rcdovala

I posted the following but since I had included images to illustrate my point, the Admin moved it to a section not readily visited:

"I was playing around with my D600 using an older Tamron 1.4X lens extender from my film days. It is a model MC4. It actually performs better on my digital cameras than it did on my film cameras. And that is primarily due to the fact that digital images can be sharpened which makes what would have been a marginal image on my film cameras an acceptable image on my digital cameras. None of that is surprising. But what is surprising is that when I attached one of my DX lenses to the extender, I discovered that the lens/extender combination allowed for full coverage of the sensor. Initially, I thought that the D600 was in the crop mode but it was not. The next thought that came to my mind was that this was probably an anomaly specific to the lens that I had mounted. But that was not the case either. Every DX lens that I mounted on the extender covered the entire sensor with no vignetting that I could see. I've attached three images as an example. These are not works of art so critiquing is not required. We've had a horrible drought in California and my backyard still has not recovered. Also, the three images have been downsized to make their file size manageable so you'll have to take my word that these images are from the full sensor. What makes this exciting for me is that my Tamron 11-16mm f:2.8 DX wide angle zoom becomes a 15.4-22.4mm f:4.0 lens on my Nikon D600. Has anyone else observed this behavior either with a Tamron extender or any other brand of extender?"

I'm reposting it without the images just to get this information out to other UHH members. I have not seen this topic discussed before and I hope that you find it useful.

Apaflo Loc: Anchorage, Alaska

The original thread did have useful and interesting discussion. It was moved to the Gallery. Here is a link to the original thread to allow easy reading of the original exchange.

http://www.uglyhedgehog.com/t-510649-1.html

rcdovala

Thank you. I couldn't find where it was moved.

repleo Loc: Boston

Interesting posts (read both). Does anybody know if there is an equivalent 1.5X extender available for the Sony E to FE mount?

Apaflo Loc: Anchorage, Alaska

There are various adapters to the Sony mount. Any appropriate teleconverter and mating lens could then be used.

Gene51 Loc: Yonkers, NY, now in LSD (LowerSlowerDelaware)

You always run the risk with shorter focal lenses that the front element of the TC touches the rear element of your lens. TCs were not intended for use with anything shorter than a medium tele lens.

Bill_de Loc: US

That is pretty cool. I can't believe this is the first I have ever heard of this considering all that is written on DX vs FX lenses.

Thank You!

--

rcdovala

I believe that this is more applicable to FX lenses on lens extenders than DX lenses on lens extenders. I had no problems mounting any of my lenses including the Tokina 11-16mm f:2.8.

camerapapi Loc: Miami, Fl.

The only DX lens I have that I use with my D610 is the Nikon 12-24 f4 that I use without vignetting between the focal lengths of 16-f24 mm. I do not use tele-converters.

imagemeister Loc: mid east Florida

I guess everyone now might understand what a TC/E actually does - it spreads the image light cone out ( bigger) - that is how it makes magnification -and- looses light. There are very few positive applications for it tho.....

rcdovala

What is your basis for stating that there are few positive applications for it? This may be your opinion but it is not supported by facts.

lamiaceae Loc: San Luis Obispo County, CA

I took a look at the original post as well. I had not noticed the effect with my Pentax cameras but then I was not looking for it either. Seeing as I don't have a FF Pentax DSLR but I'll give it a try with a film camera. I do know that my DA and DA* lenses do not cover a FF Film format. I'll report back what I find.

rehess Loc: South Bend, Indiana, USA

I wonder if this being film TC affects anything.

lamiaceae Loc: San Luis Obispo County, CA

OMG (Said slowly)! I just found out two interesting things due to this post. Yes, 1.4x, 2x, and 3x extenders allow my CF (APS-C) Pentax K-mount lenses to be used on a Pentax FF body (K-1 and later) if I ever buy one. Yes, my Pentax digital CF lenses will cover a 35mm Film format when used with a tele-extender. Cool, so my smc-Pentax-DA* 16-50mm f/2.8 Zoom could be used as a "22.4-70mm f/4" on a FF or Film camera, or "32-100mm f/5.6" Zoom Lens. That was the expected finding. But in playing around with my digital lenses I also found that my smc-Pentax-DA 35mm f/2.8 Macro Limited lens on its own cover both APS-C and FF sensors. That was not expected. I had heard that some of the DA* lenses with longer focal lengths do cover both formats as well.

Being able to interchange lens formats this much is at least one thing Pentax has over Canon and even Nikon. From what I read Nikon DX are DX covering lenses only. Though as we've seen here using an extender can allow FX body use as well. Yet many higher end Pentax "digital" lenses have been both "DX" and "FX" all along! Who knew? I've of course been using my vintage Pentax film lenses on my digital cameras as well.

Apaflo Loc: Anchorage, Alaska

In addition to TC's, the exact same optical configuration, known as a Barlow Lens, is used in most telephoto lenses, in most telescopes, and often in microscopy.

It has MANY uses.