Hi Everyone;
Like many of the people writing in, I've sprung for a couple new lenses. About a year ago, I did the same and basically I just shoved the lens on and started firing away. I'm betting there are more than a few of us that have done it. But, it got me thinking. Is that the best way to do it? Depending on who you buy from there can be no return or some sort of 14 to 'X' day return policy in effect on the purchase. After that it is through the warranty. So, identifying problems early is important.
I'm wondering if there is anything systematic that people are doing to inspect their new lenses? I see many posts where people are asking if they have a bad copy or they have already identified that they have a bad copy and exchanged it for a second. It dawned on me that unless it had a giant crack in the glass I wouldn't really have a clue what I'm doing. Of course, if the lens couldn't even focus on my couch in broad daylight then I would worry.
So... What is it that you do when you inspect a lens? I've been doing a little looking around and can find some suggestions, but I do think a really nice checklist would be good to have for those aiming to move beyond their kit lenses. Many of us are ordering on-line. I don't have a bricks and mortar show within 4 hours drive from me so inspecting before hand isn't possible.
I'm thinking something like:
(1) Look for any obvious sign of physical use (did they sell it as open box?). e.g. are there scratches on the rear mount. Any sign of damage to the glass when you open it. Do all the parts and rings appear to be solid? No early signs of nicks and cracks. If any of this then contact the seller. Should it have been priced differently? or be returned?
(2) I'm curious whether anyone cleans the mounts before they attach the lens to the camera? I didn't and I'm wondering based on my internet wanderings whether I should have. (As an aside, when or how often should they be cleaned?)
(3) Get a good look at the lens in light... Questions: How much dust is too much dust in a new lens? Should there ever be dust in a new lens? Some people talk about oily blades on both used and new lenses. Ummmm... I'll be honest, I don't know what an oily blade looks like so... Pictures anyone? How much is too much? Also, I can see stuff about looking for pieces of plastic in your lens. I'm assuming that means loose in your lens floating around... I vote for that probably not being a good thing...
(4) Ok, now so far we have done the appearances. So, I think we can shove it on our camera now. I'm wondering if there are a few really basic easy test scenarios that we should all try with our new lens to very quickly know if we have to move it up a notch? I can see that people have already written about how to test front and back focus:
https://www.pentaxforums.com/forums/pentax-dslr-camera-articles/167547-how-fi...ack-focus.html
But that seems excessive to me when I've just pulled my new lens out of the box. I really only want to get to the fine tuning if I'm pretty sure I need it. So any simple recommendations of quick and dirty tests we should do with a new lens? If there are, please let me (us) know what we are looking for and what we should do about it. e.g. if you shoot this and it seems a bit soft then do the front-and-back focus. If this, then the lens needs to be returned in the 14 days or is this something that we should do via warranty?
Finally, many people are using Pentax lenses and there have been concerns on occasion about their SDM. Is there any early warning signs that there is something wrong that people should be listening for?
Or is this all really unnecessary? And, like last time, should I just shove the suckers on and start firing?
Many thanks!
Eric