Taylor Taylor Hobson Cooke Anastigmat 12.5cm f2.5: First Session

e6filmuser

I have been searching for one of these since I saw a set of images from an f2.7 version in a photographic magazine. I had to wait many years, as they are rarely available. The lens has variable aperture, down to f16, but no focusing mechanism. Essentially, it is a bellows lens.

Just to make thing worse, the thread is M32 x 1.0mm. I have many adapters but I had nothing for this. So I contacted raf.camera dealer on Ebay who, after some discussion, made one for me. It is a thread converter, inner, female, thread M32, outer, male, thread M42. It arrived this morning.

I have had just a quickie session with it. Would it form an image and would it cover the sensor? On m4/3 both were OK. Straight onto the camera, via the new adapter and an M42-m4;/3 adapter, the FOV was 4mm wide at a working distance of ca 15mm. I tried a few shots at f16, with triple flash, hand-held. At that working distance the main problem was not to block the off-camera flash with the camera.

The subjects were those I have posted recently, shot through my Schneider HM40 setup. There are two slime moulds and the goblet-shaped mushroom with "eyelashes".

I am very pleased with the results. Whether they are up to those from the HM40, I suspect not, remains to be seen. I originally wanted the lens for lower magnifications that show here.

I want to see what the lens will do at higher magnifications. One option is to use tubes on the camera flange to set shorter extensions. The other, if it covers the frame, is to use my full frame A7R.

The images are uncropped.

Harold

e6filmuser

I have some shots on the full frame A7R. I will process and post today.

Harold

e6filmuser

Here are the images from the A7R full frame. The sun was low and there was some shadow, so I rally struggled at f16 to see anything at all. So the focus of them all could be better. These, as the first set, were all by (twin this time) TTL flash with the camera in manual mode.

The images have been process exactly the same as the first set (except there was less noise to remove). They have not been cropped. The most important result, for my purposes anyway, is that the frame is filled. Without the m4/3 crop factor the DOF is halved.

I am content that it is worth persisting with the evaluation of this lens for my choice of photographic subjects. It is only about the same size as a low power microscope objective so it could easily be added to a set of lenses.

Harold

GOLDENORFE

very interesting, good shots guys

e6filmuser

GOLDENORFE wrote: »

very interesting, good shots guys

Thanks. It means only so much with hand-held shots. I really didn't expect the lens (original application unknown to me) to cover the m4/3 sensor, let alone full frame. If the A7R batteries had retained their charge, I could have also done those shots with sunlight to help frame & focus.

The fungi are no longer suitable to make good images so I hope to find more subject material for further experimenting.

Harold