Manual Focus Lenses Forum

Henry Fisher · Joined: 11 Oct 2008 Posts: 20 Location: USA

Hello Forum.

I would like to open a discussion about the use of older optics in front of modern digital sensors. The reason is that I am reading conflicting information in this respect, and I would like it sorted out by the Membership here who may have experience in this respect.

More than a few have said that digital sensors are reflective, and as such, they require optics that have improved anti-reflective coatings. Some have said that superior coatings designed to address this issue are a key ingredient it what it is that constitutes so called "digital lenses."

Recently, I read a thread on nikonians.org wherein a gentleman said that he did not recommend Nikon's series E lenses for digital sensors because they were only "single coated."

Are you using older lenses with single coatings or with no coatings with your dSLR? Are you pleased with their technical performance? Do you have problems with flare or internal reflections which are leading you towards upgrading to only "digital" lenses?

I am particularly interested inasmuch as I intend to us a lot of old Nikon and other F mount manual focusing glass on a D700. So far, I am not seeing the problem. One of my lenses is a 50mm f1.8 Series E, of the sort that the nikonians.org gent "does not recommend." It seems to have no problem whatsoever, as far as I can tell. What am I missing in this analysis? The pictures look good to me.

Are there special limitations or precautions one should consider when one is using old glass on new digi bodies?

Thanks for reading this, and for the courtesy of your response.

Happy day.

Smile

Spotmatic · Joined: 18 Aug 2008 Posts: 4045 Location: Netherlands

I can only tell about my own experiences, and I have used several lenses from 1896 up to today. Most of my lenses are single-coated and some of them not even coated, and I'm not seeing any problems either. Of course, most of my uncoated prewar lenses are low contrast because of light shattering in the lens, but nothing that can't be corrected in PP.

A good modern example is my Sigma 500mm f/4.5 APO EX. Apparently there's an updated version available with "DG" in its name because it has a "special" digital coating. Well, my shots with the non-DG lens are nothing short of superb, so I don't feel the urge to upgrade just for a "better" coating.

Mind you: I don't say that the problem does not exist, just that I don't see it. Let's reserve this discussion for people who never take photographs, but only talk about it Wink

cooltouch · Joined: 15 Jan 2009 Posts: 9096 Location: Houston, Texas

Well, bearing in mind that I'm commenting based on my own experiences, and to some extent on what I've read, here's my take on things:

Yes, "digital lenses" have coatings as well as internal baffling in some cases designed to deal with the stray reflections that can degrade the image. But I suspect that rear element shape also is mixed into the equation.

For instance, it has been pretty well documented that the Tamron SP 90mm f/2.5 Macro (models 52B and 52BB) causes a hot spot to appear in the center of the image with many DSLRs. I have confirmed this with my own Tamron 52B and my Canon XS. But in the case of my lens and camera, this hot spot is a rather minor one, only beginning to show once I've stopped the lens down to about f/8 or so. So, as long as I shoot with the lens fairly wide open, I'm okay.

Now the reason that has been cited for this problem with the Tamron is it has a flat rear element, which is the culprit.

I also have used quite extensively a mid-1960s vintage 55mm f/3.5 Micro-Nikkor lens with my XS. This lens is not multicoated, but I have not had a bit of problem with reflections degrading the images at all.

I also own a Century Precision Optics 500mm f/5.6 telephoto lens that also dates back to the 1960s, which I've used quite a bit with my Canon XS. It isn't multicoated, either. The pair take amazingly sharp photos. No image degradation whatsoever.

In the case of the Micro-Nikkor and the CPO 500/5.6, both have recessed front elements -- the Micro because of its lens design, and the CPO because of its integral hood. The fact that the front elements are hooded probably allows for some improved contrast, but they will have no effect in lighting conditions where the sun is not directly visible.

Bottom line, I would not pay too much attention to the opinions of others. Too many folks take it upon themselves to present "expert" opinions based only on their assumptions and not real data.

Here at mflenses, you'll have the opportunity to inquire about lenses that people have used with their DSLRs, and who can provide you with real-world data. Which is why this forum is so useful.

So, if you are enjoying good results with a lens, like your 50mm Series E, then it, by definition, works well with your setup. And you have just passed along this useful bit of information to the rest of us here. Backing up your observations with photographs is always helpful and welcome as well.

F16SUNSHINE · Expire: 2011-11-18

Multi coating will always give the best results in terms of Contrast, Saturation, and Color.
But what if you want low contrast or saturation. Or colors on the muted side for that matter.
Getting to know what to expect from different lenses will help improve any photogs ability to "make" the image that you want.
Try a some and see for yourself. There is really no best if it's not what you need for the situation.
I often will use a single coated lens when shooting B+W film as it seems to improve shadow detail. These is the case even though I have lenses with the very "best" modern coatings.

BTW A hood on a lens will always improve results performance more than late stage coatings.

Henry Fisher · Joined: 11 Oct 2008 Posts: 20 Location: USA

.
Thanks, Guys, for those thoughtful responses.

As noted, there are doubtlessly some self-appointed experts who are not really close to the problem, but who may be mouthing bits and pieces of things they have read somewhere, or some such. I agree that it is a much better idea to test individual lenses, and let this forum serve as a clearing house for information about what actually works and what does not.

The MF lenses I will be checking out are as follows:

Nikkors 24f2.8, 28f3.5, 35f2.8, 35~105f3.5, 43~86f3.5, 50f1.4, 50f1.8, 105f2.5, 135f3.5, 200f4, 500f8r, and a Kiron 80~200f4.

I found the idea about the flat rear element to be an interesting one. I will be looking for a correlation between that and the sensor, if I have any such lenses.

It is refreshing to find such seasoned and expert help as is available here. Needless to say, I am honored to be in your company.

Happy day.

Smile

aoleg · Joined: 22 Feb 2008 Posts: 1387 Location: Berlin, DE

The issue of single vs. multicoating has been debated before. MC sure helps boost contrast and saturation, but it is not the only factor, and not even the most important one.

First, there's lens design. The more air/glass surfaces a lens has, the more important is multicoating. Old designs such as Sonnar were made to minimize the number of air/glass surfaces by combining elements into groups. Nikkor-Q, Nikkor-Q.C., and the 'K' version of 135/3.5 were Sonnar designs with 4 lens elements in 3 groups. As such, coatings did not affect contrast much. Similarly, Sonnar-based Nikkor-P 105/2.5 (silver-nose) is 5 lenses in 3 groups; it gives excellent contrast even in the shadow.

Second, it's blackening of lens edges and baffling/matting of internal surfaces. Unfortunately, many lenses, especially in the USSR and Russia, were built without due care in this respect. I have a fully multi-coated Jupiter-9 that has LOWER contrast than a single-coated version made 30 years before it. This is because this lens was mass-produced and assembled without properly blackening edges of lens elements; disassembling the lens completely and painting each lens edge with matte black paint improves contrast dramatically. Similar problems were noted with many other Soviet and Russian lenses, especially telephoto ones (wide-angles are surprisingly flare-resistant even in single-coated variants, e.g. Mir-10A).

Finally, it's cutting stray light from the back of the lens. Stray light can reflect inside the camera tunnel, causing loss of contrast and over/underexposure.

Orio · Expire: 2012-12-04

It's not only a matter of multi against single.
The multicoating on my Canon EF80mm 1.8 sucks, and in some positions, the lens flares abundantly, even with a lens hood on.
The single coatings on some of my old lenses are better than the multi of the Canon EF80mm 1.8

no-X · Mon Feb 08, 2010 12:18 pm

I have no proof of that, but I think, that in past the optical designs were created with respect to prevent flaring - the old designers tried to avoid specific shapes of neighbouring air-glass surfaces, which could cause strong flares. Now lenses are designed by computer programs with MTF curves as priority...

visualopsins · Expire: 2027-07-11

Orio · Expire: 2012-12-04

kds315* · Expire: 2021-03-09

Orio · Expire: 2012-12-04

visualopsins · Expire: 2027-07-11

to clarify Sigma "DG" designation:

"DG Lens
The most suitable lenses for 35mm film single-lens reflex cameras, as well as for digital SLR cameras. Sigma's development of the DG (Digital) range of lenses has concentrated on the correction of distortion and aberrations. Magnification of chromatic aberration is particularly conspicuous with digital cameras. The optical designs and cutting-edge technology incorporated by Sigma eliminate flare and ghosting from te image sensor and create excellent color balance. Vignetting is minimized whilst marginal illumination is ensured. These high performance lenses are equally suited for digital and analogue cameras."

ref: http://www.sigmaphoto.com/lenses/lenses.asp (scroll down)

dnas · Joined: 14 Nov 2008 Posts: 488 Location: Japan

kds315* · Expire: 2021-03-09

That could well be caused by a high IR sensitivity of the camera used (more precisely of a too weak internal blocking filter). I would try a a UV/IR cut filter on the lens and see if that hotspot disappears. Unfortunately good such filters are not cheap....

Attila · Expire: 2025-11-18

dnas · Joined: 14 Nov 2008 Posts: 488 Location: Japan

Esox lucius · Expire: 2011-11-18