Win a Pentax Limited Lens: Raffle Now Live!

leeak · 01-20-2015, 11:50 PM

Originally posted by LFLee

The guy now told me that after some extensive testing with another guy, he said he didn't actually got the 60-250 to work...

so as of now no one confirm this trick work on 60-250.

Thanks for following up on that. I tried myself and couldn't make it work and so I was curious if it is at all possible. Thanks again.

Kylv · 01-30-2015, 05:15 PM

Originally posted by LFLee

The guy now told me that after some extensive testing with another guy, he said he didn't actually got the 60-250 to work...

so as of now no one confirm this trick work on 60-250.

I was a little skeptical about the story you were relaying, saying that he could switch back and forth between screw drive and SDM by turning the camera on and off didn't sound right. Glad that got straightened out.

mee · 01-30-2015, 07:01 PM - **1 Like**

Originally posted by pjm1

No probs... summary instructions (detail below):

1. Use PKTether to set camera to Debug Mode
2. Use the memory card "boot file" trick to force the camera to open the full debug menu
3. Copy current lens config from EEPROM to memory card
4. Backup original config file on computer and make required edits in Notepad++
5. Copy new lens config from memory card to EEPROM & test lens works in screwdrive mode
6. Use PKTether to turn off debug mode
7. Tidy up memory card by removing "boot files"

So, here's the detail (a fair bit of copying & pasting from other sources, but worth having it all in the one place)...

1. Use PKTether to set camera to Debug Mode
a. Download the great PKTether tool and run the exe file (likely inside the zip file downloaded)
b. Turn your camera on and then connect your camera via USB to the computer
c. PKTether should show that the camera is now connected and the camera should show "PC-5" or similar message in the top LCD
d. Choose "Camera Debug Mode On" from the Debug mode menu
Done!

2. Use the memory card "boot file" trick to force the camera to open the full debug menu
a. Create a blank (empty) file on your computer called develop.mod
b. Create a second blank (empty) file on your computer in notepad. It should have one and only one line in it:
[OPEN_DEBUG_MENU]
I pressed return after typing the above, which meant there appeared to be two lines in my first - the first one above and a blank second one. That worked fine.
c. Save it and close notepad/notepad++ and rename to:
For K5 the file should be renamed to: 00077430.505 (these are all numbers, not 's' or 'o') - I have tested this and can confirm it works
For K5-ii the file should be renamed to: 00077680.536 (have not confirmed this as I don't have this camera)
For K5-iis the file should be renamed to: 00077681.541 (have not confirmed this as I don't have this camera)
Note: both of these files must be named exactly as listed and MUSTN'T have .txt (or any other) suffixes - be careful that Notepad and other apps sometimes automatically append them. Also be careful to check you are displaying the suffixes otherwise this just won't work.
d. Copy both of these files (the blank develop.mod and your second file containing the open_debug_menu command) to the root (top most) directory of your memory card
e. Put the memory card into your camera (while off) and turn the camera on. Some reports suggest leaving the card door open but I found it didn't matter
f. Your camera should now show the full 5 page (or so) debug menu
g. Do not touch any options except what's below - you could brick your camera, lens etc.

3. Copy current lens config from EEPROM to memory card
a. On the penultimate page of the full debug menu, you should find an option "LENS ROM CAMERA=>SD" or similar - basically copies the settings from the camera (or lens) to the SD card. This is what we want to do - to get a copy of the current and default configuration
b. Once completed, turn the camera off, take the card out and put it in your computer. You should see a new file called LENSEEP.LNS make a backup copy of this and keep it safe.

4. Backup original config file on computer and make required edits in Notepad++ (rather than simple Notepad as you need to see the row and column headings)
a. Having backed up the file, edit LENSEEP.LNS using Notepad++. You should see something like the following excerpt, which is one "block" of data. Depending on which DA* lens you have, you might have 4 or 8 of such blocks (starting at 0000, 0100, 0200, 0300 etc. etc):

Code:

";        -----------------------------------------------------------------------------"
";        00   01   02   03   04   05   06   07   08   09   0A   0B   0C   0D   0E   0F"
";        -----------------------------------------------------------------------------"
":0000", "28","D6","50","8A","63","84","92","6D","71","68","68","38","03","31","93","1B"
":0010", "FF","FF","FF","F1","29","63","83","90","00","76","06","51","03","0D","00","00"
":0020", "00","00","F1","C0","00","04","28","00","00","00","00","00","00","00","00","00"
":0030", "00","00","00","00","00","00","00","00","00","00","00","00","00","00","00","00"
":0040", "28","D6","50","9A","63","84","93","6D","69","68","68","34","03","31","8B","1B"
":0050", "FF","FF","FF","F1","29","63","83","91","00","76","06","51","03","0E","00","00"
":0060", "00","00","F1","C0","00","10","24","00","00","00","00","00","00","00","00","00"
":0070", "00","00","00","00","00","00","00","00","00","00","00","00","00","00","00","00"
":0080", "28","D6","50","7A","63","84","92","6D","79","68","68","38","03","31","9B","1B"
":0090", "FF","FF","FF","F1","29","63","83","90","00","76","06","51","03","0D","00","00"
":00A0", "00","00","F1","C0","00","82","2C","00","00","00","00","00","00","00","00","00"
":00B0", "00","00","00","00","00","00","00","00","00","00","00","00","00","00","00","00"
":00C0", "28","D6","50","6A","63","84","91","6D","81","68","68","38","03","31","A3","1B"
":00D0", "FF","FF","FF","F1","29","64","83","8F","00","86","06","51","03","0D","00","00"
":00E0", "00","00","F1","C0","00","86","2E","00","00","00","00","00","00","00","00","00"
":00F0", "00","00","00","00","00","00","00","00","00","00","00","00","00","00","00","00"

Note: I have highlighted the entries above, which are the four data points you need to amend in that block, and each subsequent block. For each block, it is rows xx20, xx60, xxA0 and xxE0. And for each row it will be column 03 (i.e. the forth as "00" is the first column). For each block then, you have four amendments and they're all identical - changing the C0 to 80. And that's it.

For my DA*50-135 lens there were 8 blocks with four amendments in each, so that was 32 changes, all C0 to 80. I used the Insert key to switch to overwrite mode and simply overwrote the C with an 8.

b. Confirm you've made the right changes and save the file back to the memory card (I kept a copy on my computer).
c. Take the memory card out and put back in your camera, turn it on (keep the card door open if you like) - you should be back to the full debug menu

5. Copy new lens config from memory card to EEPROM & test lens works in screwdrive mode
a. On the penultimate page again, there should be another option "LENS ROM SD=>CAMERA" - basically does the opposite of step 3a and copies your new datafile back to the EEPROM inside the camera/lens. It will say "VERIFYING" and go through the rows in the LENSEEP file until it's happy.
b. Press the menu key to exit the debug menu and check autofocus works and you can hear the screwdrive operating (easy to check with my lens as the SDM was dead - so activity meant success!)
Note: if you haven't edited the file properly, you probably won't find this step working... in my case, I had followed instructions for the DA*16-50 which only has 4 blocks rather than 8 to edit... I went back to my computer and made the other 16 edits and then it worked. So don't panic and take your time.

6. Use PKTether to turn off Debug Mode
a. Leaving your camera on, connect it via USB to the computer
b. PKTether should show that the camera is now connected and the camera should show "PC-5" or similar message in the top LCD
c. Choose "Camera Debug Mode Off" from the Debug mode menu
Done!

7. Tidy up memory card by removing "boot files"
As a final step, I deleted the "boot files" from the root directory of my memory card... I didn't want to leave them lying around just in case.

This worked great on my K5II and 16-50mm. Please note, for my K5ii, I *had* to keep the sd card door OPEN to see the full debug menu in 2e

"LENS ROM CAMERA=>SD" said "LENS ROM DAT CAMERA=>SD" on my camera -- same thing. Just make sure you get the correct ones (as there are a ton in the menu list) The options you want are on the 4th menu page, keep cycling down with the D pad on the camera.

enjoying the loud whirl of my 16-50 and the sharpness more so. hehe

John Shriver · 02-02-2015, 02:34 PM

The concept of the format of the EEPROM appears to be in US Patent 7,822,339. The patent itself is on how they added CPU to CPU communication between body and lens for SDM. But it certainly has a sensible explanation of the EEPROM data. They repeat for different focal lengths. 16 bytes per block, with two bytes each for:

Lens Type Number
Lens Serial ID
Lens Additional Capability
AF Backlash
Focal Length
Change in Focal Plane per AF Pulse
Av Value MIN
Av Value MAX

Really interesting data. The backlash would explain why a lens would only focus accurately going in one direction, not the other. Although, ultimately focus has to be determined by the AF sensor.

Now the real EEPROM data (once in camera) has 64 bytes per row, not 16 bytes per row. Patents often deliberately change things just to confuse the reader. (Such as third-party lens vendors.) Perhaps the cited prior patents (some Japanese) are more helpful.

The change of 0xC0 to 0x80 is obviously removing the "additional capability" for SDM (bit 0x40).

Nothing in there about focus shift on stop-down.

The patent also adds a new area of data at the end of the data, to allow adding the change in focus distance per pulse at different distances.

Last edited by John Shriver; 02-02-2015 at 02:40 PM.

wibbly · 02-02-2015, 02:40 PM

Very interesting john, I may be able to do something with that

Class A · 02-02-2015, 07:00 PM

Originally posted by John Shriver

The concept of the format of the EEPROM appears to be in US Patent 7,822,339.

Nice find!

Originally posted by John Shriver

Nothing in there about focus shift on stop-down.

According to the statement of a German technician the lens data does not allow to account for focus shift (at least not in a very precise way, see below). There is only one AF adjustment value per focal length (there would have to be several, depending on the aperture, if focus shift were accounted for).

However, user matthis posted the following list of correction values (I've translated the German):

Using PhotoMe and checking the manufacturer section, you'll find the following lens code (LC) fields:

LC3: K-value data. Corresponds to the gear ratio of the AF gear.
LC4: aberration correction, near distance aberration correction data.
LC5: light color aberration correction data. Correction value for light colour / longitudinal CA
LC6: open aberration data. Correction value for wide open aperture / spherical aberration.
LC7: AF minimum actuation condition. Probably a threshold value indicating when AF accuracy cannot be improved anymore.

LC8 apparently indicates the focal length.

Originally posted by John Shriver

The patent also adds a new area of data at the end of the data, to allow adding the change in focus distance per pulse at different distances.

Fig.3B of the patent provides a format.

User Voko reverse-engineered the mapping of some of the above LC fields to the lens data layout plus the position of focal length / distance dependent data from analysing/comparing multiple lens data versions for one lens.
I haven't looked at it with a lot of detail, but it seems his analysis differs from the layout provided in Fig. 3B of the patent.

The easiest way to reverse engineer the position of the AF adjustment values would be to use a Sigma dock. One would simply have to change all the AF adjustment values available in a systematic manner and then check what data positions in the lens data they affect.

It would be very easy to write software similar to the software that comes with the Sigma dock in order to calibrate all AF adjustment values of a lens, with the main difference being that for non-Sigma lenses, one would have to read and write the lens data manually with a camera body that is capable of doing so.

Michi Joel · 02-04-2015, 05:21 AM

Originally posted by aurele

Why the 55 is a sdm only lens

Next step : discover how to adjust focus correction with in lens EEPROM ?

Suddenly dead SDM lens got more value !

Good topic btw !

Really? No screwdrive hack for this lens???

Caver · 02-04-2015, 06:10 AM

Originally posted by towa

Really? No screwdrive hack for this lens???

There is no screwdrive focus at all for the DA* 55 F/1.4, this lens is just SDM - hence there is nothing to hack :P

Michi Joel · 02-04-2015, 02:09 PM

Tnx for the answer

skism · 02-05-2015, 09:14 AM

Hi everyone,

The SDM on my 16-50 DA* (well, I shouldn't say mine, I inherited it from Heie in his wonderful Fearless contest a few years back) stopped working. So....I've read about a firmware hack to get it to resort to the screwdrive. I've looked in the forum and found references to a number of cameras, but has anyone done this with a k-30? Obviously I don't want to much around without knowing what I'm doing, so any advice for this lens and the k-30 would be greatly appreciated. Thanks.

-Sean

**clackers** · 02-05-2015, 11:37 AM

Originally posted by skism

Hi everyone,

The SDM on my 16-50 DA* (well, I shouldn't say mine, I inherited it from Heie in his wonderful Fearless contest a few years back) stopped working. So....I've read about a firmware hack to get it to resort to the screwdrive. I've looked in the forum and found references to a number of cameras, but has anyone done this with a k-30? Obviously I don't want to much around without knowing what I'm doing, so any advice for this lens and the k-30 would be greatly appreciated. Thanks.

-Sean

Read through the thread, Sean. You need to do rhe procedure on an older camera. :-)

**UncleVanya** · 02-09-2015, 11:56 AM

Has anyone done this to the DA* 200 f/2.8?

trumanusa · 02-13-2015, 07:14 PM

Anyone successfully converted DA*16-50 to screw drive using K-3. Please let me know. My DA* 16-50 is showing SDM issues and i need to fix it ASAP.

**clackers** · 02-13-2015, 08:47 PM

Originally posted by trumanusa

Anyone successfully converted DA*16-50 to screw drive using K-3. Please let me know. My DA* 16-50 is showing SDM issues and i need to fix it ASAP.

Read through the thread, Truman. You need to do the procedure on an older camera, then the lens will work on your K-3. :-)

**UncleVanya** · 02-13-2015, 08:48 PM

Originally posted by trumanusa

Anyone successfully converted DA*16-50 to screw drive using K-3. Please let me know. My DA* 16-50 is showing SDM issues and i need to fix it ASAP.

I am pretty sure you need an older body. My k100d super was my plan rather than my k50.

01-30-2015, 07:01 PM - 1 Like	#438
mee Veteran Member Join Date: May 2010 Posts: 7,403	Originally posted by pjm1 No probs... summary instructions (detail below): 1. Use PKTether to set camera to Debug Mode 2. Use the memory card "boot file" trick to force the camera to open the full debug menu 3. Copy current lens config from EEPROM to memory card 4. Backup original config file on computer and make required edits in Notepad++ 5. Copy new lens config from memory card to EEPROM & test lens works in screwdrive mode 6. Use PKTether to turn off debug mode 7. Tidy up memory card by removing "boot files" So, here's the detail (a fair bit of copying & pasting from other sources, but worth having it all in the one place)... 1. Use PKTether to set camera to Debug Mode a. Download the great PKTether tool and run the exe file (likely inside the zip file downloaded) b. Turn your camera on and then connect your camera via USB to the computer c. PKTether should show that the camera is now connected and the camera should show "PC-5" or similar message in the top LCD d. Choose "Camera Debug Mode On" from the Debug mode menu Done! 2. Use the memory card "boot file" trick to force the camera to open the full debug menu a. Create a blank (empty) file on your computer called develop.mod b. Create a second blank (empty) file on your computer in notepad. It should have one and only one line in it: [OPEN_DEBUG_MENU] I pressed return after typing the above, which meant there appeared to be two lines in my first - the first one above and a blank second one. That worked fine. c. Save it and close notepad/notepad++ and rename to: For K5 the file should be renamed to: 00077430.505 (these are all numbers, not 's' or 'o') - I have tested this and can confirm it works For K5-ii the file should be renamed to: 00077680.536 (have not confirmed this as I don't have this camera) For K5-iis the file should be renamed to: 00077681.541 (have not confirmed this as I don't have this camera) Note: both of these files must be named exactly as listed and MUSTN'T have .txt (or any other) suffixes - be careful that Notepad and other apps sometimes automatically append them. Also be careful to check you are displaying the suffixes otherwise this just won't work. d. Copy both of these files (the blank develop.mod and your second file containing the open_debug_menu command) to the root (top most) directory of your memory card e. Put the memory card into your camera (while off) and turn the camera on. Some reports suggest leaving the card door open but I found it didn't matter f. Your camera should now show the full 5 page (or so) debug menu g. Do not touch any options except what's below - you could brick your camera, lens etc. 3. Copy current lens config from EEPROM to memory card a. On the penultimate page of the full debug menu, you should find an option "LENS ROM CAMERA=>SD" or similar - basically copies the settings from the camera (or lens) to the SD card. This is what we want to do - to get a copy of the current and default configuration b. Once completed, turn the camera off, take the card out and put it in your computer. You should see a new file called LENSEEP.LNS make a backup copy of this and keep it safe. 4. Backup original config file on computer and make required edits in Notepad++ (rather than simple Notepad as you need to see the row and column headings) a. Having backed up the file, edit LENSEEP.LNS using Notepad++. You should see something like the following excerpt, which is one "block" of data. Depending on which DA* lens you have, you might have 4 or 8 of such blocks (starting at 0000, 0100, 0200, 0300 etc. etc): *Code:* "; -----------------------------------------------------------------------------" "; 00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F" "; -----------------------------------------------------------------------------" ":0000", "28","D6","50","8A","63","84","92","6D","71","68","68","38","03","31","93","1B" ":0010", "FF","FF","FF","F1","29","63","83","90","00","76","06","51","03","0D","00","00" ":0020", "00","00","F1","C0","00","04","28","00","00","00","00","00","00","00","00","00" ":0030", "00","00","00","00","00","00","00","00","00","00","00","00","00","00","00","00" ":0040", "28","D6","50","9A","63","84","93","6D","69","68","68","34","03","31","8B","1B" ":0050", "FF","FF","FF","F1","29","63","83","91","00","76","06","51","03","0E","00","00" ":0060", "00","00","F1","C0","00","10","24","00","00","00","00","00","00","00","00","00" ":0070", "00","00","00","00","00","00","00","00","00","00","00","00","00","00","00","00" ":0080", "28","D6","50","7A","63","84","92","6D","79","68","68","38","03","31","9B","1B" ":0090", "FF","FF","FF","F1","29","63","83","90","00","76","06","51","03","0D","00","00" ":00A0", "00","00","F1","C0","00","82","2C","00","00","00","00","00","00","00","00","00" ":00B0", "00","00","00","00","00","00","00","00","00","00","00","00","00","00","00","00" ":00C0", "28","D6","50","6A","63","84","91","6D","81","68","68","38","03","31","A3","1B" ":00D0", "FF","FF","FF","F1","29","64","83","8F","00","86","06","51","03","0D","00","00" ":00E0", "00","00","F1","C0","00","86","2E","00","00","00","00","00","00","00","00","00" ":00F0", "00","00","00","00","00","00","00","00","00","00","00","00","00","00","00","00" Note: I have highlighted the entries above, which are the four data points you need to amend in that block, and each subsequent block. For each block, it is rows xx20, xx60, xxA0 and xxE0. And for each row it will be column 03 (i.e. the forth as "00" is the first column). For each block then, you have four amendments and they're all identical - changing the C0 to 80. And that's it. For my DA50-135 lens there were 8 blocks with four amendments in each, so that was 32 changes, all C0 to 80. I used the Insert key to switch to overwrite mode and simply overwrote the C with an 8. b. Confirm you've made the right changes and save the file back to the memory card (I kept a copy on my computer). c. Take the memory card out and put back in your camera, turn it on (keep the card door open if you like) - you should be back to the full debug menu 5. Copy new lens config from memory card to EEPROM & test lens works in screwdrive mode a. On the penultimate page again, there should be another option "LENS ROM SD=>CAMERA" - basically does the opposite of step 3a and copies your new datafile back to the EEPROM inside the camera/lens. It will say "VERIFYING" and go through the rows in the LENSEEP file until it's happy. b. Press the menu key to exit the debug menu and check autofocus works and you can hear the screwdrive operating (easy to check with my lens as the SDM was dead - so activity meant success!) Note: if you haven't edited the file properly, you probably won't find this step working... in my case, I had followed instructions for the DA16-50 which only has 4 blocks rather than 8 to edit... I went back to my computer and made the other 16 edits and then it worked. So don't panic and take your time. 6. Use PKTether to turn off Debug Mode a. Leaving your camera on, connect it via USB to the computer b. PKTether should show that the camera is now connected and the camera should show "PC-5" or similar message in the top LCD c. Choose "Camera Debug Mode Off" from the Debug mode menu Done! 7. Tidy up memory card by removing "boot files" As a final step, I deleted the "boot files" from the root directory of my memory card... I didn't want to leave them lying around just in case. This worked great on my K5II and 16-50mm. Please note, for my K5ii, I had to keep the sd card door OPEN to see the full debug menu in 2e "LENS ROM CAMERA=>SD" said "LENS ROM DAT CAMERA=>SD" on my camera -- same thing. Just make sure you get the correct ones (as there are a ton in the menu list) The options you want are on the 4th menu page, keep cycling down with the D pad on the camera. enjoying the loud whirl of my 16-50 and the sharpness more so. hehe Last edited by mee; 01-30-2015 at 07:32 PM.

02-02-2015, 02:34 PM	#439
John Shriver Senior Member Join Date: Apr 2009 Location: Arlington, MA Posts: 160	The concept of the format of the EEPROM appears to be in US Patent 7,822,339. The patent itself is on how they added CPU to CPU communication between body and lens for SDM. But it certainly has a sensible explanation of the EEPROM data. They repeat for different focal lengths. 16 bytes per block, with two bytes each for: Lens Type Number Lens Serial ID Lens Additional Capability AF Backlash Focal Length Change in Focal Plane per AF Pulse Av Value MIN Av Value MAX Really interesting data. The backlash would explain why a lens would only focus accurately going in one direction, not the other. Although, ultimately focus has to be determined by the AF sensor. Now the real EEPROM data (once in camera) has 64 bytes per row, not 16 bytes per row. Patents often deliberately change things just to confuse the reader. (Such as third-party lens vendors.) Perhaps the cited prior patents (some Japanese) are more helpful. The change of 0xC0 to 0x80 is obviously removing the "additional capability" for SDM (bit 0x40). Nothing in there about focus shift on stop-down. The patent also adds a new area of data at the end of the data, to allow adding the change in focus distance per pulse at different distances. Last edited by John Shriver; 02-02-2015 at 02:40 PM.

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01-20-2015, 11:50 PM	#436
leeak Senior Member Join Date: Sep 2007 Location: Seattle Posts: 245	Originally posted by LFLee The guy now told me that after some extensive testing with another guy, he said he didn't actually got the 60-250 to work... so as of now no one confirm this trick work on 60-250. Thanks for following up on that. I tried myself and couldn't make it work and so I was curious if it is at all possible. Thanks again.

01-30-2015, 05:15 PM	#437
Kylv Junior Member Join Date: Nov 2012 Photos: Albums Posts: 45	Originally posted by LFLee The guy now told me that after some extensive testing with another guy, he said he didn't actually got the 60-250 to work... so as of now no one confirm this trick work on 60-250. I was a little skeptical about the story you were relaying, saying that he could switch back and forth between screw drive and SDM by turning the camera on and off didn't sound right. Glad that got straightened out.

02-02-2015, 02:40 PM	#440
wibbly Veteran Member Join Date: Nov 2014 Location: Edmonton Posts: 600	Very interesting john, I may be able to do something with that

02-02-2015, 07:00 PM	#441
Class A Pentaxian Join Date: Aug 2008 Location: Wellington, New Zealand Posts: 11,251	Originally posted by John Shriver The concept of the format of the EEPROM appears to be in US Patent 7,822,339. Nice find! Originally posted by John Shriver Nothing in there about focus shift on stop-down. According to the statement of a German technician the lens data does not allow to account for focus shift (at least not in a very precise way, see below). There is only one AF adjustment value per focal length (there would have to be several, depending on the aperture, if focus shift were accounted for). However, user matthis posted the following list of correction values (I've translated the German): Using PhotoMe and checking the manufacturer section, you'll find the following lens code (LC) fields: LC3: K-value data. Corresponds to the gear ratio of the AF gear. LC4: aberration correction, near distance aberration correction data. LC5: light color aberration correction data. Correction value for light colour / longitudinal CA LC6: open aberration data. Correction value for wide open aperture / spherical aberration. LC7: AF minimum actuation condition. Probably a threshold value indicating when AF accuracy cannot be improved anymore. LC8 apparently indicates the focal length. Originally posted by John Shriver The patent also adds a new area of data at the end of the data, to allow adding the change in focus distance per pulse at different distances. Fig.3B of the patent provides a format. User Voko reverse-engineered the mapping of some of the above LC fields to the lens data layout plus the position of focal length / distance dependent data from analysing/comparing multiple lens data versions for one lens. I haven't looked at it with a lot of detail, but it seems his analysis differs from the layout provided in Fig. 3B of the patent. The easiest way to reverse engineer the position of the AF adjustment values would be to use a Sigma dock. One would simply have to change all the AF adjustment values available in a systematic manner and then check what data positions in the lens data they affect. It would be very easy to write software similar to the software that comes with the Sigma dock in order to calibrate all AF adjustment values of a lens, with the main difference being that for non-Sigma lenses, one would have to read and write the lens data manually with a camera body that is capable of doing so.

02-04-2015, 05:21 AM	#442
Michi Joel Veteran Member Join Date: Mar 2012 Location: Catalonia Photos: Albums Posts: 441	Originally posted by aurele Why the 55 is a sdm only lens Next step : discover how to adjust focus correction with in lens EEPROM ? Suddenly dead SDM lens got more value ! Good topic btw ! Really? No screwdrive hack for this lens???

02-04-2015, 06:10 AM	#443
Caver Pentaxian Join Date: Jun 2009 Location: Hungary (ex-pat from Transylvania, Romania) Photos: Gallery Posts: 541	Originally posted by towa Really? No screwdrive hack for this lens??? There is no screwdrive focus at all for the DA* 55 F/1.4, this lens is just SDM - hence there is nothing to hack :P

02-04-2015, 02:09 PM	#444
Michi Joel Veteran Member Join Date: Mar 2012 Location: Catalonia Photos: Albums Posts: 441	Tnx for the answer

02-05-2015, 09:14 AM	#445
skism Senior Member Join Date: Oct 2010 Location: Nova Scotia Photos: Gallery \| Albums Posts: 134	Hi everyone, The SDM on my 16-50 DA* (well, I shouldn't say mine, I inherited it from Heie in his wonderful Fearless contest a few years back) stopped working. So....I've read about a firmware hack to get it to resort to the screwdrive. I've looked in the forum and found references to a number of cameras, but has anyone done this with a k-30? Obviously I don't want to much around without knowing what I'm doing, so any advice for this lens and the k-30 would be greatly appreciated. Thanks. -Sean

02-05-2015, 11:37 AM	#446
clackers Otis Memorial Pentaxian Join Date: Jul 2013 Location: Melbourne Photos: Albums Posts: 16,397	Originally posted by skism Hi everyone, The SDM on my 16-50 DA* (well, I shouldn't say mine, I inherited it from Heie in his wonderful Fearless contest a few years back) stopped working. So....I've read about a firmware hack to get it to resort to the screwdrive. I've looked in the forum and found references to a number of cameras, but has anyone done this with a k-30? Obviously I don't want to much around without knowing what I'm doing, so any advice for this lens and the k-30 would be greatly appreciated. Thanks. -Sean Read through the thread, Sean. You need to do rhe procedure on an older camera. :-)

02-09-2015, 11:56 AM	#447
UncleVanya Loyal Site Supporter Join Date: Jul 2014 Photos: Gallery \| Albums Posts: 28,468	Has anyone done this to the DA* 200 f/2.8?

02-13-2015, 07:14 PM	#448
trumanusa Forum Member Join Date: Jun 2013 Posts: 87	Anyone successfully converted DA16-50 to screw drive using K-3. Please let me know. My DA 16-50 is showing SDM issues and i need to fix it ASAP.

02-13-2015, 08:47 PM	#449
clackers Otis Memorial Pentaxian Join Date: Jul 2013 Location: Melbourne Photos: Albums Posts: 16,397	Originally posted by trumanusa Anyone successfully converted DA16-50 to screw drive using K-3. Please let me know. My DA 16-50 is showing SDM issues and i need to fix it ASAP. Read through the thread, Truman. You need to do the procedure on an older camera, then the lens will work on your K-3. :-)

02-13-2015, 08:48 PM	#450
UncleVanya Loyal Site Supporter Join Date: Jul 2014 Photos: Gallery \| Albums Posts: 28,468	Originally posted by trumanusa Anyone successfully converted DA16-50 to screw drive using K-3. Please let me know. My DA 16-50 is showing SDM issues and i need to fix it ASAP. I am pretty sure you need an older body. My k100d super was my plan rather than my k50.

How to deactivate SDM and allow for screw drive autofocus with DA* 16-50mm f/2.8

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