What Makes a Good Lens? Things to Consider When Shopping for a New Lens
In the last few months, there has been an up trend in premium lenses, cinema lenses and the interest in super high grade lenses like the Zeiss Otus. Sigma have seemingly noted this and with a new Global Vision mantra, they have it all to prove, and are headed in the right direction it seems. When shopping for a new lens, we have to be able to think about more than just focal length. Just as the highly anticipated Sigma 50mm is about to hit the market, we have a look at what makes a good lens and what we should be looking for when shopping for one.
[And check out our Head2Head comparison on the SIGMA 50MM F/1.4 DG HSM ART VS. CANON 50MM F/1.2 here]
Sigma Speaks Out
I recently made the choice to invest some money into my Nikon lens collection. To ensure money is wisely spent, it seemed right to invest in lenses that were not developed in a pre-digital era. I found that Sigma had mentioned that the new range of Global Vision lenses are high megapixel optimized. We contacted Sigma and asked what they meant by this:
Can you explain the differences in design for the new range of lenses? What makes them specially designed for high megapixel cameras ?
We consider the lenses as our essential asset and never stop thinking of ways to create lenses that ensure photographers get the pictures they desire and to use for many years, even if they change to different camera bodies. Customers always need better optics. In order to create high-resolution images, lenses are of almost equal importance as the sensor. We have been improving our quality control over the years, and we developed our own MTF measurement tool which uses our Foveon sensor. The sensor has very high resolution so it can measure our lens performance at a very high frequency. We now use that system in the production of all new lenses.
Did the change in direction for Sigma come from an internal process or from the demand for quality from the consumer ?
Sigma has always been striving to provide excellent quality products and we feel that customers also believe in us to continue doing so. Thus, our idea consists of two parts.
We always go back to the essence of photography and listen to the requests of photographers to ensure we produce photographer-centered products.
However, we can tell that the new vision and direction for Sigma came from an internal process. Sigma has been on the path of a unique direction and vision with our philosophy and value which generated of our own accord.
Would Sigma ever make a super premium lens like the Otus ? Maybe a high end cinema lens similar to the Canon EOS range ? The 35mm lens marked a new era for Sigma, do you expect this continue or do you think other manufacturers are also lifting the standard across the board with quality?
Sigma’s product development or specifications are not determined based on the expected competition from other manufacturers.
We ensure that we develop each product with the best optical design according to the concept of each new product lines A/C/S.
We believe that delivering the best and satisfying quality products to our customers is the most important thing. Therefore, we will challenge ourselves and continue to strive for manufacturing excellent products in the future as well.
It does seem that Sigma is moving forward, but with a eye firmly fixed on consumer demand and looking to follow the trend. The MTF testing process Sigma uses is super fast and does allow them to test every single lens, meaning they can produce a lens with a finer tolerance, yet ensure super high quality out the factory gate. The composite body of the new generations has better thermodynamic properties allowing for even finer optical quality & build. When you combine this with long history of innovation, you get things like the 35mm A and the brand new 50mm A. Recently I have been testing the 24-105 f4 A from Sigma and it is also very impressive.
The 24-105mm is very good, however, there is truth to the idea that prime lenses are optically better than zooms. Every so often, the idea that zooms are catching up comes up to the topic of discussion, but the difference must be closer than ever. So, just how close are the days where a variable zoom can stand to the sharpness of a prime lens? Not quite yet from these tests, but I have to say that the zoom did far better than I thought it would. I would love to hear from people who used to stick to primes, but who are now happy to shoot with variable zooms.
Things to Look at When Considering a New Lens
When it comes to choosing which lenses to acquire there are a few things to look at.
What you are planning to shoot, what camera you shoot with and of course, the budget are the main components when considering a new lens purchase. This usually determines the focal length and f-stop to go for. After that, these are the other things I look for (in no particular order):
- Micro contrast
- Shape of bokeh
- Overall sharpness
- Chromatic aberration
- Over all build quality
- Smooth focus movements
- Metal contacts
- Filter size
- Focus speed
These days the I also take into account how well the lens would work shooting video, too. Good finger placements and smooth barrel movements have also risen on the list of important features.
Branding and the idea of a having to buy Nikon because of my Nikon D800 or Fujinon due to having an X-Pro is something of the past these days. Sigma proving that they they are a company to contend with and are taking away business from people who used to write them off as being substandard to Canon or Nikon, let alone Zeiss or anther high end lens designer.
What’s In My Camera Bag
- Sigma 35mm f/1.4 A
- Sigma 24-105mm f/4
- Sigma 105mm f/2.8
- Sigma 120-300mm f2.8
- Sigma 50mm f/1.4 A (coming very soon)
I would love to add some manual lenses like the Zeiss 55, but the auto focus is a deal breaker for me.
David Newton – On Canon and What Makes a Good Lens
Canon has some amazing new gear and advancements with focus movements and image stabilization which make them great for budget film makers. To balance this article, since Canon does not make Nikon or Fuji lenses, we asked David Newton who is a writer/ teacher who works closely with the Canon EOS network what he thinks about what makes a good lens.
As most photographers are, I too am a bit of a lens snob. After all, it’s the lens that projects the image back onto the sensor, so a poor lens will always lead to poor image quality. However, while my bag is usually stocked with the L-series lenses, there are times when I’ll look further ‘down’ the range. A good example of this is the EF40mm f/2.8 STM lens. This is a tiny ‘pancake’ style lens that uses a different type of focus motor – the Stepper Motor (hence the STM in the name). The stepper motor works a little differently to the more normally encountered UltraSonic or USM focus drive in that it has been designed to work especially well with the Movie Servo AF focus found on several EOS models.
If you’ve tried auto focusing in movie mode (on almost anything except the EOS 70D), you’ll have discovered that it is slow and jumpy at best. However, the STM motor helps to overcome this by providing much smoother focusing that is also, like a USM motor, exceptionally quiet too.
The EF40mm lens is not the only lens to feature an STM focus motor. In fact, several more low-cost lenses do too, for example the EF-S 18-135mm f/3.5-5.6 IS STM and the EF-M 18-55mm f/3.5-5.6 IS STM, one for APS-C sensor camera and one for the EOS M compact system camera. In total, there are currently six lenses within the EF, EF-S and EF-M ranges to incorporate the technology all of which are at the more ‘budget’ end of the lens range, showing that Canon are not just focused (excuse the pun!) on the high-end users, but are actively trying to improve the shooting experience and results of users with less background knowledge. “
You can find out more about David Newton here – http://www.photopositive.co.uk/
Glynn Lavender on Why He Only Shoots With Tamron
It is also worth noting that companies like Tamron are starting to raise the game also. Glynn Lavender (teacher and trainer for www.creativephotoworkshops.com.au from Melbourne Australia ) is currently sponsored by Tamron. We asked Glynn why he chooses to only shoot Tamron.
Why Tamron? Half the reason is to battle the misconception that the only way you can be a good photographer is to have the most expensive gear. To me, it is about having the right tool and not the most expensive tool. After all, if you give me the best saucepan in the world it won’t make me a better cook. But give me a pretty darn good saucepan and then give me the knowledge on how to get the most out of it and I’m in a lot better world.
I think Tamron’s focus (excuse the pun) is ‘alternatives.’ They want to give photographers an alternative. They are not trying to replicate the whole range made by the majors, but picking out selective high volume and working hard to produce great lenses at affordable prices in those ranges. Sigma, and a few other makers look to be targeting the slightly more niche market and producing quality alternatives in prime lenses as well as covering the major zoom markets.
It is not an unknown secret that photography is an expensive game to be in, even more so if you are a working professional. Investing in the right areas such as the right lens can be tough, but will let you get the best out of all your other investments. Money in glass is always a priority for me over other areas.
What lens do you have your eye on next? Comment below.