Fujian 25mm f1.4 CCTV "toy" lens

Last thursday, my brother (ty Crikou !) brought me a very exciting present: 3 CCTV "toy" lenses (25mm f1.4, 35mm f1.7, 50mm f1.4), coming together with a m43 mount adapter and some macro rings.

As you probably know, such very cheap C-mount lenses are initially intended to be used as security cameras, and even if they are pretty fast, their optical qualities are obviously quite poor. They are nevertheless known as very fun to use, and after a few tests, I have to say that I completely agree with this statement !

I first tried to compare the 25mm lens with my Panasonic 25mm f1.4 lens to have an idea of how "bad" it was. As you can see here below, the CCTV lens has indeed very high optical defaults: the picture centre is quite sharp but as soon you go off centre, a lot of distortion appears, vignetting is very high, and - worse point probably - the picture becomes more and more soft if not totally blurred. Stopping down clearly improves the situation as far as softness is concerned, and a good compromise might be to shoot around f/4 to try to reach something that approaches standard-quality lenses.

       
Comparison at 25mm f1.4 (1/40, ISO200) using the Panasonic lens (left) & the CCTV one (right) & same OMD settings

But the point is probably exactely here: this lens can't clearly compete at all with standard high-quality lenses, but if you use its defaults in a creative way, it can doubtless give you a lot of fun while producing very characteristics & appealing pictures. Especially as the produced bokeh, distorted & blured, is quite unusual & therefore interesting from my point of view. I'm sure it can be very charming for portraits... if the face is centered ;)

Bokeh test in my home studio - Shot at 25mm f1.4 - Focus is made on the bass first fret

But where I became even more enthusiastic testing this 25mm CCTV lens was when I started to play with the macro rings to try to transform my camera into a kind of hand-made microscope ;)

    
My OMD-EM5 equipped with the CCTV 25mm lens (pictures from my phone):
normal mode (left) and "microscope" mode using 9 macro rings (right). Funny isn't it?^^

With this configuration, it have to confess that doing some macro shots was not very easy because the subject needs to be very close to the lens and that you need to step down near to the fully-closed diaphragm position to be able to recover a decent depth of field.

But with an adequate lighting, the results you can get are really amazing as you can see in the pictures below !! And the obtained true reproduction ratio exceeds 2:1 (i.e. a 35mm equivalent magnification factor of more than 4:1). For comparison, the macro capability of the Olympus 12-50mm kit zoom is 0.36:1 (0.72:1 equivalent 35mm). My home-made microscope is doing 5 times better !

I think I already love this toy lens \o/ 

Full-size (uncropped) shots of a 20€ bill (JPEG straight from the camera); the width of the real subject is 8mm, and the m4/3 sensor is 17.3mm long, leading to a more than 2:1 actual magnification factor (4:1 35mm equivalent)  

Same bill shot with the 12-50mm Olympus lens in macro mode; the actual magnification factor is here "only" 0.36:1 (0.72:1 35mm equivalent)