Originally posted by zxaar My view is that just because someone does not know the difference , it is not good idea to sell him something worse at the price of something good.
We don't know that it is worse. When you make a cheap lens, you have to make trade-offs, and the hope is that making it relatively slow has enabled them to improve the image quality. If so, then that could be a good trade-off for the intended market.
Wide apertures are mainly for two things: shallow depth of field and low light. For newcomers, the wafer thin depth of field of f/1.4 can be a liability because it is so hard to work with. They have enough trouble understanding focussing as it is. They are used to tiny sensors with huge depth of field that covers up focussing problems. Shallow depth of field is one of the few things that still makes SLRs harder to use than compacts.
As for low light, with the K-x and K-r Pentax have the advantages of (a) best high ISO performance of their class; (b) image stabilisation in the camera. You can ramp up the ISO and use slower shutter speeds and still get good results. This makes it less important to get low-light performance from the lens. Other manufacturers need f/1.4 more than Pentax do.
I'm not saying it's not a compromise. I want the moon on a stick, same as everyone else. I'm saying the trade-offs for Pentax are different to those of rivals. With this lens they are playing to their camera's strengths.
Quote: He is nice guy and today i am thankful that he did not believe that since general user will not notice difference it is alright to sell him anything.
That cuts both ways. If it turns out that the Pentax f/2.4 delivers better results than a rival f/1.4, a good, knowledgeable salesman will guide customers towards it. In that regard, it doesn't matter so much if the customer is ignorant and doesn't do research.