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05-15-2016, 12:43 AM   #16
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QuoteOriginally posted by scopedude Quote
It's meant to be a practical way to test the lens.
Sure.

The method I proposed takes a bit more time but is rather practical as well.

QuoteOriginally posted by scopedude Quote
There is a grid in K1's viewfinder that would really help.
Using the grid for alignment is a nice idea.

However, you are then relying on the fact that the grid has been aligned with 100% precision. Imagine a slight slant and then you'd not be aligning your camera correctly. Viewfinder elements are typically not calibrated with utmost precision because they have no impact on the final image.

Therefore, I'd be cautious with this approach.

Also, you'd want it to apply in portrait mode as well. Otherwise you might be missing out on some vertical degradation.

QuoteOriginally posted by scopedude Quote
Pentax people came to my office with 2 K1s and 2 28-105s, and some other lenses so I had to decide which one to take home.
How nice of them.


QuoteOriginally posted by scopedude Quote
I've been doing it for years after getting less than ideal samples (many of them) from Canon and Zeiss ZE/ZF.
Sure.

I always check my lenses as well. No matter the manufacturer, there are always subpar copies. Recently a shop assistant tried to tell me otherwise ("Does not not happen anymore these days...") trying to explain why I wouldn't be able to return a lens that I found to be wanting. Guess what, I didn't buy the lens there.

05-15-2016, 03:10 AM   #17
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Well, that is my method for testing the lens in a short time, at least I know which one to take (more or less) - but it's certainly helpful to buy in a store that is willing to be 'flexible'. I have good relationships with the distributors here, so I'm getting the first K1 - and it will be launched later this month. They also left some 'goodies' for me to try.

Anyway, I just tested the 28-105 again today, so far so good. It's a very good lens, at 28mm WO the corners are already reasonably sharp, and at f/8 (throughout the range) I have no complaints
05-15-2016, 12:47 PM   #18
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All of my FA lenses needed an adjustment of -5 to -8 according to Lens Align. At close focus, except the FA43, this seems to be correct. Need to test it more.

One thing though: I have a permanent +0.7EV compensation dialed in. This seems to be correct as I don't get overexposed images. Camera is badly underexposing with all the FA lenses.
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05-15-2016, 03:31 PM   #19
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QuoteOriginally posted by MadMathMind Quote
Camera is badly underexposing with all the FA lenses.
That is strange. Did you add a comment on the "issues" page?


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05-15-2016, 04:19 PM   #20
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QuoteOriginally posted by MadMathMind Quote
All of my FA lenses needed an adjustment of -5 to -8 according to Lens Align. At close focus, except the FA43, this seems to be correct. Need to test it more.

One thing though: I have a permanent +0.7EV compensation dialed in. This seems to be correct as I don't get overexposed images. Camera is badly underexposing with all the FA lenses.
By badly, do you mean 0.7 stop? Or is the 0.7+ adjustment just to get nearer "proper" (per the histogram) exposure?
Because less than a stop would probably be "conservative" metering rather than "badly underxposed" metering imo.
05-15-2016, 06:08 PM   #21
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QuoteOriginally posted by kp0c Quote
By badly, do you mean 0.7 stop? Or is the 0.7+ adjustment just to get nearer "proper" (per the histogram) exposure?
Because less than a stop would probably be "conservative" metering rather than "badly underxposed" metering imo.
They are the same, no? Each stop is 1EV, so a +0.7 exposure compensation value is equivalent to the camera underexposing by 2/3s of a stop.

And the +0.7 isn't a "perfect exposure" by any means as I still boost it in post when I apply contrast, etc. Still, I'd expect better metering out of the 86k sensor than my 77 segment K-5IIs.

It's also possible that there's something wrong with my unit. I do most of my shooting in manual mode anyway with flashes and an external meter so it's not the end of the world, but surprisingly and a bit annoying.
05-16-2016, 06:24 AM   #22
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What software are you using to process your images? It could be the software is not reading the image data correctly and lowering the exposure by approximately -1. So, you compensate for this by adding +0.7 to your exposure in the camera?
05-16-2016, 09:21 PM   #23
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QuoteOriginally posted by 6BQ5 Quote
What software are you using to process your images? It could be the software is not reading the image data correctly and lowering the exposure by approximately -1. So, you compensate for this by adding +0.7 to your exposure in the camera?
Lightroom.

But I shoot RAW+JPEG (mostly for preview purposes). Without the +0.7EV, the in-camera JPEGs come out way too dark.

I do find I have to compensate with additional exposure (+0.5 or less usually) in processing after contrast is added, but that makes sense because I add a lot and that usually darkens the image by a small amount.

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