I did this test as a poll to investigate what is the meaning of the MTF numbers out of the test charts.

It's a user test - made carefully, and with a level of accuracy as good as a simple/ordinary (i.e. non-scientific) setup and technique allow.

The methodology:

I shot seven photos with the same exposure value, with a brand new Pentax K200D camera and also a brand new Pentax SMC DA 35 mm Macro Limited lens both acquired from legitimate, authorized and well reputed suppliers. The equipment seems not to be defective,  so I can't list any problem with it. Same to the lighting set-up, tripod, cable release and whatever.

This lens is rated as An optical Paragon by Mike Johnston and Carl Weese (I need to say, I agree), but some people (a lot of?) disagree.

Apertures: f/2.8, f/4, f/5.6, f/8, f/11, f/16, f/22

The target was illuminated uniformly (checked with a lightmeter) and the focus was locked - the sensor alignment was virtually parallel to the target.

Camera on a tripod, 2s mirror lock and remotely triggered.

Capture mode: RAW format = DNG.

Workflow:

Step 1

I opened all images in the ACR 4.4 and choose an aleatory image to start with the first adjustments:
White balance adjusted with the WB tool pointed to the gray card
Basic adjustments (based firstly in histogram and secondly on visual evaluation ): All parameters as follows:

All other values = 0 (zero)

If you want, you can download the xml preset on the results page.

All seven images syncronyzed as mentioned.

Step 2

Vignetting correcting as follows:

Step 3

Exposure adjustments to match the default as follows:

Step 4

All files saved as 16 bit uncompressed TIFF.

Step 5

All images opened in Photoshop CS3. I realised that the photo taken with f/2.8 was a little darker, so did the following leves adjustment:

All the other images remain unedited.

Step 6

Smart Sharpen = same setting value for all images as follows: 

No one other edit was made.

The six files from f/2.8 to f/16 were scrambled, tiled vertically and Print Screens of six  selected 100% crop areas was captured and saved as 95 JPGs quality.

According the Lens Reviewer Website Photozone.de the MTF numbers for this lens, tested in a K10D (same sensor of the K200D) is:

These numbers generate a lot of discussions about the image quality in the web forums, (I specially read most of the messages of the  DPReview's Pentax SLR Talk, of the  Photo.net Pentax Forum and of the Pentaxforums)

After all the discussions the question remain:

- Whats the real importance of the MTF numbers by a photographer point of view?

My brief conclusion: f/22 is pretty bad for this lens and the MTF number confirm that - I threw away it for the test.

Ok, and about the other numbers? For that particular scene, it might be surprising.

Take your own conclusion...    >>>  Start the test - 2nd round

Hint: After the test has been done, you will be able to see the results of the 1st  round.