[stevebrot]

I also remember the user "osv", the (in)famous Sony apologist, to whom Sony could do no wrong...

Several years ago I had a few exchanges with osv here and while we were equally dismissive of each other, I may offer a few words of favor their direction. On one thread, their comments regarding infinity focus and deficiencies of some lenses led to some research and testing of my own. What I found is that many things may lead to a negative conclusion. In short, they complained of poor performance at distance of certain 28mm lenses adapted to the A7 and suggested problems with attaining focus at "infinity". Included were links to several example photos, all of which went soft past about 50 meters distance when viewed at full resolution. What I discovered and/or was reminded of:

• Infinity stop calibration, even on a well-calibrated lens, is arbitrary, is usually a set multiple of the focal length (e.g. 200X), and is based on practical aspects of image resolution and limitations of focus systems. (No, not the furthest thing you might see from a high vantage point.)
• I did some actual measures with a few of my 28mm lenses in magnified live view and found most to focus to only ~60 meters distance. A few more went up against the stops at about 30 meters.
• All of the lenses in the above point performed fine at f/5.6 for general landscape photography. DOF is our friend.
• A little Google work showed me that many mirrorless users routinely use magnified view in the EVF, even for distant objects, and depend on going beyond and back to attain focus...fair enough.
• A little more Google work showed me that it is not unusual for MILC adapters to be intentionally "short" of the actual flange focal distance to allow the usage in the point above and that many are deficient in being too "long" for even the calibrated infinity focus.

Conclusion? Use care when disputing claims made by users of dissimilar kit. Also, use care when evaluating lenses when adapted to other than their native mount, particularly at infinity.*


Steve

* I saw a review a few days back claiming CA from a lens evaluated on an A6000 adapted through a Zhongyi focal reducer. I think I see the source of the CA.

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Last edited by stevebrot; 08-30-2019 at 12:40 PM.

[lakeshore]

There's some fine lenses in there that should give you good results, but M lenses in general do give you what I call a more "natural" look as opposed to the saturated and more contrasty look of the DA lenses. And if you're used to slide film, you're used to seeing more contrast and color than the lenses offer by themselves, courtesy of the film's chemicals and how they capture the light.

Nothing wrong with shooting JPEG in my opinion I do quite a bit of that, especially when I'm out with the family.

I find that newer cameras do have a better JPEG engine. My K-S1's JPEG files are quite a lot better than my K-50 files. From what I have seen, the K-70 and KP have improved even further (just to talk about the APS-C models).

Anyway, I brought up your use of slide film and the JPEG engine to give you a suggestion: whenever you are outdoors, or even indoors if the light is natural, change your setting to "Reversal Film". In fact, in my K-50 my U1 setting is already optimized for Reversal Film (in RAW+ of course, though I tend to keep a lot of the JPEGs). And the combination of the Reversal Film setting with a polarizer filter has brought me much, much pleasure recently I use this in my K-S1 as well, though I miss having User modes on that... Anyway, try it! I think you'll be pleased with the results, especially with the older glass. Just don't use it when there's artificial light, as the White Balance is fixed (just like when you're shooting real slide film ).

Thanks for the tip regarding "Reversal Film." I just took some sample shots with my K-50 and M 100mm f2.8 using that setting and compared with the "Bright" setting the colours seemed warmer. There was less blue in tree leaves and reds are definitely warmer. I didn't use a polarizer. I'll keep experimenting. Thanks again.

[onlineflyer]

I'm late to the party but why do I like old, manual lenses beside economics? Well, many are a work of art capable of creating a work of art.

Plus, I've never had a sdm failure with an old, manual lens.

[StiffLegged]

... I do have some Pentax legacy glass that I use of course on my old film cameras...and some with my DSLR cameras. Chief among the legacy lenses in my view is my 'ole favourite...a Pentax lens I bought in December '84...my SMC Pentax-A 35-105mm Macro F3.5. It's built like the proverbial tank...well finished...some say it is the stack of primes, which is high praise indeed, for a zoom lens...

I bought one this summer and have been seriously impressed by its optics. Yes, it's built like a tank; yes, it's manual focus only – but it was a bargain, is tack-sharp and plugged an irritating gap in my lens range. It's a keeper, so what's not to like?

[BigMackCam]

Several years ago I had a few exchanges with osv here and while we were equally dismissive of each other, I may offer a few words of favor their direction. On one thread, their comments regarding infinity focus and deficiencies of some lenses led to some research and testing of my own. What I found is that many things may lead to a negative conclusion. In short, they complained of poor performance at distance of certain 28mm lenses adapted to the A7 and suggested problems with attaining focus at "infinity". Included were links to several example photos, all of which went soft past about 50 meters distance when viewed at full resolution. What I discovered and/or was reminded of:

• Infinity stop calibration, even on a well-calibrated lens, is arbitrary, is usually a set multiple of the focal length (e.g. 200X), and is based on practical aspects of image resolution and limitations of focus systems. (No, not the furthest thing you might see from a high vantage point.)
• I did some actual measures with a few of my 28mm lenses in magnified live view and found most to focus to only ~60 meters distance. A few more went up against the stops at about 30 meters.
• All of the lenses in the above point performed fine at f/5.6 for general landscape photography. DOF is our friend.
• A little Google work showed me that many mirrorless users routinely use magnified view in the EVF, even for distant objects, and depend on going beyond and back to attain focus...fair enough.
• A little more Google work showed me that it is not unusual for MILC adapters to be intentionally "short" of the actual flange focal distance to allow the usage in the point above and that many are deficient in being too "long" for even the calibrated infinity focus.

Conclusion? Use care when disputing claims made by users of dissimilar kit. Also, use care when evaluating lenses when adapted to other than their native mount, particularly at infinity.*

Mirrorless adapters for legacy lenses can be a source of both wonder and exasperation. Depending on the quality, design, manufacturing tolerances and consistency in production, I've found issues with infinity focus, minimum focus distance, tilted plane of focus, off-centre positioning, internal reflections, rough or unfinished threading, diaphragm control range, light leaks, vignetting, lens-to-adaper locking and adapter-to-mount locking. Those I've highlighted are the most common, in my experience, and the problems vary not just from brand to brand or model to model, but between multiple examples of exactly the same brand and model. As expected, the cheapest no-brand adapters are typically the worst, but I have even some mid-range models that aren't perfect.

Add to this the variations in manufacturing tolerances and infinity focus calibration of some vintage lenses from a more-forgiving film era, and it's not at all uncommon to find lenses that won't focus or perform as expected on your MILC and chosen adapter combo...

[clackers]

Mirrorless adapters for legacy lenses can be a source of both wonder and exasperation. Depending on the quality, design, manufacturing tolerances and consistency in production, I've found issues with infinity focus, minimum focus distance, tilted plane of focus, off-centre positioning, internal reflections, rough or unfinished threading, diaphragm control range, light leaks, vignetting, lens-to-adaper locking and adapter-to-mount locking. Those I've highlighted are the most common, in my experience, and the problems vary not just from brand to brand or model to model, but between multiple examples of exactly the same brand and model. As expected, the cheapest no-brand adapters are typically the worst, but I have even some mid-range models that aren't perfect.

Add to this the variations in manufacturing tolerances and infinity focus calibration of some vintage lenses from a more-forgiving film era, and it's not at all uncommon to find lenses that won't focus or perform as expected on your MILC and chosen adapter combo...

Yep, Roger Cicala IIRC has spoken about the damage adapters can do to IQ, just on alignment tolerances alone.

[ZombieArmy]

Yep, Roger Cicala IIRC has spoken about the damage adapters can do to IQ, just on alignment tolerances alone.

Yeah even just the cheap M42 adapters for pentax have issues with focus and internal reflections. It's why I shelled out for the original.

Add to this the variations in manufacturing tolerances and infinity focus calibration of some vintage lenses from a more-forgiving film era, and it's not at all uncommon to find lenses that won't focus or perform as expected on your MILC and chosen adapter combo...

Not to mention that lenses over time due to use or environmental reasons actually need adjustments from a CLA. My A50 1.4 can't even focus beyond 20 feet and I know that's not supposed to happen.
Lots of these lenses can be 30-50+ years old, expecting them to not need work out of the gate is a little silly.

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Last edited by ZombieArmy; 08-30-2019 at 08:05 PM.

[niels hansen]

About 2006 there was an article in OBJEKTIV from the danish Photo Historical society about using old lenses on digital cameras. Unfortunately I cannot find the article, so this is based on memory. The difference between film and a chip was explained, the film is more tolerant in the corners. A Nikon representative told that on APS the lens should be longer than 50 mm to avoid bad corner sharpness

[Astro-Baby]

Actually, thinking about it, dont you find it remarkable that you can fit a 50 year old lens to a modern digital camera and get any results at all !!

A lens that was designed to be used with film, with the fairly wide tolerances of film and in a world where even the meanest photolab would color correct the average shooters pics. The lenses were designed with mechanical cameras with their natural vagaries of metering and shutters, to work with a film plane set at a known distance for the manufacturers equipment, the film medium was a different size etc etc.
And dont forget that your legacy glass may have been made in 1985 but many of these lenses were designed in the 1960s and sometimes as far back as the mid 50s. The maker may have upgraded the coatings, reduved the metalwork, improved the glass composition but an awful lot of the basic design will have harked back from an earlier generation of lenses.

I think its pretty amazing they work at all when mated through off brand, third party adaptors that may have sub standard glass or manufacturing work.

To be honest I wish they didnt work at all, there would be more lenses at better prices for us folk who shoot these lenses on the bodies they were designed for

[m42man]

Stevebrot said that green button metering with M series lenses can be erratic to some degree. This is good to know and validates my experience.

You could try Av mode, and use Exposure Compensation to allow for the chosen aperture. For example, if you fancy shooting at f4 with an f2 lens, add +2 stops compensation. This method should give much more consistent exposure.

Obviously not so handy if you're changing the aperture all the time, and not really so convenient if you're using a non-constant-aperture zoom, but it's definitely worth trying (and you won't have the problem of forgetting to use the green button, because you don't have to!).

[johnha]

I had problems with green button metering if the lens aperture was a bit sticky. The blades wouldn't close fully until after the camera had metered, leading to under exposure.

[stevebrot]

The difference between film and a chip was explained, the film is more tolerant in the corners. A Nikon representative told that on APS the lens should be longer than 50 mm to avoid bad corner sharpness

What does tolerance mean in this context? If a lens must be longer than 50mm to retain corner sharpness on APS-C, does that mean longer than 75mm on 24x36mm FF? (Note that Nikon continues to sell 20mm, 24mm, 28mm, and 35mm manual focus AIS Nikkor lenses that date to the 1970s marketed as appropriate for both FX and DX cameras.)


Steve

[stevebrot]

I had problems with green button metering if the lens aperture was a bit sticky. The blades wouldn't close fully until after the camera had metered, leading to under exposure.

It is likely that the blades also did not fully close for exposure either. Sticky blades are just simply bad.


Steve

[stevebrot]

You could try Av mode, and use Exposure Compensation to allow for the chosen aperture. For example, if you fancy shooting at f4 with an f2 lens, add +2 stops compensation.

Av mode with EC is handy when the aperture is fully manual (e.g. M42 lenses with A/M switch in the M position), and one knows how much compensation to dial in for that lens and the chosen aperture,* but is of limited value with K-mount lenses, most of which will meter and shoot wide open in Av mode regardless of aperture ring setting; the exception being K-mount lenses with native manual aperture. That is why I shoot my M42 and K/M lenses in M mode, using green button in live view to meter and broadly hint that others do the same.


Steve

* Positive or negative bias with stop-down metering is a strange beast and varies by camera model, lens used, and the aperture used on that particular lens. For example, f/4 on lens "A" may require +2 EV and +0.5 EV for f/5.6; lens "B" might require 0.5 EV for both f/4 and none for f/5.6.

[pres589]

With my M and K series glass, I select an aperture, exposure, and ISO that I believe is correct for the scene. I use the DoF preview to stop down the lens with the camera in M mode. The light meter display will tell me how close I am to correct with my settings. I adjust and try again with faith in post-processing to correct things a bit as needed.

Using exposure biasing for the above purpose seems very strange.