Iain

For some time I have had a 70-200 2.8 paired with a D500 which, for the majority of photos is fine; the majority of my photography is of kayaking events which provide fast moving subjects and variable distances.  However, reach is sometimes an issue and heavy cropping can be required.  To try get over this, I have a 1.7 converter to further boost my 70-200 to 510mm with the crop factor.  Not satisfied, I have recently tried the 200-500 5.6 but I have to say that I really am on the fence if the £1,000 spent on this lens is worth while.  Results have been ok but the sharpness does not seem to be the same as with the 70-200 and some more distant photos e.g. 80mtrs have been disappointing.  Perhaps, as an amateur, I am expecting too much and should not expect the quality I see in similar photos taken by others on full-frame cameras and prime lenses.

Grateful for any views about this dilemma.

I have recently moved from Apple back to Windows and installed my off-line version of Lightroom 6 in the Windows form.  However, it seems that files from my D500 are not recognised and I have now also installed Adobe DNG Converter which seems to work.  However, I have noticed that the DNG files are a bit smaller e.g. about 19k KB vs 23k KB in NEF format.  Does anyone know if this will result in a loss of data/quality?  I am only an amateur and do not focus on every pixel in detail but do want to know that my better photos can be enlarge if wanted e.g. up to about A1 size.  Any comments would be appreciated.