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02-11-2014, 09:39 PM   #61
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QuoteOriginally posted by bass3587 Quote
Hmmm I wonder how the Tamron 28-75mm lens would do with this camera since it's a full frame lens?
I have one on order in A mount to use with an LA-EA4 adapter. Malfunction has just put up a pic in the A7r picture thread with the Pentax version too.

02-11-2014, 09:49 PM   #62
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Thanks for this terrifically informative and illuminating thread, Pinholecam! I was especially taken with the shots you too with the 77.
03-04-2014, 07:39 PM   #63

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Have not had a chance to take more trial photos.
Not because I've not been taking photos, but to bring out a specific lens and shooting them in specific f-stop settings in sequence so that I can easily remember for posting up is kinda hard, since some photos are not suitable for f5.6 or f8 shots for example.

For reference of shots with Pentax lenses that don't need to be in f4, f5.6, f8, I started a Lens Club for that here :

I also found 2 detail reviews of Pentax lenses on a FF here :
DFA100/2.8 macro WR - SMC Pentax DFA 100mm f/2.8 Macro WR on Sony A7R : ERPhotoReview
DA*55/1.4 - SMC Pentax DA* 55mm f/1.4 on Sony A7R : ERPhotoReview
03-23-2014, 01:37 AM   #64

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Managed to squeeze in some time to run through the FA*24/2

at f2

Pretty decent at f2 in the centre area.


Sharpens up well in the central area.
To me, its got pretty decent OOF rendering considering that its a 24mm, though it gets busier nearer the edges (again, can be common on other fast 24mm)
On aps-c the bokeh had looked 'all good' since it was using this less busy central area.



Centre area is sharp, decent edge sharpness, but could be better considering its FA* status to me.
Generally quite similar in the sharpness aspect to the K24/2.8 with the only advantage that it does not have noticeable corner vignetting (the K24 has a very slight one)
However, in terms of sharpness throughout the frame, I think its more or less close to many similar 24mm, except the very best (and pricey ones)
I also get a feeling that its not a lens that was designed with far focus and sharpness as a primary goal.
Perhaps it was intended more as a general lens with f2 (shallow DOF ) capability.
Anyone knows? (eg. like based on the brochure material of the lens )

Last edited by pinholecam; 03-23-2014 at 01:52 AM.
04-11-2014, 11:17 PM   #65

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Lets throw something different into the mix.
The DA40XS is not a FF lens.
There have been some good work done on film to show that it works on FF.
So does it really work on FF digital?

I managed to get some shutter therapy time during lunch to get this tried out.
The aperture settings are a 'guesstimate' based on how the aperture closes down wrt wide open diameter and the lever tacked on with blu-tack.

At f2.8

Generally, its ok, to me, very sharp in the centre.
Duh... we all know that since we use the centre on aps-c too.
Edges are soft, but I find that often, when shooting at f2.8, the subject placement won't be at the edges.
FF lenses can be soft too on the edges wide open (but, yes, its softer on the DA40XS there imo)

At f5.6

Very sharp for most of the frame.
Corners and extreme edges will still be a bit soft.

At about f8

Generally sharp all the way, very acceptable on the edges.
The corners don't get better though, a bit smeary, but its really just the extreme last bits of the corners, imo.

To me, I'm pretty happy with the results.
f2.8, I generally don't care for sharpness throughout the frame.
Usually, only the central and 'rule of thirds' area needs to give good sharpness to see the picture thru.

f5.6, I think the sharpness is there, but the user will need to be careful on what is being shot.
If sharp edges are needed, then perhaps f8-f11 will be much better choice.

f8, I think the DA40XS did fine.
The last bit int he corners are the only bits that are considered bad to me.
Thats either of little relevance for most photos or a little 'crop for composition' will take care of it.
Its not so bad that its going to affect the user when he/she composes in the frame imho.

Considering that Pentax did not every say this was a FF lens, I got nothing to complain here.
Most aps-c counterparts of the 35mm-50mm-60mm range on the Sony aps-c system vignette physically, needing elaborate work arounds.
So to me, I'd put my hands to applause the usability of the DA40XS on FF.
Given its remarkable size, I will be sure I will be using this lens often enough.

Last edited by pinholecam; 04-12-2014 at 02:16 AM.

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