Autofocus Compensation: In search of "Tack Sharp" I jumped on a device to, I thought, give auto focus compensation a try. Of course, I jumped before understanding anything about this...

gtobey Loc: Beaverton, Oregon

In search of "Tack Sharp" I jumped on a device to, I thought, give auto focus compensation a try. Of course, I jumped before understanding anything about this process. Found nothing in my D90 manual - even went so far as to download a D7100 manual. So is it only certain cameras or is the adjustment in the lens or... The device I purchased is from Focus Pyramid.

MT Shooter Loc: Montana

gtobey wrote:

In search of "Tack Sharp" I jumped on a device to, I thought, give auto focus compensation a try. Of course, I jumped before understanding anything about this process. Found nothing in my D90 manual - even went so far as to download a D7100 manual. So is it only certain cameras or is the adjustment in the lens or... The device I purchased is from Focus Pyramid.

I believe you are asking about "AF Fine Tuning"?

OonlyBonly

This is the product mentioned in the question.
http://focuspyramid.com/autofocus-lens-calibration-tool-canon-nikon-sony-olympus-and-pentax-af/

Boobarf Loc: Kyle, TX

gtobey wrote:

In search of "Tack Sharp" I jumped on a device to, I thought, give auto focus compensation a try. Of course, I jumped before understanding anything about this process. Found nothing in my D90 manual - even went so far as to download a D7100 manual. So is it only certain cameras or is the adjustment in the lens or... The device I purchased is from Focus Pyramid.

I recently purchased the Pro version fro FoCal. This is lens Auto Fine Tune software and I found it to be "helpful" but not perfect. It seemed yo be less than accurate on my Zooms (24-70 2.8 & 70-200 2.8 Nikons). I am using the software on my Nikon d7000 and it is installed on an iMac.

CO

The D90 doesn't have the auto focus fine tuning feature. The D7000 and models above it have the feature. Sometimes you'll have a camera/lens combination that will back focus or front focus a little. I have a D90 and fortunately the auto focus seems to have been calibrated well at the factory. I use the DataColor SpyderLensCal to fine tune my lenses on my D7000. It works well. I don't have experience with the FoCal software but I've read that it is good. You shouldn't have to apply much compensation. A few units in either direction should normally be enough.

dpullum Loc: Tampa Florida

OK, POF well taken... appears to be a 45-45-90 triangle 4" 4" 6" (closer sq rt of 32=5.66) face. The whole thing is tilted back with the 5.66" as the table contact base. e.g. back at a 45* angle. The calibration on the face is probably in mm with the horizontal at mid point. Good Idea well designed and printed.

However, I believe that two 6" rulers calibrated with mm and a henge and quick check 45* would fold into your case easily and almost indestructible. The nice looking, good idea, cardboard unit is a bit fragile for $25!

planepics Loc: St. Louis burbs, but originally Chicago burbs

I thought I had a focus problem with my Tamron lens and thought it was front-focusing and was going to adjust it with the fine tune feature on my A77. As I was talking to Sony about it, I discovered that I must have been closer than MFD. Made a huge difference and seemed like everything was AOK, but I'm still not 100% happy with my 300 mm shots...can't afford a $2k lens, though. I used 5 AA-sized batteries at a (somewhere close to) 45 degree angle for my test. My 18-55 still seems a bit more accurate.

rpavich Loc: West Virginia

dpullum wrote:

OK, POF well taken... appears to be a 45-45-90 tri... (show quote)

This is true, not that the cardboard thing won't work, but it's expensive for what you get.

You can take a ruler, put something under it to prop it at approx a 45 deg angle (angle not important) and then set something at the 6" point that's straight up...like a box, or a can...anything with a face that's flat and vertical.

focus on the vertical face, then check out how far forward or back your focus really is based on what numbers are blurry on the ruler.

I've made these out of a cardboard box and ruler...

Here is one I made out of an office file holder and a steel ruler.

http://www.uglyhedgehog.com/t-36223-1.html

mwsilvers Loc: Central New Jersey

gtobey wrote:

In search of "Tack Sharp" I jumped on a device to, I thought, give auto focus compensation a try. Of course, I jumped before understanding anything about this process. Found nothing in my D90 manual - even went so far as to download a D7100 manual. So is it only certain cameras or is the adjustment in the lens or... The device I purchased is from Focus Pyramid.

Micro focus adjustment is a feature of the camera body not the lens. Not all bodies have it. The D90 appears to be one that doesn't. For those without MFA, Sigma's new range of lenses can be adjusted off the body with the use of their USB dock. It only works in the latest Sigma lenses but can change focus at 4 focal lengths and four distances for each focal length.