Originally posted by jaikumarr18 Thanks guyz. That is a lot of information. To be honest, until now I didn't know about the interchangeable screens.I actually thought 18-135mm WR lens would be an all-round lens but had issues during dim light condition and with sharpness on the portraits. And now looks like manual focus is a whole different thing.
So am not sure if I need to go for a different lens if interchangeable screen was not one of my option.
One thing you may want to check is whether your lens is front or back focusing. Under bright light, the lens may stop down, and the increased DOF may mask this problem. Under dim light, with the lens more wide open, the lower DOF may reveal a problem that is there all the time. You may just need to fine tune the autofocus on the camera for that lens. If it turns out that it's not a front/back focus problem...
I don't own that particular lens, but no lens is going to cover every base. There's always a tradeoff. That lens has a fairly wide zoom range and is relatively inexpensive, so the tradeoff is that it doesn't have a
wide minimum aperture. It's not a fault of the lens - this is the nature of the physical world we live in and the trade-offs that have to be made.
A wider minimum aperture will give you a brighter view through the viewfinder, which may help with manual focusing.
But you'll either have to pay more for the lens, or give up some of that zoom range. And it might end up being bigger ( depending on whether or not you've given up zoom range ) Those are the trade-offs.
I've considered replacing my focus screen as well. Another less intrusive option that I've seen recommended in the forum is a viewfinder magnifier that you attach externally. I'm debating trying that option as well.
Using focus peaking in live view really is a nice option if you can make it work. I'm usually shooting outdoors in bright light, so it doesn't work for me because I can't really see the screen most of the time.
One of those hoods that goes over the LCD screen isn't really practical for me either, unfortunately.