Hi, this may be true, but given that the tests focussing manually using the green hex were quite a way out both sides of the 1.2 mtr mark I don't think this is the main issue. Using the hex I had differences of up to 100 mm either side of the 1.2 mtr mark. This demonstrates my inability to focus accurately using the green hex. I need a split screen or an AF lens. This getting old is becoming a problem.

Many thanks, Richard.

Hi Everyone,
Just done another newspaper test using Bob's idea.
Tools: 1 Manual Pentax prime, 1 Chinon manual prime, 1 18-55 mkII autofocus, all used manually.
Test: Tape newspaper to wall, set camera on sturdy tripod, set front element 1.2 metres from said newspaper. Also as final test set autofocus to autofocussing to compare.
Results : When lens set on barrel to 1.2 metres the results were excellent. When barrel spun and returned slowly until green hexagon lights, the results were basically so, so poor. When this was checked against the barrel distance markings it was found to be quite inaccurate. Either way the barrel was turned the inaccuracy was either more or less than the 1.2 metres. This seems to indicate that on the prime lens the focussing hex in the viewfinder is not accurate manually,yet is accurate when used manually on auto lens.
Many thanks for all your help, I am now going to take up painting.
Regards, Richard.

I have done comparisons at all apertures with 2 manual + 2 autofocus lens manually. Only the manual primes give me problems. Both primes are bayonet mount. I have used o right angle magnifier on the view finder, I have checked the diopter setting. I am now going to set the lens/newspaper distance according to the barrel markings and try Bob's idea.

I do get some sharp images, but it only seems to be in any one session. I mean 1st session okay, change for another lens, replace for 2nd session and the results awful..Soft is not the word, we are talking well out of focus. If I set up the lens to f22 and focus on an object 25 feet away, everything between 8 feet to infinity shoulc be in focus (according to the barrel markings). Not so, nothing in focus, but using the kit lens okay. Surely both my primes cannot be faulty for 60% of the time.

Hi, I have bought a 50 mm f1.7 Pentax manual prime for the shallow depth of field. I am problems focussing with any consistency, in fact I get better results through the bottom of a milk bottle. I have the same problem with another manual prime (Chinon 50 mm ). I have done all the tests, Newspaper on wall, on and off tripod, all apertures, everything. At f22 the results are awful. During these tests I have also used the 18-55 kit lens manually and the results are excellent, which shows I can focus. I am using a Pentax K10D which is superb with all the autofocus lenses I have tried, manually or otherwise. If anybody can help tell me where I am going wrong I would be extremely grateful. By the way, in my 30 years of pre-digital I only ever had manual lens.