As I was recommended in the question How to determine which lenses are good at testing teleconverter quality? I was taking test pictures trying to determine lens/teleconverter quality. No I did not have a proper test chart available but figured the bar-code on a box I had laying around would get me partway there.
Attaching 2 1-1 crops from my tests, I am correcting colorcast and color fringing when doing raw conversion in Digikam. The first image is the bare lens the second is using the Kenko Pro300 3X Teleconverter.
Test shots taken with a Canon 5D Mark II and an adapter SMC Pentax-M 135mm f3.5.
- Focus: Manual
- Mode: Aperture Priority
- Remote Trigger: Yes
- Tripod: Yes
- Mirror lockup: No (will use this when re-shooting)
As can be seen neither image is sharp when pixel-peeping at this level but if anything the second image (with tele-converter) is even less sharp, unsurprisingly.
What are the optical problems in these images, can they be identified from the attached files? Is it just me missing focus? Is it the anti-aliasing fitted in the camera? Is it the quality of the lens (would a better lens be sharper with the rest of the setup the same)?
More test images based on comments
Two more test images with updated settings based on comments, the first one is without TC and the second one is with, cropped from in camera JPG.
- Focus: Manual
- Mode: Aperture Priority
- Remote Trigger: Yes
- Tripod: Yes
- Mirror lockup: Yes
- Picture Style: Standard (sharpness 4)
- White-balance: Tungsten
- Aperture: F8
- Exposure: 20 seconds with TC, 3.2 seconds without
- ISO: 100
In the process of shooting these the most surprising improvement was mirror lockup, there is still some fussiness but the tips applied have it much reduced for both configurations.