M50ii + EF-S 55-250mm STM + Kenko SHQ 1.5x Teleconverter

Larry Rexley wrote:

JasonS70 wrote:

Thank you Larry, Thrilla and Alan for your feedback and suggestions and my apologies for taking so long to reply, work and life have been hectic

So taking everything said into consideration I have been out again for some more practice. I shot in manual so I had better control over the shutter speeds, and set aperture to 5.6 a couple of times. Had ISO set to auto with max now 1600, previously had it set to 800. I admit I am still confused about the effects the teleconverter has on the aperture but 5.6 or 5.0 seems to be working ok. Of course the better the light the better things work

The following are some recent shots while hiking my local track. If I get everything right the results are fine, any photos that don't work out are because I have not paid attention to what I am doing

Again many thanks for the advice, I am happy to keep using the teleconverter. I have even slipped in a 10 pic pano I put together using this combo. All photos are the full size end result, even with the extra reach I find myself cropping in a it. The pano of course has been resized, the original is quite large

Cheers

Jason

Great results. Those now look very close to my 'out of camera' results with the EF-S 55-250 IS STM + Kenko 1.5x SHQ teleconverter.

They are not quite as sharp and clean as the lens without the teleconverter, and again I think it's because your software is correcting for the lens only and not the lens + teleconverter combo which is a different set of optics needing different corrections (more chromatic aberration adjustment, and a different sharpness algorithm.).

In my case I use DxO PhotoLab and add more CA correction, and use some unsharp masking (Threshold 0, radius 91, Intensity between 50 and 100) to touch up that sharpness to look close to the lens only images. Also DxO Deep Prime's algorithms and debayering naturally help with clarity and detail on nearly every image anyway.

Congratulations on your new lightweight, image-stabilized, super-telephoto lens.

Most of the time I use my EF-S 55-250 IS STM with the Kenko 1.5x teleconverter as I already have the EF-M 18-150mm zoom covering the lower end of the 55-250 range - a 80-375mm lens complements the 18-150 better since I often shoot with two bodies and need the extra range.

The f-ratio is the effective focal length divided by the physical aperture of the lens. When you put the teleconverter on the lens, you are multiplying the focal length of the lens by 1.5x. but the teleconverter does not change the diameter of the physical glass opening on the front of the lens. So the effective f-ratio is now 1.5x what it was before --- so setting f5.6 in the camera becomes roughly f8.

Modern teleconverters have a chip in the electronics that is supposed to magically 'change' the f-stop passed from the lens to the camera --- converting f5.6 to f8, for example, but a 'dumb' teleconverter without a chip, or with the chip removed, doesn't do this, so the EXIF data in the image needs to be 'converted' to one stop darker.

Thanks for this info Larry. I got the chance to try out the conversion you sent me a few weeks ago, but haven't had the time to post process anything yet. I'll have to invest in some new software!