[Jewelltrail]

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I hope this post is good here. I got frustrated with my K300 f4 because it lacks a trip-pod mount and because it has horrible close focus capabilities.

So, I took my SMC, Medium Format 6 x 7 165mm f 2.8, coupled it to my MC7 Tamron 2x converter with 67 to K mount adapter and now have a Pentax 330 5.6 with exceptional close focus ability, as well as a tri-pod mount. I am very pleasantly surprised by the IQ. I think a lot of you will be also, particularly when you think 2x tele. The IQ, IMO, is a lot better than the IQ of my K300 f 4--I just sold the K300. Here are 2 shots--no cropping--no PPing--just Raws downsized:

[kacansas03]

This gets a wow from me. I have been wondering is 6 x 7 would work on a digital body and I believe I have seen the answer. But I have some questions.
I hope this post is good here. I got frustrated with my K300 f4 because it lacks a trip-pod mount and because it has horrible close focus capabilities.

Quote:
So, I took my SMC, Medium Format 6 x 7 165mm f 2.8, coupled it to my MC7 Tamron 2x converter with 67 to K mount adapter and now have a Pentax 330 5.6 with exceptional close focus ability, as well as a tri-pod mount. I am very pleasantly surprised by the IQ. I think a lot of you will be also, particularly when you think 2x tele. The IQ, IMO, is a lot better than the IQ of my K300 f 4--I just sold the K300.
End Quote.

From what you wrote I take it the 6 x 7 165 has a tripod shoe. The Tamron 2X is for 6x7. I am very surprised by the IQ With a 2X teleconverter! I can't think of any thing I own in full frame or other that will give that good of an image with a 2X! I have seen an article that stated that because the sensor size is so much smaller from 6x7 that a 6x7 lens is equal to about 25% of it's focal length on a digital. The reasoning made no sense to me since focal length is focal length and the rest is cropping just like if you took a print and laid crop boards on it. So if we think of this from FOV are we looking out a 330 mm or longer or shorter? Anybody have any idea on this? Thanks.

[dadipentak]

This gets a wow from me.

I'll join that chorus: WOW!

[Jewelltrail]

kacansas03 This gets a wow from me. I have been wondering is 6 x 7 would work on a digital body and I believe I have seen the answer. But I have some questions.

Thanks--the 67 lens on a crop sensor only uses the sweetest of the sweet spot, so the Tele does not have much in the way of imperfection to magnify by a factor of 2. The result are images even to the corners with amazing IQ--I am overwhelmed. And the lens, a 330mm 5.6, will close focus down to 5.25 feet.

kacansas: From what you wrote I take it the 6 x 7 165 has a tripod shoe. The Tamron 2X is for 6x7. I am very surprised by the IQ With a 2X teleconverter! I can't think of any thing I own in full frame or other that will give that good of an image with a 2X! I have seen an article that stated that because the sensor size is so much smaller from 6x7 that a 6x7 lens is equal to about 25% of it's focal length on a digital. The reasoning made no sense to me since focal length is focal length and the rest is cropping just like if you took a print and laid crop boards on it. So if we think of this from FOV are we looking out a 330 mm or longer or shorter? Anybody have any idea on this? Thanks.

The tri-pod mount is built into the 67 to K-mount adapter. The Tamron 2x Tele is made for Full frame K-mount lenses. I am surprised by IQ too. Yes, focal length is focal length. This is a 330mm lens setup, which, on a crop sensor DSLR, would be multiplied by 1.5.

[kacansas03]

Thanks--the 67 lens on a crop sensor only uses the sweetest of the sweet spot, so the Tele does not have much in the way of imperfection to magnify by a factor of 2. The result are images even to the corners with amazing IQ--I am overwhelmed. And the lens, a 330mm 5.6, will close focus down to 5.25 feet.



The tri-pod mount is built into the 67 to K-mount adapter. The Tamron 2x Tele is made for Full frame K-mount lenses. I am surprised by IQ too. Yes, focal length is focal length. This is a 330mm lens setup, which, on a crop sensor DSLR, would be multiplied by 1.5.

Again Wow. So that article I read was full of hooey. I thought so. I am thinking about a fast 300 mm 6 x 7, I hope they made one, mounted up in this manner. I would also need to get one of the better 2X TC but I am told the CPC is fair. Plus I need to get the K to 6 x 7 mount adapter. Oh and I suppose the money to purchase the gear. I can also dream of a 6 x 7 camera while I am at it with a wide angle lens.

[Spyder]

Again Wow. So that article I read was full of hooey. I thought so. I am thinking about a fast 300 mm 6 x 7, I hope they made one, mounted up in this manner. I would also need to get one of the better 2X TC but I am told the CPC is fair. Plus I need to get the K to 6 x 7 mount adapter. Oh and I suppose the money to purchase the gear. I can also dream of a 6 x 7 camera while I am at it with a wide angle lens.

I was considering that as well since about the only older long primes I tend to see around here are all for 6x7, and then I saw how much the 67->K adapter sells for.

[Jewelltrail]

dadipentak: I'll join that chorus: WOW!

Thanks!

kacansas: Again Wow. So that article I read was full of hooey. I thought so. I am thinking about a fast 300 mm 6 x 7, I hope they made one, mounted up in this manner. I would also need to get one of the better 2X TC but I am told the CPC is fair. Plus I need to get the K to 6 x 7 mount adapter. Oh and I suppose the money to purchase the gear. I can also dream of a 6 x 7 camera while I am at it with a wide angle lens.

Yes, you have some choices for a fast 300 in 67 mount. But this would be the one to hop on--not sure of the odds of finding this on Ebay for under a hundred bucks though. Pentax Lens Review and Specification Database - SMC Pentax-M* 67 300mm F4 ED [IF]

Can you post a link to the article? I got the Tamron MC7 BBAR SP 2x Tele for free, in an Ebay deal where i bought a Sigma 400 5.6. The 67 to K-mount adapter I picked up for use with all my 67 lenses--well worth it to me. The 67 165mm 2,8 I bought, shipped, for under $90 in an Ebay deal. Oh, the lens has the best bokeh of any lens I have used to date--for example:

[kacansas03]

I somehow found it in Google when I was trying to make up my mind in 2008 whether to buy into the Pentax digital or into the Panasonic micro 4/3's system. I doubt I could find it again. What I was attempting to understand was this advertising that tells a buyer that a 200 mm lens on that 1/2 sized sensor is like having a 400 mm lens mounted. This was a big factor for me since I like super long telephoto, fast "normal" for snapshots, midrange zooms for action snapshots, wide angle for scenery plus Macro. Now I know enough to realize that Pentax will be able to give me all of these without my having to settle for less desirable results in wide angle(not fisheye), a big design challenge for micro 4/3's. Much easier for Pentax and I know that focal length is always the same no mater the FOV.

[Jewelltrail]

Spyder: I was considering that as well since about the only older long primes I tend to see around here are all for 6x7, and then I saw how much the 67->K adapter sells for.

How much did it sell for? I am more than happy for what I payed for my adapter--well worth it. Not only have I used it for several 67 lenses, but I also love the fact it comes with a tripod mount.

[Spyder]

How much did it sell for? I am more than happy for what I payed for my adapter--well worth it. Not only have I used it for several 67 lenses, but I also love the fact it comes with a tripod mount.

It sells for about £200 here ($300ish US). If I already had a lens or two to use it might be worth it, but when I add the cost of the adapter onto a lens they suddenly don't seem such good value any more given what else I have in my bag.

It's the same reason I haven't picked up any M42 lenses yet, the Pentax adapter costs more than the lenses do (and I've heard too many horror stories about the cheap ebay ones ).

Or maybe I just have unrealistic expectations.

[Jewelltrail]

Spyder: It sells for about £200 here ($300ish US). If I already had a lens or two to use it might be worth it, but when I add the cost of the adapter onto a lens they suddenly don't seem such good value any more given what else I have in my bag.

It's the same reason I haven't picked up any M42 lenses yet, the Pentax adapter costs more than the lenses do (and I've heard too many horror stories about the cheap ebay ones ).

Or maybe I just have unrealistic expectations.

No, your expectations are reasonable--$300 us is way too much. I paid around $70 us. I bought it more than a year ago, off an Ebay seller, but can't remember who. But this one looks like mine: Pentax 67 lens Adapter to Pentax PK with tripod mount - eBay (item 400115159525 end time May-12-10 21:45:12 PDT)
Actualy here is another one which looks the same to me: http://cgi.ebay.com/Pentax-67-lens-Adapter-Pentax-PK-tripod-mount-/310214866...item483a3f3627
Where are you located? I can assure you the adapter I got off of Ebay is of excellent quality.

[Spyder]

They don't call it 'rip-off Britain' for nothing.

Although to be fair that was for the actual Pentax adapter rather than a 3rd party one.

Actualy here is another one which looks the same to me: http://cgi.ebay.com/Pentax-67-lens-A...item483a3f3627
Where are you located? I can assure you the adapter I got off of Ebay is of excellent quality.

There's a few on the UK ebay that have exactly the same picture set and description as the one you posted (so I have to assume they're the same) for a somewhat more reasonable price. Reasonable enough to be worth a punt so I'm ready next time a lens pops up for sale.

[Canada_Rockies]

They don't call it 'rip-off Britain' for nothing.

Although to be fair that was for the actual Pentax adapter rather than a 3rd party one.



There's a few on the UK ebay that have exactly the same picture set and description as the one you posted (so I have to assume they're the same) for a somewhat more reasonable price. Reasonable enough to be worth a punt so I'm ready next time a lens pops up for sale.

I use the Pentax M42 > K adaptor. All M42 screw mount lenses focus to infinity, something that is not true of the 3rd party adaptors that have a flange over the lens mount. The Pentax adaptor slips out of the mount with a thumb nail, it does not need a fiddly little tool, which for me is just something else to drop in the mud and lose. The Pentax adaptor threads never bind. Why cry about an extra 10 in the cost? You only need one of them, and it will last forever. The only moving part is the catch.

Perhaps it is just me, but I find it incomprehensible that someone would buy cheap junk to put on a camera that cost five times as much as my first car.

[Spyder]

Why cry about an extra 10 in the cost? You only need one of them, and it will last forever. The only moving part is the catch.

Perhaps it is just me, but I find it incomprehensible that someone would buy cheap junk to put on a camera that cost five times as much as my first car.

We were talking about 67->K adapters rather than M42->K adapters, but we get ripped off for those here too. A new one is £65 from a reputable shop (which is extortionate given what it is) compared to £6-7 for the nasty Chinese ones.

I will eventually win an auction for a 2nd hand one though, I'm in no rush.

[Jewelltrail]

Spyder: A new one is £65 from a reputable shop (which is extortionate given what it is) compared to £6-7 for the nasty Chinese ones.

There are some junk M42 adapters on Ebay, but there are some good ones too. For about $15, I bought a Bower made adapter on Ebay. It came with that silly little tool to dismount it, but here is what I do--has worked for over 2 years for me. It is the one and only M42 adapter I have ever owned and it works great on all my 7 or 8 M42 lenses.

Just take the clip which locks the adapter into the body and gently pull it off with a thin pair of needle nose pliers. Then, screw the adapter on the M42 lens you are going to mount. Now you an use the M42 lens like a K-mount. The only catch is you rely on a friction fit to hold the lens on the body. However, I have been doing this for years with no problems--all for a $15 investment. You need to screw the adapter onto the M42 lens just tight enough so that the friction mount of the bayonet-adapter releases before the adapter starts to un-thread from the M42 lens.

It sounds complicated--it is simple. If you wish, you can use a thread locking compound to make the M42/K-mount lens more permanent--but then you need more adapters for your other M42 lenses.