Hi Manni,Mind sharing your tips to get i1pro2 to read gamma at low IRE levels?I keep getting a reading of zero on the first gamma step of Red. (iris is already set to max)
Yes you do need a different LUT for SDR BT709 and SDR BT2020 (it's not advised to use a static HDR 3D LUT because that means you can't use automatic tonemapping, whether static in the JVC/player or dynamic in madVR/Radiance Pro).Unless you zoom the picture down to its minimal size (and even then, I'm not sure it will be accurate enough), you can't use the i1pro2 for a 3D LUT. It can't read the dimmest patches accurately, this will cause a lot of issues especially near black and with blue. You have to train the Spyder to the i1pro2 and use the profiled Spyder to generate the LUT in Calman. See a few posts above for tips to profile a meter to a spectro.A 3D LUT will NOT visibly improve things if you're already spot on after an Autocal. In fact, it can make the picture worse. So I would advise to only make a LUT if there are significant errors that the Autocal and manual fine-tuning can't resolve. If, after setting white to D65 using the i1pro2, you have gamma/gamut (including saturations) under 3dE accross the range, and a colorchecker SG with all points under 3-4, I would say don't bother with the 3D LUT. You're going to waste hours of good lamp time for little to no visible improvement, unless you can get significant improvements with a Lightning LUT (which works well after an Autocal). Remember, if you're picky, you have to redo the calibration every 200 hours or so, due to lamp drift.
I see how to profile the Spyder using the i1pro2,is the Spyder ok to use for this and would I then point the Spyder at the screen to do my reads?I played around more last night and the only thing that is baffling me is 2020, when I do a read of 709 (using the i1pro2) everything color wise looks pretty spot on but if I do the same read of 2020 (with the filter engaged on the JVC) lots of point (especially the top green) are WAY off so I am wondering if I am doing something wrong? I am using the 2020 default CMS and telling the Lumagen to output SDR2020 (verifying with JVC info). Anything else I need to do to get a proper 2020 read?
The spyder points the way it points when you profile it to the i1pro2. It should work fine pointing at the screen, as long as it doesn't read its own shadow or the i1pro2 shadow.You need to post screenshots, but there are two ways things could look like they are wrong in measurements when they are fine:1) You have not set the target in the calibration software you are measuring2) You don't realise that the projector will never reach bt2020, only P3. If you want to see a nicer looking graph, measure P3 within BT2020, not BT2020.With the filter, the PJ can reach 100% of DCI-P3, but that's only around 70% of P3, so if BT2020 looks undersaturated, that's what it is.If it looks oversaturated, that might be because you left the target on rec-709.But again, without screenshots of your measurements, it's impossible to tell.
I get it now, the RS 2000 cannot even do BT2020? Should we still be using SDR2020 though it just wont get the full benefit or should we be using 709 or something it can do? I will do some screens this weekend, greatly appreciate the help.
You can't really do a gamma autocal with an i1pro2, unless you zoom down the picture to the minimum size, and if that's not enough use a piece of white board that you bring closer to the lens (assuming you can't bring the PJ closer).Otherwise, even if the value is non-zero, it's probably garbage under 10% white anyway, and not far from garbage under 20% white. When you read gamma with an i1pro2, you can see that anything below 10-15% is complete garbage and should be ignored, so you definitely can't use it for calibration of low brightness levels, it's not designed for that. A spectro is best used to do high brightness color work, or to profile a faster/more accurate in low light tristim such as the Spyder.If you do manage to get good gamma autocal results with the i1pro2 without the zoom/cardboard tip suggested above (and even with that, I'm not 100% sure I'd trust the i1pro2), let us know!I haven't tried to do gamma with the i1pro2 because I use the Spyder 5 for gamma autocal. So my suggestion is to buy one and use it for gamma. A Spyder 5 Express (if you can still find one) isn't that expensive and it does the job well.
I foolishly sold my Spyder 5 after I bought the i1pro2 Anyway, reducing the screen size did the trick. Here's what I did: - zoom to minimum size- ipro2 is positioned 10cm away from screen- the shadow of the ipro2 sits below the screen and the ipro2 itself is angled upwards - ditched my usb extension cable and plug it directly to my laptop (not sure if this makes a difference)After doing all that, I was able to barely get the i1pro2 inside the rectangle in autocal. Previously it was sitting outside the rectangle just like what you have written in your guide.I haven't done a full check in HCFR, but near black readings don't have a red haze anymore.That's enough for me for now
Any rumors or news on support for the new i1Basic Pro 3 Plus?
1454 Replies
317011 Views