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01-11-2014, 10:34 AM   #241
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I have a question for those who've done this fix with the DA*16-50mm, as I have. It works, of course. But when I bring the raw images into Lightroom, I notice the lens data is not visible. Is there any reason why this fix might prevent lens data from coming over?

01-11-2014, 02:06 PM   #242
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I have a similar thing happen with the converted 50-135. The lens data is shown, but I have to manually select the model in ACR - used to recognise it automatically.
01-12-2014, 02:57 AM   #243
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QuoteOriginally posted by lawsonstone Quote
(...)Is there any reason why this fix might prevent lens data from coming over?
Yes, there is: it's'by fooling the camera on the lens's identity that the tweaked firmware makes the camera use screwdriven autofocus.

As a "collateral damage" RAW converters do not recognise the lens anymore either.
01-12-2014, 05:07 AM   #244
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QuoteOriginally posted by Mistral75 Quote
Yes, there is: it's'by fooling the camera on the lens's identity that the tweaked firmware makes the camera use screwdriven autofocus.

As a "collateral damage" RAW converters do not recognise the lens anymore either.
Huh? Lightroom has no problem with recognising my DA*16-50, which was converted to screw drive some time ago and has had thousands of shots put through it....

01-12-2014, 05:11 AM   #245
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SDM deactivating in DA60-250, next step

Hi, I tested for some days again the lens over athe K20 that was used for that task and on the K5 to verify if the lens mainain the new set up. I can confirm I've got a "subclassed" lens if you want and also a more frendly lens to hear. More often in fact, when composing for the shot with the SDM adjusting phases, I was very busy to check in the wievfinder for a confirmation that the lens reach the correct focus point and AF finishes their job. Hearing the more familiar AF screw buzz, it add an acoustical confirmation of AF end of works. Obviously you can continuate to check in the wievfinder too, but for not critical subject or shooting situations fom me this is another improvement!

Regarding your problems, I confirm that I don't make different tasks others that Clover indicate. The only difference is that in my case, the first time the deactivation doesn't work, re-reading the data file I find out more data and I changed also them. I try in a second time and I successful obtain no SDM driving the lens. As you can read above I actually have the lens in this mode over two camera bodies.

Thanks, regards, Duilio
01-12-2014, 11:41 AM   #246
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QuoteOriginally posted by Sandy Hancock Quote
Huh? Lightroom has no problem with recognising my 16-50, which was converted to screw drive some time ago and has had thousands of shots put through it....
Same here with DxO, I've processed many pics with it after converting my 16-50mm to screw drive.
No problems here automatically recognizing the lens
01-17-2014, 08:29 AM   #247
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hello guys, I desperately need your help: someone would have to send me the original file lenseep.lsn (also already modified fair enough) pentax 16 50? I have seen in these pages that someone posted that of the 50 135 but of course they are different. If someone could let me I would really have a huge favor




02-16-2014, 06:01 AM   #248
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Hi Guys!

I have some problems. I've got a K100D and can store&load lens eeprom from lenses without powerzoom/sdm.
But i've got problems with the Sigma 70-300 OS and the Sigma 50 F1.4 EX DG, which both use powerzoom contacts. I can store the lens eeprom but
it is every time a bit different although i didn't changed anything. And if i want to load the same eeprom to the lens it give a error.

With lenses like the 18-55 WR or Tamron 28-75 it works well. is this because the k100d hasn't got powerzoom contacts?
Or what's wrong? i read, that some deactivated their pentax sdm lens to use screw drive with their k100d, but that lenses have got the powerzoom/sdm contacts, too.

Regards from Germany,
Stefan
02-16-2014, 11:45 AM   #249
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QuoteOriginally posted by Duc-Driver Quote
But i've got problems with the Sigma 70-300 OS and the Sigma 50 F1.4 EX DG, which both use powerzoom contacts.
Why do you want to modify the data for these lenses?

The only lenses that need to be targeted are SDM lenses whose SDM motor doesn't work anymore but also have screw drive AF as a fallback option.
02-16-2014, 12:20 PM   #250
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yes, i know.
I want to modify the lensrom because of backfocus
02-16-2014, 01:59 PM   #251
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QuoteOriginally posted by lawsonstone Quote
I have a question for those who've done this fix with the DA*16-50mm, as I have. It works, of course. But when I bring the raw images into Lightroom, I notice the lens data is not visible. Is there any reason why this fix might prevent lens data from coming over?
What body are you using it with? I recall some software having problems on identifying newer Pentax lenses when used on a screwdrive-body.
If you look at exiftool's lens tag listings for the 16-50 da lens, you'll find that there's a number of entries:
'4 242' = smc PENTAX-DA* 16-50mm F2.8 ED AL [IF] SDM (SDM unused)
'7 242' = smc PENTAX-DA* 16-50mm F2.8 ED AL [IF] SDM (SDM unused)
'8 242' = smc PENTAX-DA* 16-50mm F2.8 ED AL [IF] SDM

The 4 242 was reported on pictures taken using the *ist D body while 7 424 was what was reported on a K20D. These were fixed to exiftool about a year ago (versions around 9.17 and 9.23), but I'd guess that many other programs, such as Aperture and Lightroom might not yet know about this.

Can you send me a sample image and I'll check what is being written to the lens tag.
02-16-2014, 04:09 PM   #252
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QuoteOriginally posted by Duc-Driver Quote
I want to modify the lensrom because of backfocus
How do you know which addresses in the lens data to change?

Have you compared two different copies of the same lens model?

Have you had success with fixing FF/BF this way?

The power-zoom/SDM contacts should not play any role regarding the lens data readout and writing. However, I do not have any inside knowledge.

Is it always the same addresses that change values from readout to readout?

If not, then perhaps the SDM contacts would be needed for additional power but I think that's unlikely.
02-17-2014, 01:40 AM   #253
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a guy "extract" a lensrom and has described what is responsible for what.
Here is a link, but it is in german: DSLR-Forum - Einzelnen Beitrag anzeigen - K20D - Autofokus Verst

i noticed that the lensrom is every time a bit diffrent if i store it. And if i want to load it to the lens it gives me an error...that's why i think i can't
read/load sigma lenses with powerzoom contacts on the old k100d

Last edited by Duc-Driver; 02-17-2014 at 02:48 PM.
02-19-2014, 10:47 AM   #254
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QuoteOriginally posted by FOX85 Quote
hello guys, I desperately need your help: someone would have to send me the original file lenseep.lsn (also already modified fair enough) pentax 16 50? I have seen in these pages that someone posted that of the 50 135 but of course they are different. If someone could let me I would really have a huge favor
have a look in my database,
there are a few 16-50 roms now

https://www.pentaxforums.com/forums/6-pentax-dslr-discussion/251464-collectio...ml#post2705178
02-19-2014, 01:32 PM   #255
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QuoteOriginally posted by Duc-Driver Quote
wonderful, thank you very much for the help
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