Leaf Credo 60 and Technical Cameras

[Lobalobo]

Anyone know if the Leaf Credo 60 uses micro lenses? It is advertised as ideal for technical cameras and I've heard it said among photographers that Leaf Credo is well-suited for such use. Just wondering why, and lack of micro-lenses seems a possible reason. Thanks.

 

[torger]

Anyone know if the Leaf Credo 60 uses micro lenses? It is advertised as ideal for technical cameras and I've heard it said among photographers that Leaf Credo is well-suited for such use. Just wondering why, and lack of micro-lenses seems a possible reason. Thanks.

It does not lack microlenses. It's the same sensor across P65+, IQ160, Credo 60, Hassy 60 MP backs, the Dalsa FTF-9168C (https://www.teledynedalsa.com/imaging/products/sensors/area-scan/FTF9168C/), from the product sheet: "Micro lenses with wide angular response". However the microlenses are of a newer kind and not as "destructive" as they were on Kodak chips.

All those backs work well with the newer Rodenstock retrofocus wide angles unless you do something extreme (like shift to the edge and/or increase contrast maximally), and less well with Schneider Digitar wides, SK35 and SK28 specifically, but still useable with smaller movements and milder post-processing. If you do extreme things the microlenses can show up as "microlens ripple", and you can get "tiling", Capture One LCC algorithm corrects it well but not 100% perfect if you go extreme, so issues related to tiling and ripple appear on the forums now and then. If you have a "typical" shooting style and post-processing style you will probable never see any issues.

The best if you do extreme movements and/or use Schneider Digitar symmetrical wides are still the microlens free chips, and the highest end you can get there is the recently discontinued Hassy 50MP backs, CFV-50, H4D-50, H5D-50. When I upgraded from Aptus 75 I was looking into going to the Dalsa chip, but as I like the performance my Digitar lenses and did not want to absorb the lens upgrade cost, I went for a H4D-50 instead (for a smashing price), with external battery and all. Very happy with that.

If you aim for a higher end system with Rodenstock Digaron-W lenses the Credo 60 will be excellent though. Be prepared that you may get a strong desire for the Rodenstock Digaron-W 32mm...

 

[dougpeterson]

Much has been written about the 60mp dalsa sensor and 28XL and 35XL lenses. I suggest you do your own testing. In my testing and experience the Credo 60 gracefully handles the 35XL in all areas of the image circle which are sharp. This combo will produce color cast which cannot be fully corrected, and rippling which is not 100.0% corrected at the very edge of the image circle, but this area of the image circle is very soft/schmeered. The falloff in sharpness on the 35mm (or "36mm" as Alpa badges it) is a big reason why many users have switched to Rodenstock 40HR lenses. Despite having a smaller stated image circle, this lens is actually sharper over a larger range than the 35XL.

The reason you are hearing the Credo is excellent for tech cameras is because it is:
- internal battery (included, additional only $70 for branded, $30-40 off brand)
- retina resolution LCD for making determinations of focus/composition/content without a computer
- USB allowing connectivity to ultra portables such as the Microsoft Surface or MacBook Air.
- tap-to-100% to check focus on any area of the image immediately
- generous RAM to allow you to *instantly* change between different images (after they've been cached) to compare focus in an A:B manner
- works natively with Capture One (also with LR, ACR, IRD etc) which has a very advanced LCC routine (robust against under exposure, handles rippling, handles large amounts of fall off, and can correct dust)
- Capture One also has built in raw-level lens corrections for the distortion of the 40HR and several other Rodenstock lenses (more to come in the future)
- very reliable operation with copal shutters, and a great connector to the flash sync which is not likely to fall out accidentally
- counter which appears on screen during long exposures which is a handy replacement for pulling out your iphone timer or using "one mississippi... two mississippi..."

In my (highly biased and self-serving, but backed by lots of testing and users) opinion the very best all-around back for a tech camera right now is a 60mp Team Phase One back (Credo 60, IQ160, or IQ260 depending on the budget of the user). Some specific users might be better off with an 80mp or 50mp CMOS sensor depending on their lens and movement needs and their priorities of ease-of-use and resolution.

Again, don't take anyone's word for any of this. I'm biased as a dealer, and everyone is biased to their own priorities and experience. Go forth and test. Fortunately in this realm of pricing it's easy to arrange to do so!

==
Other tech camera resources:
A lens+back compatibility overview can be found here.
A chart of lens image circles can be found here.
A few hundred raw images that we (DT) have shot over the years in various tests over the years is available to our clients if you live in the US. If you live abroad I suggest contacting your local dealer to arrange relevant testing or receive already completed tests depending on what they have in their raw catalog.

 

[jlm]

doug:
could you point out the differences between a Credo and a Phase?

 

[dougpeterson]

doug:
could you point out the differences between a Credo and a Phase?

Gladly.

The IQ, IQ2, and Credo are all Team Phase One backs. The IQ and IQ2 carry Phase One branding while the Credo carries Leaf branding.

- Price: Generally the Credo is a bit less. This can vary based on promos and refurb vs. new.
- Warranty: IQ2 backs come with a 5 year warranty which includes a loaner during any repairs. IQ1 and Credo generally come with a 1 year warranty.
- Hard Buttons: IQ/IQ2 have hard buttons in addition to the touch interface. This is helpful while wearing gloves, and for navigating images without blocking the view of the screen. Also helpful when using back from an angle (i.e. if mounted high on a tripod or backed into a wall)
- Focus Mask: IQ/IQ2 have a tool called Focus Mask. It's very powerful if you know what to expect and how to use it. It will NOT show you (definitively) what is in focus or not, but it does show you what area of a similar subject area is most in focus, and can be used to very precisely compare the focus of two otherwise-similar images (e.g. before/after a change to tilt). Credo does not have this tool.
- Auto Perspective / Auto Horizon correction: All three backs have a 2-axis level in the user interface. The IQ/IQ2 embeds the value from this level in the metadata so that Capture One can automatically correct rotation or keystoning for one image or a batch of images.
- Wireless: the IQ2 includes wireless review/editing/control. The IQ1 and Credo do not.
- Color profiles: Capture One has color profiles for the Credo that are more in line with historical Leaf backs; the IQ/IQ2 have color profiles more in line with historical Phase One backs.

There are a few other minor differences like power button design, lock latch design (depending on date of manufacture) etc. But the above ones are the bigger differences.

 

[Paul2660]

To me the latch between the IQ1, and IQ2 is more than minor.

IQ1 you can use the latch with one hand, three steps, move the slider from the lock position, push the button and mount the back, move the slider back to the lock position.

IQ2, requires two hands, one to keep the slider pushed forwards, while you push the button. In the IQ2 the slider is spring loaded and will not stay in the unlock position without pressure being applied.

Overall the IQ2 has the better design as it's possible to move the IQ1 slider inadvertently forwards, and then if pressure is applied to the back release button the back will come off.

There also seems to be some confusion on if all IQ 1 & 2 have the style of the IQ2 now. I believe that the IQ1, 160, 150 and 180 all still have the older style of slider, i.e. non spring loaded. The IQ150 does for sure.

Also, since the IQ2 has wifi, there is a large plastic plate on top of the back, to allow the signal to get out. This IMO compromises the overall weather proofness of the IQ2, as I don't believe this is sealed all that well. For sure the top of the back is not as well protected as an IQ1 which has a solid casing on top.

Phase may have improved the seals on the plastic top I have no idea. I do know that my IQ260 did have a condensation problem where the inside of the LCD would fog. This was fixed when I had my top plate replaced. However I still put some electrical top over my top plate seams when I am working in possible rainy conditions.

You can expect about 8mm of shift from the SK35 before the issues that Doug mentioned become non correctable in post. This is with the CF on the lens. You can expect 15mm of full shift from the 40mm Rodenstock which has no CF. Possibly more tiling issues from the 35SK also.

Paul

 

[Lobalobo]

Thanks to all for responding. Although I'm a hobbyist, not a pro, and shoot 4x5 film, for reasons I can't explain I'm extraordinarily interested in this technology. (Perhaps I believe deep down that my wife will be happier with my buying mid-life crisis digital back than sports car as the former is unlikely to kill me.) That said, I hope no one took more time than he would have if it were known I'm not currently in the market. (And as I say, you never know.)

The attention to higher ISO is interesting and concerning if it's uniform across all new backs. With film, I use movements but not large ones and so it seems that if I do take the MF back plunge, I could use a newer micro-lens back with Rodenstock retro focus lenses (and the purchase would truly reach sports-car price territory). Still, avoiding micro lenses, if possible, would make movements that much easier, at a cost of lower ISO as I understand it. And as I learned in an earlier thread (from Doug), the flatter look some see in the CMOS backs (including, to my eyes, in Doug's Morgan Library test) is perhaps the product of a CFA tuned for higher ISO (not any inherent limitation in CMOS sensors).

So that's two impediments to the use of medium format backs on a technical cameras--micro lenses for high IS0 and weaker CFA for high IS0. Fine for some, who want the high ISO, but for others the trade-off is not a good one. Shouldn't there be some variety in the newer backs? Perhaps the market is so small that there isn't room for a single MF Back designed specifically for technical cameras used at low, base ISO. Too bad, though, if that's the case. Then again, what do I know. Currently just kibitzing ("chatting," of a sort, for those not Jewish, or from New York).

 

[torger]

I think the market is large enough to make a specific tech cam back if they would like, but the problem is instead on the sensor side. The Sony CMOS would have been great on tech cams if it just had light shielding between pixels (missing light shields is with the latest sensor designs a much larger problem than microlens artifacts), but tech cam get ~0 attention in the sensor design step.

With CMOS it seems like the traditional MFD companies Phase and Hassy got even less possibility to affect the sensor design. Sony wants to sell as many sensors as possible to as many manufacturers as possible and seems to have succeeded well. Clearly they did not take the tech cam segment into consideration, which I think is a bit worrying concerning the future, because CMOS will be taking over in the next years I'm sure of it. The advantages are just too large to stop it, and CCD is dead it just doesn't know it yet

If we're lucky BSI technology is coming to large sensors soon and then we'll probably get a tech cam friendly sensor "for free". (BSI is when the photo diodes are placed close to the surface rather than deep down in a well like on current sensors, and that increases sensitivity which everybody wants)

 

[Lobalobo]

So from what Torger says, the hope is for CCD to live long enough to see BSI. Interesting.

 

[Paul2660]

So from what Torger says, the hope is for CCD to live long enough to see BSI. Interesting.

Bigger issues is the basic design limitation of CCD, namely LiveView. It's been pretty much shown that CCD can work with LiveView albeit with severe limitations. These limitations make it just not very practical to use outdoors at least in my experience. One test with a CMOS back and it's Liveview will put a nail in that thought process.

The actual color loss on the 50MP Sony sensor due to Crosstalk IMO is minimal up to about 12mm of shift. I was very surprised to see this in testing I did. The amount of color/sat loss before the LCC is quite a bit, but C1 did an AMAZING job of getting it back within reason. In fact with the testing I did with the 40mm Rodie, C1 actually corrected the shifts on the 50MP back better than it does on my 260. And I did test this on a pure blue sky with a 28mm, 40mm and 60mm. The 50mp was easier to clean up on the shifts.

The loss of actual image due to the crop was extreme, and effected me a lot more than I thought it would. What I thought would just be a 3 or 4 backwards set of steps, was more like 12 to 14. In many cases I just could not frame the shot. The LCC on a shift is basically pure red or close to it on shifts of 10mm or more. You can also see this in the raw when viewed on camera LCD or tethered laptop. However when you apply the corrected LCC, the transition is really impressive, so again KUDOS to Phase One on this.

If and when a full frame CMOS back comes from Phase, I have concerns for I feel if they make it a great pixel pitch than the current 60MP backs, then tech camera use will not work, at least with current lenses from Rodenstock and Schenider. I am not going to move and lose my current glass investment. Just won't do that. I would rather move to a 50MP Sony 35mm when it comes and use the Aptus or Universalis.

It's also unclear when the next CMOS comes, will it be a Sony or ?. Sony has a proven track record with amazing DR with their latest Exmour chips so it will be interesting to see what the future brings.

Paul

 

[Lobalobo]

The actual color loss on the 50MP Sony sensor due to Crosstalk IMO is minimal up to about 12mm of shift. I was very surprised to see this in testing I did. The amount of color/sat loss before the LCC is quite a bit, but C1 did an AMAZING job of getting it back within reason. In fact with the testing I did with the 40mm Rodie, C1 actually corrected the shifts on the 50MP back better than it does on my 260. And I did test this on a pure blue sky with a 28mm, 40mm and 60mm. The 50mp was easier to clean up on the shifts.

If and when a full frame CMOS back comes from Phase, I have concerns for I feel if they make it a great pixel pitch than the current 60MP backs, then tech camera use will not work, at least with current lenses from Rodenstock and Schenider.

Paul

Thanks, Paul, for your response. I've looked at online and greatly admire your work. Based on what you say, if I understand correctly, you were able to shift a 28mm lens (presumably Rodenstock retrofocus) on the Sony chip and get good results. That's, roughly, what, 22mm field of view (in 35mm equivalents)? That's not to bad. Shifting aside, in your view does the CMOS chip (presumably in the IQ250 or Credo 50) provide the same color differentiation as the IQ260? (Some have said the CMOS CFA is noticeably weak to accomplish high ISO, but I'm not sure all agree.) Also your concern over full-frame CMOS is the same one I had explained to me at a camera tech show I visited, though I suppose lenses could be adjusted (made more retro) for those who are willing to pay.

Anyway, your view of the Sony chip is encouraging to me, because the Hasselblad CFV 50c is only $15,000, which is not far our of reach of an amateur such as myself, with not too much money but more money than sense (or skill). Something to think about, though I guess the Hasselblad wouldn't have the Capture 1 correction available and for a tech camera would still require the expensive Rodenstock lenses for tilt or shift at wide angle. In any case, thanks again.

 

[Paul2660]

The Hasselblad back tempted me also, but there will never be C1 support (I feel) for the Hasselblad and I am pretty much locked to C1. Plus I like my current dealer support structure and for now I am going to wait for the next back and see if it gets closer to full frame.

As for CMOS and CCD and look, I am one of the folks that just can't see much difference, possibly a bit more clarity in the CCD images but with Topaz Clarity I can get them very close.

I was able to get 10mm of shift on the 28mm with the IQ150. And 10mm is a real push due to the fact that the 70mm IC of the 28mm starts to show a lighter band vignette, before you hit the hard vignette of the internal IC indicator. Only the 70mm IC lenses seem to do this, but it's a real show stopper on a blue sky, but won't be as harmful on a non solid landscape subject matter.

Overall the best wide lens IMO for the 50MP back is the 32mm Rodenstock as it's going to give a lot more shift due to the 90mm IC. That lens is just a bit out of reach for me currently.

I used mainly the 40mm Rodie on my tests and was able to easily get to 15mm/18mm of shift on the 50mm back. What you start to see much past 15mm of shift is just too much damage from crosstalk. This shows up as pure red in the image and the LCC just can't pull that back. For a B&W subject it would be no problem as the details are still there, just very little recoverable color.

The 40mm Rodie's sweet spot was between 12 and 15mm of shift on the 50MP chip, as any past that and the loss in color was too much to pull back.

BTW you can also see this on the A7r, mounted to a Aptus or Arca DSLR2/Universalis. Take the A7r to 18mm and the far edge is pure red and very hard to recover in post.

Paul

 

[Lobalobo]

Thanks, Paul. In your most recent post you mention an IQ150 in your earlier post you mention the Sony chip; so was "150" a typo and did you mean "IQ250"? Thanks again.

 

[Paul2660]

Thanks, Paul. In your most recent post you mention an IQ150 in your earlier post you mention the Sony chip; so was "150" a typo and did you mean "IQ250"? Thanks again.

Hi, actually all three Credo 50, IQ150 and IQ250 share the same Sony chip that the Hasselblad 50c and 645z use.

Paul

 

[Lobalobo]

Thanks, Paul. Got confused by the "1" in "150" back assuming it was an older back.