Sony Nex 7 Rolling Review: Part III – Paired with the Voigtlander 15mm F4.5 Heliar

The main reason I bought the Sony NEX 7 was to use with my Leica M kit, even though many reviews that said the NEX 7 sensor has a serious flaw that makes it unsuitable for use with wide angle rangefinder lenses. The NEX 7 sensor has a layer of micro-lenses, these micro-lenses focus the light hitting them from the lens onto the photo-receptor sites of the sensor. On the NEX 7 they’re built with SLR type lenses in mind that sit much farther from the sensor than rangefinder lenses, the light coming from SLR type lenses striking the sensor at nearer to perpendicular angles. Rangefinder lenses, especially wide angle ones, have rear elements that extend much closer to the sensor, causing the light they focus to hit the sensor at much more oblique angles the further they strike from the center. The micro lenses of the NEX 7 sensor can’t seem to handle light hitting them at such extreme angles which leads to color shifting and lowered sharpness at the edges and corners. I won’t dispute this makes the NEX 7 less than optimal when paired with such lenses, the question is: “Is less than optimal still good enough to take good pictures?” The first lens I’ll be taking a look at with this in mind is one of my favourites, the Voigtlander 15mm f4.5 Heliar.

I’ve been using this lens with great success on my Leica film cameras for years, later it became one of my most used lenses on the Sony NEX 3 as well. On the NEX 3 it performed very well, with very good corner sharpness and color fidelity. I was kind of worried when I heard it didn’t fare so well on the NEX 7. After trying it out for a few weeks, I admit, the NEX 7 definitely had an issue with wide angle rangefinder lenses. I do notice some loss of sharpness and magenta color cast in the corners with the Voigtlander 15mm, especially wide open, by f8 it’s much better.

If you’re a landscape photographer who needs perfect sharpness edge to edge or just happen to like looking at pictures of brick walls at 100% magnification, this may not be the lens for you. On the other hand, if you already have one, it’s definitely worth the price of an adapter to be able to use it on the NEX 7. It’s still wonderfully sharp over the majority of the frame on the NEX and has very little barrel distortion. It’s nice and small, making the camera nearly pocketable and is wonderful for street photography being roughly a 24mm lens on the NEX 7.

In technical tests, the corner performance might scare some people off, but I prefer to let real world images be the judge of a lens. A lens is more than sharpness of its optics, the small size and discreteness make it a perfect lens for unobtrusive shooting and it’s got a great depth of field scale, something you won’t find on any of the native E-Mount lenses. If you’re shooting for black and white, the magenta cast is not really an issue. Even in color, I’ve found some creative ways to process my images, using the color cast to add character. If it really bothers you, there’s a free program called CornerFix that does a very good job of correcting the issue.

I’m still a bit disappointed the NEX 7 didn’t handle this lens better, but the combination still makes stunning images. Sharpness isn’t everything and the NEX 7 has enough going for it that I’m willing to make the compromise. If you where expecting 100% crops of brick walls in this review, I’m sorry, I don’t have the time or the energy to pixel peep anymore. Been there, done that, almost went blind and broke trying to satisfy the pixel gods. The pair produce really nice black and white images, and with the right processing the color images call to mind the charm and nostalgia of some of the great color films of the 60’s and 70’s. If Lens Baby came out with a lens that boasted retro color cast, blurry corners, it would be a hit, but do it accidentally and it’s a flaw… oh well. Like I said, it may not be the right tool for every photographer, but it’s still one of my go to lenses on the NEX 7.

PS – None of the images in this post (or any of my CV 15mm + Sony NEX 7 images on my Flickr as of this post) have any local color or sharpness correction done to mitigate any blurring or color cast this combo creates. Any sharpening or color manipulations have been global, across the whole image, so you be the judge as to whether this combo is capable of creating good images in the real world.

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Vijay Ramani

Thank you so much for this review! I’ve just now ordered the CV 15mm and this review helps put my mind at ease about all the color cast issues people complain about. Your images are all stunning! If possible, please share your post-processing steps that helps you get that 60s-70s film look. I love it, but just don’t know how to get that look.

Thanks again!
http://jbhildebrand.com Jesse Hildebrand

Glad you found it useful! As for my post-processing, I may cover that in an upcoming post… but for now I’ll just say: “Play around with split toning in Adobe Camera Raw”
Vijay Ramani

Hi again. I just got back from a trip to Hawaii where I put the CV 15mm to use with my NEX-7. The color cast issue exists and is very obvious in my images. I managed to quickly fix it in LR though. I just turned down the “Purple” saturation to 0 and the problem was solved. I didn’t have any noticeable purple in the rest of my image so this change didn’t affect the photo negatively.
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Jeffrey Ubando

I’ve been looking at your images on flickr and was just in awe on how great your street photographs are. Had to visit your site and give you one of those virtual High 5′s. I was hesitating getting the 15mm until your review. I’m not a big worry wart on every little pixel. Its just fun capturing great moments. Just curious if you don’t mind answering; The photos seem very candid and you have a lot of images what seems to be at the same area. Are you sneaking a pic or your down and dirty and obvious to the people you are taking the picture?
http://jbhildebrand.com Jesse Hildebrand

Thanks Jeffrey, glad you’re liking my street work. Yeah, I try to keep my work as candid as possible, but I don’t really make any attempt to be sneaky. I’ll walk around or stand with my camera around my neck, finger on the trigger and shoot from the hip. I don’t make any attempt to hide what I’m doing, but I don’t advertise either. If someone notices me taking a picture I’ll smile and say thanks. Give my Shooting From The Hip posts a look for more info:

http://jbhildebrand.com/2012/street/street-photography-tutorial-5-shooting-from-the-hip/
Steven

I have the Olympus OMD and I use the 15mm Heliar on it as well. The OMD does not suffer from the magenta effect but it does have the corner blur issue. The OMD sensor also uses the micro lenses and this causes corner blur with wide angle lenses designed for rangefinders.

But OMD also has corner blur on short focal length SLR lenses too. If I try to use my Contax Yashica 28mm on the OMD the corners will still have blur even though this is an SLR lens. Much less blur
mind you than the 15mm Heliar, but still some blur. Once you get a lens on the OMD of 35mm or longer the blur goes away.

I am considering a Nex 7 because the sensor is even more packed with pixels than the OMD and should have a much higher resolution image at low ISO. Sadly Nex 7 has much noisier higher ISO than the OMD. But the OMD sensor and the Nex 7 share the Sony look which I like very much. The Nex 7 would be perfect for my Lecia M Zeiss Sonnar f1.5. It would be a 75mm portrait and street lens on the Nex 7 and have all the magic of the Sonnar.

Here are some examples of pics I took with the OMD using the Heliar and other Lecia M mount
lenses: http://500px.com/stevennorquist