Hi all. I thought this would be a good place for some wise advice regarding a lens purchase.
A year ago I sold my Canon 5DMKII and lenses and went all Nex-7. So far I have been very happy. I shoot 99% landscape from a tripod. I currently own the two sigmas (19 & 30), and a Contax Planar 50/1.7 mounted on a Metabones Speed Booster.
My most used lens is the Sigma 19 (28 mm is my fav. focal length), the lens is OK, but I have been struggling to get sharp images with this lens. One of my main issues with the lens is the lack of focus-scale. I do a lot of long exposures and night photography, and not having a scale on the lens barrel can be a real challenge.
I would like to purchase a 28mm (35mm equivalent) lens for landscape work. Sharpness is one of my main concerns. I value detailed prints, and they are simply not happening with the Sigma (the "Sigmarit" 30 is a fantastic lens though). My typical print would be 15-20 inch. I shoot black and white exclusively.
I have considered getting the Contax Distagon 28/2.8. The lens seems to have a fantastic reputation as a landscape lens, and mounted on the Speed Booster it would give me the desired FOV. I am just very worried that using a lens mounted in the SB might not be a very good idea for infinite-landscapes.
I would like to hear your opinions regarding this issue, I would value your recomendations. I have a ton of cash invested in filters, all in 77mm thread, so the filter size is a serious factor. I have considered the Zeiss 18, but the filter size and the price tag are a problem. I have a budget of roughly 500$. Anything more expensive would mean selling the SB and the Planar (Which I hardly use anyway) but staying within the 500$ budget would be a plus.
Thanks in advance for all your help and opinions.