AF confirmation adapter for A-mount manual lens help/advice

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Pirate
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AF confirmation adapter for A-mount manual lens help/advice

Unread postby Pirate » Sun Jan 31, 2010 12:51 pm

Ahoy!

Not sure if I'm posting in the right forum, so if incorrect could mods please move.

My question is in relation to the Samyang/Falcon (or other derivitive) 8mm f/3.5 fisheye lens which is MF in a-mount.

Is there a focus confirmation adapter on the market and if not, does anyone know if it's possible to adapt this specific lens?

The reason I'm asking is that the old 'peepers' are a little bit 'iffy' and as I have to wear an ocular vision enhancement aid (spectacles), I don't trust my 'mince pies' (eyes) any more for precise manual focus.

Any guidance appreciated.

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Re: AF confirmation adapter for A-mount manual lens help/advice

Unread postby David Kilpatrick » Sun Jan 31, 2010 1:57 pm

You don't need AF or confirmation. The focus scale is sufficient, as the depth of field is huge. But you can order a chip from James Lao, it could be a messy job glueing it to the Samyang mount.

http://eadpt.cn/eadpen.htm

David

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Re: AF confirmation adapter for A-mount manual lens help/advice

Unread postby Pirate » Sun Jan 31, 2010 3:15 pm

David Kilpatrick wrote:You don't need AF or confirmation. The focus scale is sufficient, as the depth of field is huge. But you can order a chip from James Lao, it could be a messy job glueing it to the Samyang mount.

http://eadpt.cn/eadpen.htm

David


Ahoy David!

Thanks for the info and link. I was just concerned that because of my less than perfect eyesight, I wouln't be getting the subject in focus, hence the AF confirm question. One would assume then that the lens will pretty much get everything in focus most of the time due to it's infinity focus cabability and DoF (or am I off tangent)? Maybe I misworded my initial question. Is it possible (or needed) to have focus confirmation? Secondly, I assume because of the lack thereof, the SSS on A700 will not function.

It still looks like a teriffic bit of kit, but I would hate to spend all day shooting only to find images OOF or the like. Anyway, before I hit the 'BIN' button, I wanted to cover all the bases.
Last edited by Pirate on Sun Jan 31, 2010 5:49 pm, edited 1 time in total.

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Re: AF confirmation adapter for A-mount manual lens help/advice

Unread postby David Kilpatrick » Sun Jan 31, 2010 3:28 pm

At f/2.8 and very close, you may need AF confirmation, but the scale focusing is almost as useful. Trust me, you can not focus any more accurately on the screen or with AF, than the scale. At f/5.6, which is the aperture the AF sensors will 'see', depth of field extends for metres - literally. Your AF confirm light will be on all the time while you change focus between 50cm and infinity!

Also, SSS is not so much needed either. You can hand-hold an 8mm lens at 1/15th without SSS.

David

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Re: AF confirmation adapter for A-mount manual lens help/advice

Unread postby Birma » Sun Jan 31, 2010 4:20 pm

Interesting stuff - thanks to Pirate and DK for providing the means of illumination for the rest of us. I'd be interested to see some of your results with the A700 when you get hold of the lens.
Nex 5, Nex 6 (IR), A7M2, A99 and a bunch of lenses.

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Re: AF confirmation adapter for A-mount manual lens help/advice

Unread postby Javelin » Sun Jan 31, 2010 4:48 pm

oh man I was sure thinking David had lost his mind there. I read 8mm but my poor old brain registered 85mm .. as in the samyang f1.4 and I thought how can the DOF be so big af F2.8

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Re: AF confirmation adapter for A-mount manual lens help/advice

Unread postby harvey » Sun Jan 31, 2010 5:04 pm

Pirate wrote:Thanks for the info and link. I was just concerned that because of my less than perfect eyesight, I wouln't be getting the subject in focus, hence the AF confirm question. One would assume then that the lens will pretty much get everything in focus most of the time due to it's infinity focus cabability and DoF (or am I off tangent)? .

You have it right.

I have a similar problem to you. I was so happy when the 7000 came out as I found it hard to focus on the Pentax ME Super with split prism.

If you can read the marks on the lens then set the lens to 1m and everything will be in focus at least from 50cm or so in the worst case to infinity.
So unless you are taking pictures very close up I don't think you will have problems with focus due to the huge depth of field.

Harvey
Last edited by harvey on Sun Jan 31, 2010 11:56 pm, edited 1 time in total.

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Re: AF confirmation adapter for A-mount manual lens help/advice

Unread postby Pirate » Sun Jan 31, 2010 5:51 pm

Thanks everyone. Help and guidance appreciated.

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Re: AF confirmation adapter for A-mount manual lens help/advice

Unread postby Pirate » Sun Jan 31, 2010 7:42 pm

Ahoy!

FYI, I've taken the plunge and bought the Samyang version from a Polish retailer via evilBay, though I see prices rising for the Samyang via Europeean sellers but Falcon via UK remains under £180.00.

After a trip to the opticians next week, I really hope you guys are right, else I've just p****d away a fair amount of wedge.

I'll be in touch once it arrives if anyone is interested. I've never tried one of these lenses, and with my dodgy eyesight, this could get messy!
Last edited by Pirate on Wed Feb 03, 2010 1:18 pm, edited 1 time in total.

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Re: AF confirmation adapter for A-mount manual lens help/advice

Unread postby David Kilpatrick » Mon Feb 01, 2010 12:00 am

The Polish distributor is very reliable, perfect paperwork and shipping. They are one of Poland's major photo stores.

David

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Re: AF confirmation adapter for A-mount manual lens help/advice

Unread postby Greg Beetham » Wed Feb 03, 2010 1:11 pm

I've just been reading a review on this lens....don't worry Pirate you haven't done your dosh...apart from being VERY fishlensy (the usual distortion), they think it's quite ok, especially for the money. And you don't even have to worry about no AF and dodgy eyesight overly much, just set the lens focus at 0.6M @ f5.6 (or f8 probably even better), and everything is in focus from 0.29M out to infinity.
Greg

http://www.lenstip.com/160.1-Lens_review-Samyang_8_mm_f_3.5_Aspherical_IF_MC_Fish-eye_Introduction.html

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Re: AF confirmation adapter for A-mount manual lens help/advice

Unread postby Pirate » Thu Feb 04, 2010 7:36 pm

Greg Beetham wrote:I've just been reading a review on this lens....don't worry Pirate you haven't done your dosh...apart from being VERY fishlensy (the usual distortion), they think it's quite ok, especially for the money. And you don't even have to worry about no AF and dodgy eyesight overly much, just set the lens focus at 0.6M @ f5.6 (or f8 probably even better), and everything is in focus from 0.29M out to infinity.
Greg

http://www.lenstip.com/160.1-Lens_review-Samyang_8_mm_f_3.5_Aspherical_IF_MC_Fish-eye_Introduction.html


Ahoy!

Lens arrived today. I put A700 in M mode, experimented with the aperture at f/5.6 and f/8 and set the distance scale to 0.3m and +1 and +0.7 exposure on the camera (as suggested by the user documents). Only fired a few on-board flash shots indoors, but all look OOF to me :o(

I can't see how you can confirm-focus the lens on anything, only set the distance scale, point and shoot.

I'll test fire again tomorrow hopefully outside. Using on-board flash with fisheye indoors just gives you a big black ring!

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Re: AF confirmation adapter for A-mount manual lens help/advice

Unread postby David Kilpatrick » Thu Feb 04, 2010 8:10 pm

0.3m? I am sure if you set the lens to f5.6 and only 30cm distance, stuff will out of focus. Try 3m distance for outdoors, 2m distance for indoors. You can only get focus confirmation if you add a chip to the lens, this can either mean glueing or hacking up the mount a bit, and the chips cost about £40 - it should not be needed.

Also, do not set any exposure compensation. Set A mode and spot metering for circular image fisheyes.

David

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Re: AF confirmation adapter for A-mount manual lens help/advice

Unread postby pakodominguez » Thu Feb 04, 2010 8:20 pm

David Kilpatrick wrote:You don't need AF or confirmation. The focus scale is sufficient, as the depth of field is huge. But you can order a chip from James Lao, it could be a messy job glueing it to the Samyang mount.

http://eadpt.cn/eadpen.htm

David

Hi David,

Can you show a picture of what you've done with your Samyang 85 f1.4? They annonced a 35mm f1.4 for the end of this year and I'll be interested in a lens like that, specially if Samyang start chipping their lenses -otherwise a custom chipping is an option...

Regards
Pako
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Re: AF confirmation adapter for A-mount manual lens help/advice

Unread postby David Kilpatrick » Thu Feb 04, 2010 9:28 pm

My conversion was such a mess I don't really want to post the pix. It works, and I did a page in the magazine about it, but my grinding wheel ripped into the soft mount instantly and pretty much destroyed one flange. I did not even need to, a different chip would have fitted without touching the mount. Now that is what people are doing, using the chip which looks as if it won't fit, but does.

David


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