Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
06-10-2015, 05:24 PM   #1
Senior Member




Join Date: Nov 2009
Location: Greensboro, NC
Photos: Gallery
Posts: 147
Do older "film" lenses underperform on digital cameras compared with new lenses?

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.

06-10-2015, 05:40 PM - 1 Like   #2
Pentaxian
normhead's Avatar

Join Date: Jun 2007
Location: Near Algonquin Park
Photos: Gallery | Albums
Posts: 33,132
People who say this kind of thing never post example images. And I never believe anything anyone says without sample images. This kind of thing should be so easy to demonstrate I wouldn't trust anyone who could say something like that without posting relevant examples. The thing is, if he doesn't have relevant examples, how does he even know?

It goes to his credibility your honour.

There is way to much of this stuff posted on the internet. And honestly, unless someone posted relevant images on say an F*300 and a DA*300, I wouldn't believe he knew anything relevant to either of those lenses. It may be a problem some lenses have, I doubt all lenses have the problem, and with a general statement like that it's impsoible to know what lenses are affected and which aren't. OK, maybe the guy tested every old lens and every new lens and came to this conclusion, and has not one of his sample comparison pictures left to show us.

I don't believe that.

It's just some guy mouthing off.
06-10-2015, 05:43 PM   #3
Pentaxian




Join Date: Oct 2011
Location: Savannah, GA
Posts: 5,290
Well, modern lenses do have better coatings (of course "film" lenses were getting incrementally better coatings for decades, so it is just continuing), but it is true that internal reflections can be problematic with digital (the sensor is shiny and reflects light) and SOME older lenses don't respond well to that and you can get lowered contrast or a hotspot in the middle of the image at smaller apertures (basically a ghost of the aperture opening). In the case of slightly lowered contrast, well this is digital, you just boost it. But there are a few lenses where there is a real problem (flat rear element or shiny aperture blades or other parts that are too reflective) and you can usually find comments about such things if you read enough reviews of the lens in question. It is not a monumental obstacle to using old "film" lenses though -- most are just fine and are still capable of great images. (Some lenses are even sharper than they used to be after digital correction for CA.)
06-10-2015, 05:46 PM - 9 Likes   #4
Pentaxian
tvdtvdtvd's Avatar

Join Date: Jan 2010
Posts: 1,198
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.

06-10-2015, 05:53 PM   #5
Site Supporter
Site Supporter
MadMathMind's Avatar

Join Date: Dec 2013
Location: Houston, TX
Photos: Gallery
Posts: 1,717
Biggest indicators of film lenses:
1) Purple and green fringing. Really common for fast lenses wide open. My FA31 fringes like *mad* at large apertures in high contrast areas.
2) Lower contrast in camera JPEGs. Easily fixed in Lightroom. I apply a medium or strong contrast profile to pretty much all my lenses anyway.

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.
06-10-2015, 05:55 PM   #6
Otis Memorial Pentaxian
Loyal Site Supporter
stevebrot's Avatar

Join Date: Mar 2007
Location: Vancouver (USA)
Photos: Gallery | Albums
Posts: 33,221
The issue of sensor reflections has been going around for some time and is a marketing point for "digital-optimized" lenses, most of which are optimized by the addition of better coatings. I shoot with a mix of "film" and "digital" lenses and with very few exceptions have not been able to make any generalization regarding contrast. The few exceptions are notable in that the potential for reflection is pretty evident by examination and probably was present with film as with digital.

There are a few threads on this site and elsewhere that are about specular ghosting in night shots and/or aperture shadowing, both in the absence of heavy flare. The culprit is usually a design that features a broad, flat, and projecting rear element. Light exiting the lens does so at a high angle (that is good), but has high potential to bounce to the lens and back resulting in a hot spot at or near the center of the frame or, for night shots, multiple hot spots associated with bright points.

My Auto Rikenon 55/1.4 does this quite readily and I seldom use it for digital as a result.

FWIW, I have done direct comparison of the DA 50/1.8 against the K 55/1.8 and both A and M 50/1.7 and found all four to have reliably excellent contrast, despite the former's digital "optimization".


Steve
06-10-2015, 05:57 PM - 1 Like   #7
Otis Memorial Pentaxian
Loyal Site Supporter
stevebrot's Avatar

Join Date: Mar 2007
Location: Vancouver (USA)
Photos: Gallery | Albums
Posts: 33,221
QuoteOriginally posted by MadMathMind Quote
Biggest indicators of film lenses:
1) Purple and green fringing.


Steve
06-10-2015, 05:58 PM   #8
Site Supporter
Site Supporter
jatrax's Avatar

Join Date: May 2010
Location: Washington Cascades
Photos: Gallery | Albums
Posts: 11,831
QuoteOriginally posted by vagabond79 Quote
You can see lowered contrast around picture elements.
Not sure what this means, sounds like internet BS. I looked at the image but I don't see what he is talking about. Maybe that is just my poor understanding of things photographic. His statement that sensors reflect back more light than film is often seen posted on the internet as fact. As well as that light hitting film at an angle is fine but light hitting a sensor at an angle causes problems. I have no idea if either is correct, it sounds logical. But like so many things sounding logical it is often just good basis for a myth.

I would object to any general statement that says all film lenses under perform on digital. Owners of the FA 31, 43 and 77 might object to that as well. I've seen a number of posts by owners of the F*300 claiming it performs better than the DA*300.

I can say from personal experience that SOME film lenses exhibit less contrasty results than SOME digital lenses. But never having tried those lenses on film, I cannot say that the less contrasty result is because of using it on digital or if the results would have been the same on film. Some digital lenses perform differently than other digital lenses, why should film lenses be any different?

06-10-2015, 06:00 PM   #9
Pentaxian




Join Date: Oct 2011
Location: Savannah, GA
Posts: 5,290
QuoteOriginally posted by MadMathMind Quote
1) Purple and green fringing. Really common for fast lenses wide open. My FA31 fringes like *mad* at large apertures in high contrast areas.
Some purple fringing is a digital only phenomenon, but most fringing (especially green/magenta bokeh fringing and red/yellow lateral CA) would also happen on film, so the lenses are not in a sense performing worse than they did on film (but it is easier to see the flaws on digital). As I mentioned above, lateral CA is so easily fixed now that some lenses have lost their red/yellow fringing on digital (after correction) and gained accompanying higher resolution (at least on the edges where you normally see that).
06-10-2015, 06:17 PM   #10
Otis Memorial Pentaxian
Loyal Site Supporter
stevebrot's Avatar

Join Date: Mar 2007
Location: Vancouver (USA)
Photos: Gallery | Albums
Posts: 33,221
QuoteOriginally posted by jatrax Quote
As well as that light hitting film at an angle is fine but light hitting a sensor at an angle causes problems.
...unless you are reading on a large format film forum, in which case you will find that they still believe that cos θ ^ 4 still applies to film despite the presence of digital sensors in the universe.


Steve
06-10-2015, 07:13 PM   #11
Senior Member




Join Date: Nov 2009
Location: Greensboro, NC
Photos: Gallery
Posts: 147
Original Poster
Thanks to everyone for weighing in. I had no idea this was a topic of such contention. I agree it sounds like this dude just threw this out as fact even though he has no evidence comparing the F*300 to the DA300 or any other lens. I would be interested to see the results of a film era lens tested against a similar digital lens.
06-10-2015, 07:31 PM   #12
Veteran Member
Driline's Avatar

Join Date: Dec 2012
Location: IOWA Where the Tall Corn Grows
Photos: Gallery
Posts: 2,986
It's gonna be tough finding some one with two one thousand dollar 300 mm lenses. I've got the F*300 but not the DA* 300 and have no intention on buying the latter.
06-10-2015, 07:45 PM - 1 Like   #13
Moderator
Site Supporter
Loyal Site Supporter
Sandy Hancock's Avatar

Join Date: Feb 2012
Location: Adelaide Hills, South Australia
Photos: Gallery | Albums
Posts: 7,892
I am in the process of spending a whole month shooting daily with the A50/1.2 and DA*55. So far, I'd say the modern lens has a slight edge over the vintage lens as far as micro-contrast and ultimate resolving power go, and quite a substantial edge with respect to chromatic aberration. Of course it is also weather resistant and autofocus.

If you want photos, look HERE

Later, I intend to repeat the process with the K135/2.5 vs the long end of the DA*50-135.
06-10-2015, 08:08 PM - 2 Likes   #14
Loyal Site Supporter
Loyal Site Supporter
pacerr's Avatar

Join Date: Jan 2008
Location: Paris, TN
Photos: Gallery | Albums
Posts: 2,984
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.

But for most PRACTICAL shots in the field my technique is by far the greatest difference in the various lenses. Really good shots stand on their own and rarely have the coincidence of comparison with another similar lens to contest the issue.

Modern lenses DO have their advantages, however. Not always due to IQ. AF (well used)?

Get what you can afford to shoot and become competent with it. when the day and the purse coincide LBA will strike anyway.

Last edited by pacerr; 06-10-2015 at 08:14 PM.
06-10-2015, 08:08 PM   #15
Veteran Member
GeneV's Avatar

Join Date: Oct 2008
Location: Albuquerque NM
Photos: Albums
Posts: 9,829
QuoteOriginally posted by Sandy Hancock Quote
I am in the process of spending a whole month shooting daily with the A50/1.2 and DA*55. So far, I'd say the modern lens has a slight edge over the vintage lens as far as micro-contrast and ultimate resolving power go, and quite a substantial edge with respect to chromatic aberration. Of course it is also weather resistant and autofocus.

If you want photos, look HERE

Later, I intend to repeat the process with the K135/2.5 vs the long end of the DA*50-135.
I'd be very interested in your thoughts on the 135 comparison. I own, know and love both those options, if you mean the SMC K 135/2.5. I have not done a controlled comparison, but I find each of them has qualities I really like..
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
chaos, film, flash, focus, image, k-mount, lens, lenses, pentax lens, photo, photos, primes, ratio, rule, rules, slr lens, subject, thirds
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Exposure accuracy of "A" lenses on older film bodies ("K" series) Lititz Pentax SLR Lens Discussion 20 05-26-2015 01:59 AM
Need to find info on "older " Windows browsers ... where do I post? jpzk Troubleshooting and Beginner Help 10 05-13-2015 06:30 PM
Dear, "i...i" and "r....t" on ebay, bidding on the 50-135mm lenses mee Pentax SLR Lens Discussion 64 02-07-2015 07:25 PM
Optical differences between Pentax "K", "M", and "A" lenses 6BQ5 Pentax SLR Lens Discussion 31 01-10-2014 01:02 PM
What does "auto" mean on older manual focus lenses? jonhock Pentax SLR Lens Discussion 18 12-03-2009 11:32 AM



All times are GMT -7. The time now is 07:57 PM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top