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I was asked to provide some 100% crops of some images taken with the DA*300. I set up the boxes shown below on a table in our garden for the purpose of the experiment. I am not used to doing this kind of thing so please feel free to comment on the procedure as well as anything else. I wanted to take images using the lens on its own as well as with the Kenko Teleplus 1.5x DG TC and Kenko Teleplus 2x MC7 DG TC. In practice I have concentrated on the upper TC box on the left for the crops. I took shots at every aperture with and without the TCs. I have only included the ones with the lens at F4 and F8 here. If you want me to post any others please let me know. As with most lenses I think IQ improves with the lens stopped down a bit. For the shots with the TCs I moved the table further away as it seemed a good idea to have the image roughly fill the same area of the frame. The camera was on a tripod and I used a cable release to fire the shutter. I realised after doing all this though just how much a camera can shake even using this method. I was surprised how much the camera juddered each time the shutter fired. In hindsight I have realised the carpeted surface that it was on was not ideal. It would have been better on a more solid surface. Also perhaps I should have further dampened any movement by placing my hand on the lens? The other thing I should mention is that all these were taken at 800 ISO. I meant to adjust to a lower ISO setting but forgot. Also camera settings were at Sharpness +2 and Contrast +1. I have had the camera permanently on these settings following advice in a Review when I first bought it. Anyhow, hopefully all these factors are not that significant.
Just to clarify that the Kenko Teleplus 1.5x is the SHQ version with the power zoom contacts. The 2x has similar contacts. The boxes that Kenko supply for their TCs are confusing as they do not give precise information as to the model.
Overview:1/2000th, F8
When I was first asked to do 100% crops I wasn't sure what this meant. I think I have found out the meaning but I had better explain the procedure that I followed just in case I've got it wrong. I used Corel Paint Shop Pro Photo XI to view each image at 100% and then did a crop of the image. If this isn't the right procedure please let me know.
Lens on its own, 1/4000th, F4
Lens on its own, 1/2000th, F8
Lens with 1.5x TC, 1/2000th, Lens at F4
Lens with 1.5x TC, 1/750th, Lens at F8
Lens with 2x TC, 1/1000th, Lens at F4
Lens with 2x TC, 1/350th, Lens at F8
For those of you who prefer a live subject this is a 100% crop of the squirrel image I posted a few days back. This one was hand held.
Lens on its own, 1/180th, F8, Exp Comp -1.0
Paul
Last edited by channeler; 09-25-2011 at 05:41 AM.
Reason: Clarify Versions of Kenko Teleplus TCs