The GetDPI Photography Forum

Great to see you here. Join our insightful photographic forum today and start tapping into a huge wealth of photographic knowledge. Completing our simple registration process will allow you to gain access to exclusive content, add your own topics and posts, share your work and connect with other members through your own private inbox! And don’t forget to say hi!

Phase One IQ1 80 vs. IQ3 80 Live View

pks

New member
Hi!

I've been using my IQ1 80 for a while exclusively for landscape photography. While I'm really happy with the files I get out of it, the image taking process could be more enjoyable: Focusing is and has been always a pain on my ALPA 12 TC, especially in lower light conditions. Thus I wondered if the IQ3 80 would have an advantage over the older back. I know that it has a newer Sensor and supports WiFi (the most notable features to me), but I cannot find info whether live view has been improved.

Does anyone have experience with both backs on a technical camera?

Thanks a lot!
 

drevil

Well-known member
Staff member
Hey pks, its the same ccd sensor from dalsa and i doubt that there were any improvements with the live view.

maybe dynamic range has improved a bit via tweaking the software but its the same sensor technology
 

Steve Hendrix

Well-known member
Hey pks, its the same ccd sensor from dalsa and i doubt that there were any improvements with the live view.

maybe dynamic range has improved a bit via tweaking the software but its the same sensor technology

The live view performance is the same for any Phase One IQ 40mp/60mp/80mp digital back, regardless of generation (1/2/3). This is due to the CCD-based technology.

Phase One IQ 50mp/100mp/150mp models are a different story, as these are cmos-based technology.

FWIW - below is a very recent refresh on IQ 60mp/80 long exposures, but it also touches on some of the differences between IQ1/2/3.

https://www.captureintegration.com/...e-one-iq360-vs-phase-one-iq380-long-exposure/


Steve Hendrix/CI
 

JeffK

Well-known member
I'm in a similar boat. I've got an IQ260Achromatic. No live view at all. It's essentially an IQ160 but has wifi and USB3. Long exposure is limited to 2 min, but most of my LE shots are around a minute anyways.

My solution to lack of live view was to buy an inexpensive laser measure device. For anything less than infinity focus it's very helpful. it's not live view, but it was $30 at the time and was less than the extra $13k it was going to cost to get the IQ3100A instead.
 

dchew

Well-known member
I used to say something crazy and controversial after I upgraded from the IQ180 to the 3100: I felt focusing using the Alpa HPF rings and a Leica Disto was more accurate than what you could see in live view.
I’m not saying I would give up live view. But if you are not using tilt, I still think the HPF rings can be remarkably accurate.
Dave
 

Ben730

Member
I can confirm: Alpa HPF rings with a Leica Disto are very accurate. I recommend the Disto to measure in sunlight.
Regards,
Ben
 

doccdiamond

Member
Fully agree - Alpa HPF and Leica Disco (or something similar) are pretty precise! Live View of the great CCD sensor is basically suitable for framing...

Best

Peter
 

drevil

Well-known member
Staff member
I am surprised by the info from steve, i didnt know at all that phase managed to bring long exposure back to the ccd backs, results looking really good.
its really a BIG shame that phase stopped to make backs for other cameras than their own. would have loved to use a iq380 on my contax.
 

Ray Harrison

Well-known member
I think the 380 had both H and V mounts available to it in addition to XF. I agree that it would have been lovely if it had the Contax mount as well.
 

drevil

Well-known member
Staff member
I think the 380 had both H and V mounts available to it in addition to XF. I agree that it would have been lovely if it had the Contax mount as well.
i actually had the idea, maybe its possible to 3d print a contax mount frame and replace it on an iq3100 or iq4150. those have ES, so no biggy.

now i realized some guys in china offering this modification, dont know the price though
 

FloatingLens

Well-known member
Wow, and shoot through B mode on the Contax then? The camera body is complaining in B mode if a P-back is attached, so that would solve that, too. 😎

Is the total flange distance of the XF shorter than C645?
 

buildbot

Active member
Wow, and shoot through B mode on the Contax then? The camera body is complaining in B mode if a P-back is attached, so that would solve that, too. 😎

Is the total flange distance of the XF shorter than C645?
It might be, but the problem is that you’d have to deal with the C645 mount prongs not matching the M645 ones, as they are both mounted on the body and not the back. I think what @FloatingLens is referring to is a permanent modification of the back by replacing the frame that the sensor is mounted to with one made for the C645. I haven’t seen this, but I did see someone who did such a swap to a Rollei HY6 Mount.

The Hy6 is actually much easier to design for, the mounting prongs are on the back side so you can design and adapter with minimal thickness and the matching mounts on both sides, like so:

B5FE553C-B226-47C2-ABBC-A9E8BB74DC1E.jpeg
 

drevil

Well-known member
Staff member
thats pretty much what i meant, replace the mount frame for one that fits the contax.
shoot the contax in B mode
 

shanhw1978

New member
It might be, but the problem is that you’d have to deal with the C645 mount prongs not matching the M645 ones, as they are both mounted on the body and not the back. I think what @FloatingLens is referring to is a permanent modification of the back by replacing the frame that the sensor is mounted to with one made for the C645. I haven’t seen this, but I did see someone who did such a swap to a Rollei HY6 Mount.

The Hy6 is actually much easier to design for, the mounting prongs are on the back side so you can design and adapter with minimal thickness and the matching mounts on both sides, like so:

View attachment 191904
Hi buildbot
Where did you find the adapter for Hy6 mount from M645?
Thanks.
 

ErikKaffehr

Well-known member
I used to say something crazy and controversial after I upgraded from the IQ180 to the 3100: I felt focusing using the Alpa HPF rings and a Leica Disto was more accurate than what you could see in live view.
I’m not saying I would give up live view. But if you are not using tilt, I still think the HPF rings can be remarkably accurate.
Dave
Very interesting view point.

It is totally feasible. But I also have some doubts...

In principle, the approach with a laser distance meter and high precision focusing ring should be very accurate, but there may be some variables like focus shift and thermal expansion that may be problematic to handle.

I learned a lot from Jim Kasson:
  • Focus at optimal magnification
  • Use peaking with magnification
  • Focus at intended shooting aperture
These things sort of go hand in hand. Stopping down reduces some remaining aberrations, so the image snaps more clearly in and out of focus. It is also easier to get peaking when shooting stopped down.

But, once we get to say f/11, diffraction comes into play and most of the focus shift is probably gone. So, it may make sense to focus at f/8 when shooting at smaller apertures.

Much interested in your thoughts.

Best regards
Erik
 

dchew

Well-known member
Very interesting view point.

It is totally feasible. But I also have some doubts...

In principle, the approach with a laser distance meter and high precision focusing ring should be very accurate, but there may be some variables like focus shift and thermal expansion that may be problematic to handle.

I learned a lot from Jim Kasson:
  • Focus at optimal magnification
  • Use peaking with magnification
  • Focus at intended shooting aperture
These things sort of go hand in hand. Stopping down reduces some remaining aberrations, so the image snaps more clearly in and out of focus. It is also easier to get peaking when shooting stopped down.

But, once we get to say f/11, diffraction comes into play and most of the focus shift is probably gone. So, it may make sense to focus at f/8 when shooting at smaller apertures.

Much interested in your thoughts.

Best regards
Erik
Hi Erik,
I've never been able to detect focus shift on lenses slower than f/4. I'm sure it occurs and perhaps Jim could measure it. I just can't see it within the increased DoF. I think the thermal expansion impact is similar. If I was shooting at f/2.8 or f/4 maybe it would be a problem. But at f/8-f/16 I suspect that would require quite the temperature change on a relatively complicated assembly like a lens (I don't think a solid rod would be a good model). Not to mention the effects of diffraction messing up the works.

My "accurate focus" is within the context of shooting with technical cameras at the accuracy required for ~f/11. For example, I don't focus at the intended shooting aperture. I find it is easier and faster (for me) to focus wide open then stop down, at least with the marginal screens supplied on Phase One's backs. When zoomed in, I think the image snaps more clearly in and out of focus when the lens is wide open, not stopped down. I do use the other two techniques listed in your bullet points.

Dave
 
Top