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Old Aug 1, 2008, 9:41 PM   #1
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I received my Sigma 24-60mm f2.8 EX DG Wednesday. It pointed out the slight front focus that I thought I had on my K100D. I had read how to get into debug mode on another forum, and decided to give it a try.

I found you really have to make quite a few adjustment increments to get a minor change in the FF or BF direction, but the procedure does work.

A few samples:







Too soon to draw conclusions, but my first impression is very favorable. Lens is big, heavy and seems well built. 77mm front filter. I was expecting an aperature ring, but there is none. I wouldn't use it anyway. To manual focus you haveto put the camera in MF.There is a zoom lock switch, but at this point the zoom ring is well damped with no drift. Lens has internal focus, front element does not turn and no change in length. AF speed seems on par with my other lenses, kit, DA50-200, FA50/1.4, and quicker than Tamron 70-300.

For $200 I am favorably impressed.

Thanks Daniel forconvincingme on the Sigma 24-60.

Jim

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Old Aug 2, 2008, 12:06 AM   #2
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Seems sharp enough - nice pictures. I like the blue butterfly on the flowers, it shows how small they can be. What's it like at f2.8?
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Old Aug 2, 2008, 10:35 AM   #3
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I used mine regularly through vacation last week and I have been very impressed with this lens too. I find my copy is surprisingly good wide open and very sharp at F4. I also bought mine after Daniel's recommendation and I could not be happier with the performance/price equation. Nice flower shots a200, the close focusing is really nice, huh?

Tim
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Old Aug 2, 2008, 12:06 PM   #4
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mtngal wrote:
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Seems sharp enough - nice pictures. I like the blue butterfly on the flowers, it shows how small they can be. What's it like at f2.8?
Thanks Harriet, f2.8 is acceptable, not as sharp as f4. But overall I'm impressed with it. I wish I had it last year when I shot my son's wedding with the kit lens. Everyone was happy with the wedding shots I took, but the 24-60 would have given me a higher percentage of keepers.
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Old Aug 2, 2008, 12:07 PM   #5
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NonEntity1 wrote:
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Nice flower shots a200, the close focusing is really nice, huh?

Tim
It sure is. An unexpected benefit. Thanks for your comments.

Jim
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Old Aug 2, 2008, 5:59 PM   #6
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a200user wrote:
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mtngal wrote:
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Seems sharp enough - nice pictures.* I like the blue butterfly on the flowers, it shows how small they can be.* What's it like at f2.8?
Thanks Harriet, f2.8 is acceptable, not as sharp as f4.* But overall I'm impressed with it.* I wish I had it last year when I shot my son's wedding with the kit lens.* Everyone was happy with the wedding shots I took, but the 24-60 would have given me a higher percentage of keepers.
Jim & Tim

Nice to hear that both of you have got good copies. And we can never ignore the chance of getting a lemon knowing that other forum members do get hassle repairing/returning even more expensive lens.
The Sigma zoom is a very formidable altenative priced just higher than the kit lens and very much lower than the Tamron 28-70mm not to mention the DA*zoom.

Daniel
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Old Aug 2, 2008, 8:40 PM   #7
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danielchtong wrote:
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The Sigma zoom is a very formidable altenative priced just higher than the kit lens and very much lower than the Tamron 28-70mm not to mention the DA*zoom.

Daniel
Hi Daniel, thanks again for the advice. I'm sure the DA*16-50 f2.8 is a great lens and other than the wider view it's hard for me to justify that it's worth 3 times as much as this Sigma.

Jim
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Old Aug 6, 2008, 11:53 AM   #8
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Nice lens Jim....How did the focus adjustment go? Any problems there?

Dawg
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Old Aug 6, 2008, 10:04 PM   #9
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bigdawg wrote:
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Nice lens Jim....How did the focus adjustment go? Any problems there?

Dawg
Hi Dawg,

I have the k100D and I found this procedure on another forum which I have added my edits to so others don't get confused like I did.

1. Power OFF
While pressing [AE-L]+[INFO], turn the camera on. It helps to have 3 hands here.
Firmware is desplayed on LCD.
Press [MENU]->[MENU]->[INFO] within3 seconds. You have to be quick here.
You can seeDEBUG mode screen.
By pressing [Right key],Make [DEBUG MODE DIS] to [DEBUG MODE EN]. In otherwords changeDEBUG from disabled to enabled.
Then, Press [OK].

At this point you will see some criptique information on your LCD along with the word WAITING ...... at the top of the screen. This threw me the first few times I tried it. I sat and waited while nothing happened. Just ingore what you see on the screen and go to the next step.

2. Press [MENU], and go to thesetup menu. The menu fucntions seem to display the same as normal except for having a few more options on the last screen of the setup menu.
By pressing [Up key] which takes you to the last screen,select AF TEST.
By pressing [Right key], go into AF TEST menu.
By pressing [Down key], select FOCUS CORR. Do not touch the AF Area Test.
now you can adjust shift amount by pressing [right key] or [left key]. Left to correct for front focus, right to adjust for back focus. After changing the value, Press [OK] to save.

The camera will still be in dubug mode but will function. You will notice a lot of code on the LCD screen when the auto preview comes up after taking each shot.

3. Test your camera that Focus is corrected.I printed a focus test chart that I found by doing a google search, mounted my camera on a tripod, and got as close to a 45 degree angle above the test chart as I could. I took a shot at the widest aperature to get the least depth of field which makes it easier to determine if you are still FF or BF.

Repeat step 2 and 3 untill you are satisfied that the focus point is correct. I did this several times with each of my lenses to get the best possible setting for the lenses I have. This takes a little compromising because you can't retain a setting for each lens. My K100D seemed to have a minor FF for all my lenses, with the FA50mm f1.4 showing the least.

I have to say at this point that I moved left 10 increments to correct what I considered to be a minor FF issue. Hope this saves someone some trial and error time.

4. Now the trick is to get the camera out of DEBUG mode.You have to do that in the same wayyou got into it. Turn the camera off.
Then while pressing [AE-L]+[INFO], turn the camera on.
Firmware is desplayed on LCD.
Press [MENU]->[MENU]->[INFO] within3 seconds. Be quick.
You can seeDEBUG mode screen.
By pressing [Right key],Make [DEBUG MODE EN] to [DEBUG MODE DIS].
Then, Press [OK]. In other words you need to disable debug mode.

To get in or out of DEBUG mode you have to turn the camera off and turn it on again while pressing AE-L and INFO.

I read about this procedure quite some time ago, but waited until my warantee had expired before I actually tried it.Pentax does not recommend this for non-geeks.

So to answer your question Dawg, It was quick and easy...................... NOT :?

It sounds likePentax has made this procedure painless on the K20D whereyou can make individual adjustments forseveral lenses.

MEMO TO SELF: Save money for K20D!



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Old Aug 10, 2008, 12:33 PM   #10
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Jim

Thanks for the details. I have K100D and I have copied all the steps just in case I need that . It is possible that I have BF/FF in a couple of my lenses and I did not give it a complete checkup yet. There is on the web a focus chart that seems to be Pentax approved.

Daniel
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