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06-10-2015, 08:37 PM   #16
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QuoteOriginally posted by pacerr Quote
I've shot a lot of older, long 200-500mm Adaptall lenses and I can make any of them compare unfavorably with my DA*300 relative to PF / CA and "fringing" in general if I work at it.
I can get them to compare unfavorably (in that regard) pretty easily. The SP Adaptalls are great and very sharp but they do purple fringe quite a bit compared to modern lenses (or even comparable OEM lenses of similar vintage) and they all seem to have that characteristic Adaptall green/magenta bokeh fringing. The exquisite 180/2.5 was mostly immune to both of those, but I still saw some purple wide-open. Most of that is correctable, thought, and many of the Adaptalls still remain good values and capable performers on modern cameras.

But the Adaptall 90/2.5 macro is actually a good example of the problem originally brought up -- this is a lens known to suffer on digital because of the reflections caused by its flat rear element (a flat rear element will reflect light off the sensor right back at the sensor, and so it bounces back and forth sometimes making a purple hotspot in the center). Which is the main reason I've avoided that lens even though it has a good reputation otherwise and I love macro lenses (and Adaptalls)...

06-10-2015, 08:57 PM   #17
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No hard-and-fast rule exists. The majority of older lenses do not have a significant problem with reflection off of the sensor, but a few have hot spots and some others have generally lower contrast. This tends to relate more to the shape of the rear element, and not so much the coatings - which have been quite good on better lenses since the late 1970s (especially so with Pentax). Very recently, the HD coatings have been another step up, but not a game-changer.

As a very general rule, the DA lenses tend to give slightly higher resolution than the FF (FA) lenses - whether film or dSLR era. The newer lens designs also tend to have better overall contrast - sometimes referred to as micro-contrast.

Also as a very general rule, the prime lenses today are not significantly different than the designs from decades ago. Over time, zooms have improved. Exceptions to the rule exist, such as the A-series 35-105 f/3.5 which is still a very good optic from 50mm upwards. Newer zooms for crop sensors that start at ultra-wide (anywhere from 8 to 16) tend to be better than older film designs because providing a wide perspective was a high priority for shooters entering the crop-sensor digital age.

As a general rule, really poor lenses from the film era are worse than the worst modern lenses. On the other hand, some film era gems remain vastly under-valued if you know the market.

Question anyone who views digital or film era lenses as always one thing or the other.
06-10-2015, 09:38 PM   #18
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The only thing that I can say as regards to 'newer' lens vs. 'older' lens would be manufacturing design/practices/tolerances.

I may be all wet here, but on some older lenses, you do end up with CA/PF more than on a similar new lens, and its possible to design/manufacture lenses easier now that handle CA/PF better (albeit with more glass/groups) than older generations did.
I do have an old Pentax M 50 f/1.4 that takes VERY nice pictures,

https://www.flickr.com/photos/formercanuck/sets/72157651379944555

I will make a general statement:
1. Many old fixed focal length lenses are as good as (or better than) modern, although some may show CA/PF
2. Many (most) modern zooms are better as far as general image quality.
06-10-2015, 09:47 PM   #19
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tvdtvdtvd is going green?

QuoteOriginally posted by tvdtvdtvd Quote
Yes, film era lenses are junk on a digital sensor. Worthless. They're doing nothing but taking up valuable
space on the shelves of photographers who could and should be shooting completely 21st century.

For convenience, film era lenses can be shipped to tvdtvdtvd for proper reclamation. No need to be bothered
by old technology.
Are you saying you're willing to recycle my worthless a* lenses for FREE? At no charge?

The Earth will thank you.

I hope you at least earn something for your laudable effort by turning the lens bodies into beautiful, vintage lens cups and selling them on your Etsy store.

06-10-2015, 10:30 PM   #20
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One of the reasons people talk about coatings with digital has to do with the fact that Nikon and especially Canon only multi coated lens elements toward the front of the lens. Pentax has always multi-coated ALL of the lens elements. Other manufacturers had problems with reflection between the rear elements and the sensor. Not so much with Pentax. Lens technology has improved in the last 40 years, however. We no longer need radioactive lens elements since there is better glass and it is easier to make aspherics. That being said, many older lenses give results that are very usable for all except pixel peepers.When an 11X14 is hanging on the wall, how many people stand six inches away with a magnifying glass.
06-10-2015, 11:49 PM   #21
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The 2 or 3 things that make modern lenses potentially different:

- coatings have improved quite a bit, and are now more effective
- digital sensor can't catch rays as the same low angle as a film could and also reflect more light
- modern lenses are designed by computer and there a tendancy to make them bigger, more corrected and so, sharper. That make them more prone to flare so the improvement in coatings is quite used here.

That being said it is only tendancies and it will depend of the exact lenses we compare and what you like. Don't assume that old lenses have to be bad performers.

I know that my F135 tend to have lot of chromatical aberations and you need to close it at least to f/5.6 to reduce them significantly or to set the software correction to its maximum value in DxO. My FA77 does it but magnitudes time less and only at the widest apperture. FA50 has the issue and is a bit in between the 2 others.

This doesn't mean the old lenses are bad. I love my FA77 rendering overall that is simply execeptionnal. It might not be technically better (even through the lense is very sharp once stopped a bit) but the overall result is more pleasing to the eyes overall, the bokeh is very creamy, it tend to produce this pixie dust/3D rendering a lot, making the subject to pop. DA70 doesn't do that as much.

On the contrary, I must admit that DA35 ltd is using the best of modern design and coating. It is extremely sharp, has incredible contrast and outstanding flare resistance and rendering is overall quite different from FA35. For landscapes, I'd choose the DA, for ultimate sharpness too as for macro. But the FA35 bokeh is better (outside of macro range) than DA35 ltd.

But really this is something that depend a lot of the exact lense you have and also the kind of results you hope for.

So for your F300 ? Well would need to compare pictures in various situations to see the difference.
06-11-2015, 03:14 AM   #22
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QuoteOriginally posted by MadMathMind Quote
Coatings have been the subject of much research over the past 40 years. You should reason that the modern coatings are better than the ones from 20 years ago. If they weren't, they wouldn't have replaced them.
Another reason is that the older coating is too expensive to produce. They may have replaced it with a cheaper coating. Cheaper does not always make it inferior...

Seb
06-11-2015, 03:25 AM   #23
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I guess I would venture to say a couple of things. First of all, there are no dogs in Pentax's line up at present, whereas there have been some pretty poor lenses sold in the past. Top glass of all generations performed and continues to perform well on digital sensors. Second, older glass is definitely more prone to fringing, which is usually fixable in post processing. Third, zooms have come a lot farther over the years than primes have. Primes from forty years ago are much more likely to be good performers on digital than zooms from the same era. Coatings have improved a lot and flare resistance on current lenses is pretty phenomenal compared to some of the older lenses (particularly non-Pentax lenses).

The final thing to me is that some of the older lenses don't have as high contrast as current lenses. This is quite different from sharpness and while it can be added in post, it can easily make photos lack pop -- at least without doing a little bit of editing after the fact.

In the end, most older lenses do well, but you do have to be a little more careful with some of them and some may have specific weak areas that need to be avoided when shooting.

06-11-2015, 03:27 AM   #24
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My take would be film lenses tend not to handle similar high contrast scene as well as digital era lenses.

Not sure whether you notice but digital era lenses handles highlights better, almost akin to having permanent highlights -5 in LR for film era lenses.

Therefore, there seems to be a more balanced exposure from the digital lenses as compared to film lenses, in a similar high contrast scene.

With regards to sharpness, seriously? I don't find myself printing larger than A4-sized regularly. Keyword: regularly.
06-11-2015, 05:01 AM   #25
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Flare check today with the K-01 locked on the tripod, while the coffee brews.
Both lenses were set at f/6.3, camera jpg, iso 100 and 1/125 sec
SMC Pentax -M Zoom 1:2.8 ~4 40~80mm ( This lens was available before 1980, I don't know how old this copy is)
https://app.box.com/s/uinq3uy9nadmbvnnfpduruseqcpylzx9

SMC Pentax -DA 1:3.5~5.6 18~55mm AL ( This lens was available from about 2004, I think this copy is about 2005)
https://app.box.com/s/84el6wl3chcaudz8a7vgdo11nm1jp6tc

I have previously put up a simiar test of this DA with the SMC Pentax -M 1:2 50mm, and that -M lens also has much better performance into sun.

Sorry I don't have any other DA lenses here to compare with those in the -M collection.
06-11-2015, 05:10 AM   #26
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QuoteOriginally posted by vagabond79 Quote
I came across a thread on dpreview where one guy claimed the following regarding an image taken with the F*300mm f/4.5 lens:

"You can see a little bit of evidence that it's a film lens, but the sharpness is definitely there.

You can see lowered contrast around picture elements. Apparently digital sensors reflect light back onto the lens more than film does, and it's corrected on DA lenses by an added coating on the rear element - and elsewhere I suppose."


The image in question can be seen here.

I've never heard this and was wondering if anybody else had any info on the subject.

Thanks.
I have found that the modern lenses are better than older film era lenses ....... for digital. But I haven't been into photography long enough to have had a good array of film era lenses and modern era lenses. So much so I'm planning to get rid of some of them. Though I do have a Sigma 50mm 1.4 which is a "digital era" lens, and is not that special. I would really need to give it another chance, but if it sucks its gone.

My DA* 16-50mm 2.8 is sharper at 50mm compared to my FA 50mm 1.4. The 16-50 is a better lens, but the FA 50mm 1.4 has taken some very nice pictures and I enjoy using it for narrow dept of field photography.

Lens designs are changing due to the artistic needs of pro photographers. Today they want lenses that are sharp wide open etc. Over the years photographers wanted better and better performance.

Digital optimized means the lens is generally sharper, to cope with the higher resolution of the mega mega pixel crop bodies. The airy discs now have to suit the finer pixel pitch.

Should all film era lenses be put on the shelf to collect dust ....... I don't think so. Some of mine are really nice, but of course I would prefer if they were modern and optimized for digital.

I think opinions on this matter will vary, so what I would do is go on search for a lens on flickr, and see what people are producing out in the field. If you like what you see, then pick up a copy.

I've seen film era lenses which seem very interesting, and I might give them a try. But they have to do something real special.

But as a rule of thumb, the modern lenses are much better.
06-11-2015, 05:57 AM   #27
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QuoteOriginally posted by pentaxus Quote
We no longer need radioactive lens elements since there is better glass and it is easier to make aspherics.
You might be overlooking the rather obvious reason for that. Everyone left Chernobyl because they found a nicer place to live and work. Yes, radioactive coating technology is something that could be done, but the costs of taking appropriate precautions would be extremely high.
06-11-2015, 06:23 AM   #28
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QuoteOriginally posted by vagabond79 Quote
You can see lowered contrast around picture elements.
I find it interesting that someone is able to attribute this to a film/digital lens difference and not a post-processing difference (including possible in-camera settings) or specific lighting conditions, or any other factors.

This kind of evaluation is easier on the internet I guess, especially with an image 560 pixels high.
06-11-2015, 06:53 AM   #29
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I don't think you can generalize too much about the film vs. digital lens debate. Yes, there are some film lenses that are stinkers ... and there are some digital lenses that are stinkers too. A lot depends on the optical design. Coating bring something to the table too but if the optical design and manufacturing control isn't present then no coating will save you.

Let's not forget Ricoh/Pentax still officially makes 4 film era lenses that "were originally designed for film SLR cameras, but they are also fully compatible with digital SLR cameras." These lenses cost some serious coin. Yes, I am talking about the FA and FA Limited series. Shall we increase that number and include the D-FA Macro lenses?

Also, many of the current DA lenses are simply updated versions of the past FA lenses. I believe the DA 35, both 40's and the 50 come from the FA series of the past. Good film lens designs! In this case, coatings are just icing on the cake compared to the actual design of the glass.
06-11-2015, 08:03 AM   #30
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A digital sensor has a flat surface where analogue film has a curved surface, this means that lenses made for film and for digital adjust the angle of light differently. This may not be a big problem in reality...
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