checking for sharpness

i want too check for sharpness , on playback screen on camera if i zoom in all the way to the focus area should the zoomed part of the image on screen be sharp? i dont have a tripod yet but im making sure the focus point square doesnt move from the point im focused on after the shot is taken and shooting at 500 shutter speed at 55mm

here are my user settings using a 4.5 55-300, any advice here

u1
easy iso , love that i can adjust just using wheel , set at 100
aperture priority
focus afs s and s on the right hand side 51 focal points .13
raw
i would change too afs c for moving shots is that correct , im using afs s for portrait and landscape

u2
easy iso 100
aperture priority
focus afs s s on right 51 focal points .13
jpeg L fine
auto wb

I don't think you can really just look at a zoomed-in portion of Liveiew and truly judge the sharpness of a lens.

U1 and U2 settings are not relevant to lens sharpness at all.

i realise the u1 and u2 dont effect sharpness it was two questions in the one post lol sorry , just after suggestions on user settings

its just ive read before that people zoom in too check sharpness and i was worried as mine are sharp up until the last one or two zooms
i guess then i could ask the same question for photoshop what is the zoom percentage too check sharpness, is it zoom in photoshop say too 100%?

and the same question for live zoom to set sharpness on manual focus for night shooting , can you zoom all the way in focus to tack sharp if possible , i dont have a tripod so i cant do this yet

Not sure if you know...Your shutter speed should be faster then the length of the lens...Re 300mm Shutter about 1/450 sec...

I use AF-C when not using a tripod...If I or the subject moves the camera will re focus...

Like a couple of answer here already pointed out, you really can't tell for sure by looking into the view finder or the LCD if you got it really sharp but you can get very very close. The only absolutely sure way is to download the image into a large screen (minimal 13" laptop) to see if you got it tack-sharp. That's why those of us shooting models in studio shoot tethered. But having said that, the autofocus really does a good job if you use the right mode for your particular situation. Also, make sure the you have adjusted the diopter settings in your viewfinder properly - otherwise all bets are off. Look into the view finder and look at the info displayed at the bottom - adjust the diopter setting until you get displayed info very sharp for your eyes - especially if you wear glass, or worse like me with bifocals.

Now if you are really obsessed about sharpness, you can use manual focus - but unfortunately cameras like these are not designed for manual focus - it's a pain - no split screen and lens focus ring is small and with very small angle of turn from end to end making it too sensitive to fine focus.

Here's someone who makes a split screen focus screen for the D7100:
Nikon D7100 Focusing Screen

I'm so tempted to buy one - when I have the balls to take my camera apart to install it - I will!

i wasnt really thinking about the crop sensor as far as focal length v shutter speed , i was working off 300mm 300 shutter , with vr lenses wouldnt you be able too shoot 300 mm with 300 shutter

how far do you zoom out say in photoshop with a 15.6 inch laptop too check sharpness , is it 100 percent?

egosbar said:

i wasnt really thinking about the crop sensor as far as focal length v shutter speed , i was working off 300mm 300 shutter , with vr lenses wouldnt you be able too shoot 300 mm with 300 shutter

Click to expand...

You can shoot any shutter speed you like with any focal length. Whether you can hold the camera still enough to prevent blurring is another issue.

egosbar said:

how far do you zoom out say in photoshop with a 15.6 inch laptop too check sharpness , is it 100 percent?

Click to expand...

Monitor size is not relevant..... just go to 100%.

Put your camera on a tripod stop down the lens use a cable release then check the file at 100% see what you get !!

yeah ill be buying one when i go on my cruise an a couple of weeks and a cable release , do you think these the eyelashes are sharp or how much sharper can i get

yeah ill be buying one when i go on my cruise an a couple of weeks and a cable release , do you think these the eyelashes are sharp or how much sharper can i get , i focesed on the eyelashes of the front eye