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Focal reducer/Speed booster adapter

for/Pentax PK K bayonet lens to Sony NEX mount 5 6 7 camera FS700 FS100

All metal structure, with excellent opticals (4 elements/2 groups, super multi-coated)
what it does:

•
reduce the focal length (by 0.72x wider)

•
Ex. 50mm lens on NEX with the adpater, eff. focal length is 50mm x 1.5(crop) x 0.72 = 54mm

　
•
effectively increases the maximum aperture of the lens by 1 stop



•
(in other words, under the same aperture, you can use faster shutter speed (by 1 stop).

　 what it does not:
there is no electronic integration, no auto fucusing

(you still need to manually focus your lens and aperture, etc.)

Focal Reducer Speed Booster Adapter Pentax PK K to Sony NEX 3 5 6 7 FS700 FS100 | eBay

[SyncGuy]

Ah.... More good things are to come it seems!

I'll wait it out for another 6 months. Most definitely there will be more of other makers from China...
Which will mean, lower prices!

[devorama]

Link to a quick review:

Gary Barnes | Photographer

[kuuan]

great, thank's a lot for that! I can't wait for your samples!
I have great hopes for this adapter, made by a company with a record of making decent optics why should it not perform just as well as the M.bones

Do you have a M42>Pentax K adapter? If so I'd be most curious to find out if it works on the focal reducer! I am afraid though that the focal reducer most likely won't have a lock for the M42 adapter and therefore the M42 adapter will rotate which makes use difficult unless one finds a way how to lock it in place.

Just found out that my statement that the K mount needs to have a lock for the M42 adapter to lock was wrong. That means that I am quite positive that a M42 adapter will work on the Pentax K lens turbo. However just how well it will work does depend on the exact make of the K mount on the lens turbo!

came to this conclusion after checking again the fit of my original Pentax M42 > K mount adapter. On a Pentax body it locks fine, on my Pentax K > Sony E mount adapter it does have a play but will be tight once the M42 lens is mounted. I could not make the M42 > K adapter lock in my K > Leica M adapter ( for my Ricoh GXR ) but found out that it does lock fine if I first mount the M42 > K adapter on the M42 lens and then lock it into the K > M adapter, which, if one wanted to change the M42 lens used, is less practical. Sounds confusing but it isn't really..

[kuuan]

Link to a quick review:

Gary Barnes | Photographer

looks great, thank you for posting this ( and sorry that my last post had removed you post, which is much more important than mine, to be the last answer in this thread, I must have written it while you posted )

[NickLarsson]

Link to a quick review:

Gary Barnes | Photographer

Thanks!

[jogiba]

Congrats,

I think the 3N is a fantastic value. Especially at $50 off right now, for the kit. I've been trying to convince my coworker to get one.

I ended up ordering the FD mount version. Some people on DPReview have already received their adapters and are getting good results. It seems there are some internal reflections, but overall the quality is there. I don't mind a bit of flare and ghosting, it can look cool sometimes.

I ordered it from Roxsen so I will see how my fast F1.4 lenses that I use on my full frame Sony NEX-VG900 like my 24mm Rokinon PK mount works at F1.0 .

[Sliver-Surfer]

Hello all I received my Booster from Jinfinance and it is the same as the Roxsen(Zohngyi): I got it safe and sound...didn't even get billed by customs. Build seems very nice my after market m42-K ring seats well and secure and K lenses fit well even my 17mm Vivitar with overly long Aperture Tab. Now Im going to go shoot some pictures.
Can I just say the one item I think will most benefit from this adapter is my asahi pentax 55mm stereo adapter, that thing needs the extra light and full frame.

[kenafein]

I ordered mine from MXcamera. It's still not here, though they said 4-5 days. I hope to see it soon. I'll be interested to see your sample shots.

[jogiba]

My tracking # from Hong Kong Post says " Acceptance 2013-05-23, 15:51:00 " so that was yesterday since it is 5:04AM May 24 in Hong Kong now.

[Sliver-Surfer]

Heres some shot with my Tamron 2.5 135mm adaptall all at f2.5 overcast..I have the day off tomorrow so more shots will come. LOL the 2nd from last was funny my daughter had to "go"
My Impression is..This thing is a Keeper go buy it. I can actually use my 135mm indoors now. What do you want to see next :I have Lots of M42 taks and Pentax k mounts

[jogiba]

That is great news and I might even try it on my SMC Pentax-M* 300mm F4 .

[SyncGuy]

Of coz it's a keeper.. Now your APSC crop factor bas become x1.1 instead of x1.5! Woohoooo!

[jogiba]

Shipment Activity Location Date & Time
-------------------------------------------------------------------------------------------------------------------
Depart USPS Sort Facility SAN FRANCISCO, CA 94128 May 25, 2013
Processed through USPS Sort Facility SAN FRANCISCO, CA 94128 May 25, 2013 10:32 pm
Processed Through Sort Facility ISC SAN FRANCISCO (USPS) May 24, 2013 8:41 pm
Origin Post is Preparing Shipment
Processed Through Sort Facility HONG KONG AIR MAIL CENTRE, HONG KONG May 24, 2013 10:27 am
Acceptance HONG KONG May 23, 2013 3:51 pm

I should be getting it soon.

[Sliver-Surfer]

Played with my Pentax Asahi m42 stereo adapter now quite usable with the booster
first pic is original second is modified for cross eyed 3d viewing (look at the images cross eye until you see 3 images, the Middle image will be 3d)(if it doesn't feel right tilt your head back and forth until it lines up)

The host lens is a 55mm f1.8 super takumar m42

[Sliver-Surfer]

Tamron Adaptamatic 135mm f2.8 at f4 in low light 1/125s 800iso. the shadow in the forground is a kid getting in my way