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Credo 50 Review coming

dennishuang

New member
Guy,

Thanks for the heads up. I'm interested in hearing about your experiences with it and your opinions.

Regards,

Dennis
 

dougpeterson

Workshop Member
I was hoping that you could probably test your 28HR or 28XL on it for crosstalk issues. :mad:
Identical performance on a tech camera to an IQ250 or IQ150... 28XL is a no go. 28HR will be usable but with less movement than with other backs.

If wide angle tech camera use, with movement, is core to your need then none of the 50mp CMOS backs are the ideal choice.
 
Identical performance on a tech camera to an IQ250 or IQ150... 28XL is a no go. 28HR will be usable but with less movement than with other backs.

If wide angle tech camera use, with movement, is core to your need then none of the 50mp CMOS backs are the ideal choice.
Thanks Doug!

Do you have any rumors regarding the upcoming CMOS sensor in 645 fullframe size (around 54x40mm in size like the IQ260/IQ280)? If you would have to guess, roughly when would you expect to see announcement from Phase One? I currently hear about rumors expecting July 2015, which is just beyond the 12-month Investment Protection Plan of my IQ260. In such case it is probably best for me to sell my unit early.

Is there no yellow-banded new Rodenstock ultra wide angle lens announced during Photokina 2014? Does that mean wide angle movements on tech cameras are stuck with IQ260, with no future for a hope of CMOS from SONY?
 

dougpeterson

Workshop Member
Thanks Doug!

Do you have any rumors regarding the upcoming CMOS sensor in 645 fullframe size (around 54x40mm in size like the IQ260/IQ280)? If you would have to guess, roughly when would you expect to see announcement from Phase One? I currently hear about rumors expecting July 2015, which is just beyond the 12-month Investment Protection Plan of my IQ260. In such case it is probably best for me to sell my unit early.
It's only speculation based on experience and knowledge of the industry as a whole, and not inside information, but my guess is 2016 at the earliest.
 

Guy Mancuso

Administrator, Instructor
Started shooting this today and will continue with a tech cam the rest of the week. Not giving it away but I'm very impressed with live view on it and makes it very functional to use. Seriously after owning 5 backs I can't tell you shooting at ISO over 400 are unheard of and live view to boot makes this a Wow right out of the gate. I'm talking clean High ISO.
 

Guy Mancuso

Administrator, Instructor
I only have one on hand a Rodie 40mm with tilt adapter on a Alpa STC. I have the gear until Monday so some time to play with it. My main interest is how the New CMOS plays in this arena so far I can tell you it is much better than I thought a CMOS sensor could do. This really opens up the door to medium format. Its clean its easier to shoot and a very simple back in terms of use that is. I did not even look through the viewfinder of the phase body once yesterday. Just used live view the whole time because I could. Lol

I have the Alpa viewfinder that I'm not even going to put on. Eliminates any need for it or even a iPhone setup. Gotta love that right there

They even sent me a Disto and that will stay in the bag as well.
 

Paul2660

Well-known member
I fully agree that the CMOS brings a lot to the game, the use of the higher iso's as you mentioned. Key.

The 1.3 crop still gives me a bit of consternation, as having the full wide really makes a difference for me here in Arkansas.

It will be most interesting to see how the movements look, on the 40mm, at 12mm to 15mm of shift. Looking forward to your detailed review.

Paul
 

torger

Active member
From Doug's tests made with the IQ250 and the Rodie 40 you can often get good results in the whole image circle, but depending on subject you may get visible crosstalk artifacts (desaturation of colors and mazing in demosaicing) outside about 65mm image circle.

Depending on how important color and tonality is for the photographer, and how good the photographer is at detecting degradation of those, and how much shift range that is desired the appreciation of this sensor+lens combination will vary.

Doug's stitch test in the library is an excellent benchmark test that anyone can look at. The IQ250+40HR image looks great at first look, it's not until you start comparing with the IQ260 shot you realize that the color is not stable, it desaturates, and when you look at 100% you see that there are demosaicing artifacts here and there. Personally I see this as a big issue for a system at this level, but others can be more forgiving. To me color stability is more important than sharpness or even noise as you can see it on a distance, while sharpness and noise is a closeup thing, but another photographer may see things otherwise.

Anyway, as the Credo 50 uses the exact same sensor as the IQ250 I think there will be no new behavior to document with this lens combination. Ie at first look it will look great, and at a deeper study you see the limitations.

12-15mm of rise with horizontal orientation will most likely yield good results in most conditions with this lens. From Doug's tests I see quite good color stability (according to my eyes), but a little of demosaicing mazing. On a distance it will most likely look great. If you shift further to say 20mm you start to have visible loss in color fidelity, but if that happens to be a gray overcast sky it probably won't matter.
 

Paul2660

Well-known member
As Admiral Farragut said in the battle of Mobile Bay, "Damn the Crosstalk, Full Speed Ahead" :)

I feel that a lot of the issues can be corrected in post, not all but a lot of them. It's for sure an issue that each photographer has to work out.

The Rodenstock 40 HR-W should shift well into the 18mm range on the 1:3 crop of the IQ250, and hold excellent details. That's about the max I want tend to use and 12mm to 15mm is more the average.

Based on my experience with the Sony A7r and 40 HR-W:

In post, I have found, that to my liking, I can recover a lot of the loss in the greens and deeper colors, red, brown, yellow etc.

Where I have issues will be a solid blue sky on a 12mm shift with the 40mm here the blue tends to take on a hue issue that before C1 Vr 8 is hard to correct. If the sky has clouds to help break up the sky the "my eye" finds this a lot easier to work with. Now with C1 vr 8, and WB in the local adjustments, I find that I can work better on the images that show this effect.

Are they exact, no, but do they work? Yes.

The solid blue sky also tend to give me fits with the IQ260, not as bad as I noticed with the Sony, but again C1 Vr8 really adds to the equation to fix this.

Paul
 

Guy Mancuso

Administrator, Instructor
Okay guys sounds like some heavy shifting is needed and I'll go up to that cowboy town which has lots of sky and detail in the wood. No worries I share the raws too, so you folks can process as well. I will tell you this outside crosstalk stuff I'm very excited what I seen so far. I really had my doubts on MF CMOS but that's seems to be not the case so far.
 

Guy Mancuso

Administrator, Instructor
Let me add something here as I learned a few things yesterday. Don't assume even though they all use the same sensor that they act the same way. Each company or division of a company does all there own recipe on how these sensors perform on there back end. Most OEMs lock there engineers in a room to design based on the base sensor Sony fabricates to there own fine tuning to it. Each company or division may do things different than the others. This is stuff we as end users never know about is how the design process is done in those early stages of the sensor build. Sony only acts as a fabricator of the sensor but each company has there input on how they want that done. This stuff is honestly beyond my technical ability is to understand how that comes about and not always if ever public knowledge . We as end users may see differences when we finally output the files from different sources . So I hate to assume too much here
 

torger

Active member
Although I doubt it, the Sony sensors used Phase One / Leaf / Pentax / Hasselblad could have different CFAs which would lead to color differences even if the same profiles are applied. Long exposure performance surely differ as it's much about heat of the surrounding electronics. However there's a lot less black magic to integrating a CMOS than a CCD as CMOS delivers a digital signal while the CCD is analog. Thus I would expect less differences than for backs sharing the same model of CCD sensor.

What surely won't be different is crosstalk performance as that depends on the physical pixel structure, and I cannot imagine that that would be different, because that would mean delivering different sensor technology all-together. But well, it does not hurt to test! Excited to see the results.

When you do shift testing, I'd recommend to include a really extreme shift too like to the edge of the image circle so you really push it (say 30mm if your tech cam has that range). I would expect a quite mild onset of artifacts for medium shifts, possible undetectable in sky. Say if we get a test with 15mm shift and we see no visible crosstalk artifacts one could get to the conclusion that maybe it can do the whole image circle, but we would not know. So then it's better to also include one all the way to the edge so we really get the answer :)
 
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