Linear Lenses on DSLR Cameras

[colinM]

Hi All,

From what I can make out the old SLR Lenses were Linear in design ie .. light travels in a straight line to the film.

DSLR Cameras are Circular, apparently it's the properties of image capture on the Sensor.

My query being what deficiencies / abnormalities can I expect in utilizing an SLR lens on my DSLR?

Colin

[ricktas]

none at all. The issue occurs when you add something like a polariser filter. You need to get a CPL (circular polariser) rather than a linear one for a DSLR.

[Cage]

If you're using Nikon or Pentax, most of their lens from about 1970 on will mount without problem, albeit in manual mode only.

The biggest drawback with the older lens is that their coatings did not handle CA (Chromatic Aberrations), purple and green fringing in high contrast situations, as well as the newer lens with their you beaut coatings.

[colinM]

Thanks Fella's,

Was just curious, I have a few Slr lenses that have been shelved for a while, did take a few pictures and appear OK, albeit they need a bit of internal cleaning.

Colin

[jjphoto]

Hi All,

From what I can make out the old SLR Lenses were Linear in design ie .. light travels in a straight line to the film.

DSLR Cameras are Circular, apparently it's the properties of image capture on the Sensor.

My query being what deficiencies / abnormalities can I expect in utilizing an SLR lens on my DSLR?

Colin

Colin, there is essentially no difference between DSLR and SLR lenses. Look at the Canon EF lenses for example which changed very little if at all during the change from film to digital cameras (yes coatings were improved as new lenses were introduced but many of the early EF film lenses continue to be sold today).

It sounds like you are referring to the way some cameras reflect light inside them for auto focus (and possibly light metering) and these cameras need a circular polarising filter whilst pre auto focus cameras usually work with either circular or linear polarising filters.

...The biggest drawback with the older lens is that their coatings did not handle CA (Chromatic Aberrations), purple and green fringing in high contrast situations, as well as the newer lens with their you beaut coatings.

That's not quite correct.

1/ CA whether lateral or longitudinal and colour fringing has little if anything to do with the quality of the coatings, rather the design of the lens and decisions taken by the lens designers. The coatings mainly affect flare/veiling. My newest lens is the current Zeiss/Sony FE 1.8/55, and certainly not a cheap lens, has noticeable LoCA and fringing despite all the technology of 3 aspherical elements and superb coatings (which do work extremely well). By the way the FE 1.8/55 is a superb lens, I love it's wide open sharpness and it's smooth bokeh, it is just not perfect and LoCA is one of it's main faults along with onion ring bokeh due to the aspherical elements. The point is that LoCA and fringing is not unique to older lenses and is certainly not a reason to avoid using them.



The purple/green fringing above shows what happens when the focus is slightly off, either in front or behind the intended subject matter.

2/ The flat cover glass on the digital sensor reflects more light back into the lens than film did, therefore flare issues are greater with DSLR's than they were with film SLR's.

Coatings on modern lenses, ie of the digital era, are better than lenses on SLR's out of necessity but this does not mean coatings pre-digital were bad. Canons EF lenses were always superb. Many 30 year old lenses had superb coatings, eg. the Zeiss T* Contax, Rollie. Coatings are certainly better today but even lenses from the 1940's (and as early as the 1930's) had coatings and I would not consider the difference in coatings as a major issue and certainly not for lenses from the 1980's and later. Sure many lenses from the 50's, 60's and 70's had poor coatings but some were excellent too.



The lenses shown above are 20-30 years old and are in demand today for use on various digital bodies.

[arthurking83]

I'll separate my reply to these in two parts here:

If you're using Nikon or Pentax, most of their lens from about 1970 on will mount without problem, albeit in manual mode only.

be very careful with that.
BE IN DOUBT!! .. and ask.
Let us know what camera gear brands/models you have .. just in case.
eg. pre 77 era Nikon lenses, unless modified will not fit specific Nikon cameras .. but can easily fit onto others. And there's no rhyme nor reason to how this works.
eg. some of the top end camera don't allow Pre Ai lenses, yet the lowest of the low end models do!

So AKS! .. someone somewhere will know.

The biggest drawback with the older lens is that their coatings did not handle CA (Chromatic Aberrations), purple and green fringing in high contrast situations, as well as the newer lens with their you beaut coatings.[/QUOTE]

Agree 100% with JJ here. Again there is no pattern for this.
one example I'll give is the Nikon 105mm lenses that I've been exposed too.
105VR(Micro) is exceptionally bad at Ca, even tho it's the newest you beautest of Nikon's 105mm lenses .. it has nanos and EDs ..and all manner of modern goodness, but can only produce ugliness in terms of Ca!
years ago, when they were very cheap .. I had a quick play with a 105/2.5Ais at a local Cashies(idiot me should have just bought it there and then! ) .. from what I could see on the D300 back then .. zero Ca (relative) to what I'd have seen in the 105VR.
Note that this is just speculation on my part, as I didn't have the 105 mounted to compare images directly .. just that I know how bad the 105VR can be in terms of CA in similar situations.

So some(not all .. in fact very few!) old vintage lenses are fantastic in the way they can render an image .. that's why I'm so partial to them too!

Note too tho, if the lens is one of a thirdparty type .. the chances are that they don't render images all that well(compared to many of the better quality manufacturer lenses!)

so if you lens is a Vivitar, or Sigma or Tamron of an early vintage and consumer level quality .. chances are that it may not be as good as it gets.
(ps. I'm not picking on Vivitar, or Sigma or Tamron specifically here! add many other low level non branded stuff here too .. Hanimex, Soligor, etc .. just can't think of many now!)

[Nick Cliff]

I agree with Arthur re caution with older lens mounts having had a really tight fit with what I thought was a Pentax mount was actually a Nikon K mount on an old Vivitar lens!

[colinM]

Sorry Fellas,

Forgot all about this thread.

All useful information logged away.

Colin