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05-04-2023, 02:57 AM   #46
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QuoteOriginally posted by Tonytee Quote
Iron. The SMC Takumar F 70 ~ 210mm is the only one I have. If you are referring to the tiny screws directly in front of the Manual Focus Ring, I would have to take it in foradjustments because these screws require a flat head screw driver and they are very tiny.
Yes, the screws are JIS standard which are rather finer than many of the precision screwdrivers we get from warehouses.

QuoteOriginally posted by Tonytee Quote
I will post an image taken earlier, of four AA batteries lined up. I focused on thesecond battery, going right to left and it seems to be excellent, focus right where it should be, taken with the SMC Pentax-FA 28 ~ 80mm. The Auto - Focus fine tuning wasset to Apply All at +10. Let me know what you think.
The 28-80mm focusing here looks OK. You may have to "Apply One" for the 70-210mm as it may be different for it.

There is a good chance that the focusing may be loose as I have found on my Pentax-F. If that is the case, the focusing can be jumpy and AFFA will be very, very tricky.

There is a quicker way to do it but I just use the older chart method. The good thing about this AFFA is that we only have to do it once for a lens - body pairing. There is a LensAlign chart that can be bought but I just made one for myself using David Liang's PDF template.


Here is a link to imaging resource's blog about the DIY.

Here is a link to the PDF template for the DIY chart.

Some users don't bother with the AFFA but if there is an issue with the focusing, usually, this is the best way to go, initially. The K-7 will store up to 20 individual lenses. I just do my AFFA on every AF lens I acquire because I don't want to worry about front-/back-focusing in the field. Cheers.

05-04-2023, 02:49 PM   #47
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QuoteOriginally posted by Iron Quote
Yes, the screws are JIS standard which are rather finer than many of the precision screwdrivers we get from warehouses.


The 28-80mm focusing here looks OK. You may have to "Apply One" for the 70-210mm as it may be different for it.

There is a good chance that the focusing may be loose as I have found on my Pentax-F. If that is the case, the focusing can be jumpy and AFFA will be very, very tricky.

There is a quicker way to do it but I just use the older chart method. The good thing about this AFFA is that we only have to do it once for a lens - body pairing. There is a LensAlign chart that can be bought but I just made one for myself using David Liang's PDF template.


Here is a link to imaging resource's blog about the DIY.

Here is a link to the PDF template for the DIY chart.

Some users don't bother with the AFFA but if there is an issue with the focusing, usually, this is the best way to go, initially. The K-7 will store up to 20 individual lenses. I just do my AFFA on every AF lens I acquire because I don't want to worry about front-/back-focusing in the field. Cheers.


Well, thank you very much for all of yours and everyone else's assistance. It is all truly appreciated. I am at a juncture now where I am convinced on what I need to do.

Sometimes in life you have to make a decision, even if it is a bad one.

Adios, Tonytee.
05-23-2023, 06:48 PM   #48
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QuoteOriginally posted by photogem Quote
Tony, the K-7 is very easy to adjust for correct AF, see here:
AF adjustment on K-7 (maybe K-5 too) - PentaxForums.com
I wish other Pentax bodies would be that easy!


If this is done correctly, you have the "apply all" which is for the camera itself.

And then one can adjust each lens "apply one".

As for the FA28-80: all three of them are very cheap on the 2-nd hand market, the power-zoom version is not recommended,
I had some pretty good samples of the non-AL version (which has a plastic K-mount, the standard version is metall!).
The AL version has one problem which it shares with those very light built late FA-Zooms (FA28-90 and particular FA28-105):
The AF "hits" pretto strong at each end because they are built so light and this can cause that the AF isn't precise. Maybe this

wasn't so much the case with the MZ 35mm bodies, I can't remember and I don't do film anymore since a long time.
Particular with the FA28-105mm/f3.2-4,5 AL IF this is too sad! This lens has the SMC ghostless coating and if one uses it manual it is

the best of those lenses (not too sharp wide open though).
Because it is so light and small (I know, the DA-L18-55 is leven lighter but doesn't deserve the name "lens" for me*)
it would be the perfect zoom for the K-S1 if 28mm is wide enough.


*Some person had tested the K70 with the DA-L18-55WR and DA-L50-200WR on a German forum:
He was very disappointed about it. Later the solenoid failed (it was a pre 1/2021 version) and he sent it to me for repair.

He forgot to take is SD card out so I could check why he was so unhappy:

First it was the not very sharp DA-L18-55!
Second: He did all his photos on AUTO Mode!

I repaired it, corrected the AF on the camera and then on the lens, it was better but still nothing special.
I sent the camera back and supplied him a small booklet I once gave to others which is called "Get out of the AUTO-Mode" (in German: Raus aus der Automatik).
Now he got himself a DA35/2,4 and is happy.

Many thanks for all of the info. It is my understanding that any Pentax lens with the DA-L are very cheap and not very reliable, at least for any respectable amount of time.

Better off to go with the DA Models for better performance and reliability. Well, I am still experiencing some serious difficulties with these issues of back and front focusing,

even after all of the adjustments. I am thinking of taking the k-7 and three Pentax auto focus lenses I have to my favorite Camera Sales & Service location and see if

they have some magic. I will post a couple of images to demonstrate.

Thanks again,

Tony

Last edited by Tonytee; 05-23-2023 at 08:32 PM.
05-24-2023, 11:41 AM   #49
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DA L and DA are not that different. Most DA L lenses have a plastic mount and donít include a hood. They also generally lack quickshift. Thatís about all the differences I am aware of.

05-24-2023, 12:58 PM   #50
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QuoteOriginally posted by UncleVanya Quote
DA L and DA are not that different. Most DA L lenses have a plastic mount and don’t include a hood. They also generally lack quickshift. That’s about all the differences I am aware of.
And possibly not much quality control.

Another quite important difference but both plastic mount:
DA-L 18-50WR = SCM
DA 18-50WR = HD coating
05-24-2023, 02:15 PM   #51
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One Anthurium Plant Subject.

I will upload two snaps of the exact same image, but at different lengths. The first image you will see where sharpness is all around the area I set my focus on and the system clearly indicated

that is where it is, however, it is not at all in focus. In fact, the first image has both problems of front and back focusing, but not on the subject. The only post I did on this image was resizing and

a touch of contrast in order to reduce some ugly haze on a day with harsh sunlight. Thanks for viewing. TT

---------- Post added 05-24-23 at 02:36 PM ----------

On this second image, one can see that the Stamen is in focus (after moving in closer to the subject) and even the front focus is better, however the back focus is sharper

than the Stamen. It makes one pause and wonder if the answer at least in this situation is to move in closer. These are images that were adjusted prior to leaving the

house and everything seemed fine. Now, one issue has come to mind and that is when I was done with each shot, I noticed the lens behaved in a bizarre manner by

moving internally and causing a delay in the image appearing on the screen. I took hold of the lens, gently moved it from side to side and could feel the optics/elements

moving, meaning it is quite possible that they have separated from the adhesive and that would explain at least in part the erratic auto focus issue.

Well, anyway here is the second image. Again, thanks for viewing. Okay, the images uploaded in reverse order, but you can tell which one is being discussed.

Tony



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Last edited by Tonytee; 05-24-2023 at 02:38 PM.
05-25-2023, 07:44 AM   #52
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QuoteOriginally posted by photogem Quote
And possibly not much quality control.

Another quite important difference but both plastic mount:
DA-L 18-50WR = SCM
DA 18-50WR = HD coating
Though true itís not the only quirk in DA vs DA L. The DA 35/2.4 has a plastic mount and lacks quickshift. Weirdly a few DA L lenses have Weather Resistance (WR).

As for QA I donít know that we can actually confirm a difference, but it makes sense that the sampling might be done less frequently.

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