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DT's IQ4 Tech Camera Test Teaser

dougpeterson

Workshop Member
Re: DT's IQ4 Tech Camera Test Teaser (full article now available)

To my eye, it's better than my clients ever have seen.

So, we are living in the Hell under the Sky.:facesmack:
The skies have favored us. As requested here is a [43XL (no center filter) with 10mm rise and NO color cast correction, only light falloff correction] shot of a clear-blue sky all the way to the edge:

4862.jpg

By way of comparison here is the same shot with an IQ3 100mp Trichromatic. No color cast correction, only light falloff correction.

0152.jpg
 

med

Active member
Re: DT's IQ4 Tech Camera Test Teaser (full article now available)

The skies have favored us. As requested here is a [43XL (no center filter) with 10mm rise and NO color cast correction....
Wow, that’s quite incredible. Thanks for testing and sharing Doug!
 

Pemihan

Well-known member
We haven’t this lens either. Aren’t you in Arizona? How close to Phoenix? We will be there next week. Let me know if you want to meet up to test it.
No, I'm in Denmark, but will be back in Arizona late March / early April. I could bring my 35XL or maybe I can get a chance to test it here.
 

dchew

Well-known member
Peter,
Doug and I are attempting to meet up over Thanksgiving here in Ohio. We will put my 35xl to the test with and without the CF.

Dave
 

jng

Well-known member
Careful, Dave. What you think is a slippery slope is actually a cliff!:bugeyes:

John

Peter,
Doug and I are attempting to meet up over Thanksgiving here in Ohio. We will put my 35xl to the test with and without the CF.

Dave
 

Aviv1887

Member
Hi Doug, do you dare to say that the sensor vignetting is less pronounced that the IQ3100? Resulting in less correction to do for the LCC, less saturation loss and bigger movements possible again?
 

dougpeterson

Workshop Member
Hi Doug, do you dare to say that the sensor vignetting is less pronounced that the IQ3100? Resulting in less correction to do for the LCC, less saturation loss and bigger movements possible again?
Yes, I say that now without hesitation.

The only caveat I’ll note is that the lens sharpness itself is still a factor in calculating range of movement. The Schneider digitar lenses in particular are not critically sharp to the edge of the stated image circle; Schneider was always “generous” with the image circle they ascribed their digitar lenses. This is less important when the corners of the frame are clear blue sky or featureless ceiling. And, notably, Rodenstock HR lenses are sharp to the edge of their states image circle (in some cases they are sharp for several mm beyond their stated circle).

But yes, regarding sensor fall off and color cast the IQ4 is a *huge* improvement on every tech camera lens I’ve tested.

Then you have improved live view, live focus mask, faster interface, better screen sharpness, hugely improved dark frame workflow, faster ES, dual storage, wireless tethering, option to power from a usb-c power brick (eg when shooting star trails) and like a half dozen other things I’m probably forgetting. All of these will be welcome usability improvements for some tech camera users.

The frame averaging feature (currently in “LAB” aka beta) also is very promising for static subject matter for a tripod, though we have not been able to test this ourselves so I’ll remain slightly skeptical until I’ve been able to play with it in the real world. But the potential is pretty huge.

As a general rule I try not to be so gushing when describing a product we sell as it can come off a bit fake (I try very hard to give objective, truthful, evidence-based advice, but I'm well aware that my job biases me). But in this case I just can’t help it - after the testing we have done I can say without reservation that the IQ4 150mp is the largest jump in Tech Cam usability and pleasurability-to-use since the first portable digital backs in the early 2000s (prior to which you had to tether). I’ve been a tech cam nerd/fan since the first time I used one and I’ve never looked forward to a new product more.

And that’s putting aside the promise of the Infinity Platform: Phase One have more tricks up their sleeve that will make the back even better over time (via free firmware updates).

Of course, it’s got some more pixels too. :)
 
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f8orbust

Active member
The only caveat I’ll note is that the lens sharpness itself is still a factor in calculating range of movement. The Schneider digitar lenses in particular are not critically sharp to the edge of the stated image circle; Schneider was always “generous” with the image circle they ascribed their digitar lenses. This is less important when the corners of the frame are clear blue sky or featureless ceiling. And, notably, Rodenstock HR lenses are sharp to the edge of their states image circle (in some cases they are sharp for several mm beyond their stated circle).
You've always got to bear in mind that there are very few tech cameras that can actually reach the edge of the full image circle of a lens like the 90mm HR SW (you'd need to shift ~30mm) or the SK 120mm ASPH (~45mm), so whether or not edge resolution is an issue will depend on what lens/camera is being used.

Also, before everyone rushes to sell their kids on eBay in order to buy a new set of R/Ss, remember there is soooo much more to a lens than simply out-and-out resolution (rendering, color, distortion, bokeh, flare, contrast etc.).
 

Uaiomex

Member
These tests alone (tho I can't afford it) makes me lust even more for the IQ4 and have even more respect for the Sony sensor division.
I was under the impression that BSI was mainly good for the very small formats. But this is huge!


Careful, Dave. What you think is a slippery slope is actually a cliff!:bugeyes:

John
 

Bill Caulfeild-Browne

Well-known member
I attended an unveiling of the IQ4-150 in Toronto on Thursday and got to play with it (with others) for a couple of hours. Blew me away. Although I'm not a tech cam user (XF works for me!), everything Doug says above is 100% true. Now we're both gushing!
 

Phase V

Member
Is it possible with the IQ4 and a normal tech-cam setup (Rodenstock HR lens, copal
shutter, wake up cable, cable release) to have the live view on something like a atomos ninja?
 

dougpeterson

Workshop Member
Is it possible with the IQ4 and a normal tech-cam setup (Rodenstock HR lens, copal
shutter, wake up cable, cable release) to have the live view on something like a atomos ninja?
Yes. Regardless of whether you use the copal or sensor-based shutter you can use the recessed HDMI-Mini out port to connect to any HDMI monitor (e.g. 100" TV, 4" portable monitor, or even a projector). In HDMI out you can display:
- live view zoom-to-fit
- live view at 100% anywhere in image
- live histogram, live raw histogram, live clipping warning lights
- focus mask (in either zoom-to-fit or at 100%) with customizable threshold
- the User Interface (e.g. if you're teaching a class on the IQ you can use HDMI to show whats on the screen).

Note:
- If you are using ES then you can capture while HDMI live view is running. It will pause for around a second (plus the length of the exposure) before resuming automatically. Since you no longer need to capture a dark frame this means a tech camera with HDMI can capture without touching the camera.
- HDMI out does not preclude or negate tethering. You can still be tethered via ethernet, usb-c, or wireless. This is great for working with non-digital-tech assistants, art directors, or stylists since they can see a live feed of the image without touching/using/disrupting your tethered station or camera.
- If HDMI out is active then Live View cannot be used on any other device (the back, the computer, your phone etc). Live View can only be displayed in one place at a time.
 

dchew

Well-known member
Well, Doug continues to "tease."

I met him and his lovely wife in Northern Ohio. Tested the 35xl with and without a center filter. Doug can show you all the images if he wants (he takes better notes than I do anyway). It was a crappy day so we tested inside. The focus point was about 15 ft. Not infinity, which would be worst case, but close enough on this lens. After I got home, I repeated the LCC's at about the same focus distance with my IQ3100. All images at f/11.

My opinion: With the IQ4150, the limit to this lens is the lens itself. Those of you who have it know when you get out to 15-20mm it gets pretty soft anyway, so shifting out that far is not all that useful. Probably cannot get away without using the CF and not taking an LCC. But if you don't need too much rise/fall/shift, you certainly wouldn't need the CF. It is pretty clear to me that the LCC will clean up images with no issues or desaturation. This back has what I would call significant benefits to tech camera users:
  • Color cast barely exists on many lenses, and is easily dealt with on the tougher lenses like this one.
  • Focus peaking is useful and very well implemented.
  • I see little, if any, reason to take black reference frames. No more forgetting to re-open the shutter!! Not that I ever did that...
  • The electronic shutter is faster, but to be honest I've never had an issue on the 3100; I use it constantly.
Note the order between the two backs is not the same, so pay attention to the labels. Pretty obvious which image is which anyway.

Dave

IQ3100:



IQ4150:
 
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