theehmann

I have a Nikon D 7200 and am asking if a 1x tele extender would work on my Tamron 100-400. If so will it be relatively sharp?
Thanks in advance for your response.

CHG_CANON Loc: the Windy City

The Tamron 100-400mm f/4.5-6.3 Di VC USD Lens is a variable aperture lens, where the max aperture gets smaller as the zoom extends. Losing 1-stop via a 1.4x extender makes this lens a darker f/7.1 to f/9 lens. Your D7100 will struggle for auto-focus at the longer focal lengths when the effective aperture is smaller than f/8. You might be able to manual focus or use LiveView. Your intended uses for this extended focal length will determine if this configuration is useful / possible for your intended purposes.

With an extender, the image sharpness won't get better. At best, they will remain virtually the same. Are you getting any 'pin sharp' images at 400mm with the lens? Are you shooting moving subjects at 400mm or just static subjects from a tripod with LiveView and careful 10x zoomed focusing?

theehmann

Thank you fir your reply. My main reason for exploring this extender is to photograph birds.

SeaBrat Loc: St Petersburg, FL

I agree with CHG_CANON. The Tamron-USA web site shows the 1.4x is compatible with the D7100 and 100-400mm for AF at f8. I have one for sale if you are interested.

theehmann

Thank you. I may be in touch.

ClarkJohnson Loc: Fort Myers, FL and Cohasset, MA

I have the same lens and have been tempted to try the 1.4x extender with my D500. Yes, it would function. But logically, the loss of light on this F/6.3 lens would substantially impact the ability to focus, and the IQ would suffer, so IMHO getting one would be an expensive trial with uncertain results. Is anyone in the group that owns this combination actually enthused about the results using the Tamron TC?

theehmann

Thanks for your response.

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

1X tele entender's work best on a PRIME lens.
They work least well on a slow zoom lens.
You can take that advice to the bank.

olemikey Loc: 6 mile creek, Spacecoast Florida

Cheapie suggestion - Did you try changing the Image Area setting on the D7200, that will give you another 1.3X, with no cost, NO LIGHT LOSS, and a frame full of shot at 15.3MP. I can't tell you if changing "Image Area" is better or worse than a TC with your particular lens, but it takes away no light, costs nothing, yields an approx. FOV of a 520MM at full zoom with a 100-400. I prefer that to adding a TC to my D7200 or 7100, and you can tag/reassign a button for immediate change form DX to 1.3X and back. My TC's sit on the shelf, don't use them anymore..... and if you do not like it, I didn't spend any of your money, you can still go spend it!!! Just my opinion - YMMV

Pistnbroke Loc: UK

Changing the crop to 1.3 will make no difference to the size of the bird image on the sensor .Just as many POI. You may as well just crop after you take the shot and you got more change of keeping a moving bird in the frame at full size. Using a TC is always worse for IQ than cropping.
PS I have two of these lenses

olemikey Loc: 6 mile creek, Spacecoast Florida

Geez, That it is an internal crop is not the point - I'm just trying to save the OP from spending good money and not finding happiness (one offers up a no cost/no effort method to try out, and someone always craps on it - why ?) based on real life experience. Yes it is internal crop (I thought/think we who have the knowledge all know that already). The field of view changes. Yes you can also crop either way, but you can make the subject larger in your initial photo without spending a dollar, and you can still crop the 1.3X image if you need to.

I have 6 TC's, from way back in film days to current, but no longer use any of them. I do use the 1.3X on my Nikon "when I want to", and when shooting JPEG with My Sony DSLRs I use the Clear Image Zoom (also a digital internal crop) since it goes all the way to 2X. I get excellent photos and fine feather detail, etc., but I do practice excellent technique, it wouldn't help a sloppy shooter.

If you use good technique the 15.3MP will still yield a fine photo, unless you are heavy into pixel peeping or print huge, but with good technique it won't matter. I use it a lot in the field, esp. if I need a little extra reach to fill the frame and I'm not carrying extra glass, which is what "I like". If you don't like the 1.3X switch, that's fine, but let the OP check it out.... it's a freebie for gosh sake, no harm, no foul.

imagemeister Loc: mid east Florida

The Tammy 100-400 is a very good lens. Using a 1.4X, IMO, in GOOD light, the results would be "acceptable" - assuming AF speed and accuracy was a relatively low priority.

In lower light, or where AF performance is a high priority, I would just optimize/maximize the native IQ of the lens and CROP and use well applied pixel enlargement software if necessary.
.

SteveR Loc: Michigan

Remember, f7.1 would be with the focal length at 100mm. f9 would be at f400, which would be beyond the capability of the camera to autofocus. Even if it did, it would hunt and hunt and never really AF as needed. I have an idea that your are thinking about birds in flight. I have a friend in Utah, who used to post on UHH as Judy 2011, who gets tremendous bird photos using a Canon 100-400mm L lens on a crop sensor camera, but photographs them in situ.