Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
03-29-2011, 08:06 PM   #1
Veteran Member




Join Date: Jan 2011
Location: Minahasa, North Celebes (Sulawesi)
Photos: Albums
Posts: 585
A little confusion over my Tamron Adaptall II 28mm f/2.5

Just recently bought, fine results, glad to have it. But, is this lens usually looks like this, in terms of positions?

..the scale is on the right?


..turning the focus ring to the far right, there's no lettering scale?


..turning it to the far left.. seems to be ill-positioned?


..there are two screws here. Is this normal?


..aperture stays on top


..more


..never had an adaptall before, so need somebody to enlighten me on this
-Thank You


Last edited by minahasa; 03-29-2011 at 08:43 PM.
03-29-2011, 08:12 PM   #2
Site Supporter
BigDave's Avatar

Join Date: Sep 2010
Location: Hudson Valley, NY
Photos: Gallery | Albums
Posts: 1,583
The lens aperture info should be at top (I assume you are using a k mount adapter). It looks like the adapter is not correctly attached to the lens. The tabs should fall into slots on the side of the lens. Is this a KA mount or KM mount you are using with it?

THis is a great lens and I have one myself!
03-29-2011, 08:26 PM   #3
Veteran Member




Join Date: Jan 2011
Location: Minahasa, North Celebes (Sulawesi)
Photos: Albums
Posts: 585
Original Poster
QuoteOriginally posted by BigDave Quote
The lens aperture info should be at top (I assume you are using a k mount adapter). It looks like the adapter is not correctly attached to the lens. The tabs should fall into slots on the side of the lens. Is this a KA mount or KM mount you are using with it?

THis is a great lens and I have one myself!
A great lens indeed
Yes I'm using K mount adaptall II. And the aperture tab is the top, giving correct numbering. The position of the focus scale and its numbers is confusing me. I've tried to remove the mount from the lens, put it back together again.. well, I'll try again, maybe my mistake.. however isn't the focus metering scale has nothing to do with the mount? I tried to turn the focus ring while not attached to the mount, but it still gives the wrong positioned scale
03-29-2011, 08:29 PM   #4
Site Supporter
stevebrot's Avatar

Join Date: Mar 2007
Location: Vancouver (USA)
Photos: Gallery | Albums
Posts: 26,654
Your lens has been crudely modified by someone. Neither screw belongs there.

Here is a photo of my 28/2.5 (02B) showing the scales:




Steve

03-29-2011, 08:47 PM   #5
Veteran Member




Join Date: Jan 2011
Location: Minahasa, North Celebes (Sulawesi)
Photos: Albums
Posts: 585
Original Poster
QuoteOriginally posted by stevebrot Quote
Your lens has been crudely modified by someone. Neither screw belongs there.

Here is a photo of my 28/2.5 (02B) showing the scales:




Steve
I thought so, too.
..but it still gives good images. What do you think is the problem in the first place?
03-29-2011, 09:38 PM   #6
Pentaxian




Join Date: Jan 2010
Location: Vancouver, BC
Posts: 1,421
I don't think it's been modified but someone took it apart - possibly to clean it - and put the lens back together improperly. If you look at the lens from the rear, those two screws should be at about 2 o'clock position with the aperture ring set at f2.5. On the OP's lens, the screws are at 10 o'clock position.

Minahasa, can you remove the lens from camera, remove the adaptall mount from the lens, take a picture of the rear of the lens and see if you can show where the green dot is in relation to the lens' focus hash mark. The green dots on the stainless steel female adaptall bayonet, and the one on the lens body should be lined up with the lens' focus hash mark. Somehow with your lens I don't think they line up.

Thanks,
03-29-2011, 11:07 PM   #7
Veteran Member




Join Date: Jan 2011
Location: Minahasa, North Celebes (Sulawesi)
Photos: Albums
Posts: 585
Original Poster
QuoteOriginally posted by excanonfd Quote
I don't think it's been modified but someone took it apart - possibly to clean it - and put the lens back together improperly. If you look at the lens from the rear, those two screws should be at about 2 o'clock position with the aperture ring set at f2.5. On the OP's lens, the screws are at 10 o'clock position.

Minahasa, can you remove the lens from camera, remove the adaptall mount from the lens, take a picture of the rear of the lens and see if you can show where the green dot is in relation to the lens' focus hash mark. The green dots on the stainless steel female adaptall bayonet, and the one on the lens body should be lined up with the lens' focus hash mark. Somehow with your lens I don't think they line up.

Thanks,
Okay, more pics:




So somebody take this lens apart, and misalign the lens barrels when put back together? The optics are giving good result though.. should I be worry?
03-29-2011, 11:18 PM   #8
Site Supporter
stevebrot's Avatar

Join Date: Mar 2007
Location: Vancouver (USA)
Photos: Gallery | Albums
Posts: 26,654
QuoteOriginally posted by excanonfd Quote
I don't think it's been modified but someone took it apart - possibly to clean it - and put the lens back together improperly. If you look at the lens from the rear, those two screws should be at about 2 o'clock position with the aperture ring set at f2.5. On the OP's lens, the screws are at 10 o'clock position.

Minahasa, can you remove the lens from camera, remove the adaptall mount from the lens, take a picture of the rear of the lens and see if you can show where the green dot is in relation to the lens' focus hash mark. The green dots on the stainless steel female adaptall bayonet, and the one on the lens body should be lined up with the lens' focus hash mark. Somehow with your lens I don't think they line up.

Thanks,

I stand corrected. @excanonfd is correct. The aperture ring appears to be in the correct position relative to the mount, but the piece bearing the distance scale is shifted far from where it should be. There are three set screws that appear to secure it in position.


Steve

03-30-2011, 12:32 AM   #9
Pentaxian




Join Date: Jan 2010
Location: Vancouver, BC
Posts: 1,421
QuoteOriginally posted by minahasa Quote
So somebody take this lens apart, and misalign the lens barrels when put back together? The optics are giving good result though.. should I be worry?
The lens seem to have access to all of the focal range, and the aperture control works as it should, just that you can't visually confirm them. If this don't bother you, keep it. If you are handy with jeweler's tools and have a bit of patience, you might be able to take the lens apart, and put it back together again with correct alignment.

There are four 02B from the same eBay seller with BIN price of 29.99, sadly the auction is only open to US only. They look slightly worse for wear than Steve's copy but much better shape than yours and mine.

Thanks,
03-30-2011, 01:01 AM   #10
Veteran Member




Join Date: Jan 2011
Location: Minahasa, North Celebes (Sulawesi)
Photos: Albums
Posts: 585
Original Poster
The aperture has no problem and I can visually confirm them. It's the focal scale that's out of sight. I'm seeking some kind of price reduction from the seller now, or if he ask for refund I might do it. Apart from being normal optically, I fear that this 'misalignment' could lead to other defects. The seller has also in his possession a 28/f2.8 Vivitar at the same price. I went for this lens because of the f2.5 aperture. I have M 35/f2.8 and needed a wider-faster lens, so I choose this over the Vivitar.

Do you think I should exchange this with the Vivi?
03-30-2011, 10:52 AM   #11
Veteran Member




Join Date: Jan 2011
Location: Minahasa, North Celebes (Sulawesi)
Photos: Albums
Posts: 585
Original Poster


..so I decided to give it a little 'treatment'

I found out that it's the ring where the 'window' is that misaligned. I've turned it back to the correct position but now the ring is loose and can move around freely. I notice there's three very small screws that supposed to hold this ring from moving, but neither of them is holding it now. I did not have a tiny screwdriver to try to tighten them, but will try to buy one tomorrow.



Last edited by minahasa; 03-30-2011 at 10:58 AM.
03-30-2011, 11:51 AM   #12
Pentaxian




Join Date: Jan 2010
Location: Vancouver, BC
Posts: 1,421
QuoteOriginally posted by minahasa Quote

..so I decided to give it a little 'treatment'

I found out that it's the ring where the 'window' is that misaligned. I've turned it back to the correct position but now the ring is loose and can move around freely. I notice there's three very small screws that supposed to hold this ring from moving, but neither of them is holding it now. I did not have a tiny screwdriver to try to tighten them, but will try to buy one tomorrow.

You know, you are supposed to do this after you get a partial refund - I hope you got something from the seller. Other than this misalignment, your lens seem to be in better physical condition than mine - good luck with your repair, it's fine lens and a pleasure to shoot with.

Thanks,
03-30-2011, 12:14 PM   #13
Veteran Member




Join Date: Jan 2011
Location: Minahasa, North Celebes (Sulawesi)
Photos: Albums
Posts: 585
Original Poster
The seller promised a big discount on my next shopping haha.. well, it's a worthy 'partial refund' I suppose. I found this misalignment is a minor issue that I can still live with. Other than that, this lens is quite like new, I even get the original case.
This lens has been in my possession for two days or so, and it's making me to push aside my M 35/f2.8

Thanks for your kind support

Here's a little something from this lens:
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
adaptall, k-mount, pentax lens, scale, slr lens, tamron adaptall ii
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
For Sale - Sold: Pentax FA 28mm f2.8, Pentax K 135mm f2.5, Tamron Adaptall SP 70-210 f3.5 (19AH EricR Sold Items 9 03-05-2011 04:58 PM
For Sale - Sold: Tamron 28mm f/2.5 Adaptall with Tamron Adaptall PKA mount jjdgti Sold Items 9 12-30-2010 10:00 PM
Tamron 28mm f2.5 BBAR MC adaptall 2 pdophoto Pentax SLR Lens Discussion 10 04-02-2009 03:55 PM
For Sale - Sold: Tamron Adaptall-2 28mm f/2.5 (model 02B) with P/K mount adapter RBellavance Sold Items 4 09-30-2008 03:51 PM



All times are GMT -7. The time now is 08:41 PM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top