the hiker Loc: San Diego

I am trying to find a 2x entender for a sony A mount A6500 with a Tamron 18 to 270 zoom lens. does anyone have one or know someone that wants to sell it? Please P/M the hiker if you know where I can get one. Thank You.

MDI Mainer

the hiker Loc: San Diego

Thank you for the info.

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

I wouldn't waste my money. You will lose autofocus, 2 stops of light - not that much of an issue with mirrorless and EVF for composition, anyway - but still an issue as far as image quality, and it may physically interfere with the rear of the lens causing damage to itself and/or the lens.

Teleconverters are intended to be used with very sharp optics, usually prime telephoto lenses or pro-grade zooms (70-200 F2.8, 200-400 F4, 70-400). The 18-270 is not a candidate.

https://www.sony-asia.com/support/resources/tw_TW/html/Compatibility/300342/Teleconverter_Compatibility.html

Ctrclckws

Agree with gene51 , for this lens, don't bother.
Teleconverters have glass elements and if the lens is not designed to be used with them, glass can contact glass, and that's not a good thing.

MDI Mainer

This alternative is from David Busch's Guide to the A65. While the A65's digital zoom is not as sophisticated as Sony's Clear Image Zoom on more recent model cameras, it does offer a reasonable alternative to teleconverters, and at no additional cost. (I assume you are referring to the older SLT A65, not the current MILC A6500)

While I have used some inexpensive 1.4x and 2x converters (Vivitar -- no longer in production) with this lens/camera combination, and I do not share the view of some that teleconverters are only to be used with fast, prime glass, I would describe the results as only marginally better than using the digital zoom function, and a lot more trouble. With digital zoom you do not degrade autofocus or light transmission. Nor do you have to take the lens on and off the camera body in the field to switch the zoom factor. But you are limited to shooting JPEG only and do loose pixels. So like so much in life and photography, it's a trade off judgement only you can make, and will be substantially affected by the use you want to make of the resulting images.

Here's the quote:

Shooting mode/Smart teleconverter. If the button [next to the AEL button to the right] has been set to Smart Teleconverter mode (in Setup menu 3 as described in Chapter 3): when using any JPEG Quality setting, press this button to zoom in and crop to the center of the image, producing a digital zoom function or “smart teleconverter.” Each time you press the button, you zoom from 1X to 1.4X to 2X, and then back to 1X (digital zoom off). Given the A65’s 24MP resolution, digital zoom is a practical way to pre-crop your image and still retain a reasonable amount of image detail. The function is not available when using Sweep or 3D Panorama, when using the Focus Magnifier feature (described below), or Smile Shutter is activated. It’s also disabled when using RAW or RAW & JPEG formats, and when shooting movies. This setting is “sticky” and remains active until you turn the camera off.

Busch, David D.. David Busch's Sony Alpha SLT-A65 Guide to Digital Photography (David Busch's Digital Photography Guides) . Cengage Learning PTR. Kindle Edition.

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

Rebuttal is in order.

Sony's own page, which I linked to, only shows the 135, 300mm, 500mm, 70-200 and 70-400 as being compatible with the 1.4X with autofocus only being available to the F2.8 and the F4 lenses, and the 2X leaving out the 125 F2.8 and the 500mm F4 from the list that can autofocus. And where manual focus is not available, the viewfinder doesn't even show focus acquisition.

I've tested Clear Image Zoom and Smart Teleconverter against good post processing technique with cropping, and found the in-camera versions to produce more artifacts. With Clear Image Zoom, most AF functions are missing leaving only the center area active for focusing - so you can't really use all the cool AF enhancements Like Face Detection, Eye Focus, and other stuff that Sony has built into its firmware. Holding a camera with CIZ enabled is harder as the focal length increases, since the stabilization system doesn't seem to take digital zoom into consideration. Besides, as you noted, you have to be pretty happy with the results from the camera with CIZ - since it doesn't work with raw files.

Lens quality has a lot to do with what the results as well - if you take a lens that is acceptable or mediocre, it will only get worse when you apply digital zoom - CIZ or Smart TC.

There are no cheap shortcuts to longer lenses unless one is willing to accept considerable compromise in performance and image quality.

MDI Mainer

Surrebuttal:

Although we are not with the A65 talking about CIZ, other respected members here and elsewhere do not share your opinion of using CIZ vs. post processing. Nor is everyone's experience level with Photoshop, et al. the same. And while I fully agree that there is no substitute for a good, long lens, it is not reasonable to expect every member to want or need to invest in that gear, especially for a camera body introduced in 2011.

From Gary Friedman:

At this point it makes sense to do a test: How does ClearImage Zoom’s upsampling feature compare to taking the same image with ClearImage Zoom OFF, then cropping and upsizing in Photoshop? I performed the test on the sample in Figure 7-12 and the result can be seen in Figure 7-14. Sony’s marketing department wasn’t overselling; it’s very hard to tell the difference.

Gary L. Friedman. The Complete Guide to Sony's Alpha 6000 Digital Camera (Kindle Locations 6668-6671). The Friedman Archives Press. Kindle Edition.

His conclusion about digital zoom in the real world -- a purist won't like it, but sometimes it's convenient and/or the only viable option.

billnikon Loc: Pennsylvania/Ohio/Florida/Maui/Oregon/Vermont

I would suggest you call Tamron to see if they recommend a 2X for that lens on the A6500 camera. Many large range and slow zoom lens manufactures do not recommend it.
You may also cross the threshold for auto focus on that particular camera. If it is maximum of f8 0n that camera, you may be in trouble. That lens goes to f6.3 at 270mm, with the 2x your now your talking somewhere between f11 and f16, I do not believe your camera will auto focus at that f stop. And besides, you are talking a focusing speed of a 119 year old and your focusing brightness in the viewfinder will suffer greatly.
I personally do not believe this is a good move especially if your looking for decent images. Just my honest opinion.
Good luck and keep on shooting until the end.

imagemeister Loc: mid east Florida

Since the 18-270 is an older large ratio zoom, the native IQ @ 270 is marginal at best by most people's standards and therefore a poor candidate for using a 2X extender and the attending degradation. IMO, your best compromise is to optimize the native IQ of your lens and CROP and use pixel enlargement software to restore perceived resolution for larger printmaking. AFAIK, the A65 does have CIZ - if so USE it !
.

47greyfox Loc: on the edge of the Colorado front range

Buy an extender for this lens? Listen to Gene51 and others (and me), you’ll be throwing good money after bad. You’ll use the extender once and wonder why you bought it.

the hiker Loc: San Diego

Thank you for the info.

User ID

Right. CIZ is just plain useful. But *useful* doesn’t sell well among the UHH “online experts”.

Things I’ve done over the years for clients would be considered horror show scripts around here ... processing film in Dektol, using the “wrong half” of a 4x5 Symmar as a normal lens for 8x10, working at (OMFG!) f:32, using “not recommended” TCs ... anything taboo around here, I’ve prolly been paid for doing it.

MDI Mainer

Years ago I had a mentor who always cautioned his associates not to let the perfect be the enemy of the good, and that's advice well taken in many aspects of life, including photography! But the expression dates back at least to Voltaire.