[January]

I got a Pentax DSLR primarily to use my beloved old-fashined M42 lenses. After having tried a couple of alternatives (a Canon EOS DSLR, a micro 4/3 camera I still use and love), I got a K30 a couple of years ago, due to its alleged compatibility with old lenses, built-in NR, because it appeared to have great features, and, not least, because I associate the name with the Spotmatic, a camera I could never afford, but which also used the M42 like my Zenit and, later, Praktica.

The experience has been rather underwhelming. There is a lot of great stuff, and I shot a ton of photographs, but I was frankly hoping for the camera to get along better with my lenses. In particular I barely managed a good shot out of my Pancolar, which served me well for many years and which I think is the sharpest lens in my posession (maybe along the Sonnar 135). Also, I was not very lucky with the adapters, despite of paying sometimes what I felt were not trivial sums. Canon adapters are way more sturdy – no wonder, given the smaller flange distance of the EF/S mount. In any case, the Pentax to M42 adapters tend to break or get stuck precisely at the moment when I have no tools in hand and I am in a hurry.

My main issue at the moment is that weirdly, all manual lenses I have (at least all I tried in controlled settings) front focus, something that does not seem to be the case with the two low-end zooms I also have (kit 18-55 and an old Sigma 70-210). Arguably, the latter two are much darker so any problems with focus would be less apparent, but I am quite convinced after several series of experiments (don't laugh, I am a statistician by trade, so I do replicates :-)) that they focus OK.

First thing I did, roughly four or five years ago was to service the camera to make sure it is properly calibrated. This did not resolve my issues.

For a while I was relying on focusing without relying on the AF measurement. However, I think the warranty on my eyes run out a while ago ;-) what with them being older than most of my M42 lenses, and this no longer works as well as it used to. Using live view is not practicable in many circumstances, and having to use my reading glasses to do so is also annoying.

Today, I use the "fine tuning" correction which I need to remember to switch on when mounting a manual lens. I set it to the maximum negative value which still does not bring the focus perfectly to where it should be, but is more than sufficient for everyday purposes. It's not perfect, though. Also, especially for the wide angle lenses (Flektogon 20mm, Flektogon 35mm, Sigma 28mm) it seems to be more or less erratic (large dispertion), so I tend to shoot a series, each time focusing again, hoping one of them will work. All in all, the signal/noise ratio (useful/useless photographs) is pretty low. Also, I tend to forget to switch the fine tuning (brain warranty period also ended a while ago).

And yes, stepping down usually helps, but what is the point of having a 1.4 or 1.7 with a nice bokeh if you have to step it down to 5.6?

Here, a few questions.

1) is it possible to automatize that procedure somehow? To make sure that the fine tuning is applied only to manual lenses? I read somewhere that mixing lense-specific settings and "apply to all" results in unpredictable behavior. I tried to use it, setting it to 0 for the zoom lenses I have, but it still seemed that the camera applied the negative "all" value.
2) is it possible to have a one-button press for selecting the focal length of the manual lens, rather than having to switch the camera off and on again when I change the lenses?
3) is this phenomenon (front focus only for manual lenses) a thing? I mean, have you also observed something like this?
4) is there any other general advice you could give me?

Thank you,

j.

[luftfluss]

I had good success using my K-30 with manual focus, and part of the learning curve was realizing that just because the camera thought the subject was in focus, it often wasn't - I would have to turn the focus ring just a smidgen further.

I'll admit that I just skimmed your post but have you checked out this article?

Achieving Better Manual Focus with the Green Hexagon - PentaxForums.com

[Henrico]

My experiences shooting pictures with narrow DOF (wide open and tele) owith my K1ii and KP are that the tolerances sensor/mirror/AF-module/mat-glass are not precise enough. That was also the case in my film days, using my M50/1.4 wide open on my ME-super resulted always a little back-focus, while I was sure it was correct on my split-screen.

So what I do now in those cases is using Live View and electronic magnification. That works perfect.

That's the reason I hope once there will be a K-mount FF MILC with EVF. That would mean full functionality with manual lenses and extremely secure manual focussing. In those cases (narrow DOF) OVF's are not reliable enough...

[AfterPentax Mark II]

I use the "fine tuning" correction which I need to remember to switch on when mounting a manual lens

The fine tuning ONLY applies to AF lenses, it does not work with manual focusing lenses. The fine tuning for manual focusing lenses is done by your local optician, just like me.

And yes, stepping down usually helps, but what is the point of having a 1.4 or 1.7 with a nice bokeh if you have to step it down to 5.6?

Stepping down in this case is necessary to not get a picture that is only bokeh.

[pschlute]

In any case, the Pentax to M42 adapters tend to break or get stuck precisely at the moment when I have no tools in hand and I am in a hurry.

Nonsense. I bought my one and only M42 adapter around 35 years ago. I have never needed to buy another. Are you using a genuine Pentax one ?

My main issue at the moment is that weirdly, all manual lenses I have (at least all I tried in controlled settings) front focus

A manual lens by itself cannot front focus. Two things can occur however....
1. The focus screen is out of alignment. You said you had the camera serviced. Did they mention this ?
2. If you rely on the AF confirmation (green hexagon/beep), this is part of the AF system and it is possible the AF registration distance is out of alignment. Again if you had the camera serviced this should have been checked.

1) is it possible to automatize that procedure somehow? To make sure that the fine tuning is applied only to manual lenses?

Yes. Exit the AF/FA menu from the Apply One setting.

I read somewhere that mixing lense-specific settings and "apply to all" results in unpredictable behavior

No, that is incorrect.

2) is it possible to have a one-button press for selecting the focal length of the manual lens, rather than having to switch the camera off and on again when I change the lenses?

Yes, use the INFO screen. The process will be slower than switching the camera on and off, but you can use that method if you wish

4) is there any other general advice you could give me?

The AF/FA menu is not just for setting an adjustment, but for telling the camera what setting to use. .......

You may input one general setting (Apply All) which will apply to all lenses that are not set individually.
You may input a number of individual settings which are lens specific (Apply one). Lens must be one that the camera can recognise.

When you exit the AF/FA menu and do so from the Apply One setting the following behaviour will occur.:

If a lens is mounted which the camera can recognize and has had a Apply One setting set....that setting will be used
If a lens is mounted which the camera cannot recognize, the Apply All setting will be used.



When you exit the menu from the Apply All setting the following behaviour will occur:

Any lens mounted on the camera will have the Apply All setting applied to it (even if you have set up a Apply One setting for it.

[January]

Thank you all for your replies.

I'll admit that I just skimmed your post but have you checked out this article?
Achieving Better Manual Focus with the Green Hexagon - PentaxForums.com

Ah, this is really interesting; it appears I am not alone ;-) Thank you.

The fine tuning ONLY applies to AF lenses, it does not work with manual focusing lenses.

I am confused; can you elaborate? The article mentioned by luftfluss seems to disagree, given that it shows how to use fine tuning with manual lenses, and my own experience was that changing the fine tuning changes which areas are indicated as in focus by the green hexagon also when using manual lenses.

My experiences shooting pictures with narrow DOF (wide open and tele) owith my K1ii and KP are that the tolerances sensor/mirror/AF-module/mat-glass are not precise enough. That was also the case in my film days, using my M50/1.4 wide open on my ME-super resulted always a little back-focus, while I was sure it was correct on my split-screen.

Well, I used to photograph with Zenit (mat-glass) and Praktica, Ricoh and a few others (split-circle), and it was way easier to focus than either with AF-module or unaided eye in my Pentax DSLR. My Pentax is able to edit photographs, follow the stars, reduce the noise and record movies, but making a sharp picture from a tripod is harder than on my forty year old Praktica.

So what I do now in those cases is using Live View and electronic magnification. That works perfect.

It does not work as well for me. First, it works only in some circumstances; a little sun is enough to render the back panel invisible. Then, I need to find my glasses, and while I fumble for them, my object disappears behind the horizon. Finally, it is much less convenient and stable to hold the camera in outstretched hands as opposed to pressing it to ones nose. I have a mirrorless Olympus pen which I often take with me (it *is* much smaller), but I do use sometimes one of this plastic cones with a lens that can be magnetically attached to the LCD panel so I can view it even in full sun. But that is also not a perfect solution.

Yes, use the INFO screen. The process will be slower than switching the camera on and off, but you can use that method if you wish

Maybe I am doing something incorrectly, but I was not able to assign this option to the Info-menu quick selection. I can only change this by going into the setup menu -> camera -> 3 -> input focal length, but that is pretty far from a "one button". In an ideal world, the camera would recognize that a manual lens is attached immediately after me attaching the lens, and would then prompt for setting the focal length. Clearly, technically it is possible as the camera does recognize that a manual lens has been attached, but checks it only when being switched on.

A manual lens by itself cannot front focus. Two things can occur however....1. The focus screen is out of alignment.

Precisely! I would expect that either there is an identical issue for all lenses, or there is no issue at all. On the other hand, why would there be need for a customized fine tuning different for each lens used? Yet, the fine tuning setup menu clearly gives this possibility. Also, the article quoted above (and comments below it) as well as my own series of experiments all show that it is possible that different lenses show different focal behavior. But why? What is the physical reason for different behavior of the AF aid in different lenses?

Again if you had the camera serviced this should have been checked.

Yes, that is precisely what I asked them to do – given my issues with the manual lenses. However, for whatever reason, even after the servicing, the zooms appear to operate correctly, and with manual lenses I have a clear front focus. If I make a photograph of an almost horizontal ruler from about 1,5 m with my Pancolar, the real focus will consistently be almost 2cm closer to the camera then the point I was aiming at. Why does it matter? Because I love doing these cheesy portraits where the eyes are the only part of the face which is focused.

If a lens is mounted which the camera can recognize and has had a Apply One setting set....that setting will be used
If a lens is mounted which the camera cannot recognize, the Apply All setting will be used.

When you exit the menu from the Apply All setting the following behaviour will occur:

Any lens mounted on the camera will have the Apply All setting applied to it (even if you have set up a Apply One setting for it.

This is... unexpected, but it does explain a lot! Thank you.

[steephill]

One option to consider is to change the focus screen - Focusing Screen The focus screen in any DSLR is optimised for slower AF lenses and inferior to old manual focus SLR screens.

As has been said already stick to the genuine Pentax M42/K adaptor. Some third party adaptors stand proud of the lens mount and do not allow infinity focus. Remember that the purpose of this adaptor is to change the mount of your camera body and is intended to stay securely in place full time when using M42 lenses. When changing lenses you should simply unscrew the old lens and screw in the new lens. It was never intended that each lens would be fitted with its own adaptor to turn it into a K mount lens although many people do that for faster lens changes. That means compromising the safety design of the adaptor to make it easier to remove.

[UncleVanya]

You can change the focusing screen to a type that is easier to use for manual glass.

[pschlute]

One option to consider is to change the focus screen

You can change the focusing screen to a type that is easier to use for manual glass.

I believe the OP is relying exclusively on the AF confirmation to focus with manual lenses.

[35mmfilmfan]

Have you tried this ?

PENTAX Magnifier Eyecup O-ME53 reviews - Pentax Camera Accessory Review Database.

[vonBaloney]

Swapping out the focus screen for a plain S-type (Focusing Screen) and getting the shims just right is a huge help with fast manual lenses, and will improve manual metering as well. (It will make the viewer somewhat darker on slower lenses though.)

[Simon K]

I am confused; can you elaborate? The article mentioned by luftfluss seems to disagree, given that it shows how to use fine tuning with manual lenses, and my own experience was that changing the fine tuning changes which areas are indicated as in focus by the green hexagon also when using manual lenses.

The only difference between af- and manual lenses is - your hand is the focussing-motor. Issues like front or backfocus do not depend on the way the focussing mechanism is driven.

[January]

One option to consider is to change the focus screen - Focusing Screen The focus screen in any DSLR is optimised for slower AF lenses and inferior to old manual focus SLR screens.

I was considering this, but would like to first test it somewhere before risking damaging the camera in the process, and also I have seen ambiguous reviews (plus a horror story somewhere on Reddit I believe). Do you have any personal experience with that? Yeah, I was definitely thinking about that, only even after a few years I am still not sure whether I will stick to Pentax. I am posting here precisely because I need to make a decision: get rid of all the Pentax gear and switch to Canon (or something else?), or stick to Pentax for good or for worse. Right now I am at this stage of frustration that I pulled out a roll of 35mm from a freezer and dusted off my old Praktica ;-)

As has been said already stick to the genuine Pentax M42/K adaptor. Some third party adaptors stand proud of the lens mount and do not allow infinity focus.

Maybe I was unlucky or particularly careless, but the original one was the first one that got stuck and broke for me and I have thrown it away a while ago. Maybe I should give it a try. The one I can definitely recommend was made in Poland, only I for the love of Zeiss I can't find the maker anymore. It is black, and was more expensive than the Pentax one. However, I screw the adapters tight on my manual lenses, so (i) I need a whole bunch of them but (ii) I don't have to screw them in every time I switch the lens. Of course I avoid the ones sticking out ;-)

Have you tried this ?

Ooooo, this looks interesting, do you have it / does it work for you?

The only difference between af- and manual lenses is - your hand is the focussing-motor. Issues like front or backfocus do not depend on the way the focussing mechanism is driven.

That is exactly what I thought, thank you for confirming.

And thank you all for all that help!

[pschlute]

only even after a few years I am still not sure whether I will stick to Pentax. I am posting here precisely because I need to make a decision: get rid of all the Pentax gear and switch to Canon

A Canon camera will not help repair your poor eyesight. Nor will it offer you a film-SLR type focus screen.

In your situation the best advice I can give is to sell your manual focus glass and invest in a Pentax autofocus lens. This will solve your problem.

[35mmfilmfan]

<snip>

Re :O-ME53

Ooooo, this looks interesting, do you have it / does it work for you?

I have two, one on my K20D, one on my K3. For me, they help with focusing manual focus lenses, up to a 500mm f8 mirror lens, but with distance glasses on they do not show the entire frame without a little eye (or camera) movement to check the corners. Since, however, if using a long focal length lens, I am usually concentrating on the subject, I have not found this to be a problem.

HTH