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Old Sep 29, 2007, 11:37 AM   #41
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SS,
Check your PMs, I've been trying to send you the link I wasn't sure I was sending OK, you could have 3 messages.
Take note of Iras comments though it could be T mount my own is M42. ... Jack
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Old Sep 29, 2007, 11:43 AM   #42
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Hi Ira, you are absolutly right. i did not know there was a difference in the design/lens location/thread of what are termed 'mounts'. I have an old 'mount' looks almost correct for the Pentax K bayonet and it has a fine thread on the other side. But it just will not engage with my slide copier thread Almost, almost there, but will not start, probably an m42 to K mount. So I need T mount for sure. I am green on these lens location issues,

I do note experts like dawg occasionally mention loss of infinity. It would seem that if the rear of the lens is to close/far away from the film plane/chip surface it will not be able to focus down enough? i have this problem with binoculars, becauseI am 5.75- sight I cannot pull the rear optic back enough to focus unless I use my glasses! Well at leastI know now what I am hunting for thanks for the tips, Silversurfer
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Old Sep 29, 2007, 11:48 AM   #43
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SS,
Just for info ... an M42 thread is 42mm diameter at 1mm pitch
T mount is 42mm diameter at 0.75mm pitch. ... Jack
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Old Sep 29, 2007, 12:03 PM   #44
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Ops, sorry guys.... been multi-tasking for the wife on the PC and trying to get organised for next week departure. Yes finally got you message/s jachol, many thanks for your efforts. As I do not have any m42 lenses I do not want to make amistake of buying a wrong adaptor. the slide copier is a Jessop, probably a clone of an Ohnar or Panagor. It definitley has a fine thread, but the mount that came with it (an olympus om)spins on freely.

I notice there is approx. 10mm 'stagger' between the thread and the bayonet on this mount,whereas my old m42 (I think) mount has the 'noncompatible' thread 'within' the bayonet, sort of superimposed. ThisI imagine is the problem you say about lack of infinity if the lens is too far forward with this T adapter. It's nice to have informative friends ! silversurfer
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Old Sep 29, 2007, 12:13 PM   #45
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silversurfer wrote:
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Ops, sorry guys.... been multi-tasking for the wife on the PC and trying to get organised for next week departure. Yes finally got you message/s ¬*jachol, many thanks for your efforts. As I do not have any m42 lenses I do not want to make a¬*mistake of buying a wrong adaptor. the slide copier is a Jessop, probably a clone of an Ohnar or Panagor. It definitley has a fine thread, but the mount that came with it (an olympus om)¬*spins on freely.

I notice there is approx. 10mm 'stagger' between the thread and the bayonet on this mount,¬*whereas my old m42 (I think) mount has the 'noncompatible' thread 'within' the bayonet, sort of superimposed. This¬*I imagine is the problem you say about lack of infinity if the lens is too far forward with this T adapter. It's nice to have informative friends ! silversurfer
The flanged adaptors stop the M42 lens fitting flush with the K mount on the camera by a small amount, but it's enough to stop infinity focus being possible. ... Jack.
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Old Sep 29, 2007, 5:46 PM   #46
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Hi jack and Ira, note all your info. I think the best plan is to take copier with me on my searching to ensure the thread matches, I just cannot see the difference in .25mm pitch ! T mount was thought up by Tamron, perhaps they had to have there own 'patented' thread form !!!

I will watch this space for further tips, I did browse the thread on slide copying, it's a complicated subject. IfI read it right,some folk prefer to photograph the slide through their own tele/zoom macro lens, the slide suspended some distance in front of the lens. Others use a zoom copier (which was my plan) to be able to fill slide area to cover chip. But....but did not realise this 'cropping' seems to be the wrong side of the zoom range, it won't zoom OUT enough. Does this mean the copier body tube needs to actually slightly enter the camera body for the image to completley cover the chip?

As an experiment I tried my Oly C7000 compact, the lens just goes inside the tube but of course the lenses inside the copier are just not compatible with the oly on macro,I would probably needto rip out all the lenses in the copier!

I might just start reading the film scannerbook again! See what I can find in Liverpool on Monday. Regards, Silversurfer.
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Old Sep 30, 2007, 7:49 PM   #47
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Hi folks, I have just found a T mount on ebay in UK. But it is listed as for a Pentax PU ? is this the same as K ? never heard of PU, but then I have not had a lot to do with Pentax until daughter boughta K10drecently,

Oh I have picked up a Pentax 110 SLR to make a 'small' start in 'Pentaxing' (a bit of a joke with my daughter!)

thanks, Silversurfer
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Old Sep 30, 2007, 8:20 PM   #48
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silversurfer wrote:
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Hi folks, I have just found a T mount on ebay in UK. But it is listed as for a Pentax PU ? is this the same as K ? never heard of PU, but then I have not had a lot to do with Pentax until daughter boughta K10drecently,

Oh I have picked up a Pentax 110 SLR to make a 'small' start in 'Pentaxing' (a bit of a joke with my daughter!)

thanks, Silversurfer
PU stands for Pentax universal screw mount. M42 in otherwords.

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Old Oct 1, 2007, 3:50 AM   #49
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Hi dawg, you just saved me wasting my money But back to square one, trawl the camera repair shops today in town, never mind I'll find one eventually. thanks again, silversurfer
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Old Oct 1, 2007, 9:08 AM   #50
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silversurfer wrote:
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Hi dawg, you just saved me wasting my money But back to square one, trawl the camera repair shops today in town, never mind I'll find one eventually. thanks again, silversurfer
I got a T mount to K mount adapter on Ebay and have seen them on B&H Photo's web site. Also if you are looking for adapters Fotodiox is a very good place...Yes you may spend a little more there but they usually have them in stock or can special order one for you. Adorama.com is another really good place too. B&H and Adorama have such large and diverse inventories that they almost always have an item in stock. Fotodiox is very good when looking for adapters and all three ship to the UK every day.

http://www.bhphotovideo.com/bnh/cont...&Submit=Go

http://www.fotodiox.com/shop/index.p...7ced246885d9ec

http://www.adorama.com/catalog.tpl?o...%20Accessories


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