chats005 wrote:
When do I need to calibrate my lens when I do post editing in Lightroom?
Also, I need a recommendation on the initial steps to take to edit an image.
Lastly, how do I crop an image and ensure it will still be 16MB for a printed enlargement?
Thanks, I appreciate the insight and recommendations in advance of receiving any responses.
1) Lens "calibration" and post processing have no connection. You can, however, create a custom camera profile, or use one of the canned ones. I use an XRite ColorChecker Passport to create custom camera profiles.
2) Everyone's workflow is different. If you are working with raw images, there is no "sequence" of steps to take. But the biggest first step is to take a critical look at the image and give some serious thought to what is missing or what might be improved by using the sliders and tools in Lr. Nothing is permanent, in that if you take your editing down a path you are unhappy with you can reset the specific section in the Develop module or reset the entire image. Or create a virtual copy and reset that, etc etc etc. The original image is never changed, only the preview and the xmp file (if you are using that) will be changed - and not irrevocably.
3) What is your rationale for needing a 16 mb image? It is more important to have enough pixels in your image to print, not a specific file size.
This will tell you all you need to know about the relationship between print resolution, print size, viewing distance and the limits of human vision.
http://www.photokaboom.com/photography/learn/printing/resolution/1_which_resolution_print_size_viewing_distance.htmLastly, if you feel that your autofocus is not working with the accuracy you expect, you can test it by putting the camera on a solid tripod, and using the maximum aperture, take two series of pictures - one using the viewfinder, and the other using live view. If the live view image is consistently sharper, this indicates that the lens-camera combination is not optimal and is in need of adjustment. If this lens behaves similarly on other camera bodies - the lens itself needs to be adjusted. If all of your other lenses on this body are fine but one lens is misbehaving, the lens is at fault. If none of your lenses are as sharp the viewfinder AF and are fine with live view - then the body needs servicing.
Focus errors are rarely the same at all distances and focal lengths (if using a zoom). While many cameras have some sort of AF fine tuning, relying on the single point of adjustment almost ensures that in an effort to make a lens not front or back focus when zoomed to 150mm and shooting a subject that is 50 yds away you will affect how is focuses at 10 yds and zoomed to 100mm. If it was fine at 100mm and 10 yds before the adjustment, it won't be after the adjustment. Technicians have access to tools we don't have, and they can use multiple points of focus and distance to adjust a lens, and they can do it in the camera or on the lens or both. So, my advice is to spend only enough time to determine if you have a problem then hand it over to the manufacturer's repair techs to resolve it. You'll be happy you did.