for the original. As you can see in the picture above, the sony nex body + nokton classic is still a pretty compact solution. The picture shows the Nokton Classic on a NEX-5 body! I am travelling right now, solely with the NEX-3, so that I wasn’t able to take a picture of it yet. However the NEX-3 + Nokton Classic basically looks the same. The body is even a bit smaller.

Let me first give you a list of advantages and disadvantages and then I will address the points in the following. In a nutshell the nokton classic is a fully manual lens (manual focus / manual aperture) with a slightly classic look put on steroids on the sony nex body.

Advantages:

The camera + lens is small and quite lightweight – a huge advantage when travelling compared to my 7D with, say the 24-70 f/2.8 lens.
The lens is very fast: f/1.4 together with the large APS-C sensor (which are widely used in DSLRS) provides superior image quality with low noise in low light situations.
The lens is 35mm which roughly is a 56mm equivalent. This is a good focal length for street photography and day to day use. It can be even used for some portraits, although however the focal length is a bit short for this. A few examples follow below.
The NEX provides a manual focus assistent which makes manual focussing a bit easier.
The lens is a prime lens. I personally prefer this over zoom lenses as it provides a completely different feel.
The lens is very sharp from f/2.8 on reaching its sweet spot at about f/8.
The rendering of the combination is very nice: great colors, great contrast.

Disadvantages:

The lens is a manual focus lens. Sometimes when you want to take a snap shot this can be a problem. Especially in the beginning I missed focus a lot. However I have to say that once gotten used to that you will take pictures more slowly leading to an overall different experience.
The lens is a bit soft when shot wide open down to f/2.5
The nex body is a bit too menu-driven for my personal taste. I would have wished for some type of quick access button as my 7D has to access essential functions.
Lens flare when shooting into light and sometimes purple fringe.
Lens also has some optical distortions such as barrel distortion. This gives the images a more classical look. It depends on you whether you like this.

I have been using this combination for roughly 3 weeks now. So what can I say? The overall package is pretty amazing. The image quality is very good and you have tons of creative freedom. The most challenging part when using the lens day to day is the focusing. It is not that challenging however. Also it has a manual aperture so that the only “automatic” mode that you have is aperture priority (A). What works great for me is setting the aperture to f/8 for general purpose shooting if light permits. Then you can use zone focusing for street photography etc., and the depth of field somewhat large already. Keep in mind that the lens is attached to a APS-C sensor so that in terms of depth of field you roughly lose one stop, i.e., at f/8 you need to use the f/5.6 depth of field indicator. The lens seems to be sharpest at f/8 on the NEX body. What can be a bit annoying sometimes is that the camera tends to reduce the ISO as long as the shutter speed is at least 1/30. For moving objects this can be too low. Also as the lens is a 56mm equivalent, camera shake can blur images. What I found helpful here is to manually choose the ISO setting to get the desired speed. In low light situations or for portraits you can go up to f/2.8 and you will still have extreme sharpness and, for portraits, a shallow depth of field (see below). I try to avoid going beyond f/2.8 because the lens gets a bit softer (although not too much) and it is considerably harder to focus because of the extremely shallow depth of field – your subject moves a tat and it is out of focus. However, when needed and there is enough time for proper focussing (or you are taking a picture of something that doesn’t move), the f/1.4 provides you with two extra stops (over f/2.8) in extremely low light situations and together with the ISO1600 performance of the NEX body, which is very good, you might be able to take a few good shots where others might fall short.

I cannot say anything about the JPEG quality of the camera as I am shooting raw only. Together with software such as Aperture or Adobe Lightroom (my favorite) this provides you with superior control (white balance, sharpness, etc.) over the final image: you can do some more major adjustments if need be and otherwise you can define some standard presets for general purpose processing.

Here are a few shots so that you can see what the combination can do for you.

Both of the above pictures were taken in low light at f/2.8 with fill flash. The next four were taken a couple of days ago in the Bulgaria close to Bansko at f/8 with available light only. I did some minor adjustments in lightroom to change the feel.