zenit lens help

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mtnbowhunter
Posts: 115
Joined: 12 Jun 2013, 06:05
Location: WA, USA

zenit lens help

Post by mtnbowhunter » 04 Jul 2015, 21:30

I have ZENIT IR 1.6/85 lens from a zenith night vision spotter.
IT has an M42 mount and the rear lens sticks out slightly beyond that.
I have tried it on an old Pentax SLR thru the lens viewfinder camera body and I can not get the rear lens close enough in (it hits the mirror) to focus to infinity.
so the question is for you ZENIT lens users, if I use a bare board camera behind this lens will I be able to get it close enough for the camera/lens to focus at infinity?

Paul1961
Posts: 241
Joined: 17 Jun 2013, 11:19
Location: Melbourne, Australia

Re: zenit lens help

Post by Paul1961 » 05 Jul 2015, 10:35

Cant see why not, it must form an image behind its rear lens at some distance. You will just need to make sure whatever mounting system you're using sets the board camera to the correct distance. Perhaps you need to provide some detail as to how you intend on mounting the board camera to your lens - are you using a M42 to C mount adapter etc.

Regards,

Paul

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lenny.sch
Posts: 307
Joined: 24 Sep 2012, 06:40
Location: Sydney Australia

Re: zenit lens help

Post by lenny.sch » 05 Jul 2015, 14:23

I haven't personally tried one behind a Film SLR Camera with Mirror but I do remember reading that there are quite a few lenses that won't work with them as they hit the mirror but they then stated they are fine in the digital models because there is no mirror.

ATB.len

mtnbowhunter
Posts: 115
Joined: 12 Jun 2013, 06:05
Location: WA, USA

Re: zenit lens help

Post by mtnbowhunter » 05 Jul 2015, 15:24

that is what is happening - the lens hits the mirror and still is not at infinity focus
I was curious if the focus distance in a film slr camera when using a lens has any bearing if that distance would be the same using aboard camera.

I will eventually make up a jig and mount a board camera that can be easily moved to check out the correct distance to achieve focus with the lens

I was just grasping that some of the members here may of had/have experience with this model Zenit lens, 1.6/85.

Jirka
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Joined: 04 Jun 2014, 15:31
Location: Rijnland (Holland), Sudetenland (Bohemia)

Re: zenit lens help

Post by Jirka » 05 Jul 2015, 16:25

Although these lenses have M42 thread, they are not designed for and will not work with SLRs, because their flange distance is extremely short and they protrude very much behind the flange/thread. I also believe their image circle is not sufficiently large for APS and larger sensors.

And yes, the flange distance is the same regardless of what you mount that lens on.

mtnbowhunter
Posts: 115
Joined: 12 Jun 2013, 06:05
Location: WA, USA

Re: zenit lens help

Post by mtnbowhunter » 05 Jul 2015, 17:45

so if the big brother 1.5/100 ZENIT lens also has the rear lens protruding well behind the shoulder/threads perhaps then the focal length to the board camera/sensor would be the same as the smaller 1.6/85 lens??

does anyone have that distance for the 1.5/100 lens?

Jirka
Posts: 680
Joined: 04 Jun 2014, 15:31
Location: Rijnland (Holland), Sudetenland (Bohemia)

Re: zenit lens help

Post by Jirka » 05 Jul 2015, 18:25

Yes, the chance that their flange distance is the same, is pretty high.

BTW: these lenses are not very good for photography anyway.

mtnbowhunter
Posts: 115
Joined: 12 Jun 2013, 06:05
Location: WA, USA

Re: zenit lens help

Post by mtnbowhunter » 05 Jul 2015, 19:41

it is going to be used in a nv spotter, maybe in a new lens for photon xt.

JoeDirt
Posts: 47
Joined: 26 May 2018, 22:51
Location: Orygun

Re: zenit lens help

Post by JoeDirt » 10 Jun 2018, 01:53

I see a few of these lenses on ebay, so there is no way to get the correct focal length with a e700/EJ230? The title in the "sticky" say "Why the 85mm Zenit IR lens is not usable for DIY NV: viewtopic.php?f=29&t=12248"

All I have read is they dont work with mirrored camera...... Am I missing something? :crazy:

snipertez
Posts: 58
Joined: 01 Jan 2014, 10:20
Location: Devon, near Exeter

Re: zenit lens help

Post by snipertez » 11 Jun 2018, 06:15

JoeDirt wrote:
10 Jun 2018, 01:53
...... Am I missing something? :crazy:
3yrs by the looks :yawn: :mrgreen:

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