| |
PENTAX Helicoid Extension Tube K | | | | Reviews | Views | Date of last review | | 5 | 23,807 | Tue August 1, 2023 | |  | | Recommended By | Average Price | Average User Rating | | 100% of reviewers | $72.25 | 9.60 | | | | 
supersize
|
| |
| Author: | | New Member Registered: July, 2013 Posts: 2 | | Review Date: August 1, 2023 | Recommended | Price: $44.00
| Rating: 10 |
| Pros: | Build quality, versatility, adjustability | | Cons: | | |
Debated between this tube and the Auto Extension Tube K set until I found a pristine helicoid example on Ebay for about half the going rate of the tube set in similar condition. It doesn't provide quite the extension the tube set does, but the infinite adjustability more than compensates. Exudes 1980's Pentax pride of craftsmanship - I miss that, another reason to put this in the collection. I tried it out on my solenoid crippled K-50 with a Rokinon 135mm F2.0 manual focus lens for some informal tests, and for some reason, it provided perfectly exposed images with the camera in Live View mode and set on Program auto exposure. That's not supposed to happen, but it did, at serveral different combinations of extension and aperature. Not complaining! Overall, very pleased with this piece of vintage equipment, and will probably use it more than I anticipated with manually focused medium telephoto lenses.
| | | | | | | Veteran Member Registered: September, 2017 Location: Medellín Posts: 1,322 | | Review Date: December 31, 2019 | Recommended | Price: $60.00
| Rating: 10 |
| Pros: | Build quality, versatility, light. | | Cons: | No auto aperture - no problem. | |
Mine came with the case and it's awesome. I can use all kinds of adapted lenses on it. Even tiny enlarger lenses which fit right inside and focus to infinity with the right DIY or shop machined adapter. It works smoothly and you can't ask for better craftsmanship. Completely manual. Not a huge deal for macro and there are ways to stop down the aperture on a reversed lens before tripping the shutter. Nonetheless, sometimes, I just wish there were a second version with aperture lever like the Auto and non-auto Pentax extension tubes. Or at least a cable release socket. But this also means it's lighter than any of those hypothetical helicoids could ever be.
| | | | | Forum Member Registered: December, 2012 Location: Warsaw Posts: 83 | | Review Date: May 22, 2016 | Recommended | Price: $45.00
| Rating: 10 |
| Pros: | Compact package, easy to use, very usefull. Rare collector artefact. | | Cons: | No auto aperture coupler - but for macro it is not a big problem for me. | |
I got it with original pouch and original manual leaflet (very useful with lots of tables showing setting/distance/magnification ratio/ exposure factor).
I'm not a macro fan, so I got it more as a rare collector K-series item. I was very pleased to find, that it instantly turned my SMC-K 50mm f/1,4 and 55mm f/1,8 lenses into the tack sharp, powerful 1:2 to 1:1(!!!) macro tools.
Stop down metering works just like with Takumar lens attached - with f/1,4 - f/1,8 focusing is very easy - and when you got it - just close the aperture till shutter speed is still ok, and u'R done.
As I said I'm not a macro enthusiast - so for me some inconvenience is not spoiling the big fun of using this Pentax artefact.  | | | | | Senior Member Registered: December, 2009 Location: East Yorkshire Posts: 120
1 user found this helpful
| | Review Date: December 5, 2010 | Recommended | Price: None indicated
| Rating: 9 |
| Pros: | Compact and easy to use | | Cons: | Stop-down metering only | |
I was given the Helicoid Extension Tube by someone and did not have a clue what it was. After a bit of research I found out how you use it.
This must be the most useful close-up accessory Pentax has ever made. It is extremely easy to use and there are infinite settings between the maximum and minimum settings. Also you do not have to mess around constantly changing extension tubes.
The only down side is that stop down metering has to be used due to technical reasons (the tube rotates through 180 degrees).
These are very hard to find nowadays but if you do find one buy it, you won't regret it.
| | | | | | | Site Supporter Registered: October, 2008 Location: Vancouver, Canada Posts: 8,093
1 user found this helpful
| | Review Date: July 6, 2010 | Recommended | Price: $140.00
| Rating: 9 |
| Pros: | Very well built and compact. | | Cons: | Manual tube and expensive. | |
Pentax’s only variable extension tube for 35mm cameras. It works like the zoom function on a lens and you can adjust the extension anywhere from 26.5mm to 46.5mm. (20mm log helicoidal thread) At minimum extension the Helicoid is the equivalent of a No. 3 tube in the auto/manual set. Fully extended it is the equivalent of a No. 2 & 3 tube in the auto/manual set.
As this tube does not maintain the full aperture metering mechanism of the attached lens, you will have to use stop-down metering. Pentax does not recommend using the Helicoid on a Macro lens for this reason and recommends the Auto Extension Tube set instead. The other reason is the Helicoid tube and the Macro lens could both be used for adjusting the magnification ratio, so this would be cumbersome. Pentax recommends using the Helicoid extension tube with a lens in the 35mm to 200mm range or a reversed lens in the 28mm to 55mm range. (The 50mm Macro lens included, as it will be manual lens reversed)
This tube is very well built and is very small when closed to its minimum extension. It’s just too bad that it’s manual or I’d use it even more.
| | |
