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03-05-2016, 10:08 PM   #61
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Same reason I bought a drawer full of old film cameras.

03-06-2016, 03:47 AM   #62
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QuoteOriginally posted by i5_david Quote
I think you are right. So excited to see the performance of these older ASAHI lenses I have, but I always have this itchy feeling in my head, that I won't to get the manual focus managed. Are there any ressources here how to effectively learn to use manual focus? I remember how disappointed I was when I first got the 50er 1.7 and messed up literally all shots open wide on my K-x back then.



Ah Ok, we are talking about different lenses then. I assume that the K1 will work like the K1000 in regards of the viewfinder and vignetting. And on my K1000 the vignettes disappear at 18, so I thought that the K1 will have a nice 18-24mm when it


arrives


The spec states that there is a bleep when the manual lens has focused successfully with the central af point. One has to specify the focal length in the menu.
I am guessing that this will work well with the pentax legacy lenses. There is no way that pentax would develop their first FF camera without this fuction working well as they are well aware of the large inventory of legacy glass that is out there and that a significant number of cameras will be sold to those whose prime purpose is to re use their much loved lenses from the film era.
Manual focusing on the sony a7r is a joy but is an evf obviously.
03-06-2016, 04:36 AM   #63
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ah I see, the choosing of focal length has in some way then impact on the manual focus plus digital notification (red square). I thought the mere function of choosing the FL is just that it can be written on the EXIF Data file. thanks
03-06-2016, 05:07 AM   #64
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As far as I'm aware, the reason for inputting focal length is purely for the shake reduction mechanism. Focus confirmation for manual lenses uses phase detection. Manual focus confirmation will be more or less accurate depending on the individual lens.

03-06-2016, 06:18 AM   #65
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QuoteOriginally posted by i5_david Quote
ah I see, the choosing of focal length has in some way then impact on the manual focus plus digital notification (red square). I thought the mere function of choosing the FL is just that it can be written on the EXIF Data file. thanks
I think, you and others wishing to use legacy glass should bring the lenses to your local friendly camera outlet and spend a considerable time trying them out on the K1 before you part with your heard earned cash!!!!
03-06-2016, 06:21 AM   #66
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QuoteOriginally posted by ACG Quote
I think, you and others wishing to use legacy glass should bring the lenses to your local friendly camera outlet and spend a considerable time trying them out on the K1 before you part with your heard earned cash!!!!
Why is that? Manual focus lenses *will* work, with focus confirmation, on the K1. Plenty of us use old manual focus glass on our existing APS-C Pentax cameras...
03-06-2016, 06:46 AM   #67
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I can use the legacy glass on my K5 II with no problem. and I read articles that confirmed the use of legacy glass with the K-1, anyways I had a hard time to get the focus nailed on using 50 1.7 wide open. I shot a roll on my K1000 with the 50 and spilt focus screen and that photos were awesome. Was a pleasure to get them back from the lab.
I know of the "focus trap" and the "affirmation light" but I hoped there is another way to learn manual focus except shoot shoot shoot
03-06-2016, 07:06 AM   #68
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QuoteOriginally posted by i5_david Quote
I can use the legacy glass on my K5 II with no problem. and I read articles that confirmed the use of legacy glass with the K-1, anyways I had a hard time to get the focus nailed on using 50 1.7 wide open. I shot a roll on my K1000 with the 50 and spilt focus screen and that photos were awesome. Was a pleasure to get them back from the lab.
I know of the "focus trap" and the "affirmation light" but I hoped there is another way to learn manual focus except shoot shoot shoot
It took me 20 exposures to nail the exposure with my Super Tak 35 3.5 on my lens test/square off. It was the best image in the end, as judged by 75 poll respondents, but in the end I just took 10 images slightly rotating the focusing ring between exposures. The red focus confirmation I used for the first 10 exposures, none of which hit the indicated focus point. I haven't tried this with my K-5 but, you might be on to something.

---------- Post added 03-06-16 at 09:07 AM ----------

QuoteOriginally posted by monochrome Quote
Same reason I bought a drawer full of old film cameras.
Some of us just like cameras.


Last edited by normhead; 03-06-2016 at 07:22 AM.
03-06-2016, 07:18 AM   #69
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QuoteOriginally posted by normhead Quote
It took me 20 exposures to nail the exposure pm ,y Super Tak 35 3.5 on my lens test/square off. It was the best image in the end, as judged by 75 poll respondents, but in the end I just took 10 images slightly rotating the focusing ring between exposures. The red focus confirmation I used for the first 10 exposures, none of which hit the indicated focus point. I haven't tried this with my K-5 but, you might be on to something.
AF fine adjustment can help here. It should really be called "phase detect fine adjustment", as it applies to both auto and manual focusing. With a little experimentation, my commonly-used manual lenses all now focus quite reliably with focus confirmation, so long as I dial in the correct AF fine adjustment each time.
03-06-2016, 07:55 AM   #70
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AF fine adjustment, hmm never heard of that. I should experiment with that. Maybe this is what I searched for. thanks, mate!
03-06-2016, 08:47 AM   #71
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QuoteOriginally posted by i5_david Quote
AF fine adjustment, hmm never heard of that. I should experiment with that. Maybe this is what I searched for. thanks, mate!
No problem. I have a Takumar A28 f/2.8 that I used to find difficult to focus manually, but after careful AF fine adjustment I find it much easier now. 28mm is quite a wide lens to focus manually by sight alone using the standard focus screen in my K3 (well, it is for me), but since figuring out mine needs a -5 AF fine adjustment, I can focus it accurately using focus confirmation. I certainly get way more keepers now.

You do still need to bear in mind that there is a range - rather than an absolute point - where you will get focus confirmation. I find the most accurate way to nail focus (once AF fine adjustment has been sorted), is to rotate the focus ring back and forth very slightly once you get the confirmation, so you get a feel for where the centre of the range is. It's easier than it sounds and you get used to it pretty quickly.
03-06-2016, 10:12 AM   #72
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thanks for your tips and insights. When I get some time tomorrow I will give this a spin. Right now... too late, no light and no fun.
03-06-2016, 11:25 AM   #73
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I have put some thought into this and I think I understand where the fellow is coming from. I admit he is thinking about things in.. a new way.

Consider a field of view for the final image that frames a Volkswagen with proper emissions control.

1 > At 28mm on a FF, we use crop mode to frame the VW. This gives us an equivalent field of view = 42mm.

2 > At 42mm on a FF, we do not use crop mode to frame the VW. But, we see the same environmentally friendly vehicle as with 28mm+crop.

Alright, the argument is that there is more detail because longer focal length is used in scenario 2 above. Maybe...

Really, I think there is more detail when the longer focal length is used and it is for this reason: In scenario 1, the FF sensor is cropped digitally. The wider view with the 28mm lens is cropped by disregarding portions of the FF sensor and we end up with the VW front and center.. In scenario 2, all the FF sensor is used. A crop is still performed but it is done optically. The wider field of view with the 28mm lens is reduced by mounting a 42mm lens... VW front and center.

So, it could be argued the 42mm lens, being longer, provides more detail. However, I think the better argument is that the 42mm lens performs an optical crop versus the digital crop made when the 28mm lens. We all know cropping with lens is better than cropping digitally...
QuoteOriginally posted by clackers Quote
Oh, thought you were leaving!

Here we go:

"you are getting more details because of the longer focal length."

Do you remember writing that? ☺
03-06-2016, 12:42 PM   #74
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QuoteOriginally posted by ACG Quote
The spec states that there is a bleep when the manual lens has focused successfully with the central af point.
Yep

QuoteOriginally posted by ACG Quote
One has to specify the focal length in the menu.
Yep, though only for manual focus lenses lacking the data contact on the mount.

QuoteOriginally posted by i5_david Quote
ah I see, the choosing of focal length has in some way then impact on the manual focus plus digital notification (red square). I thought the mere function of choosing the FL is just that it can be written on the EXIF Data file. thanks
Neither. Usage for manual focus glass on the K-1 is unchanged from the APS-C line.

QuoteOriginally posted by BigMackCam Quote
As far as I'm aware, the reason for inputting focal length is purely for the shake reduction mechanism.
Yep, though it does have the side effect of providing the focal length value for the EXIF.

QuoteOriginally posted by BigMackCam Quote
Focus confirmation for manual lenses uses phase detection. Manual focus confirmation will be more or less accurate depending on the individual lens.
Yep, and there is the rub. Focus confirmation using PDAF is not really equivalent to good manual focus support. Performance will never be better than the underlying AF system. With PDAF on the K-1 (K-3/K-3II as well), precision with lenses faster than f/5.6 is limited when using other than the center AF points and no better than f/2.8 for the center column points.

The hierarchy of focus performance for all camera types stacks something like this (best at top):
  1. Manual focus using coincidence rangefinder -or-
    split-image rangefinder -or-
    magnified ground glass at focal plane -or-
    optimized matte field (e.g. Canon S-type with fast lens) -or-
    magnified live view (1:1*) -or-
    EVF zoomed to 1:1*
    (All of the above approximately equal in practice)
  2. CDAF
  3. F/2.8 PDAF (with fast lens) (generally limited to central region on high-end SLRs)
  4. Microprism rangefinder
  5. Stock focus screen for most dSLR cameras
  6. F/5.6 PDAF
The apparent lack of support for interchangeable screens as well as the (relatively) low viewfinder magnification impacts the scope of usability for the K-1 for the many subjects where manual focus is needed or highly preferred. Fortunately the rear LCD is a viable option for critical focus for many subjects.


Steve

* At greater than 1:1 pixel mapping (viewfinder to sensor) the view is composed of interpolated (best guess) data.

Last edited by stevebrot; 03-06-2016 at 12:58 PM.
03-06-2016, 01:07 PM   #75
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Very informative post.
Thanks Steve
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