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IQ180 vs Up-Res A7R2

gerald.d

Well-known member
Gerald insists that CCD is good enough for that area (post here). On the other hand, my experience with CCD agrees with your statement here. Would you be able to share RAW files in this area (i.e. long exposure but not too long) to see the shadow recoverability, for a comparison between the 80MP Dalsa and the A7R-II?

Originally I speculated that in the 30 second territory the A7R-II could offer more details in the shadow than the IQ180, but now it appears that the A7R-II performs rather disappointing at 30 seconds when compared against its predecessor A7R.
No I don't.

Stop deliberately conflating what I was discussing with a totally different subject.
 

chrismuc

Member
Gerald insists that CCD is good enough for that area (post here). On the other hand, my experience with CCD agrees with your statement here. Would you be able to share RAW files in this area (i.e. long exposure but not too long) to see the shadow recoverability, for a comparison between the 80MP Dalsa and the A7R-II?

Originally I speculated that in the 30 second territory the A7R-II could offer more details in the shadow than the IQ180, but now it appears that the A7R-II performs rather disappointing at 30 seconds when compared against its predecessor A7R.
I will do some comparison shots and post raws, just takes a few days because I am about to travel.
But IMO one would have to compare for example

Sony A7R-II at ISO 100 30s
vs
IQ180 at ISO 35 with 90s.

And there the Sony will be sure better than the Phase. If using ISO 100 on the Phase (without 1.5 stop overexposure;-) , the sharpness on pixel level is already lower than at ISO 35, so I don't use it.

Btw., I considered to get the original A7R to accompany my IQ but I very disliked the quality appearance of the camera body and the user interface, plus the shutter vibration topic. In all three regards the Mark II is a big improvement.
 

gerald.d

Well-known member
Unless I am missing something the FOV on the IQ180 - after croping out the vignetting - will be approximately the same as the FOV on the Sony A7rll and the pixel dimensions are approximately the same. If the FPS is the 'only' system available then I see your point..... but if it were me I would mount that lens on an A7rll.

Victor
Yes. You are missing something rather obvious.

With the lens centered, the image circle just about fills the IQ180 frame.

Which is equivalent to the field of view of an 11mm lens on 35mm.

As I said before. Until the introduction of the Canon 11-24, no other lens/sensor combination provided such a wide field of view.
 

ErikKaffehr

Well-known member
Hi,

I have seen some reports indicating that vignetting and cross talk is much less with the BSI.

Best regards
Erik


Doesn't it depend on the lens being used - assuming we're talking about getting good results from shifting, rather than just being able to shift ?

The question is: does the new type of sensor used in the Sony behave as badly as the one in the IQ180 with large shifts where the angle of light hitting the sensor at the edge of the IC is acute ?

Since I've yet to hear anything about how it performs in such situations (and the BSI sensor design is predicted as behaving well with light striking it at an acute angle), I wouldn't reach that conclusion just yet.
 

gerald.d

Well-known member
The Rodenstock HR-W lenses are just a cut above any other lens I have used, it is no contest. (Well, the Cine Leica Summilux-C lenses are another story, but I have yet to see one used for still photography. They look AMAZING on a RED or Alexxa camera though :) ).
I'll see if I can fix that :)
 

f8orbust

Active member
And I'm sorry, but the IQ180 does NOT behave "badly" when paired with good lenses such as the Rodenstocks.
Never said it did.

I said performance is dependent on the lens being used. Just because all the latest R/S (RF) design lenses are good (however you define 'good') does not mean that all good lenses are R/S (RF) designs.

It's been common knowledge pretty much from day one that the sensor in the IQ180 behaves badly when shifted with good lenses from Schneider (and no, a lens doesn't suddenly become 'bad' because it won't play ball with a particular sensor). Which is a shame, because the S/K WA designs (in particular) have large ICs that you might want to perform large shifts with.

This is why the emerging BSI technology is important, since it promises to behave well with all lenses.

Jim
 

vjbelle

Well-known member
Yes. You are missing something rather obvious.

With the lens centered, the image circle just about fills the IQ180 frame.

Which is equivalent to the field of view of an 11mm lens on 35mm.

As I said before. Until the introduction of the Canon 11-24, no other lens/sensor combination provided such a wide field of view.
With the lens centered there is a lot, to me, of vignetting. Once that vignetting is cropped out the image is almost identical to the Sony image - other than format dimensions. If the vignetting is included to calculate FOV then, of course, the FOV is increased. BUT the vignetting has to be cropped out to get a usable image - at least for me. The first image is the lens centered on the FPS/IQ180. The second image is the cropped version. The third image is the Sony A7Rll with the same lens. What am I missing? If the lens is shifted on the IQ180 to eliminate vignetting the image becomes larger and field of view increases. BUT..... I can duplicate that with the Sony. Tell me what is gained?

Victor
 

Attachments

ErikKaffehr

Well-known member
Thanks for the links, they are informative.

Best regards
Erik



Hi, many thanks for sharing the RAW files! I can see that for your shutter speed the A7R-II does have some advantage in terms of shadow recovery. By stitching the A7R-II surely yields more details than the IQ180. Why do you get a black circle in the IQ180 file? The 17mm TS-E should be able to cover the whole sensor.

However, for long exposure shots, the A7R-II may not be a good choice.

For long exposure shots:

A7R-II performs even worse than Canon 5DSR
A7R-II heats up quickly during long exposure
A7R-II darkframe comparison (RAW files) against 5DSR and other Sony sensors
A Chinese review of A7R-II doing poorly in long exposure

Base ISO or high ISO, the A7R-II is not suitable for long exposure. You might even get better image quality with your IQ180 in the 10s-120s territory.

Based on the comparison between A7 and A7-II, i.e. no degradation due to 5-axis IS, it is probably true that BSI sensors are not suitable for long exposure. If it's true then it's such a shame that the Rodenstock and Schneider wide lenses cannot be resurrected by a perfect CMOS digital back based on BSI...
 

rhern213

New member
I agree with vjbelle regarding my original point of this being a print IQ test.

The point on FOV is correct, however because you need to crop out the outer 1/4 to 1/3 of the entire image, you loose pretty much all of the resolution advantage of the IQ180 for printing purposes. In this regard the advantage of the IQ180 is pretty much nill.

With the lens centered there is a lot, to me, of vignetting. Once that vignetting is cropped out the image is almost identical to the Sony image - other than format dimensions. If the vignetting is included to calculate FOV then, of course, the FOV is increased. BUT the vignetting has to be cropped out to get a usable image - at least for me. The first image is the lens centered on the FPS/IQ180. The second image is the cropped version. The third image is the Sony A7Rll with the same lens. What am I missing? If the lens is shifted on the IQ180 to eliminate vignetting the image becomes larger and field of view increases. BUT..... I can duplicate that with the Sony. Tell me what is gained?

Victor
 

gerald.d

Well-known member
With the lens centered there is a lot, to me, of vignetting. Once that vignetting is cropped out the image is almost identical to the Sony image - other than format dimensions. If the vignetting is included to calculate FOV then, of course, the FOV is increased. BUT the vignetting has to be cropped out to get a usable image - at least for me. The first image is the lens centered on the FPS/IQ180. The second image is the cropped version. The third image is the Sony A7Rll with the same lens. What am I missing? If the lens is shifted on the IQ180 to eliminate vignetting the image becomes larger and field of view increases. BUT..... I can duplicate that with the Sony. Tell me what is gained?

Victor
Frankly, I don't think you understand what you are looking at or discussing at all. How can you possibly not see that the images you quote in your post are shifted substantially?

I'm not sure how much more simply it can be said than "unshifted the Canon 17 TSE covers the IQ180 sensor".

And I'm getting extremely bored with having to say it.
 

vjbelle

Well-known member
Frankly, I don't think you understand what you are looking at or discussing at all. How can you possibly not see that the images you quote in your post are shifted substantially?

I'm not sure how much more simply it can be said than "unshifted the Canon 17 TSE covers the IQ180 sensor".

And I'm getting extremely bored with having to say it.
??????? What???? Please explain the first image in my post - the one with all of the vignetting. That image is a centered 17mm TSE on an FPS with an IQ180 back. Sure doesn't look to me like the sensor is covered. I'm not saying that the image circle isn't large enough to cover the IQ180 sensor but that the captured image isn't. To take advantage of the large image circle the lens must be shifted and the resulting files stitched. The same thing can be accomplished with the Sony.

Victor
 

gerald.d

Well-known member
Never said it did.

I said performance is dependent on the lens being used. Just because all the latest R/S (RF) design lenses are good (however you define 'good') does not mean that all good lenses are R/S (RF) designs.

It's been common knowledge pretty much from day one that the sensor in the IQ180 behaves badly when shifted with good lenses from Schneider (and no, a lens doesn't suddenly become 'bad' because it won't play ball with a particular sensor). Which is a shame, because the S/K WA designs (in particular) have large ICs that you might want to perform large shifts with.

This is why the emerging BSI technology is important, since it promises to behave well with all lenses.

Jim
My sincere apologies - the crucial bit in your post "where the angle of light hitting the sensor at the edge of the IC is acute ?" somehow didn't register.

I stand corrected on that point.

Kind regards,


Gerald.
 

gerald.d

Well-known member
??????? What???? Please explain the first image in my post - the one with all of the vignetting. That image is a centered 17mm TSE on an FPS with an IQ180 back. Sure doesn't look to me like the sensor is covered. I'm not saying that the image circle isn't large enough to cover the IQ180 sensor but that the captured image isn't. To take advantage of the large image circle the lens must be shifted and the resulting files stitched. The same thing can be accomplished with the Sony.

Victor
You picked them in an attempt to support your argument. You explain them.

Here's one to support mine.



17TSE. FPS. IQ180.

One frame.

Unshifted.

Uncropped.

No keystone correction.
 

vjbelle

Well-known member
The images I posted were from the files made available in post #37. You can download them for yourself and see for yourself.

Victor
 

vjbelle

Well-known member
Alpa made available a document that outlined the image size that would result from using various lenses including 35mm lenses. For the life of me I can't find it in my documents or on the Alpa site anymore but when 35mm lenses were used, via various adapters, the resulting pixel dimensions for phase one backs were compiled in a table. They were reduced as compared to a medium format lens because the lens simply wasn't able to fill the sensor completely. If I can find that anywhere I'll make it available.

Victor
 

vjbelle

Well-known member
Graham..... that is not the doc. I have seen that doc and it, for sure, shows that the 17mm TSE covers the sensor with minimal vignetting. The doc I'm looking for is not on their site anymore. I think that something is surely amiss. The poster that provided the downloads (post #37) surely labeled everything and the downloads are accurate raw files - in that they are Phase files and Sony files. I have relied on those files for my posts - and have also relied on my recollection of the doc that was provided by Alpa. If I had all of this stuff then this would all be moot as I would know for myself. I have no reason to doubt Gerald but, again, something is surely amiss. Why would the poster provide a file that is not accurate? Why is it different than Gerald's in the fact that it is very vignetted? What is going on?

Victor
 

GrahamWelland

Subscriber & Workshop Member
I can't say. I have the 17, 24 & 45TSE lenses and FPS but cropped IQ150. The vignettes image from Chris almost looks the vignette I'd see with my 45mm. With the 17TSE I don't get vignetting like that at all even with rise/fall.

I don't know ... The raw is pretty self evident but I haven't seen that with my 17tse and nor would alpa or Gerald's image suggest that it should be so bad.

hmm, just wondering if Chris shot the 17TSE with the lens shade on the FPS?
 
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daf

Member
To the OP:
nothing new here, I mean 40/45mpx mfdb has been around for long now...so if you only need 40mpx then you could have bought an iq140 or a p45 instead of the iq180 ...
If you need 80mpx then 40 will never do the job...as if you need 40 then 20 will never do it too!

To vjbelle: it is clearly a shifted image probably by 8mm ...
(kind advice: search for horizon�� )
 

vjbelle

Well-known member
17TSE. FPS. IQ180.

One frame.

Unshifted.

Uncropped.

No keystone correction.
Gerald, I have come to the conclusion that you are completely right. The image circle from the 17mm TSE covers the IQ180 Sensor..... just covers it. The raw file that I downloaded from post #37 has to be erroneous. I wish that poster could provide some more insight.

Victor
 
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