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The last of the "Three Amigos", these c-mount TV lenses were sold in the 70s under a variety of names: Cosmicar, Concord, Ampex, General Electric, and others. Generally better performers than the cheap cctv lenses now sold under that name.

Here is an example of an image at f4 (optimum):



Here is at f1.4:



Here are the three of them together (25mm f1.4, 50mm f1.4, 75mm f1.9):



There are two versions of each focal length, one with f1.4 maximum and one with f1.9 or 1.8 maximum. They all appear to be of the same design, I got mine for $40-$60-$100 on ebay. There is a black variation of these lenses as well, it may have a different design. I found them to be almost as sharp as the 06, and a little less contrasty, with better bokeh. They all have a nice glow wide open. Not shown are the hoods, the 25mm takes a 35.5mm thread, the 50mm takes a 40.5 and the 75mm takes a 46mm.

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Last edited by Unregistered User; 06-01-2018 at 05:01 PM. Reason: more info

[Phenix jc]

Samyang 7.5mm 3.5
Minolta MD 250mm 5.6 mirror
Leica Telyt 400mm 6.8
on Q7 :

m43 lens to Pentax Q adapter - PentaxForums.com

[kwb]

Lens table was updated. Cipher, Phenix jc, thank you for your submissions!

[Piotrek K]

Tamron CCTV 16/1.4. Modern lens, very suitable for the Q. f 1.4 is OK for black and white, f 2 really good , f 4 very good for landscapes (on the Q/Q10 at least), I use f 5,6 for macro-ish images. Some distrotion, but easy to correct. There are some variants of Tamron 16 mm CCTV lenses, mine is TAM 25-HB/12, I believe.

[kwb]

In the spirit of helping to reach 40000 posts this month, I updated the lens table again.
Piotrek K, thank you for your submission.

Minor bug fix in the table generation script means that lens names with double quote, e.g. Keystone CINE 1/2" f2.5 and Meyer-Görlitz Orestor 135mm f2.8 "Bokeh Monster" and such, are now sorted in correct order. They used to be listed earlier than the names without double quotes.

[Piotrek K]

Tamron 75/3.9 CCTV lens











This lens is sharp at minimum aperture and quite easy to focus.

[kwb]

... and I updated the table yet again, thanks Piotrek K!

[buzzinhornet]

We were discussing the possibilities of stopping down the 110 70mm lens with a disc on the front in another thread.
Pentax Auto 110 lenses for the Q - Page 2 - PentaxForums.com
So I thought I would have a go.
The disc is black paper cut to fit in the 49mm filter thread of the lens and held in place by the lens hood.
I used a cheap panel steel circle cutter in my drillpress.
I removed one of the blades and sharpened up the other.
And clamped the black paper on top of a cutting board onto the base of the drill.
Cut the centre first and cut the outer ring without moving the paper.
I suspected that even wide open the lens used only the centre 25mm of the front lens.
So I cut one disc with a 25 mm aperture and the other as small as the cutter would go which was about 19 mm and should be about one stop slower than 25mm.
Test image is a ruler placed on mattboards-- one light grey -- one dark grey.
the camera is at about 45 degrees to the subject to display DOF on the ruler.
The 2 tones of grey was to create a 2 spiked histogram to compare exposure.
The results are screenshots with histogram included and turned on their side to better fit the format here.
The result show no difference in exposure between the 25mm disc and the lens wide open, confirming my suspicions the lens doesn't use the outer glass.
The 19mm disc is indeed one stop slower but only slightly sharper.
I will leave the 25mm disc permanently there to keep light from scattering off the unneccessary extra glass.
The last image is there to remind us that the lens can not make a decent image unless it is attached to a camera and used!

Does the front mount disc work much better than using an aperture disc in the adaptor?

[reh321]

The last of the "Three Amigos", these c-mount TV lenses were sold in the 70s under a variety of names: Cosmicar, Concord, Ampex, General Electric, and others. Generally better performers than the cheap cctv lenses now sold under that name.

Before purchasing one, how do you differentiate between these and the modern cheaper, lower quality versions??

Before purchasing one, how do you differentiate between these and the modern cheaper, lower quality versions??

They have the "satin chrome finish", meant to look like an Angeneuix, they all have markings like the ones in the photos above, with a reddish-orange indicator "diamond". They have multiple blades in the iris: 8 blades for the 25mm, 10 blades for the 50 and 75mm.


The newer ones are black, generally made of plastic. Some have as few as three iris blades! They aren't terrible, but generally don't have as good edge to edge sharpness.


There are also older Cosmicars that have a black barrell, made of metal and are similar in construction to the chrome ones, I don't know how they compare.

[barondla]

Thanks to everyone adding to this database and to kwb for keeping it updated.
Thanks
barondla

This is a c mount lens made by D.O. Industries, it appears to be of 1970s vintage. Naturally its focal length and speed make it quite hefty, about the same size as a DA 18-55 and weighing noticeably more:



It is well made, with 8 aperture blades and smooth handling. It is quite sharp, even wide open at f1.3 (some purple CA will be seen on out-of-focus areas):



When stopped down to f4 it gives quite respectable results:




While it lacks auto focus, it seems to be an interesting option for the Q system, considerably longer than the 06 and no slouch in resolution. A 350mm f1.3 lens in FF would be a monster!

Note: infinity focus is in-between the two different c mount adapters I have, I ended up shimming the thinner adapter

while the thicker one wouldn't allow infinity focus without modification.


See posts #1091 and #1093 in this thread to see similar shots by the Ampex/Cosmicar 75mm f1.9.

[barondla]

This is a c mount lens made by D.O. Industries, it appears to be of 1970s vintage. Naturally its focal length and speed make it quite hefty, about the same size as a DA 18-55 and weighing noticeably more:



It is well made, with 8 aperture blades and smooth handling. It is quite sharp, even wide open at f1.3 (some purple CA will be seen on out-of-focus areas):



When stopped down to f4 it gives quite respectable results:




While it lacks auto focus, it seems to be an interesting option for the Q system, considerably longer than the 06 and no slouch in resolution. A 350mm f1.3 lens in FF would be a monster! I'll be doing some real-world available light tests and will publish them later in the regular Q section.

Note: infinity focus is in-between on the two different c mount adapters I have, I ended up shimming the thinner adapter

while the thicker one wouldn't allow infinity focus without modification.


See posts #1091 and #1093 in this thread to see similar shots by the Ampex/Cosmicar 75mm f1.9.

Super looking results!
Thanks for sharing,
barondla

[GUB]

This K series mirror zoom is about f12 at 600mm so we are into diffraction country well and truly. Still I think I am still ahead of using it on the K1 and cropping it but that comparison would be a good test one day. Saved in raw and pped to the best of my abilities. No cropping.

[barondla]

This K series mirror zoom is about f12 at 600mm so we are into diffraction country well and truly. Still I think I am still ahead of using it on the K1 and cropping it but that comparison would be a good test one day. Saved in raw and pped to the best of my abilities. No cropping.

Neat lens entry GUB. Can't be easy to shoot with on a Q. You achieved better results than I expected. Good job.
Curious how this lens performs on the K1 uncropped? Would you rate it decent or better?
Thanks,
barondla