[madison_wi_gal]

My previous post got a bit sidetracked since I only had an APS-C to test my new (refurb) 28-105. I now have a K1-II for 6 days from Lensrentals.

So: I have a brick wall, a tripod, an L shaped yardstick (to make sure I am perpendicular to the brick wall). What else?

[btnapa]

What else?

Forget about brick walls!! Go out there and shoot some real world images. I own the 28-105. It pretty much retired my FA Limited trio (31, 43, 77) because the quality is fantastic and the zoom is very convenient. It is not as fast as the primes but it is perfectly fine in outdoor situations. I have shot a lot of keepers with that lens and my K1.

[madison_wi_gal]

Forget about brick walls!! Go out there and shoot some real world images. I own the 28-105. It pretty much retired my FA Limited trio (31, 43, 77) because the quality is fantastic and the zoom is very convenient. It is not as fast as the primes but it is perfectly fine in outdoor situations. I have shot a lot of keepers with that lens and my K1.

What might have gotten lost in this new thread is that I have a refurb 28-105 that *if bad* I can return before June 8th. I rented a FF camera to test this exact lens for defects.

[gatorguy]

What might have gotten lost in this new thread is that I have a refurb 28-105 that *if bad* I can return before June 8th. I rented a FF camera to test this exact lens for defects.

Oh.

In that case spend part of a morning doing the testing just as you described it. Sounds properly set up to me.

Then spend the next 5 and 3/4 days getting out and just shooting as suggested by @btnapa, playing with every lens you have, whether it be intended for crop or full-frame.

[pepperberry farm]

I'd suggest a short period of testing with brick walls, etc.. but the rest of the time, use it as you intend to...

if it's going to be a walk-around lens for you, I'd spend the remainder of the rental time doing just that....

[biz-engineer]

What else?

Not sure about brick wall tests. Brick walls don't contains very fine details and the test is sensitive to camera position due to depth of field.
If testing on a wall, I'd use news paper pages with lots of text to evaluate relative sharpness.

I'd suggest.

- auto-focus and manual focus at infinity distant line of trees at the horizon in the diagonal of the sensor, camera rotated at an angle, compare extreme corners and center
- focus at nearest distance, check that the lens can focus versus lens spec.
- center auto-focus accuracy at mid distance vs live view
- check each aperture settings in AV mode, from wide f3.5 open to max f22/f29, check that exposure is correct

[Wheatfield]

Brick wall tests are generally done for one reason only, which is to check for barrel, pincushion or moustache distortions. I'm not sure how important a brick wall test is anymore since often those lens problems are automatically corrected either in camera or during raw conversion.

[m96]

I'm not sure how important a brick wall test is anymore since often those lens problems are automatically corrected either in camera or during raw conversion.

Yes, and more importantly, those distortions are part of the lens' optical design and not something that varies from copy to copy.

I think a brick wall will not be the best tool to find out if your zoom is decentered. The effect should be more pronounced, the farther you focus, and brick walls get awfully tiny in the frame once you are focusing to 'infinity'.


I would simply take simple landscape shots of a forest and pixel peep its content. Center sharpness falling going towards the edges nonwithstanding, you should make sure the trees on the left hand side are equally sharp to the ones in the RHS.


Because you're testing a lens and not the camera, I would definitely make my test shots manually focused using the live view to eliminate potential AF issues with the K1ii and the zoom. The same goes for brick wall/ newspaper shots.

[UncleVanya]

My previous post got a bit sidetracked since I only had an APS-C to test my new (refurb) 28-105. I now have a K1-II for 6 days from Lensrentals.

So: I have a brick wall, a tripod, an L shaped yardstick (to make sure I am perpendicular to the brick wall). What else?

How to check how decentered your lens is - phillipreeve.net

---------- Post added 06-01-23 at 04:48 PM ----------

And:
How to Test Your Lens | B&H eXplora

---------- Post added 06-01-23 at 04:49 PM ----------

And… Lens Rentals | Blog

[sb in ak]

Go out and take the photos you’re passionate about and see how it handles. You can probably always find brick wall test raw files online.

FWIW, my K3-3 feels pretty much on par with my D850 in terms of dynamic range and high ISO performance. The D850 just has a higher res. It has me wondering if I really need a ff camera but the ability to print and crop big has its perks.

[madison_wi_gal]

Go out and take the photos you’re passionate about and see how it handles.

OK, my favorite truck garden awaits.

[RICHARD L.]

I have been using this DFA 28-105 mm HD zoom for 5 years with my K1 and there is no better landscape lens around. The best aperture is f/11 at any focal length.

[Paul the Sunman]

One issue to look out for with the 28-105 on the K1 is mirror slap. That particular combination, perhaps because of the moderate weight of the lens, is prone to it between about 1/100 s and 1/200 s on some bodies (not all it seems).

[madison_wi_gal]

One issue to look out for with the 28-105 on the K1 is mirror slap. That particular combination, perhaps because of the moderate weight of the lens, is prone to it between about 1/100 s and 1/200 s on some bodies (not all it seems).

Thanks, I have it on the rental now. Quite the chonker combo. Just went through all the recommended settings.

[MarkJerling]

How to check how decentered your lens is - phillipreeve.net[COLOR="Silver"]

That is so incredibly simple! Thank you for sharing.