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Background:

I do landscapes but I started out this inquiry to try and understand why my wildlife and portrait photos at F4 70mm on my 24/70 FE were often blurred, my wifes RX100 took a sharper shot so I used that to compare,

Its been a little exhaustive doing all this pixel peeping etc. but I have learned a lot, the A7r is my first real DSLR after owning a NEX3, after shooting with it for 18 months now this investigating has helped me understand it and my lens strengths and limitations, I can condlude my investigation in this post.

 

This post is a follow on from http://www.sonyalphaforum.com/topic/3691-rx100-sharper-than-24-70-fe-70mm/ I could not add more images to that post so started a new one.

 

Findings:

1) As stated in the title, there is no doubt to me now that the Rx100 MK1 at its full focus range of 37mm (100mm equivelent in full frame) and max aperture of F4.9 is sharper than the 24/70FE at F4 70mm, and any F4 zoom range of the 24/70.

The 24/70 is sharper at F8 and I know there are many benefits of the A7r image, color, pixel density etc, but its just not that sharp at F4.

 

2) The 16/35 FE is worse than the 24/70 at F4 at 24 and 35mm (not suprising as I dont believe any super wide angle lens should not outperform or match a 24-70) It was on par maybe very slightly less sharp at F8 at 24 and 35 than the 24/70.

 

3) I can rule out shutter shock as a cause as I have compared a 24/70FE 24mm at F4 and F8 below, I used a Hoya HD ND to get the same SS, F8 is tack sharp so the blur at F4 cant be caused by shutter shake.

 

4) My images at 70MM have been poor for a few reasons, in an attempt to prevent blur at 70mm shoooting portraits or wildlife encounters handheld I have done the following to increase shuttter speed to avoid blur,

  • Shot at F4
  • Increased ISO

Given the 24/70 at F4 is kinda blurry from a tripod the degradation from increased ISO above 600 was extreme, and at lower ISO (1-200) SS goes as low as 1/45 outdoors under cloud or in shade, then camera shake can make it blurry.

So its basically pretty hard for me to do handheld portraits or wildlife shots on the fly unless I am in direct sun to bring the SS up without the help of ISO.

 

Conclusion:

Thats a little disappointing, maybe you pros out there are laughing at me as its obvious to you not to even try 70mm handheld with a slower F4 lens, but I had hoped I could do some basic stuff, truth is I should use my wifes RX100 for these kind of shots. This is not an attack on the 24/70, its great at F8 and I get the manyother benefits other than sharpness, just frustrating thinking i need anopther lens for handheld mid telephoto type shots.

 

I have a few questions:

  • Any suggestions? ( I now think I am better shooting 70mm at closer to F8, even if its way underexposed then recovering the image from raw, I will try that bit its hardly a goodsolution)
  • Is this normal for this or similar full frame DSLR lenses at wide apertures?
  • Does anyone still think my lens is a bad copy? I am thinking not as my 16/35FE is similar at F4 but please reply if you think so.

 

One last test I hane not done is in full sun, F4 vs F8 at 70mm, same SS using an ND,

The full sun speeding up the SS above 1/250 to rule in/out camera shake, but I believe I have done that anyway in these tests, and im over this. its hard work, so if anyone else wants to try with this with their 24/70 FE and post here be my guest.


 

 

F8 1/4 ISO100 70mm (24/70 FE) crop 100%

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This is tack sharp,

 

 

 

 

F4 1/4 ISO100 70mm (24/70 FE) Hoya HD Variable ND crop 100%

Not as sharp as F8 at all, now I know this is not bad, but this is from a tripod, remote release, shooting handheld or with increased ISO seriously degrades images at 70mm F4

 

 

 

 

F4.9 1/2 ISO100 100mm RX100MK1 crop 100%

 

Interesting the color change, both cameras are on standard creative style. BUt this is way sharper than the other F4 shots.

 

 

 

F4 1/4 ISO100 24mm (16/35 FE) Cokin HD Variable ND crop 100%

I have been curious which lens I am better shoooting at with between 24 and 35mm, My 24/70FE or my 16/35 FE, its clear the 24-70 is better but not by much.

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Thanks for your reply, but I am not sure I follow you, why would I crop the a7r 35mp sensor image less than the smaller RX100 20mp, Did you mean the other way around as that does not even anything it broadens the difference?

 

Re focal length, earlier in this review (it's in another post, link at the top of this post) I used the rx100 at 70mm equivalent in the same comparison, it performs even better so as suggested by another poster here I used its max focal length where it is weaker to match it with the 24/70 at 70mm where it is weakest.

 

No matter how I look at it the RX100 beats the 24/70 FE for clarity and sharpness at F4 vs its lowest aperture on every focal length but none more so than 70mm. But as stated this is just at F4, it performs much better at F8.

 

I know I can't evenly compare these cameras, but I was just making a point, that the 24/70 at F4 is weak so I am wondering....

 

 

Is this normal for this or similar lens?

 

Do I have a bad copy, should I send it back?

 

Can anyone else with this lens get a tack sharp F4 image?

 

 

 

 

Steve,

Lawlors Landscapes

www.lawlor.me

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lenoindex is saying, you use 100% crop to compare two sensors with different resolutions, which is wrong.

 

Imagine you have two copies of the same picture, one is 100x100, the other is 200x200. Now you both zoom them to 100% crop, and your window size is 50x50.

With the 100x100 copy, you are seeing 1/4 of the picture area. With the 200x200 copy, you are seing 1/16 of the picture area. How can you compare them?

What you should do, is to zoom your pictures so that you see the same percentage of the picture area when comparing.

 

In your particular case, your RX100 looks a bit sharper, but it is running at 100mm equv. Which means its captures less things in the photo. You should zoom it to 70mm, take the same picture, and go to your computer and magnify the photos so the same object looks about the same size. 

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Ok thanks for explaining Steve,

I should have been clearer, maybe my statement of 100% crop was misleading.

 

1) In the images I compared above I moved my tripod to ensure that both images covered the same surface area

2) I zoomed just over 1:1 in lightroom (i though this was 100%) so the crop was equal on each image, I am not looking at 1/4 of one picture vs 1/16 of the other.

 

It is my understanding at this point that the Rx100 image is the same as the A7r but with less pixels due to its smaller sensor and with F4.9 vs F4 as 4.9 is the min at 100mm on the RX100. So this should mean that the RX100 image is at a disadvantage to the A7r, correct me if I am wrong?

 

3) In an earlier test of the same comparison I had the Rx100 at 70mm equivalent (http://www.sonyalpha...-24-70-fe-70mm/)

I changed it to 100mm in this post (but same surface area) to try and even things out as the Rx100 was sharper at 70mm equivalent,

another poster pointed out that this was not an equal comparison as the A7r was on full focal length which is a weakness and to compare more equally i should put the RX100 at full focal length and move the tripod to ensure it covered the same area.

 

So I believe I have done what you are suggesting, apart from bringing the Rx100 to 70mm equivalent and same Aperture as I know that will improve the Rx100 and widen the gap. please correct me if I am misunderstanding?

 

To be honest, I am over this comparison, If I can change the comparison to make the A7r look better at Fe 70, do let me know. Every way I look at it my 24/70 is weak at F4, not much of a problem in the images above but  try handholding at 70mm on a cloudy day and taking a photo of a bird in a tree, poor results. Low ISO and movement is an issue, ISO over 400 and it degrades considerably.

 

Maybe I should have used another title for this post but my point is,

 

I am a hobbyist developing an intimate knowledge of my kit, I know bigger apertures like F4 is a weakness for most DSLR lenses, I know my this kit is better for landscape qnd not meant at all for low light shooting  I am surprised at the not huge but significant difference in sharpness between F4 and F8,

 

Q1) So is this lack of sharpness at F4 normal, or is my lens copy bad or is the lens just bad, do I need the new Sony FE 2.8 to address this shortfall?

 

Q2) Can the dynamics of the Rx100 usually beat any dslr and zoom lens for sharpness at F4 mid telephoto, or is it just the combo I am using? I know this statement is against the DSLR religion but some fixed lens compacts may well be better all-rounders than a single lens combo like A7r 24/70 FE, they do macro better for example and the Rx100 is an award winning camera, but if that’s true I doubt anyone on here would admit it was better than a dslr let alone the A7r in certain circumstance;) The autofocus of the RX100 appeared way better than the a7r too nut I won’t start that analysis.

 

I hope my long replies don’t put anyone off, please reply with your views

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TBH, your long posts..are scary..you are definitely putting me off with your replies...but I still replied..see below..

 

I don't know why would you find it so rewarding or motivated to do all these pixel peeking practices, there are so many other important aspects of photography or lens quality should be taken into account, color tone, depth of field, noise, bokeh, rendering style blah blahblah.

 

To my eye and taste, when magnified, your RX100 photos looks harsh and produce rather unpleasant color tone, sharpness would be the least thing I would think when comparing the two system.

 

Also F4.9 of a 1 inch system equals F13 in FF in terms of DOF, subject isolation is a world of difference.

 

To sum up, I don't agree to your test methodology, but more importantly, the variable you are testing is definitely not a strength of the FE 24-70/4 - a all rounder standard zoom.

 

If sharpness is the only factor you find important, step down. and judging from your opinions, I think you really should try out faster primes, which will provide sharper image at even faster apertures, probably give the FE28/2, FE55/1.8, or FE90/2.8 and the new GM85/1.4 a try, and keep which ever fits your shooting style the most and shoot other staff with FE24-70/4 or RX100.

 

I do expect the GM24-70/2.8 much sharper than the FE zoom, if it is a purchase you can justify, definitely try it out too.

 

And for your question of whether to use 16-35 or 24-70 for the 24-35 FLs,

1. depending if you are shooting more 16-24 or 35-70;

2. I quite like the rendering and how it deals with flare of the 16-35, I never used the 24-70 but I don't expect it to be better than the 16-35. 

 

P.s. no offense, if you want to develop knowledge of your gears, you probably want to know both your a7R and rx100 are not DSLR's, and you should looking into difference and characteristics of different format size (FF, ASPC, 1 inch). But your finding of RX100 and FE24-70/4 produce similar sharpness at F4 vs F4.9 is interesting, but probably expected - check out DXO sharpness measures, 24-70/4 at 70mm F4, Sharpness is roughly 60%, and RX100 F4.9 at 37.1mm is roughly 55%, which is very similar - their tests are based on the same print size and focal distance etc etc.

 

Anyway...have fun shooting!

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Ok Thanks for your reply again Leonidex,

I agree, this pixel peeping is something I will only do once,

But it has been rewarding, I have learned not only that pixel peeping is for freaks and is quite exhausting...lol, but I needed to know why my handheld shots at 70mm F4 of nearby wildlife were so soft, I first thought increasing SS through higher ISO would help but that made it worse, now I know its a lens limitation, its a little disappointing but I will probably learn to live with it or work around by stopping diwn when i can, the softness is probably good for most portraits and I doubt I will buy a prime or another lens for anything but landscapes, maybe the 24/70- 2.8 but its huge for me so maybe not.

 

I agree there are many other aspects of a photo than sharpness, so enough of the comparing two different sensors, lets put an end to it, its a sharpness test and the same picture from both cameras with settings, scene, distance, crop etc. matching as much as is possible and its sharp on the RX and soft on the A7r at 70mm F4, nothing is going to change that.

 

 

More importantly I wanted my questions answered and I think you have indirectly,

Does anyone think my 24/70 is faulty or is this F4 softness on the end of focal distance normal?

Is this normal of a 24/70 at F4

 

Thanks for the DXO info, that suggests that my copy of the 24/70 is way underperforming if it should be 5 points higher in sharpness than the RX100 and clearly is not, maybe I should have it looked at as one poster suggested?

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Every lens i know of has some sweet spots and some big compromises at some aperture/distance/zoom position or combination of some of these. I should know, i have tried over 200 lenses up to now. Finding these compromises is now free since you can test all day long with minimal cost to you except your time.

 

Have you tried your 24-70 at f4.5 and f5.6 ? Sometimes a very little stop down increases IQ by a lot ( my old Minolta AF 24-85 f3.5-4.5 is very fuzzy at max aperture and sharpness gets great stopping down 1/2 stop at most focal lenghts. Some lenses are better at some distances or focal lengths in case of zooms and trying to do landscape at Max aperture of F4 will always create out of focus zones that you will then consider unsharp.

 

Most zooms ( even the new G Master at their horrific prices) will have some compromise somewhere and some will hate them for that but it is a fact of life that no human design can be perfect for everybody in all conditions. Some will be a little weaker at the shortest end, some at the longest, some at max aperture and min aperture and sometimes a little of all of this whatever the price you paid.

 

The idea is to try them or rely on other people's tests to evaluate the compromises facing us but with the advent of all the tweaking of pictures we see through Photoshop and the like that we are not aware from the testers out there, it is very difficult to believe all of the pictures i see from other users have not been improved in a way that i may not agree with to promote the supposedly great qualities of a particular lens out there. Sometimes i see pics that are so touched up and the user is so much promoting the great quality of his lens, i wonder if he is not trying to sell it by hiding its flaws through PhotoShop.

 

In this case, i find all of your crops a little unsharp and this could be due to camera movement during exposure. I have A7r and i do sometimes struggle with it at some shutter speeds that cause more motion blur than i expect. Do you have a TTL flash ? This would help minimize any camera movement on a test picture

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Thanks Michael,

Interesting that you consider the F8 ISO100 centre crops a little unsharp, I thought they were as good as it gets, they are a 1:1 zoom in Lightroom which is a lot.

 

I can rule out movement as the cause of the additional softness that occours at F4 over F8.

 

Yes I will step down to f5.6 and/or 60mm, but my its a pity to have to do this?

 

No other 24/70FE owner has let me know that at F4 70mm their lens is as soft, so I still don't know if this is common for this lens or if I have a bad copy, the drop off does seem a little extreme to me, I am asking a few others and will post here once I have an answer on this.

 

 

 

Steve,

Lawlors Landscapes

www.lawlor.me

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I think your test is completely flawed. If you want to test a lens then you have to isolate the lens so that nothing else is influencing the result. So set _everything_ else to values which don't impact image quality. Base ISO, SS 500+, use a simple resolution chart (print and mount on a piece of flat board) ... and remove the ND Filter. Use stable lighting (or cloudless day). Not sure what subject distance to use, 2m perhaps.

 

Then work from RAW files, since JPEG coming from A7 and RX100 are not comparable ... but the A7 and RX100 are not directly comparable anyway. Once you have the center shot taken, swivel the camera on the tripod and get corner shots of the target, and/or take shots of a distant object at each corner. That collection should give you some information about your Lens and it tolerances. Repeat for f4, 5.6 and f8.

 

Forget about the RX100.

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Thanks for the replies and all but enough with the testing, I was just making a point leading to my actual questions which no one is answering, does anyone have the 24/70 behaving the same at F4 70mm?

 

2 facts found here will not change under any conditions as I have tested most of them, my 24/70 is soft at F4 70mm and the RX100 is not. Forget all the techno jargon, imagine we are talking to some Joe soap on the street, he tries both cameras standing in the same place, zooms both to same field of view as F4 70mm on the 24/70 and snaps, when he asks why one is soft and another sharper when he zooms in, will you all say it's an unfair uneven test? You would get a funny look, because from a layman a perspective that will sound insane and from that perspective it's always uneven until you maybe disassemble them in a lab and make one camera from the two, but it is a totally even test from Joes perspective;)

 

It's my fault for naming this thread on comparing the rx100 and no matter how many times I tell people that's not the point of the post and repeat my questions, I have people defending the 24/70 against the rx100.....it's been an interesting converstation but maybe time to let it rest and help me inquire if my 24/70 is faulty or standard?

 

No offence to anyone, just trying to steer this in another direction:)

 

 

 

 

Steve,

Lawlors Landscapes

www.lawlor.me

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Why don't you actually post the images you are unhappy with, including links to full size images on Flickr (or Raw files). Right now how can anyone offer you an objective comparison when all you post are images of brick walls?

 

You can see a few samples here at 70mm and F4: http://www.kenrockwell.com/sony/zeiss/24-70mm-f4.htm also pay attention to the MTF charts towards the end.

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2 facts found here will not change under any conditions as I have tested most of them, my 24/70 is soft at F4 70mm and the RX100 is not. Forget all the techno jargon, imagine we are talking to some Joe soap on the street, he tries both cameras standing in the same place, zooms both to same field of view as F4 70mm on the 24/70 and snaps, when he asks why one is soft and another sharper when he zooms in, will you all say it's an unfair uneven test? You would get a funny look, because from a layman a perspective that will sound insane and from that perspective it's always uneven until you maybe disassemble them in a lab and make one camera from the two, but it is a totally even test from Joes perspective;)

 

 

 

There is a fundamental misunderstanding here of the relationship between Aperture and Sensor (size generally). Its OK to claim that an ignorant person would not know the difference,  but you will not further your own quest by taking the same position. This calculator is a good way to learn whats really happening: 

 

http://www.cambridgeincolour.com/tutorials/dof-calculator.htm

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Hey Timde, there is a fundamental misunderstanding of this post, who cares why the Rx is sharper at a specific setting, it does not matter.

 

What is of interest is why the A7r is not sharp and understanding if it's true that some lenses were made badly as some suggest? thanks for the image samples I will look at them tomorrow and provide links to my samples.

 

 

Steve,

Lawlors Landscapes

www.lawlor.me

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Sweet spots, pixel peeping, blah blah ...

just keep in mind that it is always

unappetizing to know what goes into

making the sausage, yet in our toadall

ignorance of those ingredients we find

the sausage very tasty !

 

"Lawlors Landscapes" ... the user name

tells me you like landscape shooting.

While this forum and some other are full

of pixel peeping landscape geeks who

spend waaaay to much on quality optics

please try to immunize yourself against

that virus. I have seen endless posts

featuring the leaves in the very corner

of the frame etc etc. While I can very

clearly see in these posts which lens

or which aperture renders the sharper

leaves, rocks, etc ... IOW the testing

procedure produces valid data ... I've

yet to see ANY landscape photo that

actually benefits aesthetically from

superior, or near ultimate, sharpness.

It just does nothing. Not that really

trashy lenses are suitable, but there

are hardly any of those around, as is

evidenced by the fact that certain

companies actually sell intentionally

trashy lenses for special applications

[LensBaby etc etc].

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The ultimate sharpness game played by

so many landscape geeks reminds me of

drag racing. It's a game of ever escalating

specs and hardware development devoted

to traveling, as fast as possible, along a

very short road to nowhere. You want

your landscape work to "go somewhere" ?

 

[say, "Yes".]

 

Put something such as a layer of plastic

freezer wrap over your lens. NOT to get

crazy soft effects. Just to get normal

looking shots while liberating your eye

and mind from the pursuit of ultimate

sharpness. Take extreme sharpness off

the table and you have nothing left but

color, light, perspective, intrigue, sense

of time/place/weather, and all that stuff.

 

And don't go removing your sharpness

attenuating device to do comparison

shots. If you use a very mild level of

attenuation your pix will LOOK sharp at

a glance. No intention here of using an

OBVIOUS loss of sharpness as some

sort of aesthetic trick.

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BTW, I actually DO check the performance

of my lenses ... but only for stuff that would

be visible without pixel peeping, stuff that

might interfere with presenting the subject

scene to non-geek eyes.

 

I check for degree of center hot spotting,

and what aperture fixes that. I check for

degree of focus shift from center to the

outer areas of the frame, and which way

it shifts. It's good to know how flare and

internal reflections behave at large and

small apertures. And some other stuff, but

it's all about rather "grossly visible" stuff. I

don't want grossly visible purple fringing

any more than a geek does. But if I hafta

pixel peep to find it, then who cares ...

Somebody else cares, but not me and not

ordinary audiences. Yeah, audiences. A

picture is a performance.

 

PS: I noticed your brick pix but I didn't

really look at them. Life is too short for

boring performances. [i realize they are

not intended to be otherwise].

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Hey Golem,

Actually we are looking at the 24/70FE specifically at 70mm F4, so not a landscape setting, rather for passing wildlife, handheld, prone to movement etc.

 

Timde,

I had read Ken Rockwells post before, few interesting points,

  • His 70mm F4 image was a bokeh test (search page for "at 70mm" to see the image of a mini wind antenna) so hard to tell if its sharp in the center, it certainly looks like it is, the dandelion and cob webb look crystal.
  • He does not comment on any soft focus at 70mm, just 24mm corners which I personally cant notice nor do I care that much about corners, but I do want my center sharp when it comes to wildlife. His MTF charts? dont refer to softness at F4 70mm
  • His other test of this lens here against two other 24/70mm is interesting, he slams the 24/70 FE stating that a6000 and equivalent lens is as good at 1/7 the cost, however I am not fussed about corner sharpness nor do I care if the aspc lens performs as good because I want the A7r for my other lens and future lenses so this does not put me off.

 

What drives to continue this inquiry is the multiple indications that others are not getting what I am at F4 70mm, and if I conclude that I will send my lens for testing, return or exchange it for another copy.

 

I am posting two photos in RAW & JPG of my wall as that was a controlled environment, the only variable between these two photos is shutter speed,

Earlier in this post I had used a variable ND to even SS on the F4 only to the F8 ones, that did rule out shutter shock as a cause as F8 was sharp but that softened up the F4 shots even more so this current comparison with differing shutter speed is about as equal as I can achieve.

 

F4 70mm jpg (8mb)

https://drive.google.com/file/d/0B2ut0--dO1o1VmJUMWhzVXBRZGs/view?usp=sharing

 

F8 70mm jpg (8MB)

https://drive.google.com/file/d/0B2ut0--dO1o1MzhaMmlQNWEyNzg/view?usp=sharing

 

F4 70mm raw (35mb)

https://drive.google.com/file/d/0B2ut0--dO1o1RFladDMzUW5makE/view?usp=sharing

 

F8 70mm raw (35mb)

https://drive.google.com/file/d/0B2ut0--dO1o1TjdYMGlhNXp2cFE/view?usp=sharing

 

 

Would be glad to have anyone's opinion

(but maybe we can skip the lectures that sharpness does not matter etc etc, I get that its just a part of what matters and in many types of photo it does not matter, but this post is inquiring specifically on sharpness)

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From what I have seen and read is that the 24-70 is not the sharpest at 70mm f4, and your findings confirm that (I haven't seen a 24-70 zoom that is not a little bit softer at the zoom end wide open yet). That is easy to comprehend. To get better results, simply stop down to f8, and as your samples show, it is very sharp at f8.

If you want more reach and/or higher sharpness, the 70-200 f4 is a good option.

I think that your results are in line with what you can expect for the 24-70 f4.

Going by the measurements of DXO, the 24-70 is softest at 70mm f4.

 

How can you conclude that the 24-70 f4 is better than the 16-35 @ 24mm without showing samples? It is hard to believe, because the 24-70 f4 is weak in the corners at 24mm, and in the center, the 16-35 is excellent too.

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Have you figured this out yet?

The a7r should run circles around the rx100 even with the 24-70. You have a weak link somewhere. Shutter shock? Poor copy of the lens? Malfunctioning camera?

I am not questioning the results you are getting. I m curious why. You need to troubleshoot to find the error.

The A7r has a superb error but shutter shock and poor technique canleadto subparresults. The 24-70 is also not the ideal lens for the a7r but unless the lens is flawed I think the error is somewhere else

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As per the EXIF on your RAW files

 

ISO 100, 1/8 sec shutter speed for the F 4 picture ?

ISO 100, 1/2 sec shutter speed for the F 8 picture ? If you used ND filter, it was not deep enough to keep things consistent.

 

Should be the other way around. I only see about 1 minute and a half between the 2 pictures

Did the lighting change that much between the 2 pictures ?

 

If on tripod, did you take OSS off ? If not it should be off when shooting on tripod

If handheld and the shutter speeds i see here are right, there are miracles OSS can not achieve

 

I suggested a flash picture in my earlier post, this would eliminate any camera shake or OSS under/overwork issue.

Or at east increase ISO to get closer to 1/70sec shutter speed ( 1/ focal length is a basic principle that should even apply with OSS to ensure better pictures mostly when testing)

 

I was looking at this evaluation earlier thinking about you: http://www.photojottings.com/sony-fe-24-70mm-f4-za-review

But his shutter speed at F4 at 70mm is 1/320 sec. This makes all the difference in the world

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Just a reminder to everyone that the issue I started off this post to research is why handheld 70mm F4 shots are soft, for passing wildlife on landscape hikes, increasing ISO made it worse, sure I will work around it at say 60mm f5.6 etc but you kinda need wide aperture and max tele to get even slightly close to wildlife with reasonable SS to prevent blur. I realize its prob not the right lens for this even secondary use, but I had hoped it would do better than its done, maybe unrelaistic of me but I am just a hobbyist learning.

 

 

Seeky,

Thanks for your feedback, interesting that someone thinks this is standard for this lens at 70mm open.

I did not test anything but center sharpness and to me the 16-35 and 24-70 were similar, it maybe looked like the 24-70 was marginally better but not by much.

 

Golfhov,

I am not sure why yet but the Rx was sharper, but only at the specified focus range wide open, the A7r did run rings around it at almost all other combinations and looks better for many other reasons than sharpness. Shutter shock was ruled out by doing F8 and F4 shots with an ND on F4 to match the SS, F8 was very sharp, F4 was even softer with the ND so not a great comparison but that does rule out shutter shock given SS was same.

 

 

Michelb,

Slight misunderstanding there, its a long post but earlier on I used the ND to match SS but realised that Hoys HD Graduating ND I was using was further softening the F4 shots so this was not an equal comparison, that did help me rule our shutter shock as F8 was sharp, but the raw files I posted I did not use the ND, therefore the only variance in these images was the SS.

 

No I did not bother turning OSS off as I tested that at the beginning of the first post of this 2 post discussion (link at the top of this post) and it made absolutely no difference between two identical images shot, maybe we should start another thread on that one, I know this makes a difference on other cameras, I don't think turning IS off on the A7r on a tripod makes a difference.

 

I tried changing ISO at 70mm F4 but given the image was soft, degradation of quality was extreme above ISO 400, it seemed amplified for some reason.

I posted to that very review on photojottings yesterday on this subject, awaiting response but yes, I have not yet tested this test in full sun high SS, but that's not realistic as I usually am shooting a bird in a tree from the shade so I don't care of that resolves it. I got about 1/45 to 1/90 shooting a bird in a tree recently, next time I will try iso 200, F5.6 60mm or something.

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I shot a test chart with 24-70 F4 and A7 when I received the lens, just to check if the lens is misaligned or not. I consider it is a good copy. I don't keep the shots but I remember my finding at f4:

1. 24mm, sharp in the small part of center and the rest of the frame is soft.

2. 35-50mm, is sharp in the center and just a touch softer near the edge. best performance at 50mm.

3. 70mm, soft at the center just like your copy and almost uniform performance for the entire frame.

 

So I think it is quite normal performance of 24-70 f4 at long end.

 

I also have the 16-35 f4 and I don't think the 24-70 is better at 24mm. Both lenses have almost the same sharpness in the center at 24mm f4, but the 16-35 has a lot better sharpness all the way to the edge.

 

At 35mm f4 it is a different story though. The 24-70 perform better at this focal length. 16-35 quite soft, just like how the 24-70 performed at 70mm f4.

 

I hope that finding could help you.

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Only just seen this thread.

The fe 24-70 is the lens with which i have been most disappointed by a flying mile. I bought one of the first copies made and had such high expectations of it.

My copy is dreadful at both ends of the zoom wide open and to be honest and it doesn't produce a quality at f8 that is acceptable for a zeiss badged lens on a high end 36mp camera (a7r).

I have the rx100 mk3 and it blows the lens out of the water in terms of sharpness at 24 and 70. A2 prints are superb.

For the a7r, 24 is a problemmatic focal length with legacy lenses and i have had no success.

I purchased the loxia 21 which is absolutely superb.

I actually use the pentax m 35-70 f2.8-3.5 which is excellent on the a7r and my mint copy only cost £70!!!!

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